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[Question]
[
Suppose your alarm wakes you up one morning, but you hit snooze so you can sleep for 8 more minutes. When it rings again you grudgingly get up and take a shower, which you estimate takes 15 to 17 minutes. You then brush your teeth for exactly 2 minutes, and get dressed, which takes about 3 to 5 minutes. Finally, you eat a hurried breakfast in 6 to 8 minutes and run out the door.
We can denote this timing sequence as `8 15-17 2 3-5 6-8`.
*Given the uncertainty of your morning's routine, what is the probability you were doing each task at some particular number of minutes since you first woke up?*
Assuming every task takes a whole number of minutes, we can chart every possible combination of uncertain time spans (e.g. 3, 4, and 5 minutes for brushing teeth). This chart shows all 27 possibilities, with time increasing to the right, and each task of N minutes represented by (N - 1) dashes and one vertical bar, just to mark its ending. The minute boundaries occur *between* characters, so the space between the `8` and `9` column is `8 min 59 sec` turning into `9 min`.
```
1111111111222222222233333333334
1234567890123456789012345678901234567890 <-- Minute
-------|--------------|-|--|-----|
-------|--------------|-|--|------|
-------|--------------|-|--|-------|
-------|--------------|-|---|-----|
-------|--------------|-|---|------|
-------|--------------|-|---|-------|
-------|--------------|-|----|-----|
-------|--------------|-|----|------|
-------|--------------|-|----|-------|
-------|---------------|-|--|-----|
-------|---------------|-|--|------|
-------|---------------|-|--|-------|
-------|---------------|-|---|-----|
-------|---------------|-|---|------|
-------|---------------|-|---|-------|
-------|---------------|-|----|-----|
-------|---------------|-|----|------|
-------|---------------|-|----|-------|
-------|----------------|-|--|-----|
-------|----------------|-|--|------|
-------|----------------|-|--|-------|
-------|----------------|-|---|-----|
-------|----------------|-|---|------|
-------|----------------|-|---|-------|
-------|----------------|-|----|-----|
-------|----------------|-|----|------|
-------|----------------|-|----|-------|
1234567891111111111222222222233333333334 <-- Minute
0123456789012345678901234567890
```
It is clear that the routine could have taken 40 minutes at most and 34 minutes at least.
The question is, at a particular minute, say minute 29, what is the chance you were doing each of the 5 tasks? Assume each uncertain time frame is uniformly distributed over the exact whole minutes. So a 4-7 task has 25% chance of taking 4, 5, 6, or 7 minutes.
From the chart it can be seen that at minute 29 there was a...
```
0/27 chance you were snoozing (task 1)
0/27 chance you were showering (task 2)
0/27 chance you were brushing (task 3)
24/27 chance you were dressing (task 4)
3/27 chance you were eating (task 5)
```
Similarly at minute 1 there was a `27/27` chance you were snoozing with `0/27` everywhere else.
At minute 38 for example, 17 of the potential routines have already ended. So in 10 out of 10 cases you will be eating. This means the probabilities look like
```
0/10 task 1, 0/10 task 2, 0/10 task 3, 0/10 task 4, 10/10 task 5
```
# Challenge
Write a *function* that takes an integer for the minute value, and a string consisting of a sequence of single integers, or pairs of integers `a-b` with `b` > `a`, all separated by spaces (just like `8 15-17 2 3-5 6-8`). All the integers are positive. The input minute will be less than or equal to the maximum time possible (40 in example).
The function should return another string denoting the **unreduced** fractional chance of being in each task at the given minute.
# Examples
* `myfunc(29, "8 15-17 2 3-5 6-8")` returns the string `0/27 0/27 0/27 24/27 3/27`
* `myfunc(1, "8 15-17 2 3-5 6-8")` returns the string `27/27 0/27 0/27 0/27 0/27`
* `myfunc(38, "8 15-17 2 3-5 6-8")` returns the string `0/10 0/10 0/10 0/10 10/10`
* `myfunc(40, "8 15-17 2 3-5 6-8")` returns the string `0/1 0/1 0/1 0/1 1/1`
If your language does not have strings or functions you may use named variables, stdin/stdout, the command line, or whatever seems most appropriate.
# Scoring
This is code golf. The shortest solution [in bytes](https://mothereff.in/byte-counter) wins.
[Answer]
## CJam, ~~124 115 100 92~~ 89 bytes
This can be golfed a lot, but I have to sleep, so posting now itself :)
```
l~\:N;S/{'-/2*2<~i),\i>}%_{m*{(\+}%}*{[0\{1$+}*]}%:B;,,{0B{I>2<~N<!\N<*+}/}fI]_:+m*'/f*S*
```
[Try it online here](http://cjam.aditsu.net/)
Input is like:
```
29 "8 15-17 2 3-5 6-8"
```
Where first integer is the input minute and the second string is the time range sequence (as shown in examples in the question, just without the `,`)
Output for the above mentioned input:
```
0/27 0/27 0/27 24/27 3/27
```
[Answer]
## Mathematica, ~~237~~ 216 bytes
I'm sure I can shorten this a bit, but not now. At least I finally got to use the new associations from Mathematica 10! :)
```
f=(j=#;s=StringSplit;r=ToString;t=Lookup[Counts@Flatten[FirstPosition[#,n_/;n>=j]&/@Accumulate/@Tuples@i],#,0]&/@Range@Length[i=ToExpression[#~s~"-"&/@s@#2]/.{a_,b_}:>a~Range~b];Riffle[r@#<>"/"<>r@Tr@t&/@t," "]<>"")&
```
Ungolfed:
```
f = (
j = #;
s = StringSplit;
r = ToString;
t = Lookup[
Counts@Flatten[
FirstPosition[#, n_ /; n >= j] & /@
Accumulate /@ Tuples@i], #, 0] & /@
Range@Length[
i = ToExpression[#~s~"-" & /@ s@#2] /. {a_, b_} :> a~Range~b];
Riffle[r@# <> "/" <> r@Tr@t & /@ t, " "] <> "") &
```
Usage as specified in the challenge:
```
f[29, "8 15-17 2 3-5 6-8"]
```
It returns `0/1` for all elements if the first input is larger than the maximum time span.
[Answer]
# Haskell, 232
```
f=(\(a,b)->[a..fst$head$reads(tail$b++" ")++[(a,b)]]).head.reads
n%l=(tail>>=zipWith(-))(0:map(\i->drop i&l*e[x|x<-map sum$mapM f$take i$w l,x>=n])[1..e$w l])>>=(++'/':show(id&l)++" ").show
(&)i=product.map(e.f).i.w
w=words
e=length
```
run like this:
```
*Main> putStrLn $ 1 % "8 15-17 2 3-5 6-8"
27/27 0/27 0/27 0/27 0/27
```
[Answer]
## APL, [162](https://mothereff.in/byte-counter#%7B%7B%E2%8D%B5%2C%27%2F%27%2Cy%7D%C2%A8%E2%8C%8A%7C-2-%2F0%2C%28y%E2%86%90%2B%2F%2C%E2%8D%BA%E2%89%A4%E2%8A%83%E2%8C%BDx%29%C3%971%2C%E2%8D%A8%C2%AF1%E2%86%93%E2%8D%BA%7B%2B%2F%C3%B7%E2%88%98%E2%8D%B4%E2%8D%A8%E2%8D%BA%E2%89%A4%2C%E2%8D%B5%7D%C2%A8x%E2%86%90%E2%88%98.%2B%5C%7B%E2%8A%83%7B%E2%8D%BA%2C%E2%8D%BA%E2%86%93%E2%8D%B3%E2%8D%B5%7D%2F%E2%8D%8E%28%27-%27%E2%8E%95R%27%20%27%29%E2%8D%B5%7D%C2%A8%28%27%5CS%2B%27%E2%8E%95S%27%5C0%27%29%E2%8D%B5%7D)
```
{{⍵,'/',y}¨⌊|-2-/0,(y←+/,⍺≤⊃⌽x)×1,⍨¯1↓⍺{+/÷∘⍴⍨⍺≤,⍵}¨x←∘.+\{⊃{⍺,⍺↓⍳⍵}/⍎('-'⎕R' ')⍵}¨('\S+'⎕S'\0')⍵}
```
**Example runs**
```
f←{{⍵,'/',y}¨⌊|-2-/0,(y←+/,⍺≤⊃⌽x)×1,⍨¯1↓⍺{+/÷∘⍴⍨⍺≤,⍵}¨x←∘.+\{⊃{⍺,⍺↓⍳⍵}/⍎('-'⎕R' ')⍵}¨('\S+'⎕S'\0')⍵}
29 f '8 15-17 2 3-5 6-8'
0 / 27 0 / 27 0 / 27 24 / 27 3 / 27
1 f '8 15-17 2 3-5 6-8'
27 / 27 0 / 27 0 / 27 0 / 27 0 / 27
38 f '8 15-17 2 3-5 6-8'
0 / 10 0 / 10 0 / 10 0 / 10 10 / 10
40 f '8 15-17 2 3-5 6-8'
0 / 1 0 / 1 0 / 1 0 / 1 1 / 1
```
I hope you don't mind the weird spacing
] |
[Question]
[
This question is slightly harder than the ASCII art version. There is no art, and now you get to do some floating point arithmetic!
# The Challenge
The U.S.S. StackExchange was traveling through the gravity field of planet cg-00DLEF when an astronomical explosion occurred on board. As the head programming officer of the ship, it is your job to simulate the trajectory of your ship in order to predict whether you will be forced to crash land in cg-00DELF's solar system. During the explosion, your ship was heavily damaged. Due to the limited free DEEEPRAROM\* of the spaceship, you must write your program in as few characters as possible.
\*Dynamically Executable Electronically Erasable Programmable Random Access Read Only Memory
# The Simulation
Somewhat like the ASCII art version, there will be the idea of time-steps. In the other version, a time-step was a relatively large amount of time: the ship could travel way beyond the gravity of a planet in a single time-step. Here, the time-step is a much smaller unit of time due to the larger distances involved. One major difference, however, is the non-existence of cells. The spaceship's current location and velocity will be floating point numbers, along with the gravitational forces involved. Another change is the fact that planets now have a much larger size.
There will be up to three planets in the simulation. All three will have a specific location, radius, and gravity. The gravity for each planet is a vector that exerts a force directly towards the center of the planet. The formula to find the strength of this vector is `(Gravity)/(Distance**2)`, where the distance is the exact distance from the ship to the center of the planet. This means that there is no limit to where gravity can reach.
At any specific time, the spaceship has a velocity, which is the distance and angle that it traveled from last time-step to now. The ship also has momentum. The distance that it will travel between the current time-step and the next is the sum of its current velocity added to all of the gravity vectors at its location. This becomes the spaceship's new velocity.
Each simulation has a time limit of 10000 time steps. If the spaceship travels inside of a planet (it is closer to the center of the planet than the planet's radius), then it crashes into that planet. If the spaceship does not crash into any planet by the end of the simulation, then it is presumed to have escaped from gravity. It is unlikely that the ship could be aligned so perfectly that it manages to stay in orbit for 10000 time-steps while crashing on the 10001st time-step.
# Input
Input will be four lines to STDIN. Each line consists of four comma-delimited numbers. Here is the format of the numbers:
```
ShipLocX,ShipLocY,ShipVelX,ShipVelY
Planet1LocX,Planet1LocY,Planet1Gravity,Planet1Radius
Planet2LocX,Planet2LocY,Planet2Gravity,Planet2Radius
Planet3LocX,Planet3LocY,Planet3Gravity,Planet3Radius
```
If there are fewer than three planets, then the leftover lines will be filled with zeros for all values. Here is an example input:
```
60,0,0,10
0,0,4000,50
100,100,4000,50
0,0,0,0
```
This means that the spaceship is located at (60,0) and is traveling straight "up/north" at a rate of 10 units/time-step. There are two planets, one located at (0,0) and one at (100,100). Both have a gravity of 4000 and a radius of 50. Even though all of these are integers, they will not always be integers.
# Output
Output will be a single word to STDOUT to tell whether the spaceship has crash landed or not. If the ship crash lands, print `crash`. Otherwise, print `escape`. Here is the expected output for the above input:
```
crash
```
You may be wondering what happened. [Here](http://pastebin.com/LgLTabpj) is a Pastebin post that has a detailed flight log for the spaceship. Numbers aren't very good at helping people visualize the event so here is what happened: The spaceship manages to escape the gravity of the first planet (to its west) with the help of the gravity of the second planet (to its northeast). It moves north and then passes slightly to the west of the second planet, barely missing it. It then curves around the northern side of the planet and crashes into the eastern side of the second planet.
# Some more cases for examination
```
60,0,10,-10
0,0,2000,50
100,100,1357.9,47.5
0,0,0,0
```
escape (due to the inverse square law, 2000 isn't much gravity if you are 60 units away)
```
0,0,0,0
100,100,20000,140
-50,-50,50,50
-100,-100,50,50
```
crash (the first planet is extremely massive and extremely close)
```
0,0,0,0
0,0,0,0
0,0,0,0
0,0,0,0
```
escape (this is an edge case: there are no planets and a straightforward interpretation would suggest that the spaceship is directly on top of the planets)
# Rules, Restrictions, and Notes
This is code golf. Standard code golf rules apply. Your program should be written in printable ASCII characters only. You cannot access any sort of external database. You may write entries in any language (other than one that is specialized towards solving this challenge).
End Transmission
[Answer]
## Python, 178 170 chars
```
p=input
a,b,c,d=p()
x=a+b*1j
v=c+d*1j
P=(p(),p(),p())
R='escape'
for i in' '*10000:
for a,b,g,r in P:
d=a+b*1j-x;v+=g*d/abs(d)**3
if abs(d)<r:R='crash'
x+=v
print R
```
[Answer]
## Golfrun/GolfScript?, ~~243~~ 232 chars
```
10000:M;n%(','%2/{{~}%}/{{M*}%}:_~:v;_:x;'escape':R;{[','%2/{{~M*}%}/]}%:P;
M,{;P{~\x{0\-}%{+~@+@@+[\]}:|~:d.[~0\-]{[+.2%~*\.-2%~*@\-\.3%~*\(;);~*+]}:&~);~sqrt:z
..**\~d@[`~0]\&@M.*/\{1$/}%v|:v;;z\<{'crash':R;}{}if}/x v|:x;}/R puts
```
Golfrun is a language I'm working on, born as GolfScript C interpreter, but soon drifted away someway; though I've written this code without using knowingly specific Golfrun features (except for `sqrt`), the test with the original GolfScript failed (I had to add the sqrt feature to the original code, I am not a Ruby guru but I believe the problem is not my tweaking).
The first problem with this solution is that Golfrun, as GolfScript, has no floating point math. It is "simulated" magnifying the numbers, hopefully in the correct way (but I am not 100% confident I've done it coherently).
Even so, the solution does not handle floating point numbers as input, so I had to magnify them by hand to have only integer numbers.
Trying to implement the algorithm in the Python code, I have also implemented bits of complex math in a rather "general" way. Manipulating the algorithm in order to avoid this, and/or inlining whenever possible, delaying the definitions, could save other chars...
How do I know this code works? Indeed, I am not sure it does! But giving the examples as input (after "removing" points where they appear), it wrote the expected results, except for the "corner case" (which raises an exception in Python too)...
] |
[Question]
[
This question is an extension of [Who's that Polygon?](https://codegolf.stackexchange.com/q/121815/110698) to arbitrary numbers of sides.
A [fundamental polygon](https://en.wikipedia.org/wiki/Fundamental_polygon) for a surface is an polygon with a prescribed pairing for all its \$2n\$ sides, each marked with an arrow, such that identifying the sides according to this pairing and the arrow directions produces the surface (up to homeomorphism).
This pairing can be described as a cyclic *fundamental word* with two each of \$n\$ distinct symbols, where any symbol may be inverted to represent an arrow pointing opposite to the direction of travel around the polygon. For example, the word \$abab^{-1}\$ describes the Klein bottle:
[](https://en.wikipedia.org/wiki/File:KleinBottleAsSquare.svg)
In light of the [classification theorem](https://en.wikipedia.org/wiki/Surface_(topology)#Classification_of_closed_surfaces) for surfaces, which states that every closed 3D surface is homeomorphic to *either* the connect-sum of \$g\ge0\$ tori (including the sphere at \$g=0\$) *or* the connect-sum of \$k>0\$ cross-caps, it may not be immediately obvious what surface a fundamental polygon represents. Fortunately canonical forms and a canonicalisation process exist – the material below comes from Gerhard Ringel's *Map Color Theorem*.
## Canonical words for surfaces
The canonical fundamental word for the connect-sum of \$g\ge0\$ tori, with genus \$g\$, is
$$a\_1b\_1a\_1^{-1}b\_1^{-1}a\_2b\_2a\_2^{-1}b\_2^{-1}\dots a\_gb\_ga\_g^{-1}b\_g^{-1}$$
So the sphere's canonical word is the empty string, the normal torus's is \$aba^{-1}b^{-1}\$ and so on.
The canonical fundamental word for the connect-sum of \$k>0\$ cross-caps, with genus \$-k\$ (although this is incorrect, this definition is used here because then the integers bijectively correspond to surface types) is
$$a\_1a\_1a\_2a\_2\dots a\_ka\_k$$
The real projective plane and Klein bottle are the \$k=1\$ and \$k=2\$ cases of this sequence, so their canonical words are \$aa\$ and \$aabb\$ respectively.
## Canonicalisation
The surface represented by a fundamental word is unchanged if
* the word is cyclically rotated: \$aabb\to abba\$
* a symbol is inverted: \$aabb\to aab^{-1}b^{-1}\$
* a symbol and its **adjacent** inverse are cancelled: \$caba^{-1}b^{-1}c^{-1}\to aba^{-1}b^{-1}\$
The surface is orientable iff each symbol appears once inverted and once uninverted in the word. In that case a "handle" can be extracted by the following word transformation, where \$Q,R,S\$ are not all empty:
$$PaQbRa^{-1}Sb^{-1}T\to PSRQTaba^{-1}b^{-1}$$
Repeating this process with intermediate cancellation leads to the canonical form for orientable surfaces described above.
If the two occurrences of a symbol are both inverted or both uninverted, the surface is non-orientable. In this case a cross-cap may be extracted by the following word transformation, where \$Q^{-1}\$ is the group-theoretic inverse (so e.g. \$(abc)^{-1}=c^{-1}b^{-1}a^{-1}\$):
$$PaQaR\to aaPQ^{-1}R$$
Do this as many times as possible to get a word of the form \$a\_1a\_1\dots a\_ia\_iO\$, where \$O\$ is the fundamental word of an *orientable* surface. Canonicalise \$O\$ as above and determine its genus \$g\$; the canonical form of the full non-invertible surface is then \$a\_1a\_1\dots a\_{i+2g}a\_{i+2g}\$, because a handle turns into two cross-caps in the presence of another cross-cap.
## Example
This picture from one of my [MathsSE answers](https://math.stackexchange.com/a/4651117/357390) is an embedding of the [Johnson graph](https://en.wikipedia.org/wiki/Johnson_graph) \$J(5,2)\$:

The star-shaped border represents a fundamental polygon where
* each black (dark blue) arc matches the grey (light blue) arc 5 steps away going counterclockwise
* each golden yellow arc matches the light yellow arc 7 steps away going clockwise
* in all cases the matching is parallel (as hinted by the faded exterior), so the surface is orientable
Thus the corresponding fundamental word is
$$ah^{-1}bf^{-1}ca^{-1}db^{-1}ei^{-1}fd^{-1}ge^{-1}hc^{-1}ig^{-1}$$
which reduces as follows:
$$(a)h^{-1}(b)f^{-1}c(a^{-1})d(b^{-1})ei^{-1}fd^{-1}ge^{-1}hc^{-1}ig^{-1}$$
$$\to (d)f^{-1}(c)h^{-1}ei^{-1}f(d^{-1})ge^{-1}h(c^{-1})ig^{-1}aba^{-1}b^{-1}$$
$$\to ge^{-1}[hh^{-1}]ei^{-1}[ff^{-1}]ig^{-1}aba^{-1}b^{-1}dcd^{-1}c^{-1}$$
$$\to g[e^{-1}e][i^{-1}i]g^{-1}aba^{-1}b^{-1}dcd^{-1}c^{-1}$$
$$\to[gg^{-1}]aba^{-1}b^{-1}dcd^{-1}c^{-1}$$
$$\to aba^{-1}b^{-1}dcd^{-1}c^{-1}$$
Thus the surface has genus 2, which matched my expectation when I constructed the embedding based on a triangulation with 10 vertices and 36 edges – by Euler's formula such a triangular embedding, if orientable, must live on the genus-2 surface. Indeed (glue the three ends of the open surface below in a Y-shape so that the colours match):

## Task
Given a list of *nonzero integers* where the magnitudes from 1 to \$n\$ appear exactly twice each, representing a fundamental word with a negative number marking an inverted symbol, output the genus of the surface corresponding to that fundamental word, using the definition above where a negative genus \$-k\$ means "connect-sum of \$k\$ cross-caps".
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"); fewest bytes wins.
## Test cases
```
[] -> 0
[1, -1] -> 0
[1, 1] -> -1
[1, 2, -2, -1] -> 0
[1, 2, -1, -2] -> 1
[1, 2, 1, -2] -> -2
[1, 2, 1, 2] -> -1
[-2, -2, -1, 1] -> -1
[1, 2, 3, -1, -2, -3] -> 1
[-3, 1, 3, -2, 1, 2] -> -2
[1, 2, 3, 4, -1, -2, -3, -4] -> 2
[1, 2, 4, 4, -2, -3, 1, -3] -> -2
[1, -8, 2, -6, 3, -1, 4, -2, 5, -9, 6, -4, 7, -5, 8, -3, 9, -7] -> 2
[1, -8, 2, -9, 3, -1, 4, -2, 5, -3, 6, -4, 7, -5, 8, -6, 9, -7] -> 3
[4, 3, 2, 1, 1, 2, 3, 4] -> -4
[3, 4, 1, 2, 6, 7, -4, 5, -2, -3, -7, -1, -5, -6] -> 3
[1, 2, 3, 3, -1, -2] -> -3
```
[Answer]
# [Curry (PAKCS)](https://www.informatik.uni-kiel.de/%7Epakcs/index.html), 159 bytes
```
f[]=0
f(p++a:b:q)|a+b==0=f$p++q
f(p++a:q++a:r)=g$f$p++reverse[-x|x<-q]++r
f(p++a:q++b:r++c:s++d:t)=(a+c)!(b+d)$f$p++s++r++q++t
g x=min(-2*x)x-1
(0!0)x|x>=0=x+1
```
[Attempt This Online!](https://ato.pxeger.com/run?1=TY9NCoMwEIX3niKCi6RjINpNCU0vIlLiT0SKYqKWFLxJF3XTVc_Qg_Q2TRWhMAzMe98Mb-6vfDTmdu7kJe_n-TkOih4-D5WkgnkKdwCSZ1yTSUImBBMqcJLeHP1rhogqWHRTXkvTlwm1kz1SnTrlj8y4Ach5D1DwgQgsISc-zqAg67YzHODAwauQFU3dYhrvLLE08jDzGXFXTy6ChWiN-W5k3SKBFEqiEMUh2i9F3UDjdGW2l74)
[Answer]
# [Vyxal](https://github.com/Vyxal/Vyxal), ~~56~~ ~~49~~ 46 bytes
```
(ṫ~c[€ɖ‡ṘNf&›|p;ȧ:(ṫ€:ḣt↔h:ḃ∇v€ÞfḣṘJf)W∑¥[d¥+N
```
[Try it Online!](https://vyxal.pythonanywhere.com/#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)
First we extract all cross-caps. This is done by looking at the last symbol. If it occurs in the same orientation twice, the cross-cap is extracted by taking a word \$PaQa\$ and transforming it into \$PQ^{-1}\$, incrementing the register each time it happens. Otherwise the word is rotated to the left. This is repeated as many times as the number of symbols in the input.
```
(ṫ~c[€ɖ‡ṘNf&›|p;
( ; # run the following once for each symbol in the input:
[1, 2, 3, 1, -2, 3]
ṫ # tail extract [1, 2, 3, 1, -2], 3
~c # contains? without popping [1, 2, 3, 1, -2], 3, 1
[ # if:
€ # split on [[1, 2], [1, -2]]
ɖ‡-- # apply the following to the second item:
ṘN # reverse and negate
[[1, 2], [2, -1]]
f # flatten [1, 2, 2, -1]
&› # increment register
| # else:
p # prepend
```
Now we are left with a word of an orientable surface so we can forget which symbols are inverted.
Now we extract handles and remove adjacent inverses. This is done by looking at the last symbol. We write the word as \$PaQa\$. If there is a common symbol in \$P\$ and \$Q\$ there exists a handle \$RbSaTbUa\$ so we transform the word into \$RUTS\$, leaving a 1 on the stack each time it happens. If there are no common symbols in \$P\$ and \$Q\$ then \$a\$ will eventually become adjacent with itself so we can delete it, leaving a 0 on the stack each time it happens. This is repeated as many times as the number symbols left in the word after extracting cross-caps.
```
ȧ:(ṫ€:ḣt↔h:ḃ∇v€ÞfḣṘJf)
ȧ # absolute value
:( ) # run the following once for each symbol in the word:
ṫ # tail extract
€ # split on
: # duplicate
ḣ # head extract
t # tail
↔ # intersection
h # head
: # duplicate
ḃ # boolify
∇ # shift (leave it on the stack for later)
v€ # vectorise split on
Þf # flatten by one level
ḣ # head extract
Ṙ # reverse
Jf # join and flatten
```
All that's left is to combine the number of cross-caps extracted and number of handles extracted.
```
W∑¥[d¥+N
W # wrap stack in a list
∑ # sum
¥[ # if register is non-zero
d # double
¥+ # add register
N # negate
```
] |
[Question]
[
### Background
Math SE's HNQ [How to straighten a parabola?](https://math.stackexchange.com/q/4209381/284619) has 4,000+ views, ~60 up votes, 16 bookmarks and six answers so far and has a related companion HNQ in Mathematica SE [How to straighten a curve?](https://mathematica.stackexchange.com/q/251570/47301) which includes a second part asking to move a point cloud along with the curve that we can ignore here.
From the Math SE question:
>
> Consider the function \$f(x)=a\_0x^2\$ for some \$a\_0\in \mathbb{R}^+\$. Take \$x\_0\in\mathbb{R}^+\$ so that the arc length \$L\$ between \$(0,0)\$ and \$(x\_0,f(x\_0))\$ is fixed. Given a different arbitrary \$a\_1\$, how does one find the point \$(x\_1,y\_1)\$ so that the arc length is the same?
>
>
> Schematically,
>
>
> [](https://i.stack.imgur.com/djrlsm.png)
>
>
> In other words, I'm looking for a function \$g:\mathbb{R}^3\to\mathbb{R}\$, \$g(a\_0,a\_1,x\_0)\$, that takes an initial fixed quadratic coefficient \$a\_0\$ and point and returns the corresponding point after "straightening" via the new coefficient \$a\_1\$, keeping the arc length with respect to \$(0,0)\$. Note that the \$y\$ coordinates are simply given by \$y\_0=f(x\_0)\$ and \$y\_1=a\_1x\_1^2\$.
>
>
> [](https://i.stack.imgur.com/x7o8V.gif)
>
>
>
### Problem
Given a positive integer n and values a0 and a1 defining the original and new parabolas:
1. Generate \$n\$ equally spaced values for \$x\_0\$ from 0 to 1 and corresponding \$y\_0\$ values.
2. Calculate the new \$x\_1\$ and \$y\_1\$ such that their path distances along the new parabola are equal to their old distances.
3. Output the \$x\_0\$, \$x\_1\$ and \$y\_1\$ lists so that a user could plot the two parabolas.
**note:** The basis of the calculation can come from any of the answers to either linked question or something totally different. If you choose to use a numerical rather than analytical solution an error of \$1 \times 10^{-3}\$ would be sufficient for the user to make their plot.
Regular Code Golf; goal is shortest answer.
### Example
This is quite a bit late but here is an example calculation and results. I chose the same numbers as in Eta's [answer](https://codegolf.stackexchange.com/a/233178/85527) in order to check my math.
[](https://i.stack.imgur.com/IVGDF.png)
```
s0: [0.00000, 0.13589, 0.32491, 0.59085, 0.94211, 1.38218, 1.91278, 2.53486, 3.24903]
x0: [0.00000, 0.12500, 0.25000, 0.37500, 0.50000, 0.62500, 0.75000, 0.87500, 1.00000]
x1: [0.00000, 0.13248, 0.29124, 0.46652, 0.64682, 0.82802, 1.00900, 1.18950, 1.36954]
```
script:
```
import numpy as np
import matplotlib.pyplot as plt
from scipy.optimize import root
def get_lengths(x, a): # https://www.wolframalpha.com/input?i=integrate+sqrt%281%2B4+a%5E2x%5E2%29+x%3D0+to+1
return 0.5 * x * np.sqrt(4 * a**2 * x**2 + 1) + (np.arcsinh(2 * a * x)) / (4 * a)
def mini_me(x, a, targets):
return get_lengths(x, a) - targets
a0, a1 = 3, 1.5
x0 = np.arange(9)/8
lengths_0 = get_lengths(x0, a0)
wow = root(mini_me, x0.copy(), args=(a1, lengths_0))
x1 = wow.x
fig, ax = plt.subplots(1, 1)
y0, y1 = a0 * x0**2, a1 * x1**2
ax.plot(x0, y0, '-')
ax.plot(x0, y0, 'ok')
ax.plot(x1, y1, '-')
ax.plot(x1, y1, 'ok')
np.set_printoptions(precision=5, floatmode='fixed')
things = [str(q).replace(' ', ', ') for q in (lengths_0, x0, x1)]
names = [q + ': ' for q in ('s0', 'x0', 'x1')]
for name, thing in zip(names, things):
print(' ' + name + thing)
_, ymax = ax.get_ylim()
xmin, _ = ax.get_xlim()
ax.text(x0[-1:]+0.03, y0[-1:]-0.1, str(a0) + 'x²')
ax.text(x1[-1:]-0.04, y1[-1:]-0.1, str(a1) + 'x²', horizontalalignment='right')
title = '\n'.join([name + thing for (name, thing) in zip(names, things)])
ax.set_title(title, fontsize=9)
plt.show()
```
[Answer]
# Mathematica, ~~108~~ 107 bytes
```
{n,a,b}=Input[];L=ArcLength;Subdivide@--n
x/.FindRoot[{t,t^2a}~L~{t,0,#}-{t,t^2b}~L~{t,0,x},{x,0}]&/@%
%^2b
```
(Assuming an interactive environment). Input is entered in the form `{n, a0, a1}`.
Below is the output of a sample run with input `{9, 3, 1.5}`:
```
{0, 1/8, 1/4, 3/8, 1/2, 5/8, 3/4, 7/8, 1}
{0., 0.13247799662957596, 0.2912428843578418, 0.4665152489073556, 0.6468180849532895, 0.8280191118364263, 1.0089961907516996, 1.189503180997409, 1.369535545562379}
{0., 0.026325629386478908, 0.1272336265336128, 0.3264547161946379, 0.6275604525339613, 1.0284234743495764, 1.5271099694271602, 2.122376726404432, 2.8134414158382643}
```
## Explanation
This uses `FindRoot` to find `x`s where the `ArcLength` of the original equation to each point in x0 matches the `ArcLength` of the flattened equation up to each `x`.
Here is a visualization of the points in the example:
[](https://i.stack.imgur.com/mioc0.png)
With the (identical) corresponding arc lengths at each point:
```
{0., 0.1358872650466621, 0.32491055615709175, 0.5908450391982809, 0.9421066199781004, 1.3821781999397988, 1.9127768947936938, 2.534864156640448, 3.249029586202852}
```
] |
[Question]
[
[Sandbox](https://codegolf.meta.stackexchange.com/a/22322/80214)
Inspired by a [Codingame](https://codingame.com/) challenge I tried (and failed at) about a month ago.
Given a binary tree of words, say:
```
HELLO
/ \
WORLD EATING
/ / \
ARCH IDAHO GUARD
/
DOOZY
/
ZEPPELIN
/ \
POWER LIGHT
```
1. Take the root of the tree.
2. Print it in the South direction.
```
H
E
L
L
O
```
3. For each of the tree's children, given iteration index i:
1. Find the first character in the child that it has in common with the root. If there are multiple occurrences of that character in the root, choose the first occurrence as the join point.
2. The drawn root word will have to intersect the child at this point.
3. Draw the left node down to the left, and the right node down to the right.
```
H
E
LA
LWT
O I
R N
L G
D
```
4. Now, for each of the diagonal words' children, do the same, except always print downward.
```
H
E
LA
LWT
AO I
R DN
LC A G
D H H U
O A
R
D
```
5. Go back to step3 and perform the steps again until the tree is complete.
```
H
E
LA
LWT
AO I
R DN
LC A G
D H H U
O A
R
D
O
O
Z
YE
P
OP
W E
E L
R II
N G
H
T
```
## Clarifications
* No two child words will have the same first common letter.
* Words from different subtrees will never intersect.
* Input will always be a valid binary tree.
* Each parent will always have a common character with both of its children.
* Trees can be taken in any suitable and reasonable format for your language.
* Leading and trailing whitespace is allowed, so long as the structure of the lightning is as shown.
* All words will be given in the same case.
# Testcases
```
PROGRAMMING
|
CHALLENGES
| \
PUZZLES CODING
```
```
P
R
PO
UG C
ZRHO
ZA D
LM I
LEM N
E SI G
N N
G G
E
S
```
---
```
DIGERIDOO
| \
GIRDLE ORNATE
| | \
EXQUISITE ROLL TALONS
| \
QUEEN TAPESTRY
| \
PASTE YELLOW
|
ERROR
```
```
D
I
G
IE
R R
D I
L D
E O
X OR
Q ON
UU L A
E I L T
E S AE
N I L
T O
EA N
P P S
EA
S
TT
E R
R Y
R E
O L
R L
O
W
```
[Answer]
# [Charcoal](https://github.com/somebody1234/Charcoal), 88 bytes
```
↓§θ⁰⊞υ⁺E³¦⁰θFυ«≔¬§ι⁰ηFΦι›λ³«≔§κ⁰ζ≔§Φζ№§ι³λ⁰εJ§ι¹§ι²M⌕§ι³ε✳⁻⁶§ι⁰M⌕ζε✳⁻²η⊞υ⁺⟦ηⅈⅉ⟧κ✳⁻⁶ηζ≦±η
```
[Try it online!](https://tio.run/##bZFfa8IwFMWf56cIfUogg01hD9tTWTPpqE1NK1OKD0UzW@wS7R83HH72LknbbYoPgXtzz/ldcrJKk2Ilk7xpgiITFXx05KfAwK5cseZfcI/BHUJPg6AuU1hjEOR1CSfJDo70AIO9Hr7LAsAage/BjV2W2UZAX1awR2QGgUGqlDdG@pLlFS/0YFzwRJc5BiOEDKFH9PZtu@io3ZezDnTE4FnW4mzlSHlyvVabuTG/1h@7SP4X3aO/l6p2iIxuIg9cocX6ksfVcbKCr6pMCjjJhMri4YygHnrJOF73DXUgrfYs2zjFYA6VYQHREoNtJzF/c2V3in6zUb/Sp883KtUu8dPg1DRxbDnumDDXodTCILbGLnM8Ykoyn87c0I3abjojxLeWuozsgIQRW5j7wA47BWGMMmtpJAviefRNNW1LmW93KkY9r8d41A@Nprk95D8 "Charcoal – Try It Online") Link is to verbose version of code. Explanation:
```
↓§θ⁰
```
Print the first word vertically.
```
⊞υ⁺E³¦⁰θFυ«
```
Start a breadth-first traversal of the tree, but prefixing three status variables to each entry for the coordinates and the direction.
```
≔¬§ι⁰η
```
Get the direction of the previously printed word and flip it to 0 (which will become downwards) if it was non-zero or 1 (which will become down left) if it was zero.
```
FΦι›λ³«
```
Loop over any child nodes.
```
≔§κ⁰ζ
```
Get the current node's word.
```
≔§Φζ№§ι³λ⁰ε
```
Find the first letter in its word that's shared with its parent's word.
```
J§ι¹§ι²M⌕§ι³ε✳⁻⁶§ι⁰M⌕ζε✳⁻²η
```
Jump to the parent's start, then move to the parent's shared letter, then work back to where this branch's word needs to start.
```
⊞υ⁺⟦ηⅈⅉ⟧κ
```
Concatenate this word's position and direction with the node and push that to the list of nodes to traverse.
```
✳⁻⁶ηζ
```
Print the node's word in the appropriate direction.
```
≦±η
```
Flip the direction in case this word was printed down left and there's a sibling node still to print.
] |
[Question]
[
In this challenge, your task is to detect (vertical) *Skewer Symmetry*. This means that one half of the pattern can be produced by mirroring the other half along a vertical axis, and then moving it vertically.
For example, the following pattern has skewer symmetry:
```
asdf
jkl;fdsa
;lkj
```
Because if you start from the left half...
```
asdf
jkl;
```
...then mirror it along a vertical axis...
```
fdsa
;lkj
```
...then move it down by a character (filling the empty rows with spaces)...
```
fdsa
;lkj
```
...you get the second half.
## Rules:
* You may assume the input is rectangle and has an even number of columns.
* If the pattern itself exhibits reflection symmetry, it is considered skewer symmetry.
* This is strict character by character symmetry, so `[[` is considered symmetrical, but not `[]`.
* You should output truthy if the input has skewer symmetry, falsy otherwise.
* Default I/O rules apply, standard loopholes are banned.
## Test Cases
Truthy cases:
```
asdf
jkl;fdsa
;lkj
```
```
asdffdsa
```
```
[
[
```
```
ba
abdc
cd
```
Falsy cases:
```
[
]
```
```
ab
ba
```
```
aa
a
a
```
```
a a
b b
```
```
ab
b
a
```
[Answer]
# [APL (Dyalog Unicode)](https://www.dyalog.com/), ~~44~~ 34 bytes[SBCS](https://en.wikipedia.org/wiki/SBCS)
[crossed out ~~44~~ is still regular 44 ;(](https://codegolf.stackexchange.com/q/170188/75323)
Hats off to @Bubbler, @ngn and @TesselatingHeckler as they managed to shave some bytes off of my solution, more or less independently but coming up with the same simplifications.
```
{1∊(l↓⍵)⍷⍨a/⍨∨⌿' '≠a←⊖⍵↑⍨l←2÷⍨≢⍵}⍉
```
[Try it online!](https://tio.run/##SyzI0U2pTMzJT///v9rwUUeXRs6jtsmPerdqPurd/qh3RTWQqQ@kH3WseNSzX11B/VHnAqBQ7aOuaUDqUdtEoBxQxwSjwyDVjzoXgSV7O/@nKQBFFaqB@vR1qGQmF9ejvqlAcaDRYFrBWMHiUe8W9cTilDQFIMjKzrFOSylOBLGtc7Kz1NHVGyLUg9SpY5pnApJXUEhMSkpMSU5OUVCAqVFQx1BtpGAENg2oFpdJiUkgt4CJRPX/AA "APL (Dyalog Unicode) – Try It Online")
Now I'll explain **how it works**:
```
{ }⍉ ⍝ We define a monadic function that we apply right after transposing (⍉) the input [this means we will be operating on columns instead of rows]
2÷⍨≢⍵ ⍝ Start by finding how many columns the input has (≢),split that in half (2÷⍨)
l← ⍝ and assign that to l (l←) ...
⍵↑⍨ ⍝ Using it right away to take (↑⍨) l columns from the original input ⍵
⊖ ⍝ which we then reverse (⊖) [effectively flipping the columns upside down]
a← ⍝ and assign to a (a←)
' '≠ ⍝ We then compare each character in a to ' '
∨⌿ ⍝ and we "interleave" the logical OR (∨) over the columns (⌿) [to find columns where at least one character is different from ' ']
a/⍨ ⍝ finally selecting those columns from a (a/⍨)
⍷⍨ ⍝ Now we superimpose that piece of the original character matrix over all possible locations
(l↓⍵) ⍝ of the columns of ⍵ that remain after we drop (↓) the first l columns [i.e. we take the second half of the columns]
1∊ ⍝ and we look for matches by checking if there is a 1 (Truthy) in any position (∊)
```
[Answer]
# [J](http://jsoftware.com/), ~~34~~ ~~23~~ 38 bytes
```
1 e.[:(e.&:((-:@#{.])"1)|."1\.)"2],:|.
```
[Try it online!](https://tio.run/##bZBRa4MwFIXf/RUHO3oVNKu2DyPB0TE2GOxprzaMxESKla2ghcH6311ifZilF0LCyXfuudxmCBnVKDgICVbg7qQMzx/vr0MGy0oeWbbkUZTy7eKXyTjM4jMLsx2Lw1wm/MyGOLDV/hs11tjgzvWBVkqbqjIABUFvu75gkKIU9VYGgSkY0XgZl5hBON@D96nO1HDVHFpRm075t2gPDf1nE34BPTD72CD3TUqMVdI84NZgE7ByQD6Z01TSDV1prWb6etKVG1JdOcYor2toH3PZTkRvX8dTT4Jefo626q0hAXqq@pNqKXbmzxx@U8vH@x3M8Ac "J – Try It Online")
*thanks to nimi for catching a bug*
Will attempt to regolf the fixed version later.
[Answer]
## Haskell, ~~137~~ ~~135~~ 133 bytes
```
f s=uncurry(#)$unzip$splitAt(div(length$s!!0)2)<$>s
a#b@(x:y)|e$last a++x=init a#y|e$last b++a!!0=b#a|r<-reverse<$>b=a==r
e=all(<'!')
```
[Try it online!](https://tio.run/##TYxLTsMwEIb3OcXkIdVWCkIsaYzgAJwgitBM7FA3rhXZTtWg3j04EQ14MZ75/scRfa@MmecOvBhtOzo3sZwXo/3WQ@EHo8N7YFJfmFH2KxwLn6ZP/JlXxatPMKc3dn2Z@E0VBn0ALMur0FbHLZ/ukMoSY0hQjjdXPTh1Uc6rWEAChXCJEmgMq3bpjs9n1BYEnHH4@AQ2OG0DPHYc6gSgztDLDuLL9tmpN4dOeozrQg6mP2XNfnOt0u9dw2paRn1nALREkWQbv1ZGOSr/7M3WRvGkrQzX2Gr5YwALJaDY0iTzDw "Haskell – Try It Online")
] |
[Question]
[
## Background
**[Tatamibari](https://en.wikipedia.org/wiki/Tatamibari)** is a logic puzzle designed by Nikoli.
A Tatamibari puzzle is played on a rectangular grid with three different kinds of symbols in it: `+`, `-`. and `|`. The solver must partition the grid into rectangular or square regions according to the following rules:
* Every partition must contain exactly one symbol in it.
* A `+` symbol must be contained in a square.
* A `|` symbol must be contained in a rectangle with a greater height than width.
* A `-` symbol must be contained in a rectangle with a greater width than height.
* Four pieces may never share the same corner. (This is how Japanese tatami tiles are usually placed.)
The following is an example puzzle, with a solution:
[](https://i.stack.imgur.com/UGBks.png) [](https://i.stack.imgur.com/STEe0.png)
## Task
Solve the given Tatamibari puzzle.
## Input & output
The input is a 2D grid that represents the given Tatamibari puzzle. Each cell contains one of the four characters: `+`, `-`, `|`, and a character of your choice to represent a non-clue cell. In the test cases, an asterisk `*` is used.
You can choose any suitable output format which can unambiguously represent any valid solution to a Tatamibari puzzle. This includes, but is not limited to: (if in doubt, ask in comments.)
* A list of 4-tuples, where each tuple includes the top index, left index, width and height of a rectangle (or any equivalent representation)
* A numeric grid of the same shape as the input, where each number represents a rectangle
* A list of coordinate sets, where each set includes all the coordinates of the cells in a rectangle
If a puzzle has multiple solutions, you can output any number (one or more) of its valid solutions. The input is guaranteed to have at least one solution.
## Test cases
```
Puzzle:
|-*
*+|
*-*
Solution:
122
134
554
=====
Puzzle:
+***
**|*
*+**
***-
Solution:
1122
1122
3322
3344
======
Puzzle:
|*+*+
*****
****-
***+|
+****
Solution:
12233
12233
44444
55667
55667
=======
Puzzle:
****-**
**-**|*
*|*****
****-**
*******
**+*|**
*****+*
One possible solution:
1122222
1133344
1155544
1155544
6667744
6667788
6667788
===========
Puzzle:
*-****|+**
+*-******|
****+*****
*-******||
**++|*****
+****-|***
-****-**+*
********-*
|*+*+|****
*-*--**+*+
Solution:
1111122334
5666622334
7777822994
7777A2299B
CCDEA2299B
CCFFFFGGHH
IIIIJJGGHH
KLLMMNGGOO
KLLMMNGGPP
QQRRSSSTPP
```
## Rules
Standard [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'") rules apply. The shortest code in bytes wins.
[Answer]
# [Python 2](https://docs.python.org/2/), ~~417~~ ~~374~~ 366 bytes
Input is list of lines, `~` for non-clue.
Outputs a single solution to stderr in the format `(x_start, width, y_start, height)`.
```
R=range
k=input()
X,Y=len(k[0]),len(k)
W,H=R(X),R(Y)
Q=[[]]
for q in Q:C=[(x,y)for(a,b,c,d)in q for x in(a,a+b)for y in(c,c+d)];max(map(C.count,C+W))<4>0<all(sum(w>x-s>-1<y-t<h<[c for r in k[t:t+h]for c in r[s:s+w]if'~'>c]==['+|-'[cmp(h,w)]]for(s,w,t,h)in q)==1for x in W for y in H)>exit(q);Q+=[q+[(s,w+1,t,h+1)]for s in W for w in R(X-s)for t in H for h in R(Y-t)]
```
[Try it online!](https://tio.run/##RVDBbuIwEL37KywueGRnRdI9hTgXLr2CVqLI8sEYt44IToiNkkiIX6dxKraSNZp5b96b8bRjsI3Lns8d75T7MujMK9feAgH0wQ68No6cxUoCmzNAe/bOd@QD2I4cAG25EFKiz6bDV1w5vM03XJCBjTBBRLEj0@wEE3HFsWeYeiZU0WPk8RhLzTQ9gVxf1EAuqiWbP7q5ucA2dA9Q/C1Xhapr4m8X0pdD4sskLcYkFLYQevbs4tyzCHmgVkZAR6ATPve0l9Xn8rEsteRcLOk9WQp9aYllPcjYSzzrWWB23hA4T19L4j1@LYjfoTRDFcgV1lvKxZWKKKNpFNIU5pn@V9PHdLpQ4uc/htliZuwPc0gCyOdzQR8LtqD3BUL/bBUNpqvjzrSd8cYFnyP6QPSOUG8rbbFWDh8NblUXqsaZU/QK1kzGdd30lfvCvRpzlGboLUMozTFZMZwyHCOgbKrTV50BevvPxwff "Python 2 – Try It Online") This is too inefficient for the suggested test cases.
---
## Ungolfed
```
grid = input()
total_width = len(grid[0])
total_height = len(grid)
partitions = [[]]
for partition in partitions:
# list the corners of all rectangles in the current partition
corners = [(x, y)
for (start_x, width, start_y, height) in partition
for x in (start_x, start_x + width)
for y in (start_y, start_y + height)]
# if no corners appears more than three times ...
if corners != [] and max(map(corners.count, corners)) < 4:
# .. and all fields are covered by a single rectangle ...
if all(
sum(width > x - start_x > -1 < y - start_y < height
for (start_x, width, start_y, height) in partition) == 1
for x in range(total_width)
for y in range(total_height)):
# ... and all rectangles contain a single non-~
# symbol that matches their shape:
if all(
[char for row in grid[start_y: start_y + height]
for char in row[start_x:start_x + width] if '~' > char]
== ['+|-'[cmp(height, width)]]
for (start_x, width, start_y, height) in partition):
# output the current partition and stop the program
exit(partition)
# append each possible rectangle in the grid to the current partition,
# and add each new partition to the list of partitions.
partitions += [partition + [(start_x, width + 1, start_y, height + 1)]
for start_x in range(total_width)
for width in range(total_width - start_x)
for start_y in range(total_height)
for height in range(total_height - start_y)]
```
[Try it online!](https://tio.run/##rVXbjtowEH33V0zhgVgJaGH7FJX9ir6haGWCIZYSO7JNQ6QVv07HiXMBQlVVRQhie85czvFMytpmSm5ut5MWB9iCkOXZBpRYZVn@WYmDzXA35zJwBru3pDvKuDhldnRGCSmZtsIKJQ3u73ZJQshRaei30fuwMDEB/MwhF8aCzTikSkuuDagjsDwHzVPL5CnnxuEag7PWXNrBR@Ohg2HI4BJBTZvd0cflEBiLoE88b2qKoF3XEbSF0LvcpjxcnMXgxj9A2DqcDFqPIHUfEiE@ZuIZEEeQqq@DlSVn@F8ozbFs5mrXHB9FgVSsVqsGhZgO8A0rT4DJAxTsEhSsDPzJKlVnaaPOkFL4Ad/jPtM5Omtgju2j4PkBg2unwy@u@QH2NTAwwkkwiNEn4JNAbPBYO5hzEbR35wN5W/ZkfcByjTnU/VaNq5aMJx//phyF7RbWBF4JqLEIHoxuN520rR9tfSwa35k7BgcKRxc2VdIydNHzJ5VcXh@wpi72KncSW1TOphkC8ZoLDSZjJb8P9YrqXZox3eSsVeWybvrUcxQ/3bnkJc@NH1e1qjz8Ej9c8sRlsbguUEdn/ewLud8twq/lYpcWZdBG9LrRJPlfEsdPjuagzhYH1/SUaAQyVpXNcanVSbPiyQe/CBsMQYjvTdeNCOcszaBUxoj9XTf4ydRMT6um40edK3dPDt6X5NUoQw9tRiGOv2FItr02GqwhUjzgQpx59@Th1vqJQLdJJ/l39Hcq/117eFAbbAoy9Dv9c8RXTfYK5WuZBA0TBeu83WbhdRbNwq8ZIT8zYdrXGspWam5QG3z3hFcSfhFSZQLFSHHI7nlLs5I4@rysR5XnqsIOhorVMVlvyPuGkHUMwVvkaHa/lGxwve7WG0re@3P3pb8B "Python 2 – Try It Online")
[Answer]
# [J](http://jsoftware.com/), 193 bytes
Returns all possible solutions as grids with -1, -2 … indicating rooms. There is room for improvements, but the `((((((` started to confuse me. :-)
```
[:(#~0=0(e.,)"2])'*+-|'([:,/(([(<./@,@:<:@[`]`[}{.<@:+"1,/@(#:i.)@{:)"2((((({(0,=/,</,>/)@$)~0({.*(1=#)*0<{.)@-.~,);.0~*[:*/0<1{])"2#]){.([,:-~)"1/>:))[(#~0<:,)~,/@(#:i.)@$)"2)^:(1#.*@,)@,:@i.]
```
[Try it online!](https://tio.run/##1ZHLTsMwEEX3/gqrqZQZv9PlNKksIbFixdYKVEKtKBs@wCa/HmynhSIeeyIl9ozPvTMTv8wr0x75QLzlijtO@dWG39zf3c6BoJnc4OBgFK42I7ZC6tRCIGUBAvTGeuWpJx/24z68RdN7kqtOWQ8NnQz6SFkH5Yng1GBVb9XOol/j5CAaAd3QoHB9zKw2k8KtcZMIJKzruzhmcTNiNBAU6QlXnd0RYihd9aRw@iy0zig@EHSNEV6hV@RPZpyRsWMd7vdRcr4TvjHJq2zxb0ZjjB2enl85bLU/Ig9b87jhUO8PWdKCCZmYyCv@BUohMilSwetO6L8FKXOycAud8fzJlWTNfJF@01a@6vRSMl35nNclluVoieW1a@d4NPxHb13gVIaQyz5HbDFYTC/JkpXyXLoe6hIwfW5DfjRS/l6dN10cdD2XDOd3 "J – Try It Online") For the larger test cases I provided `ff` that has a filter `[:(#~1*@#.|@,"2)` for intermediate steps, where empty grids got added because of padding.
### How it works
* `'*+-|' … i.]` Map `*+-|` to `0 1 2 3`.
* `,/@(#:i.)@$` From all the tiles
* `[(#~0<:,)~` that aren't part of a room,
* `{.([,:-~)"1/>:` starting from the most top-left tile, that isn't part of a room yet, try every possible rectangle spanning down-right.
* `…"2#]` For that rectangle to be valid for the next step,
* `[:*/0<1{]` 0.) it must have a positive size in each dimension
* `0({.*(1=#)*0<{.)@-.~,` 1.) no tile must be part of a room, 2.) exactly one symbol must be within the rectangle,
* `(({(0,=/,</,>/)@$)~` 3.) the dimension of the rectangle fulfill the constraint of the symbol.
* `(<./@,@:<:@[`]`[}{.<@:+"1,/@(#:i.)@{:)"2` For every valid rectangle, copy the current grid and place the next room.
* `^:(1#.*@,)@,:` We need to do this `n` times, where `n` is the number of symbols.
* `[:(#~0=0(e.,)"2])` After this there might be grids that have `n` rooms, but still empty tiles; those must be filtered out.
] |
[Question]
[
Write an indefinitely-running program that reports how many instances of itself are currently running. Each instance of the program should also report the order in which it was opened out of all other currently-running instances.
## Example
The user launches the program for the first time - we'll call this Instance 1. Instance 1 displays `1/1`, because it is the **first** instance to be launched out of a total of **1** currently-running instances.
While Instance 1 is running, the user launches the program a second time to become Instance 2. Instance 1 now displays `1/2`, being the **first** instance out of a total of **2** currently-running instances. Instance 2 displays `2/2`, because it is the **second** instance out of a total of **2** currently-running instances.
Let's say the user continues to spawn more instances until there are **5** of them. In order of launch, their outputs are: `1/5` `2/5` `3/5` `4/5` `5/5`.
Now, let's say the user decides to terminate Instance 3. Instance 4 then becomes the new Instance 3 and Instance 5 the new Instance 4, because they are respectively the **third** and **fourth** instances to have been launched out of what is now a total of **4** instances. So each instance's change in output would be as follows:
* `1/5` → `1/4`
* `2/5` → `2/4`
* `3/5` → (Terminated)
* `4/5` → `3/4`
* `5/5` → `4/4`
## Rules
* You may output the two numbers (instance number, total instances) in any reasonable format.
* Whenever an instance is launched or terminated, all other instances must update their respective outputs within 100 milliseconds.
* If you choose to update output by printing to a new line (or other "appending" output format; as opposed to replacement), you must print only when the number of instances changes, and not at any other time.
* This is code golf. Shortest program in bytes wins.
* In your answer, you are encouraged to specify what the user must do to open more than one instance, and/or record a screencast to demonstrate.
[Answer]
# [APL (Dyalog Unicode)](https://www.dyalog.com/), 39 bytesSBCS
Anonymous prefix function. Call by spawning on the dummy argument `⍬` (empty numeric vector), i.e. `f&⍬`. Query currently running threads with `⎕TNUMS` and kill one or more threads with `⎕TKILL n`. Threads output changes in [own number, total number] as soon as they get processor time, i.e. pretty much instantly.
```
{⍵≡n←n[⍋n←⎕TNUMS~0]:∇n⋄∇n⊣⎕←n⍳⎕TID,⊢/n}
```
[Try it online!](https://tio.run/##SyzI0U2pTMzJT///P@1R24TqR71bH3UuzAMy86If9XaDGI/6pob4hfoG1xnEWj3qaM971N0CproWA2VACh/1bgap8XTRedS1SD@v9v9/9eCCxPK8zLx0hbTMslSF8sySDAUDPUOF4tTk/LwUhcy8ktSissScYit1rjS1R71ruID6XXxASijmq3tn5uSAbC7JyCxKAVoAcpq3p4@PgjEA "APL (Dyalog Unicode) – Try It Online")
`{`…`}` anonymous lambda where `⍵` is the argument (initially `⍬`, the empty numeric vector)
`n[`…`]` index `n` (to be defined) with:
`⎕TNUMS~0` all **T**hread **Num**bers except number `0` (the REPL)
`n←` store as `n`
`⍋` permutation which would sort ascending
now we have the active threads in order
`⍵≡` if the argument is identical to that…
`:` then:
`∇⍵` tail recurse on the argument
`⋄` else:
`⊢/n` the rightmost thread number
`⎕TID,` this **T**hread's **ID** (thread number) prepended to that
`n⍳` find the **ɩ**ndices of those two
`⎕←` print that to STDOUT
`n⊣` discard that in favour of `n`
`∇` recurse on that
[Answer]
# Python 3, ~~694~~ 691 bytes
# main.py
```
from requests import post as u
from _thread import*
import os
os.system("start cmd /C python s")
def l():
def p(q):
while 1:print(u(*q).text,end="\r")
q=['http://localhost']
q+=[u(q[0],'*').text]
start_new_thread(p,(q,))
input()
u(q[0],'-'+q[1])
while 1:
try:l();break
except:0
```
# s (short for server.py)
```
from bottle import*
from requests import post as q
try:
q("http://localhost")
except:
ids=["0"]
@post('/')
def _():
content = request.body.read().decode('utf-8')
if len(content)==0:return""
if content[0]=="*":ids.append(str(int(ids[-1])+1));return str(ids[-1])
elif content[0]=="-":del ids[ids.index(content[1:])]
else:return str(ids.index(content)) + "/" + str(len(ids)-1)
run(port="80")
```
# Why is it so long?
Unfortunately, this functionality doesn't seem to be built into Python. I was tempted to use multiprocessing, but that didn't quite seem to be the right fit for what we're doing (letting a user open a program from anywhere).
So, I took the advice of a StackOverflow post I saw (I misplaced the link) and I implemented it using `bottle`. (I am open to new suggestions).
I used the Bottle library to run my own mini http server so all the different instances can communicate with each other. I suppose I could have used a socket, although I'm not convinced that would have reduced the byte count.
I have two seperate files, `s` and `main.py`. `s` is short of server and because it appears in the code, I figured I should make the name as short as possible.
# Communication Web Server's API
The web server only accepts POST requests and only responds to input inside the POST's body.
All requests go through `/` (or `localhost/`).
Valid input:
* `*` in the post body will request for the server to return a new id to assign the client.
* `-<id>` in the post body will remove the id from the active list of id's, decreasing all relevant id's and the total count.
* An empty request in the post body will simply return an empty string. This is what is used for testing to see if the server is online.
# Closing the program
I implemented multi-threading so closing the program is as simple as pressing enter.
# Opening the program
If you do not have Python setup correctly inside your environmental variables simply create a `.bat` file and put it in the same folder as `main.py` and `s` with the following code (if you installed Python for all users, it may be at a different location):
```
set PATH=%userprofile%\AppData\Local\Programs\Python\Python36
python main.py
```
# Credits
From 694 to 691 bytes [Adám](https://codegolf.stackexchange.com/users/43319/ad%C3%A1m).
[Answer]
# sh + linux/unix tools, 128 bytes
if sleep supports floating point numbers
```
trap '(flock 9;grep -vw $$ p>t;mv t p)9>l' exit;(flock 9;echo $$>>p)9>l;f(){ echo $(sed -n /^$$\$/= p)/$(wc -l<p);sleep .1;f;};f
```
otherwise, 159 bytes
```
trap '(flock 9;grep -vw $$ p>t;mv t p)9>l' exit;(flock 9;echo $$>>p)9>l;perl -MTime::HiRes=usleep -nE/^$$'$/&&say("$./",$.+(@a=<>)),usleep 1e5,$.=-(@ARGV=p)' p
```
or sleep can be replaced with `:` (no-op), but it will make active waiting.
[Answer]
# Java 8, (199+301=) 500 bytes
**M.jar: (the main program)**
```
import javafx.collections.*;class M{static ObservableList o=FXCollections.observableArrayList();static int j,F;int i,f;{F=0;ListChangeListener e=(ListChangeListener.Change c)->{if(f<1)System.out.println((F>0&i>F?--i:i)+"/"+j);};o.addListener(e);o.add(i=++j);}public void f(){F=f=i;j--;o.remove(--i);}}
```
**S.jar: (the server to control the program-flow)**
```
import java.util.*;interface S{static void main(String[]a){List<M>l=new Stack();for(Scanner s=new Scanner(System.in);;){Float n=s.nextFloat();if(n%1==0)l.add(new M());else{int t=(int)(n*10-1);l.get(t).f();l.remove(t);}}}}
```
**Explanation of the code:**
```
import javafx.collections.*;
// Required import for ObservableList, FXCollections, and ListChangeListener
class M{ // Program-class
static ObservableList o=FXCollections.observableArrayList();
// Static list to keep record of all instances
static int j, // Static integer (total number of instances)
F; // Static flag (remove occurred?)
int i, // Non-static integer (id of this instance)
f; // Non-static flag (has been removed)
{ // Non-static initializer-block (shorter than constructor)
F=0; // Reset the static flag remove_occurred, because we add a new instance
o.addListener((ListChangeListener.Change c)->{
// Add a change listener for the ObservableList
// This will monitor any additions or removes on the List
if(f<1) // If this instance is not removed yet:
System.out.println(
// Print:
(F>0&i>F?
// If a removed occurred and this id is larger than the removed instance
--i // Decrease its id by 1 before printing it
: // Else:
i) // Just print its id
+"/"+j);
// Plus the total number of instances left
});
o.add( // Add anything to the Observable list to trigger the listener
i=++j); // Increase the total amount of instances, and set the id of this instance to the last one
} // End of non-static initializer-block
public void f(){// Finalize-method
F=f=i; // Set both flags to the current id
j--; // Decrease the total amount of instances
o.remove(--i);// Remove the current instance from the list to trigger the listener
} // End of Finalize-method
} // End of Program-class
import java.util.*;
// Required import for List, Stack and Scanner
interface S{ // Server-class
static void main(String[]a){
// Mandatory main-method
List<M>l=new Stack();
// List of programs
for(Scanner s=new Scanner(System.in);
// Create a STDIN-listener for user input
;){ // Loop indefinitely
int t=s.nextInt();
// Get the next integer inputted
if(t<1) // If it's 0:
l.add(new M());
// Startup a new program, and add its instance to the list
else{ // Else:
l.get(t).f();
// Close the program with this integer as id
l.remove(t);}
// And remove it from the list of programs
} // End of loop
} // End of main-method
} // End of Server-class
```
**General explanation:**
All programs will keep a record of their own id; the total number of instances left; whether a remove occurred; and which programs have closed.
The server is just a wrapper-class to start and stop programs. When a user inputs `0`, it will startup a new program. When the used inputs a positive integer (i.e. `2`), it will close the program with that id. (Note: S.jar has M.jar as library to access it.)
**Gif to see it in action:**
[](https://i.stack.imgur.com/LBD4h.gif)
***Thoughts to golf it further:***
I just noticed while writing the explanation that I only use the `ObservableList` for it's add/remove-`ListChangeListener`, and don't use its content at all. Removing this and using another type of static Listener might be shorter.
] |
[Question]
[
>
> **TL;DR:** Given an array of chars and a robot in a starting position of the array, write an algorithm than can read a string with movements (`F` for "go forward", `R` for "rotate 90 degrees right" and `L` for "rotate 90 degrees left") and calculate the ending position of the robot. More details in the complete text.
>
>
>
We have at home a very simple programmable device for kids: a small vehicle with buttons to make the vehicle go forward, turn 90 degrees left or turn 90 degrees right. Something similar to this:
[](https://i.stack.imgur.com/n00Wom.jpg)
We also have a foam mat with letters like this:
[](https://i.stack.imgur.com/Y4pp0m.jpg)
The purpose of all this is to teach the kids both the alphabet and the rudiments of programming, all at once.
### The challenge
Suppose we have randomly arranged our foam mat like this:
```
+---+---+---+---+---+---+---+
| E | R | L | B | I | X | N |
+---+---+---+---+---+---+---+
| O | A | Q | Y | C | T | G |
+---+---+---+---+---+---+---+
| F | W | H | P | D | Z | S |
+---+---+---+---+---+---+---+
| K | V | U | M | J |
+---+---+---+---+---+
| |
+---+
```
Suppose also we have modified the vehicle so that when we program a "go forward" command, the vehicle goes forward exactly size of one square in the mat. So, if the vehicle is in the `U` square and goes north, it stops exactly in the `P` square.
The instructions are all given to the vehicle before it starts to move, and those are:
* `F`: The vehicle goes forward into the next square.
* `R`: The vehicle turns 90 degrees right in its place (no further movement).
* `L`: The vehicle turns 90 degrees left in its place (no further movement).
Once the instructions are given, you can press the "GO" button and send the vehicle to a given position as it will follow every instruction in the given order. So, you can tell the kid to insert the needed instructions for the vehicle to go to a given letter.
You must write the shortest program/function that processes a `string` (input parameter) with a set of instructions and calculates the letter the vehicle stops over (output `string`).
Details:
* The vehicle always starts at the blank square at the bottom, and facing north (towards the `U` square).
* The input string will contain only the letters `F`, `R`, `L` and `G` (for the "go" button). You can use lowercase letters for the mat and the instructions, if you prefer so.
* The algorithm must obey every instruction in the string before the first `G` (every instruction after that is ignored as the vehicle has started moving).
* If the vehicle goes out of the mat at any given moment (even if the input string has not been completely processed), the algorithm must return the string `Out of mat`.
* If not, the algorithm must return the letter the vehicle has stopped over. The starting point counts as a char (or an empty string).
### Examples:
```
Input: FFG
Output: P
Input: FRFRFG
Output: Out of mat
Input: RRFFG
Output: Out of mat
Input: FFFRFFLFG
Output: X
Input: FFFRFFLF
Output: <-- Nothing or a whitespace (the robot has not started moving)
Input: FFFRRFFFG
Output: <-- Nothing or a whitespace (the robot has returned to the starting point)
Input: RRRRRLFFFLFFRFRFGFFRRGRFF
Output: L (Everything after the first G is ignored)
```
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so may the shortest program for each language win!
[Answer]
# JavaScript (ES6), ~~194~~ ~~176~~ ~~169~~ 163 bytes
Saved some bytes thanks to @Luke and @Arnauld.
```
s=>(p=35,d=3,t='ERLBIXN1OAQYCTG1FWHPDZS11KVUMJ11111 11',[...s].every(i=>i=='L'?d--:i>'Q'?d++:i<'G'?+t[p+=[1,8,-1,-8][d%4]]||!t[p]?p=1/0:p:0)?'':t[p]||'Out of mat')
```
Ungolfed:
```
s=>(
p=35,
d=3,
t='ERLBIXN1OAQYCTG1FWHPDZS11KVUMJ11111 11',
[...s].every(i=>i=='L'?d--:
i<'Q'?d++:
i<'G'?+t[p+=[1,8,-1,-8][d%4]]||!t[p]?p=1/0:p:
0
)?'':
t[p]||'Out of mat'
)
```
```
f=
s=>(p=35,d=3,t='ERLBIXN1OAQYCTG1FWHPDZS11KVUMJ11111 11',[...s].every(i=>i=='L'?d--:i>'Q'?d++:i<'G'?+t[p+=[1,8,-1,-8][d%4]]||!t[p]?p=1/0:p:0)?'':t[p]||'Out of mat')
console.log(f('FFG')); //P
console.log(f('FRFRFG')); //Out of mat
console.log(f('RRFFG')); //Out of mat
console.log(f('FFFRFFLFG')); //X
console.log(f('FFFRFFLF')); //(space)
console.log(f('FFFRRFFFG')); //(space)
console.log(f('RRRRRLFFFLFFRFRFGFFRRGRFF')); //L
console.log(f('FFFFFRRFG')); //Out of mat
```
[Answer]
# [Python 2](https://docs.python.org/2/), 235 bytes
```
x=0;y=1;a=4;b=3
p='ERLBIXN','OAQYCTG','FWHPDZS','aKVUMJ','aaa '
r=''
for i in input():
if'G'==i:r=p[a][b];break
elif'G'>i:
b+=x;a-=y;
if(-1<a<5)-1or(''<p[a][b:]<'a')-1:r='Out of mat';break
else:x,y=[[y,-x],[-y,x]][i<'R']
print r
```
[Try it online!](https://tio.run/##VZBJb4MwEIXv/hVWLkNUkEqXCzCVupkutGlpuiIfTGoUqykgh6jw6@kQIlW1ffj83psZ2XXXLKvyoF9Unxonk0nf4n7YoR8qPApzPGQ1wmWanF2/3YMLs9PH9/N5TCRerx4uPp6I1O3L893NAEpxYBYBWFFZbrgp6dSbxpkGjJsCYkA0gcU6UzLLZZhbrb4Y16utd2IoxfM9bEPlYRfSxRSO50cqOp56fmUdgGgsDWQECkikZjDbNLwq@Ldq4K/jWget22GWda7XSjfzOreVMjMRpCBZbU3ZcNvTe9nP0qw0n9uNHsbrVi/48Bc9CBEDA5HSHiBNd4IgQST/eIfEuyitRAzOWD54MbljbpuM4Rc "Python 2 – Try It Online")
[Answer]
# [Python 3](https://docs.python.org/3/), ~~226~~ ~~231~~ 241 bytes
Second edit; should work now. Again, plenty of optimization to be done.
```
n=input();s="0ERLBIXN00OAQYCTG00FWHPDZS000KVUMJ000000 00000";d=1;c=40;i=0;w=[-1,-9,1,9]
while n[i]!="G"and c>=0:
if n[i]=="F":c+=w[d]
else:d=[d+[-1,3][d<0],-~d%4][n[i]=="R"]
i+=1
print(["Out of mat",s[c]][c in range(len(s))and s[c]!="0"])
```
[Try it online!](https://tio.run/##LU5La8MwGLvnV3iGQUIc@EJ7abxvsJezR7d22XvGh2CnqyFzQ@MSetlfz5pQHXSQhKRm79cbN@l7h9Y1Ox9GvEUKN8X88u7zCWBx8fx19ZoDiI/b5fX3CwA8vL893sMIMjLlBlOucQrcIvAOZZKyZMZSNlNBt7Z1RZy06gRpTktniD5HyAJiV6OMSAXNdIydNCogVd1WmUFp4qFloqQ5A8WSP3M6VfKYL@ghaGNMg2ZrnQ8lXew82azIb@kpa6VWSmpiHdmW7qcK68qFbRQN04N3@AFURX0vhCiEmIv8Hw "Python 3 – Try It Online")
[Answer]
# [Wolfram Language](http://reference.wolfram.com/language)/Mathematica, 300 Bytes
```
p=Re[(1-7I)#[[1]]]&;d=Drop;t=Throw;s=Switch;s[#,0,"Out of mat",_,StringPart["000 0000KVUMJ0FWHPDZSOAQYCTGERLBIXN",p@#]]&@Catch@Fold[If[MemberQ[d[d[Range[4,35],{2,5}],{7}],p@#],#,t@0]&@(s[#2,"F",#+{#[[2]],0},"R",#{1,-I},"L",#{1,I},_,t[#]]&)[#1,#2]&,{4,I},If[StringFreeQ["G"]@#,{"G"},Characters@#]&@#]&
```
Ungolfed:
```
p = Re[(1 - 7 I) #[[1]]] &;
d = Drop;
t = Throw;
s = Switch;
s[#,
0, "Out of mat",
_, StringPart["000 0000KVUMJ0FWHPDZSOAQYCTGERLBIXN", p@#]] &@
Catch@
Fold[
If[MemberQ[d[d[Range[4, 35], {2, 5}], {7}], p@#], #,
t@0] &@(s[#2, "F", # + {#[[2]], 0}, "R", # {1, -I},
"L", # {1, I}, _, t[#]] &)[#1, #2] &,
{4, I},
If[StringFreeQ["G"]@#, {"G"}, Characters@#] &@#] &
```
] |
[Question]
[
You're sick of other players smugly announcing "BINGO" and walking triumphantly past you to claim their prize. This time it will be different. You bribed the caller to give you the [BINGO](https://en.wikipedia.org/wiki/Bingo_(U.S.)) calls ahead of time, in the order they will be called. Now you just need to create a BINGO board that will win as early as possible for those calls, guaranteeing you a win (or an unlikely tie).
Given a delimited string or list of the calls in order, in typical BINGO format (letters included, e.g. `B9` or `G68`, see the rules for more info), output a matrix or 2D list representing an optimal BINGO board for those calls. Assume input will always be valid.
### BINGO Rules:
* 5x5 board
* A "BINGO" is when your card has 5 numbers in a row from the numbers that have been called so far.
* The center square is free (automatically counted towards a BINGO), and may be represented by whitespace, an empty list, `-1`, or `0`.
* The 5 columns are represented by the letters `B`,`I`,`N`,`G`,`O`, respectively.
* The first column may contain the numbers 1-15, the second 16-30, ..., and the fifth 61-75.
* The letters and numbers taken for input may optionally be delimited (by something that makes sense, like a `,` or space) or taken as a tuple of a character and a number.
* Output requires only numbers in each place in the matrix.
* Squares that will not contribute to your early BINGO must be valid, but do not have to be optimal.
* **This is code-golf, shortest code wins**
### Examples:
I'm using this input format for the examples, because it's shorter. See the section above for acceptable input/output formats.
```
O61 B2 N36 G47 I16 N35 I21 O64 G48 O73 I30 N33 I17 N43 G46 O72 I19 O71 B14 B7 G50 B1 I22 B8 N40 B13 B6 N37 O70 G55 G58 G52 B3 B4 N34 I28 I29 O65 B11 G51 I23 G56 G59 I27 I25 G54 O66 N45 O67 O75 N42 O62 N31 N38 N41 G57 N39 B9 G60 I20 N32 B15 O63 N44 B10 I26 O68 G53 I18 B12 O69 G49 B5 O74 I24
Possible Output (this has a horizontal BINGO in 3rd row. A diagonal is also possible.):
[[11,25,42,53,68],
[ 6,22,32,57,62],
[ 2,16, 0,47,61],
[ 3,17,37,59,75],
[ 9,19,41,46,70]]
N42 N34 O66 N40 B6 O65 O63 N41 B3 G54 N45 I16 O67 N31 I28 B2 B14 G51 N36 N33 I23 B11 I17 I27 N44 I24 O75 N38 G50 G58 B12 O62 I18 B5 O74 G60 I26 B8 I22 N35 B1 B4 G53 O73 G52 O68 B10 O70 I30 G59 N43 N39 B9 G46 G55 O64 O61 I29 G56 G48 G49 I19 G57 N37 O72 I25 N32 B13 B7 B15 O71 I21 I20 O69 G47
Must be a vertical BINGO in 3rd (N) column (because 4 N's came before one of each B,I,G,O):
[[11,25,42,53,63],
[ 2,22,34,57,65],
[ 6,16, 0,47,66],
[ 3,17,41,54,75],
[ 9,19,40,46,70]]
```
[Answer]
# Mathematica, 302 bytes
```
(b=Prepend;i=1;n=15#&@@#-15+Range@5&;g=#~b~{N,0};o={#2,#3,#,##4}&@@#&;While[(l=Length@Union[t=(k=Take)[#&@@@g,i]])<5&&Max[#2&@@@Tally@t]<5,i++];If[l<5,m=#&@@Commonest@t;If[m===#,o[g~k~i/.{m,x_}->x/.{_,_}->Nothing],n@#2]&,o@DeleteDuplicates@b[n@#2,<|#->#2&@@@Reverse@g|>@#]~k~5&]~MapIndexed~{B,I,N,G,O})&
```
Unnamed function taking as its argument a list of ordered pairs, such as `{{N,42},{N,34},{O,66},{N,40},...}` (note that the first element in each ordered pair is not a string but rather a naked symbol), and returning a 2D list of integers, where the sublists represent columns (not rows) of the bingo board.
Output for the first test case:
```
{{1,3,2,4,5},{17,18,16,19,20},{31,32,0,33,34},{46,48,47,49,50},{62,63,61,64,65}}
```
In general, when the earliest possible bingo occurs because of a number called in each of the B/I/G/O rows, then those numbers will be in the center row; each column will otherwise contain the four smallest possible numbers (taking the already used number into account). For example, if the first test case is changed so that the second number called is `B12` rather than `B2`, then the first column of the output board will be `{1,2,12,3,4}`.
Output for the second test case:
```
{{1,2,3,4,5},{16,17,18,19,20},{42,34,0,40,41},{46,47,48,49,50},{61,62,63,64,65}}
```
In general, when the earliest possible bingo occurs because of five numbers called in a single column (or four called in the N column), then the remaining four columns contain their five smallest possible numbers in order.
If the second test case is changed from `{{N,42},{N,34},{O,66},{N,40},...}` to `{{O,72},{O,74},{O,66},{N,40},...}` (only the first two entries changed), then the output is:
```
{{1,2,3,4,5},{16,17,18,19,20},{31,32,33,34,35},{46,47,48,49,50},{74,66,72,65,63}}
```
Somewhat ungolfed version:
```
(b=Prepend;i=1;n=15First[#]-15+Range[5]&;g=b[#,{N,0}];o={#2,#3,#,##4}&@@#&;
While[
(l=Length[Union[t=(k=Take)[Apply[#&,g,{1}],i]]])<5
&&
Max[Apply[#2&,Tally[t],{1}]]<5,
i++];
MapIndexed[
If[l<5,
m=First[Commonest[t]];If[m===#,o[k[g,i]/.{m,x_}->x/.{_,_}->Nothing],n[#2]]&,
k[
o[DeleteDuplicates[b[n[#2],Association[Apply[#->#2&,Reverse[g],{1}]][#]]]]
,5]&
],{B,I,N,G,O}
])&
```
The first line is mostly definitions to shorten the code, although `g` prepends the center square `{N,0}` to the input to simplify the bingo-finding. (The `n` function gives the smallest five legal bingo numbers in the `#`th column, 1-indexed. The `o` function takes a 5-tuple and moves the first element so that it's third.)
The `While` loop in lines 2-6 finds the smallest initial segment of the input that contains a bingo. (The third line tests for one-in-each-column bingos, while the fifth line tests for single-column bingos).
For any function `F`, the operator `MapIndexed[F,{B,I,N,G,O}]` (starting in line 7) produces the 5-tuple `{F{B,1},F{I,2},F{N,3},F{G,4},F{O,5}}` (well, technically it's `{F{B,{1}},...}`); we apply a function `F` that creates a bingo-board column out of its two arguments. That function, however, depends on which type of bingo was found: line 8 is true when we have a single-column bingo, in which case the function (line 9) uses the relevant input numbers in the bingo column and default numbers in the other columns. In the other case, the function (lines 10-12) uses the relevant input numbers in the center of each column and default numbers elsewhere.
[Answer]
# JavaScript (ES6) 372 Bytes
Can probably still be golfed a bit, but I don't see how. Suggestions are much appreciated ;)
```
A=a=>[1,2,3,4,5].map(x=>x+15*a),F=a=>{b=[[],[],[i=0],[],[]],a.replace(/[^0-9 ]/g,"").split` `.some(x=>{b[--x/15|(c=0)].push(++x);return b.some((x,i)=>(d=x.length)>4||d==1&i-2&&++c>3)});for(e=[A(0),A(1),A(2),A(3),A(4)];i<5;a=b[i][0],b[i][0]=b[i][2],b[i++][2]=a)for(j=0;j<5&b[i].length<5;j++)b[i][j]<i*15+5?e[i].splice(e[i].indexOf(b[i][j]),1):b[i][j]=e[i].shift();return b}
```
] |
[Question]
[
## The challenge
Your task is to animate Adve the Adventurer moving through a creepy (i.e. Halloween) maze. Adve is a `•`; he's character fluid, though, so he does not mind being represented by a different character.
To animate Adve, you print out each frame; a frame is the map with his current location in it. Adve moves one space forward every turn and never backtracks. He starts in the first row and ends in the last.
## Input
Any reasonable format like a string with a delimiter or string array. You can assume the input will be a map greater than 3\*3, containing only one possible path. The only characters present will be `#` and .
## Output
The frames.
## Example maze ([ok... labyrinth](https://codegolf.stackexchange.com/q/98061/42854?noredirect=1#comment238339_98061))
Here is a map without Adve in it; the first and last frames are this empty map (this map is 9x15):
```
### #####
## #####
## ######
## #
####### #
# ### #
# # # #
# # ###
# #######
# ####
#### ####
#### ###
##### ###
##### ###
##### ###
```
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so shortest code in bytes wins!
The *exact* output for this can be found [here](http://www.pastebin.com/Y2fHazBr) (37 frames).
## This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so shortest code in bytes wins!
[Answer]
## Perl, 84 bytes
*Thanks [@Ton Hospel](https://codegolf.stackexchange.com/users/51507/ton-hospel) for guiding me to the right direction to golf out around 30 bytes!*
Bytecount includes 82 bytes of code and `-0p` flags.
```
/.*/;say y/A/ /r;s/&(.{@{+}})? /A$1&/s||s/ (.{@{+}})?&/&$1A/s||s/ /&/?redo:y;A&;
```
Note that there are two final spaces, and no final newline (it won't work otherwise).
Takes the maze as input as outputs all the needed frames for Adve to get out of it. Note that Adve is a `&` rather than a `•`, since the latter isn't utf8 (and perl doesn't use utf8 by default). Run it with `-0pE` flags :
```
perl -0pE '/.*/;say y/A/ /r;s/&(.{@{+}})? /A$1&/s||s/ (.{@{+}})?&/&$1A/s||s/ /&/?redo:y;A&; ' <<< "### #####
## #####
## ######
## #
####### #
# ### #
# # # #
# # ###
# #######
# ####
#### ####
#### ###
##### ###
##### ###"
```
---
*Just for the eyes*, I also made this animated version, that is a little bit longer, but will clear the terminal between each print and sleep 0.15 sec, so it will look like Adve is actually moving :
```
perl -0nE 'system(clear);/.*/;say y/A/ /r;select($,,$,,$,,0.15);s/&(.{@{+}})? /A$1&/s||s/ (.{@{+}})?&/&$1A/s||s/ /&/?redo:say"\e[H",y/A&/ /r' <<< "### #####
## #####
## ######
## #
####### #
# ### #
# # # #
# # ###
# #######
# ####
#### ####
#### ###
##### ###
##### ###"
```
[Answer]
# JavaScript (ES6), 137
(1 byte saved thx @ETHproductions)
```
m=>(o=>{for(p=m.search` `-o,r=[m];[d,o/d,-o/d].some(q=>1/m[d=q,q+=p]?p=q:0);r.push(q.join``))(q=[...m])[p]=0})(d=1+m.search`
`)||[...r,m]
```
*Less golfed*
```
m=>{
d = o = 1+m.search`\n`; // offset to next row and starting direction
p = m.search` `-o; // starting position, 1 row above the first
for( r=[m]; // r is the output array, start with empty maze
// try moving in 3 directions (no back)
// if no empty cell found, we have exit the maze
[d,o/d,-o/d].some(q => 1/m[d=q,q+=p]? p=q : 0);
r.push(q.join``) // add current frame
)
q=[...m], q[p] = 0; // build frame, '0' used to mark Adve position
return [...r,m] // add last frame with maze empty again
}
```
**Test**
```
F=
m=>(o=>{for(p=m.search` `-o,r=[m];[d,o/d,-o/d].some(q=>1/m[d=q,q+=p]?p=q:0);r.push(q.join``))(q=[...m])[p]=0})(d=1+m.search`\n`)||[...r,m]
function go() {
var i=I.value,r=F(i),
frame=x=>(x=r.shift())&&(O.textContent=x,setTimeout(frame,100))
frame()
}
go()
```
```
#I { width:10em; height: 19em; font-size:10px}
#O { white-space:pre; font-family: monospace; font-size:10px; vertical-align: top; padding: 4px}
```
```
<table><tr><td>
<textarea id=I>### #####
## #####
## ######
## #
####### #
# ### #
# # # #
# # ###
# #######
# ####
#### ####
#### ###
##### ###
##### ###
##### ###
</textarea><button onclick='go()'>go</button></td><td id=O></td></tr></table>
```
] |
[Question]
[
[](https://i.stack.imgur.com/6Ee3A.jpg)
In music theory, an [interval](https://en.wikipedia.org/wiki/Interval_(music)) is the difference between two pitches. Each pitch is defined by the number of half-steps (The difference between C and C#) or whole steps (The difference between C and D). One whole step is the same as two half-steps. Here is a list of all the default intervals and the number of half-steps they represent:
```
0 Perfect Unison
2 Major Second
4 Major Third
5 Perfect Fourth
7 Perfect Fifth
9 Major Sixth
11 Major Seventh
12 Perfect Octave
```
There are 3 variations on the default intervals, **minor**, **diminished**, and **augmented**.
* A **minor** interval is one half-step lower than a major interval, but not a perfect interval. So you have a minor second (1), a minor third (3), a minor sixth (8), and a minor seventh (10). There is no such thing as a minor fourth, minor fifth, minor unison or minor octave since these are all perfect intervals.
* A **diminished** interval is one half-step lower than a minor *or* perfect interval. There is diminished Second (0), diminished third (2), diminished fourth (4), diminished fifth (6), diminished sixth (7), diminished seventh (9) and diminished octave (11).
* An **augmented** interval is one half-step *higher* than a major or perfect interval. We have Augmented Unison (1), Augmented Second (3), Augmented third (5), Augmented Fourth (6), Augmented fifth, (8), Augmented sixth (10), and Augmented seventh (12).
# The challenge:
You must write a program or function that takes a number of half steps or whole steps and then prints *one of* the valid English descriptions of this interval. It doesn't matter which description you pick, as long as it exactly matches the IO table. You can take this as one string
```
"5w" == 5 whole steps
"3h" == 3 half steps
```
or as a number and a string/char.
```
5, "w" == 5 whole steps
3, "h" == 3 half steps.
```
You can assume that every input will be between 0 and 12 half steps.
# IO table
Here is a full list mapping the number of half-steps to all acceptable outputs.
```
0 Perfect unison, Diminished second
1 Minor second, Augmented unison
2 Major second, Diminished third
3 Minor third, Augmented second
4 Major third, Diminished fourth
5 Perfect fourth, Augmented third
6 Diminished fifth, Augmented fourth
7 Perfect fifth, Diminished sixth
8 Minor sixth, Augmented fifth
9 Major sixth, Diminished seventh
10 Minor seventh, Augmented sixth
11 Major seventh, Diminished octave
12 Perfect octave, Augmented seventh
```
Here is some sample I/O:
```
5w Minor Seventh
5h Augmented Third
12h Perfect Octave
12w UNDEFINED
1w Diminished third
2h Major Second
```
[Answer]
# Ruby, Rev B 138 bytes
```
->n,s{i=12-n-n*(s<=>?h)
[a='Augmented','Major','Minor',d='Diminished',a,'Perfect',d][i%7]+' '+%w{seventh fifth third unison}[i%7/4+i/7*2]}
```
5 bytes saved by not repeating `Augmented/Diminished`. 1 byte saved by use of `?h`.
# Ruby, Rev A 144 bytes
```
->n,s{i=12-n-n*(s<=>'h')
%w{Augmented Major Minor Diminished Augmented Perfect Diminished}[i%7]+' '+%w{seventh fifth third unison}[i%7/4+i/7*2]}
```
The idea is to minimise the number of basic intervals (seventh fifth third and unison only) and take advantage of the fact that sevenths and fifths have an analogous relationship to that between thirds and unisons.
There are four types of seventh/third and 3 types of fifth/unison so the index variable `i` is set to 12 minus the number of half steps, so that the first term of the expression `i%7/4 + i/7*2` will correctly select the type of basic interval.
**ungolfed in test program**
```
f=->n,s{ #n = number of steps. s= step size, w or h
i=12-n-n*(s<=>'h') # i=12-n. If s is later in the alphabet than 'h' subtract again for whole steps
%w{Augmented Major Minor Diminished Augmented Perfect Diminished}[i%7]+
' '+%w{seventh fifth third unison}[i%7/4+i/7*2]
}
-1.upto(12){|j|
puts f[j,'h']
}
0.upto(6){|j|
puts f[j,'w']
}
```
**output**
```
Diminished unison
Perfect unison
Augmented unison
Diminished third
Minor third
Major third
Augmented third
Diminished fifth
Perfect fifth
Augmented fifth
Diminished seventh
Minor seventh
Major seventh
Augmented seventh
Perfect unison
Diminished third
Major third
Diminished fifth
Augmented fifth
Minor seventh
Augmented seventh
```
Undefined behaviour inputs: The function gives the correct answer of `diminished union` for -1 halfsteps, but fails for inputs over 12. For example, it outputs `perfect unison` for 14 half steps, as the algorithm is based on a cycle of 14 rather than 12.
[Answer]
## Python 2, 149 bytes
```
def f(n,c):n*=1+(c>'h');print(n-6)%13%2*"Diminished"or"Augmented",'octave seventh sixth fifth fourth third second unison'.split()[71056674174>>3*n&7]
```
First, whole steps are converted to half steps.
Then, `Diminished` vs `Augmented` is printed. These alternate for adjacent `n` except that `n=5` and `n=6` give the same, which is achieved by first putting them across a boundary modulo an odd number.
Finally, the distance is printed, computed via a three-bit lookup table. This is shorter than doing `int('6746543230210'[n])`.
[Answer]
# Python 2.7, 155 bytes
```
s='second unison third fourth sixth fifth seventh octave Diminished Augmented'.split()
def f(n,c):x=0xDE9CB87561430>>[4,8][c>'h']*n;print s[x%2+8],s[x/2%8]
```
[Answer]
# Retina, 153 bytes
```
\d+
$*
(.*)w|h
$1$1
^1*$
$.0
^[02479]|11
Diminished $0
^\d
Augmented $0
10|7
sixth
11
octave
12|9
seventh
8
fifth
4|6
fourth
5|2
third
1
unison
\d
second
```
Input number is first converted to unary, then doubled if followed by `w`, and any letters are removed, leaving only the unary number. This number is then converted back to decimal. Finally, some search and replace is applied to construct the final output.
Example runs:
```
6w => 111111w => 111111111111 => 12 => Augmented 12 => Augmented seventh
7h => 1111111h => 1111111 => 7 => Diminished 7 => Diminished sixth
3w => 111w => 111111 => 6 => Augmented 6 => Augmented fourth
0h => h => => 0 => Diminished 0 => Diminished second
```
[Try it online!](http://retina.tryitonline.net/#code=XGQrCiQqCiguKil3fGgKJDEkMQpeMSokCiQuMApeWzAyNDc5XXwxMQpEaW1pbmlzaGVkICQwCl5cZApBdWdtZW50ZWQgJDAKMTB8NwpzaXh0aAoxMQpvY3RhdmUKMTJ8OQpzZXZlbnRoCjgKZmlmdGgKNHw2CmZvdXJ0aAo1fDIKdGhpcmQKMQp1bmlzb24KXGQKc2Vjb25k&input=OWg)
[Answer]
# [Vitsy](https://github.com/VTCAKAVSMoACE/Vitsy), 166 bytes
Well, this can definitely be further golfed.
```
WW2M1+*a+mZ
'dehsinimiD'
'roniM'
'rojaM'
'tcefreP'
'detnemguA'
'dnoces '
'htruof '
'htxis '
'evatco '
6m1m
6m2m
6m3m
6m5m
7m1m
7m4m
7m5m
8m1m
8m2m
8m3m
8m5m
9m1m
9m4m
```
This works by defining the minimal amount of items possible, then calling those items through the method syntax.
[Try it Online!](http://vitsy.tryitonline.net/#code=V1cyTTErKmErbVoKJ2RlaHNpbmltaUQnCidyb25pTScKJ3JvamFNJwondGNlZnJlUCcKJ2RldG5lbWd1QScKJ2Rub2NlcyAnCidodHJ1b2YgJwonaHR4aXMgJwonZXZhdGNvICcKNm0xbQo2bTJtCjZtM20KNm01bQo3bTFtCjdtNG0KN201bQo4bTFtCjhtMm0KOG0zbQo4bTVtCjltMW0KOW00bQ&input=NQp3&debug=on)
[Answer]
# Javascript 189 bytes
```
a=>(n='sutsftfxFvxov'[N=parseInt(a)*(a.slice(-1)>'v'?2:1)])&&((N>5?N+1:N)%2?'Augmented ':'Dimished ')+'unison,second,third,fourth,fifth,sixth,seventh,octave'.split`,`['ustfFxvo'.indexOf(n)]
F=
a=>
(n='sutsftfxFvxov' //using the right side of the possible answers
//set n = the letter representing
//unison, first, second ...
//set N to 12 for 12h, but 24 for 12w
[N=parseInt(a)*(a.slice(-1)>'v'?2:1)])
&& //if we were out of range (12w) we'll return undefined
(
(N>5?N+1:N)%2? //get Aug or Dim (right side goes)
//DADADAADADADA
// ^^ makes this a pain
'Augmented ':'Dimished '
)
+
//turn n (which is u for unison, x for sixth, etc
//into it's full name
'unison,second,third,fourth,fifth,sixth,seventh,octave'
.split`,`
['ustfFxvo'.indexOf(a)]
```
[Answer]
## Java, ~~225~~ 224 bytes
There has got to be a better way to pack these strings but I don't have any ideas.
```
(i,s)->{String A="Augmented",M="Major",m="Minor",P="Perfect",D="Diminished",d=" Second",f=" Fourth",a=" Sixth",C=" Octave";String[]o=new String[]{D+d,m+d,M+d,A+d,P+f,A+f,D+a,m+a,M+a,A+a,D+C,P+C};i*=s=='w'?2:1;return o[i-1];}
```
Indented:
```
static BiFunction<Integer, Character, String> interval = (i,s) -> {
String A="Augmented",M="Major",m="Minor",P="Perfect",D="Diminished",
d=" Second",f=" Fourth",a=" Sixth",C=" Octave";
String[] o = new String[] {D+d,m+d,M+d,A+d,P+f,A+f,D+a,m+a,M+a,A+a,D+C,P+C};
i *= s=='w' ? 2 : 1;
return o[i-1];
};
```
] |
[Question]
[
URLs are getting too long. So, you must implement an algorithm to shorten a URL.
## i. The Structure of a URL
A URL has 2 main parts: a **domain** and a **path**. A domain is the part of the URL before the first slash. You may assume that the URL does not include a protocol. The path is everything else.
## ii. The Domain
The domain of a URL will be something like: `xkcd.com` `meta.codegolf.stackexcchhannnge.cooom`. Each part is period-seperated, e.g. in `blag.xkcd.com`, the parts are "blag", "xkcd", and "com". This is what you will do with it:
* If it contains more than two parts, put the last two aside and concatenate the first letter of the rest of the parts.
* Then, concatenate that to the first letter to the second-to-last part.
* Add a period and the second and third letter of the second-to-last part.
* Discard the last part.
## iii. The Path
The path will be like: `/questions/2140/` `/1407/`. As before, "parts" are seperated by slashes. For each part in the path, do:
* Add a slash
* If it is completely made of base-ten digits, interpret it as a number and convert to a base-36 integer.
* Otherwise, add the first letter of the part.
At the end, add a slash.
## iv. Misc.
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so shortest code wins.
* The path can be empty, but the URL will always end with a slash.
* There will not be a protocol (e.g. `http://`, `file:///`)
* There will never be less than two parts in the domain.
* Standard loopholes apply.
## Examples
In: `xkcd.com/72/`
Out: `x.kc/20/`
In: `math.stackexchange.com/a/2231/`
Out: `ms.ta/a/1pz/`
In: `hello.org/somecoolcodeintrepreteriijjkk?code=3g3fzsdg32,g2/`
Out: `h.el/s/`
[Answer]
# JavaScript (ES6), 149 bytes
```
u=>u.split`/`.map((p,i)=>i?/^\d+$/.test(p)?(+p).toString(36):p[0]:(d=p.split`.`).slice(0,-1).map((s,j)=>s[l=j,0]).join``+"."+d[l].slice(1,3)).join`/`
```
## Explanation
I made this independent of [@Neil's solution](https://codegolf.stackexchange.com/a/69849/46855) but it ended up looking *very* similar.
```
u=>
u.split`/`.map((p,i)=> // for each part p at index i
i? // if this is not the first part
/^\d+$/.test(p)? // if p is only digits
(+p).toString(36) // return p as a base-36 number
:p[0] // else return the first letter
:
(d=p.split`.`) // d = domain parts
.slice(0,-1).map((s,j)=> // for each domain part before the last
s[l=j,0] // return the first letter, l = index of last domain part
).join``
+"."+d[l].slice(1,3) // add the 2 letters as the final domain
)
.join`/` // output each new part separated by a slash
```
## Test
```
var solution = u=>u.split`/`.map((p,i)=>i?/^\d+$/.test(p)?(+p).toString(36):p[0]:(d=p.split`.`).slice(0,-1).map((s,j)=>s[l=j,0]).join``+"."+d[l].slice(1,3)).join`/`
```
```
<input type="text" id="input" value="math.stackexchange.com/a/2231/" />
<button onclick="result.textContent=solution(input.value)">Go</button>
<pre id="result"></pre>
```
[Answer]
## Pyth, 93 85 bytes
```
Lsm@+jkUTGdjb36J<zxz\/KP>zhxz\/=cJ\.pss[mhd<J_2hePJ\.<tePJ2\/;=cK\/sm+?-djkUThdysd\/K
```
Hand-compiled to pythonic pseudocode:
```
z = input() # raw, unevaluated
G = "abcdefghijklmnopqrstuvwxyz"
k = ""
T = 10
L def y(b): # define y as base10to36
sm join(map(lambda d:
@+jkUTGd (join(range(T),interleave=k)+G)[d],
# the join(..)+G makes "0...9a...z"
jb36 convert(b,36) # returns a list of digit values in base10
J<zxz\/ J = z[:z.index("\/")] # domain portion
KP>zhxz\/ K = z[1+z.index("\/"):][:-1] # path portion
=cJ\. J = J.split(".") # splits domain into parts
pss[ no_newline_print(join(join[ # 1 join yields a list, the other a string
mhd<J_2 map(lambda d:d[0],J[:-2]),
hePJ J[:-1][-1][1],
\. ".",
<tePJ2 J[:-1][-1][1:][:2],
\/ "\/"
; ])
=cK\/ K = K.split("\/")
sm print(join(map(lambda d:
+?-djkUThdysd\/ "\/"+(d[0] if filterOut(d,join(range(T),interleave=k)) else y(int(d))),
# the filter will turn pure number into empty string, which is False
K K)))
```
Finally, the excruciation ends...
[Answer]
## JavaScript ES6, 157 bytes
```
u=>u.split`/`.map((p,i)=>i?/^\d+$/.test(p)?(+p).toString(36):p[0]:p.split`.`.reverse().map((h,i)=>i--?i?h[0]:h[0]+'.'+h[1]+h[2]:'').reverse().join``).join`/`
```
Edit: Saved 4 bytes thanks to Doᴡɴɢᴏᴀᴛ.
[Answer]
# Python 2, ~~378~~ 365 Bytes
**Update**
Golfed it down by a bit. The ~150 Bytes for the base36-function are annoying, but I can't get rid of it until python has a builtin for that...
```
def b(n):
a=abs(n);r=[];
while a :
r.append('0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'[a%36]);a//=36
if n<0:r.append('-')
return''.join(reversed(r or'0'))
u=raw_input();P=u.split("/")[0].split(".")
print"".join([p[0] for p in P[0:-2]]+[P[-2][0]]+["."]+list(P[-2])[1:3]+["/"]+[b(int(p))+"/"if p.isdigit()else p[0]+"/" for p in u.split(".")[-1].split("/")[1:-1]])
```
**Old version**
```
def b(n):
a=abs(n)
r=[]
while a:
r.append('0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ'[a%36])
a//=36
if n<0:r.append('-')
return''.join(reversed(r or'0'))
u=raw_input()
P=u.split("/")[0].split(".")
s=""
if len(P)>2:
for p in P[:-2]:s+=p[0]
s+=P[-2][0]+"."+P[0][1:3]
P=u.split(".")[-1].split("/")[1:-1]
for p in P:
s+="/"+(b(int(p)) if p.isdigit() else p[0])
print s+"/"
```
Since Python does not have a builtin way to convert ints to a base36-String, I took the implementation from numpy and golfed it down. Rest is pretty straightforward, I will golf it down more after work. Suggestions always appreciated in the meantime!
[Answer]
**Pyhton 2, ~~336~~ 329 bytes**
**update**
fixed and shorter thanks to webwarrior
```
def b(a):
r=''
while a:
r+=chr((range(48,58)+range(65,91))[a%36])
a//=36
return ''.join(reversed(r or '0'))
u=raw_input()
P=u.split('/')[0].split('.')
s=''
if len(P)>2:
for p in P[:-2]: s+=p[0]
s+=P[-2][0]+'.'+P[0][1:3]
P=u.split('.')[-1].split('/')[1:]
for p in P: s+='/'+(b(int(p)) if p.isdigit() else p[0])
print s+'/'
```
**original**
DenkerAffe's version with some mods : correctly handle "foo/bar?baz" scheme, plus, no need for negative case in the base36 conversion function.
```
def b(a):
r=''
while a:
r+=('0123456789ABCDEFGHUKLMNOPQRSTUVWXYZ'[a%36])
a//=36
return ''.join(reversed(r or '0'))
u=raw_input()
P=u.split('/')[0].split('.')
s=''
if len(P)>2:
for p in P[:-2]: s+=p[0]
s+=P[-2][0]+'.'+P[0][1:3]
P=u.split('.')[-1].split('/')[1:]
for p in P: s+='/'+(b(int(p)) if p.isdigit() else p[0])
print s+'/'
```
] |
[Question]
[
One aspect of password strength testing is runs of adjacent letters on the keyboard. In this challenge, a program must be created that returns `true` if a string contains any runs of adjacent letters.
## What counts as a run of adjacent letters?
For this simplified version of a password strength tester, a run of adjacent characters is 3 or more letters which are next to each other in a single direction (left, right, above or below) on a QWERTY keyboard. For the purpose of this challenge the layout of the keyboard looks like this:
```
1234567890
QWERTYUIOP
ASDFGHJKL
ZXCVBNM
```
In the diagram above `Q` is below `1` but not below `2`, so a string that contains `1qa` or `aq1` anywhere inside it would make the program return `true`, but `2qa` would not.
## Input
The password string to check. It will only contain the characters `[0-9a-z]` or `[0-9A-Z]` (your choice).
## Output
The program must return a truthy value if the password contains one or more runs of adjacent keys, or falsey if it contains none.
## Examples
The following inputs should output true:
* `asd`
* `ytrewq`
* `ju7`
* `abc6yhdef`
And these inputs should output false:
* `abc`
* `aaa`
* `qewretry`
* `zse`
* `qwdfbn`
* `pas`
## Rules
* Answers may be complete programs or functions.
* Standard loopholes are disallowed.
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), lowest score (in bytes) wins!
[Answer]
# Pyth - ~~66~~ ~~62~~ 60 bytes
Pretty straightforward approach. Checks if any of substrings len 3 are in any of the rotations of the keyboard. Will be using base encoding for keyboard.
```
.E}Rjb+J+Kc+jkS9"0
qwertyuiop
asdfghjkl
zxcvbnm"b.tKN_MJ.:z3
```
[Test Suite](http://pyth.herokuapp.com/?code=.E%7DRjb%2BJ%2BKc%2BjkS9%220%0Aqwertyuiop%0Aasdfghjkl%0Azxcvbnm%22b.tKN_MJ.%3Az3&input=asd&test_suite=1&test_suite_input=asd%0Aytrewq%0Aju7%0Aabc6yhdef%0Aabc%0Aaaa%0Aqewretry%0Azse%0Aqwdfbn%0Apas&debug=0).
[Answer]
# [Japt](https://github.com/ETHproductions/Japt), 78 bytes
**Japt** is a shortened version of **Ja**vaScri**pt**. [Interpreter](https://codegolf.stackexchange.com/a/62685/42545)
```
V=1oA ¬+`0\nqØÆyuiop\n?dfghjkl \nzxcvbnm`;1+¡Y©(((VbX -VbUgY-1)-5 a -5 %A a)bB
```
Outputs `0` for falsey cases; otherwise, a positive integer. The `?` should be replaced with the unprintable Unicode char U+0086, or if you don't want to go to all that trouble, just `as`.
### How it works
```
V=1oA q +"0\nqwertyuiop\nasdfghjkl \nzxcvbnm";1+Um@Y&&(((VbX -VbUgY-1)-5 a -5 %A a)bB
// Implicit: U = input string
V=1oA q // Set variable V to the digits 1-9, plus
+"..."; // this string.
Um@ // Take U and map each character X and its index Y with this function:
Y&& // If Y is 0, return Y; otherwise,
VbX - // take the index of X in V, subtract
VbUgY-1 // the index of (char at position Y - 1 in U) in V,
-5 a -5 // subtract 5, take the absolute value, subtract 5 again,
%A a // take modulo by 10, then take the absolute value.
// This returns 1 for any pair of characters that is adjacent
// within V, horizontally or vertically.
bB +1 // Take the index of 11 in the result and add one.
// Implicit: output last expression
```
[Answer]
## C#, 227
```
int h(string k){var q="1234567890,QWERTYUIOP,ASDFGHJKL,ZXCVBNM,1QAZ,2WSX,3EDC,4RFV,5TGB,6YHN,7UJM,8IK,9OL,";int i=0,j=0;for(;i<k.Length-2;i++)if((q+String.Concat(Enumerable.Reverse(q))).Contains(k.Substring(i,3)))j=1;return j;}
```
0 is falsey, 1 is truthy.
Concatenated all keys horizontal and vertical, and reversed, and checks if any of 3 chars of input is contained within.
C# is really verbose, gotta dive into other languages :(
[Answer]
# PHP, 173+1 bytes
```
while(~$argn[$i+2])($p=preg_match)($r=_.join(".{10}",str_split(($t=substr($argn,$i++,3))))."|$t"._,$d=_1234567890_qwertyuiop_asdfghjkl__zxcvbnm)||$p($r,strrev($d))?die(1):0;
```
Run as pipe with `-nR` with lowercase input or [try it online](http://sandbox.onlinephpfunctions.com/code/27fe1d84d61b3c3d0e1690da075118d8be89ab2f).
[Answer]
## Clojure, 156 bytes
```
#(some(set(for[R[["1234567890""QWERTYUIOP""ASDFGHJKL.""ZXCVBNM..."]]R[R(apply map list R)]r R p(partition 3 1 r)p((juxt seq reverse)p)]p))(partition 3 1 %))
```
This was a quite interesting task to implement.
] |
[Question]
[
First, some definitions.
A [Hadamard matrix](https://en.wikipedia.org/wiki/Hadamard_matrix) is a square matrix whose entries are either +1 or −1 and whose rows are mutually orthogonal. The [Hadamard conjecture](https://en.wikipedia.org/wiki/Hadamard_matrix#Hadamard_conjecture) proposes that a Hadamard matrix of order 4k exists for every positive integer k.
A [circulant matrix](https://en.wikipedia.org/wiki/Circulant_matrix) is a special kind of matrix where each row vector is rotated one element to the right relative to the preceding row vector. That is the matrix is defined by its first row.
It is [known](http://arxiv.org/pdf/1109.0748.pdf) that, except for 4 by 4 matrices, there are **no circulant Hadamard matrices**.
A matrix with m rows and n >= m columns is **partial circulant**, if it is the first m rows of some circulant matrix.
**The task**
For each even integer n starting at 2, output the size of the largest partial circulant matrix with +-1 entries and n columns that has the property that all its rows are mutually orthogonal.
**Score**
Your score is the highest `n` such that for all `k <= n`, no one else has posted a higher correct answer than you. Clearly if you have all optimum answers then you will get the score for the highest `n` you post. However, even if your answer is not the optimum, you can still get the score if no one else can beat it.
**Languages and libraries**
You can use any available language and libraries you like. Where feasible, it would be good to be able to run your code so please include a full explanation for how to run/compile your code in Linux if at all possible.
**Leading entries**
* **64** by Mitch Schwartz in **Python**
[Answer]
# Python 2
Table up to `n = 64`, verified optimal with brute force up to `n = 32`:
```
4 4 0001
8 4 00010001
12 6 000001010011
16 8 0000010011101011
20 10 00010001011110011010
24 12 000101001000111110110111
28 14 0001011000010011101011111011
32 14 00001101000111011101101011110010
36 18 001000101001000111110011010110111000
40 20 0010101110001101101111110100011100100100
44 18 00010000011100100011110110110101011101101111
48 24 001011011001010111111001110000100110101000000110
52 26 0011010111000100111011011111001010001110100001001000
56 28 00100111111101010110001100001101100000001010100111001011
60 30 000001101101100011100101011101111110010010111100011010100010
64 32 0001100011110101111111010010011011100111000010101000001011011001
```
where `0` represents `-1`. If `n` is not divisible by 4 then `m = 1` is optimal. Generated using this code (or small variations of it) but with more trials for higher `n`:
```
from random import *
seed(10)
trials=10000
def calcm(x,n):
m=1
y=x
while 1:
y=((y&1)<<(n-1))|(y>>1)
if bin(x^y).count('1')!=n/2:
return m
m+=1
def hillclimb(x,n,ns):
bestm=calcm(x,n)
while 1:
cands=[]
for pos in ns:
xx=x^(1<<pos)
m=calcm(xx,n)
if m>bestm:
bestm=m
cands=[xx]
elif cands and m==bestm:
cands+=[xx]
if not cands:
break
x=choice(cands)
return x,bestm
def approx(n):
if n<10: return brute(n)
bestm=1
bestx=0
for trial in xrange(1,trials+1):
if not trial&16383:
print bestm,bin((1<<n)|bestx)[3:]
if not trial&1:
x=randint(0,(1<<(n/2-2))-1)
x=(x<<(n/2)) | (((1<<(n/2))-1)^x)
ns=range(n/2-2)
if not trial&7:
adj=randint(1,5)
x^=((1<<adj)-1)<<randint(0,n/2-adj)
else:
x=randint(0,(1<<(n-2))-1)
ns=range(n-2)
x,m=hillclimb(x,n,ns)
if m>bestm:
bestm=m
bestx=x
return bestm,bestx
def brute(n):
bestm=1
bestx=0
for x in xrange(1<<(n-2)):
m=calcm(x,n)
if m>bestm:
bestm=m
bestx=x
return bestm,bestx
for n in xrange(4,101,4):
m,x=approx(n)
print n,m,bin((1<<n)|x)[3:]
```
The approach is simple randomised search with hill climbing, taking advantage of a pattern noticed for small `n`. The pattern is that for optimal `m`, the second half of the first row often has small edit distance from the (bitwise) negation of the first half. The results for the above code are good for small `n` but start deteriorating not long after brute force becomes unfeasible; I would be happy to see a better approach.
Some observations:
* When `n` is odd, `m = 1` is optimal because an odd number of ones and negative ones can't add up to zero. (Orthogonal means dot product is zero.)
* When `n = 4k + 2`, `m = 1` is optimal because in order for `m >= 2` we need to have exactly `n/2` sign reversals among `{(a1,a2), (a2,a3), ... (a{n-1},an), (an,a1)}`, and an odd number of sign reversals would imply `a1 = -a1`.
* The dot product of two rows `i` and `j` in a circulant matrix is determined by `abs(i-j)`. For example, if `row1 . row2 = 0` then `row4 . row5 = 0`. This is because the pairs of elements for the dot product are the same, just rotated.
* Consequently, for checking mutual orthogonality, we only need to check successive rows against the first row.
* If we represent a row as a binary string with `0` in place of `-1`, we can check orthogonality of two rows by taking bitwise xor and comparing the popcount with `n/2`.
* We can fix the first two elements of the first row arbitrarily, because (1) Negating a matrix does not affect whether the dot products equal zero, and (2) We know that there must be at least two adjacent elements with same sign and two adjacent elements with differing sign, so we can rotate to place the desired pair at the beginning.
* A solution `(n0, m0)` will automatically give solutions `(k * n0, m0)` for arbitrary `k > 1`, by (repeatedly) concatenating the first row to itself. A consequence is that we can easily obtain `m = 4` for any `n` divisible by 4.
It is natural to conjecture that `n/2` is a tight upper bound for `m` when `n > 4`, but I don't know how that would be proven.
] |
[Question]
[
Capacitors are notorious for being manufactured with high tolerances. This is acceptable in many cases, but some times a capacity with tight tolerances is required. A common strategy to get a capacity with the exact value you need is to use two carefully measured capacitors in parallel such that their capacities add up to something in the range you need.
The goal in this challenge is, given a (multi) set of capacities, to pair the capacitors such that the total capacity of each pair is in a given range. You also need to find the best set of pairings, that is, the set of pairings such that as many pairs as possible are found.
## Constraints
1. Input comprises in a format of choice
* an unordered list of capacities representing the (multi) set of *capacitors you have*
* a pair of capacities representing the lower and upper bound of the *target range* (inclusive)
2. all capacities in the input are positive integers smaller than 230, the unit is pF (not that that matters).
3. In addition to the list of capacities in the input, the set of *capacitors you have* also contains an infinite amount of capacitors with a value of 0 pF.
4. Output comprises in a format of choice a list of pairs of capacities such that the sum of each pair is in the *target range* specified. Neither the order of pairs nor the order of capacities within a pair is specified.
5. No capacity in the output may appear more often than it appears in the set of *capacitors you have*. In other words: The pairs you output must not overlap.
6. There shall be no possible output satisfying conditions 4 and 5 that contains more pairs of capacities than the output your program produces.
7. Your program shall terminate in O(*n*!) time where *n* is the length of the list representing the set of *capacitors you have*
8. Loopholes shall not be abused
9. The *target range* shall not be empty
## Scoring
Your score is the length of your solution in octets. If your solution manages to solve this problem in polynomial time O(*n**k*) for some *k*, divide your score by 10. I do not know if this is actually possible.
## Sample input
* range 100 to 100, input array `100 100 100`, valid output:
```
0 100
0 100
0 100
```
* range 100 to 120, input array `20 80 100`, valid output:
```
0 100
20 80
```
the output `20 100` is not valid
* range 90 to 100, input array `50 20 40 90 80 30 60 70 40`, valid output:
```
0 90
20 80
30 70
40 60
40 50
```
* range 90 to 90, input array `20 30 40 40 50 60 70 80 90`, valid output:
```
0 90
20 70
30 60
40 50
```
* range 90 to 110, input array `40 60 50`, valid output:
```
40 60
```
[Answer]
# Python 2, 11.5
A Python golf for once:
```
(a,b),l=input()
l=[0]*len(l)+sorted(l)
while l:
e=l[0]+l[-1]
if a<=e<=b:print l[0],l[-1]
l=l[e<=b:len(l)-(a<=e)]
```
I add one 0 pF capacitor for every regular one, there are never any more needed. Then we sort the capacitors and keep pairing the lowest and highest capacitor. If the sum is within the allowable range we print it, if it is above the range we discard the highest, if it's below discard the lowest.
Example input / output:
```
[[90,100], [20,30,40,40,50,60,70,80,90]]
0 90
20 80
30 70
40 60
40 50
```
[Answer]
# CJam, 5.6
This is a direct re-implementation of the algorithm in [orlp](https://codegolf.stackexchange.com/users/4162/orlp)'s answer. If you upvote my answer, please make sure that you also upvote [this answer](https://codegolf.stackexchange.com/a/54113/32852). I also suggest that the answer with the original algorithm is accepted, because I very much doubt that I would have figured out how to solve this elegantly in O(n\*log(n)).
```
l~_,0a*+${(\)@_2$+4$~2$\>{;;\;\+}{<{;+}{oSop}?}?_,1>}g;;
```
[Try it online](http://cjam.aditsu.net/#code=l~_%2C0a*%2B%24%7B(%5C)%40_2%24%2B4%24~2%24%5C%3E%7B%3B%3B%5C%3B%5C%2B%7D%7B%3C%7B%3B%2B%7D%7BoSop%7D%3F%7D%3F_%2C1%3E%7Dg%3B%3B&input=%5B90%20100%5D%20%5B50%2020%2040%2090%2080%2030%2060%2070%2040%5D)
Sample input:
```
[90 100] [50 20 40 90 80 30 60 70 40]
```
Explanation:
```
l~ Get and interpret input.
_, Get length of resistor list.
0a*+ Append the same number of 0 values.
$ Sort the list.
{ Loop until less than 2 entries in list.
( Pop off first value.
\) Pop off last value.
@_ Pull first value to top, and copy it.
2$ Copy last value to top.
+ Add first and last value.
4$~ Copy specified range to top, and unwrap the two values.
2$ Copy sum to top.
\> Swap and compare for sum to be higher than top of range.
{ It's higher.
;;\; Some stack cleanup.
\+ Put first value back to start of resistor list.
}
{ Not higher, so two cases left: value is in range, or lower.
< Compare if sum is lower than bottom of range.
{ It's lower.
;+ Clean up stack and put last value back to end of resistor list.
}
{ Inside range, time to produce some output.
o Output first value.
So Output space.
p Output second value and newline.
}? Ternary operator for comparison with lower limit.
}? Ternary operator for comparison with upper limit.
_, Get length of remaining resistor list.
1> Check if greater 1.
}g End of while loop for processing resistor list.
;; Clean up stack, output was generated on the fly.
```
] |
[Question]
[
Inspired by this question [earlier today](https://codereview.stackexchange.com/questions/97309/generate-probabilities-around-a-numpad), I'd like to see interesting ways various programming languages can turn a numpad into probabilities. Commonly, tile-based games will allow you to use a numpad to move in any direction based on where your character currently is. When making an AI for these games, `Math.random() * 8` is not sufficient, so I had to get a little creative to make the movement look and feel somewhat natural.
A numpad is defined as such:
```
7 | 8 | 9
- - - - -
4 | x | 6
- - - - -
1 | 2 | 3
```
Please note, 5 is an invalid number, as you cannot move onto yourself.
All examples will use these probabilities: `[50, 40, 30, 20, 10]`
If I wanted to generate probabilities around `8`, it would look like this:
```
40 | 50 | 40
-- | -- | --
30 | xx | 30
-- | -- | --
20 | 10 | 20
```
The output would be `[20, 10, 20, 30, 30, 40, 50, 40]` (with 5 omitted) or `[20, 10, 20, 30, null, 30, 40, 50, 40]` (with 5 present)
If I wanted to generate them around `1`, it would look like this:
```
30 | 20 | 10
-- | -- | --
40 | xx | 20
-- | -- | --
50 | 40 | 30
```
The output would be `[50, 40, 30, 40, 20, 30, 20, 10]` (with 5 omitted) or `[50, 40, 30, 40, null, 20, 30, 20, 10]` (with 5 present)
You may write a full program that takes the input in any usual way (command line, stdin) and prints the output, or you may write a function with a number argument, that prints or returns the output. Your program or function should accept one number - the position to generate around. You should use these probabilities: `[50, 40, 30, 20, 10]` (they do not have to be hardcoded).
Shortest code in bytes wins. Standard loopholes are disallowed. Answers posted in the linked thread are disallowed. Trailing or leading spaces are allowed. You may treat position `4` as absent or empty, depending on your preference. I'm not too picky on output format - print it out as comma-separated strings or as an array.
(This is my first question, go easy on me!)
[Answer]
# CJam, 27 bytes
```
12369874s_$\_r#m<f{#4-z)0S}
```
Try it online in the [CJam interpreter](http://cjam.aditsu.net/#code=12369874s_%24%5C_r%23m%3Cf%7B%234-z)0S%7D&input=8).
### Idea
If we go through the digits around **5** in counterclockwise fashion, we obtain the string `12369874` or any of its rotations (depending on the starting point).
After rotating this string so that the input digit **n** is at the leftmost position, the digits in the rotated string have the following probabilities:
```
50 40 30 20 10 20 30 40
```
If we consider the indexes of these digits, which are
```
0 1 2 3 4 5 6 7
```
subtract **4** from each to yield
```
-4 -3 -2 -1 0 1 2 3
```
and take absolute values to get
```
4 3 2 1 0 1 2 3
```
we only have to add **1** and append a **0** to get the desired probabilities.
### Code
```
12369874s e# Push "12369874".
_$ e# Push a sorted copy, i.e., "12346789".
\ e# Swap it with the unsorted original.
_r# e# Find the index of the input in an unsorted copy.
m< e# Rotate the unsorted original that many units left.
f{ } e# For each character C in "12346789":
e# Push the rotated string.
# e# Find the index of C.
4- e# Subtract 4.
z e# Compute the absolute value.
) e# Add 1.
0S e# Push a 0 and a space.
```
[Answer]
# Prolog, 166 bytes
```
a(A,R):-I:J:K:L:M=50:40:30:20:10,B is abs(5-A),member(B:S,[4:[I,J,K,J,L,K,L,M],3:[J,I,J,K,K,L,M,L],2:[K,J,I,L,J,M,L,K],1:[J,K,L,I,M,J,K,L]]),(A/5>1,reverse(S,R);S=R).
```
This uses the fact that the result for 9 is the reverse of the result for 1, same for 2 and 8, 3 and 7 and 4 and 6. There are recognizable patterns to go from the result of 1 to the results of 2,3 and 4 but I'm pretty sure it would be longer to code this than hardcoding the sequences for 1 to 4, which is what I did.
Example: `a(7,R).` outputs `R = [30, 20, 10, 40, 20, 50, 40, 30]`.
[Answer]
# Python - 115
```
a=[50,40,30,20,10,20,30,40]
b=[0,1,2,7,8,3,6,5,4]
def v(n):
c=8-b[n-1]
return[(a[c:]+a[:c])[e]for e in b if e-8]
```
`a` is an array with the values in order around the numpad (counter-clockwise from 1), and `b` maps numbers on the numpad to positions around it. Based on the number of spaces around the numpad for the input number (determined using `b`), it makes an array with that many elements moved from the front of `a` to the end, then uses `b` again to rearrange the elements to correspond with numpad numbers.
[Answer]
# Pyth - 38 bytes
Uses kinda the same technique as the Python answer except with base compression for the two arrays.
```
J_jC"3ê"T*RTm@.<jC"<àR"[[email protected]](/cdn-cgi/l/email-protection)
```
[Try it here online](http://pyth.herokuapp.com/?code=J_jC%22%1B3%C3%AA%C2%8A%22T*RTm%40.%3CjC%22%03%3C%C3%A0R%22T-8%40JtQd.DJ4&input=8&debug=0).
[Answer]
# Java, 190
```
void g(int n){int i[]={8,0,1,2,7,8,3,6,5,4};String v="54321234",s="";n=i[n];if(n>0)v=v.substring(8-n)+v.substring(0,8-n);for(n=0;n++<9;s=", ")if(n!=5)System.out.print(s+v.charAt(i[n])+"0");}
```
`String v` holds the probabilities (divided by 10) in countrclockwise order with input = 1 being the default 50.
`int[]i` translates the input into an index into v. For example, `v.charAt(i[1])` is `5`. Inputs 0 and 5 are invalid so both i[0] and i[5] have a placeholder value of 8 which is the index for '\0' at the end of v.
I rotate the numbers in v to the right by the value i[n], and then print the probabilities as comma separated strings.
] |
[Question]
[
See [Hole #1](https://codegolf.stackexchange.com/questions/39748/9-holes-of-code-golf-kickoff) if you are confused.
What does every kid do after he/she collects buckets of candy over Halloween?
Sort it by type and size, of course1!
## The Challenge
Given a dumped-out bag of candy of varying shapes and sizes, sort the candy from left to right based on:
* First: The amount of candy (so 5 of one will be more left than 4 of another)
* Second (if there are any ties after the first): If the amount is the same, the candy with more **internal area** (based on number of characters) will rank higher.
If after the second sort there is still a tie, then you may choose either to be first.
## Input
You will be given the candy through stdin; strewn about. See examples below.
## Output
Output the candy ordered in the correct order. Note, candy should *always* be placed in *very* neat columns to appease your OCD fish2. The candy of the same type should be placed directly under one another. See examples below.
## What do you mean by "interior area"?
* The interior area of a piece of candy is measured by the total characters making up the candy as a whole.
* Any whitespace within a "border" is considered part of the area of the candy.
* A border is any connected loop of characters, each character diagonal or next to it's neighbor.
For example,
```
+--------+
| |
| |
| |
| |
+--------+
```
has more area than
```
XXXXXXXX
XXXXXXXX
XXXXXXXX
XXXXXXXX
```
even though is has less characters overall.
## Examples
input:
```
_ \| |/ _
_ lllllll -*------------*- -\ /- lllllll
lllllll lllllllll | /\ /\ / | +|\ooooo/|+ lllllllll
lllllllll llll+llll | / \/ \/ | ||o o|| llll+llll
llll+llll lllllllll -*------------*- ||o o|| lllllllll
lllllllll lllllll /| |\ +|/ooooo\|+ lllllll
lllllll | -/ \- |
| | _ |
| -\ /- | lllllll |
| +|\ooooo/|+ | lllllllll |
| ||o o|| | llll+llll |
| ||o o|| + lllllllll rrr--rrr +
+ +|/ooooo\|+ lllllll rr||rr
-/ \- | | || |
| | || |
| | || |
| | || |
| \| |/ | || |
+ -*------------*- | || |
| /\ /\ / | | || |
-\ /- | / \/ \/ | | || |
+|\ooooo/|+ -*------------*- rr||rr
||o o|| /| |\ rrr--rrr
||o o||
+|/ooooo\|+
-/ \-
```
Would become
```
_ \| |/ -\ /- rrr--rrr
lllllll -*------------*- +|\ooooo/|+ rr||rr
lllllllll | /\ /\ / | ||o o|| | || |
llll+llll | / \/ \/ | ||o o|| | || |
lllllllll -*------------*- +|/ooooo\|+ | || |
lllllll /| |\ -/ \- | || |
| | || |
| \| |/ -\ /- | || |
| -*------------*- +|\ooooo/|+ | || |
| | /\ /\ / | ||o o|| | || |
| | / \/ \/ | ||o o|| rr||rr
+ -*------------*- +|/ooooo\|+ rrr--rrr
/| |\ -/ \-
_
lllllll \| |/ -\ /-
lllllllll -*------------*- +|\ooooo/|+
llll+llll | /\ /\ / | ||o o||
lllllllll | / \/ \/ | ||o o||
lllllll -*------------*- +|/ooooo\|+
| /| |\ -/ \-
|
|
|
|
+
_
lllllll
lllllllll
llll+llll
lllllllll
lllllll
|
|
|
|
|
+
_
lllllll
lllllllll
llll+llll
lllllllll
lllllll
|
|
|
|
|
+
```
A second example:
```
qq \/
qq qq qq +-----+
qq qq qq + |
jjjjjjjj qq qq | |
jjjjjj \/ qq qq | |
jjjj +-----+ <---notice that the left side is not connected qq +-------+
jj jj + | <--> <-->
j j | |
jj <> jj | | <--> qq jjjjjjjj
jj jj +-------+ qq jjjjjj
jjjj qq qq jjjj
qq qq jj jj
j j
+---------------------------------------------------------+ jj <> jj
ooooo +---------------------------------------------------------+ jj jj
o yyyyyy jjjj
o ww - notice diagonal border, allowed
o ww jjjjjjjj
o yyyyyy ooooo ooooo jjjjjj
ooooo o yyyyyy o yyyyyy jjjj
o ww o ww jj jj
o ww o ww j j
o yyyyyy o yyyyyy jj <> jj
ooooo ooooo jj jj
jjjj
```
Solution:
```
qq ooooo jjjjjjjj <--> \/ +---------------------------------------------------------+
qq o yyyyyy jjjjjj +-----+ +---------------------------------------------------------+
o ww jjjj <--> + |
qq o ww jj jj | |
qq o yyyyyy j j <--> | |
ooooo jj <> jj +-------+
qq jj jj
qq ooooo jjjj \/
o yyyyyy +-----+
qq o ww jjjjjjjj + |
qq o ww jjjjjj | |
o yyyyyy jjjj | |
qq ooooo jj jj +-------+
qq j j
ooooo jj <> jj
qq o yyyyyy jj jj
qq o ww jjjj
o ww
qq o yyyyyy jjjjjjjj
qq ooooo jjjjjj
jjjj
qq jj jj
qq j j
jj <> jj
qq jj jj
qq jjjj
```
Note that columns have 1 character of spacing between them, and are aligned horizontally at the top. Also note that each candy is in an exact columns, each candy with 1 character of spacing in between.
## Scoring
This is code-golf, so shortest program (in bytes) wins.
1 What else would you do? Obviously you want to display your awesome might and power in the amount of candy you collected, right?
2 I know what you're thinking! A fish has to look through a *curved* bowl at your candy, so therefore it would be distorted anyway! Well, my fish lived (before it died) in a *rectangular* aquarium.
[Answer]
# Ruby, 928 characters
Whew, this one was fun!
```
w=[];b=' ';u=$<.read.split'
';k=->l,z,t,p{loop{y=!!1;z.each{|c|t.each{|o|v=[c[0]+o[0],c[1]+o[1]]
y=!(z+=[v])if v[0]>=0&&v[1]>=0&&v[0]<l.size&&v[1]<l[0].size&&p[l[v[0]][v[1]]]&&!z.index(v)}}
break if y};z};(y=y;z=k[u,[[u.index{|p|y=p.index /\S/},y]],([-1,0,1].product([-1,0,1])-[0,0]),->x{x!=b}]
n=z.min_by{|c|c[0]}[0];m=z.min_by{|c|c[1]}[1];q=Array.new(z.max_by{|c|c[0]}[0]-n+1){b*(z.max_by{|c|c[1]}[1]-m+1)}
z.each{|c|q[c[0]-n][c[1]-m]=u[c[0]][c[1]];u[c[0]][c[1]]=b};w+=[q])while u*''=~/\S/;o=Hash.new 0;w.each{|c|o[c]+=1}
p=->q{e=k[q,((0...q.size).flat_map{|x|[[x,0],[x,q[0].size-1]]}+(1...q[0].size-1).flat_map{|y|[[0,y],[q.size-1,y]]}).select{|c|q[c[0]][c[1]]==b},[[0,1],[0,-1],[1,0],[-1,0]],->x{x==b}]
(q.size*q[0].size)-e.size};r=o.sort_by{|k,v|v+(p[k]/1e3)}.reverse.map{|k,v|(k+[b*k[0].size])*v}
r.map!{|k|k+([b*k[0].size]*(r.max_by(&:size).size-k.size))};puts ([b]*r.max_by(&:size).size).zip(*r).map{|r|r.join(b)[2..-1]}
```
You can give the input on STDIN, or you can pass an input file as an argument (like `ruby organize.rb candy.txt`) and it will treat the file as STDIN automatically.
All semicolons can be replaced with newlines; I just glued some lines together to reduce vertical space.
Ungolfed (2367 chars):
```
#!/usr/bin/ruby
input = $<.read.split("\n")
candies = []
# utility method
flood = -> arr, coords, offsets, cond {
loop {
changed = false
coords.each{|c|
offsets.each{|o|
nc = [c[0]+o[0], c[1]+o[1]]
if nc[0] >= 0 && nc[1] >= 0 && nc[0] < arr.length && nc[1] < arr[0].length &&
cond[arr[nc[0]][nc[1]]] && !coords.index(nc)
coords.push nc
changed = true
end
}
}
break if !changed
}
coords
}
# while there are non-whitespace characters in the pile
while input.join =~ /\S/
# get coordinates of the first character to flood-fill on
y = nil
x = input.index{|row| y = row.index /\S/ }
# flood-fill on that character
coords = flood[input, [[x, y]], ([-1,0,1].product([-1,0,1]) - [0, 0]), ->x{x != ' '}]
# x = max, n = min
xx = coords.max_by{|c| c[0] }[0]
nx = coords.min_by{|c| c[0] }[0]
xy = coords.max_by{|c| c[1] }[1]
ny = coords.min_by{|c| c[1] }[1]
# create a properly sized thingy for this one candy
candy = Array.new(xx - nx + 1) {
' ' * (xy - ny + 1)
}
# fill the thingy, while also removing it from the pile
coords.each{|c|
candy[c[0] - nx][c[1] - ny] = input[c[0]][c[1]]
input[c[0]][c[1]] = ' '
}
candies.push candy
end
# group by same candies
candytypes = Hash.new 0
candies.each{|c| candytypes[c] += 1 }
area = -> candy {
# we want to eliminate surrounding spaces
# so flood-fill all spaces that touch the edges
surround = (0...candy.length).flat_map{|x| [[x, 0], [x, candy[0].length-1]] } +
(1...candy[0].length-1).flat_map{|y| [[0, y], [candy.length-1, y]] }
surround.select! {|c| candy[c[0]][c[1]] == ' ' }
surround = flood[candy, surround, [[0,1],[0,-1],[1,0],[-1,0]], ->x{x == ' '}]
# now just subtract amount of surrounding spaces from total amount of chars
(candy.length * candy[0].length) - surround.length
}
columns = candytypes.sort_by {|k, v|
# this is a pretty ugly hack
v + (area[k] / 1000.0)
}.reverse.map{|k, v| (k + [' ' * k[0].length]) * v }
columns.map!{|k| k + ([' ' * k[0].length] * (columns.max_by(&:length).length - k.length)) }
puts ([' '] * columns.max_by(&:length).length).zip(*columns).map{|r| r.join(' ')[2..-1] }
```
] |
[Question]
[
You know those wooden toys with little ball bearings where the object is to move around the maze? This is kinda like that. Given a maze and a series of moves, determine where the ball ends up.
The board is held vertically, and the ball moves only by gravity when the board is rotated. Each "move" is a rotation (in radians).
The maze is simply concentric circular walls, with each wall having exactly one opening into the outer corridor, similar to this (assume those walls are circles and not pointed):

As you can see, the ball starts in the middle and is trying to get out. The ball *will* instantly fall through as soon as the correct orientation is achieved, even if it's midway through a rotation. A single rotation may cause the ball to fall through multiple openings. For instance, a rotation `>= n * 2 * pi` is enough to escape any maze.
For the purposes of the game, a ball located within `0.001` radians of the opening is considered a "fit", and will drop through to the next corridor.
**Input:**
Input is in two parts:
* The maze is given by an integer `n` representing how many walls/openings are in the maze. This is followed by `n` lines, with one number on each, representing where the passage to the next corridor is.
* The moves are given as an integer `m` representing how many moves were taken, followed (again on separate lines) by `m` clockwise rotations *of the board* in radians (negative is anticlockwise).
All passage positions are given as `0 rad = up`, with positive radians going clockwise.
For the sample image above, the input may look like this:
```
7 // 7 openings
0
0.785398163
3.14159265
1.74532925
4.71238898
4.01425728
0
3 // 3 moves
-3.92699082
3.14159265
0.81245687
```
**Output:**
Output the corridor number that the ball ends in. Corridors are zero-indexed, starting from the center, so you start in `0`. If you pass through one opening, you're in corridor `1`. If you escape the entire maze, output any integer `>= n`
For the sample input, there are three moves. The first will cause the ball to fall through **two** openings. The second doesn't find an opening, and the third finds **one**. The ball is now in corridor `3`, so expected output is:
```
3
```
Behavior is undefined for invalid input. Valid input is well-formed, with `n >= 1` and `m >= 0`.
Scoring is standard code golf, lowest number of bytes wins. [Standard loopholes](https://codegolf.meta.stackexchange.com/q/1061/14215) are forbidden. Input must not be hard-coded, but can be taken from standard input, arguments, console, etc. Output can be to console, file, whatever, just make it output somewhere visible.
[Answer]
## JavaScript 200
```
function f(i){with(Math)for(m=i.split('\n'),o=m.slice(1,t=+m[0]+1),m=m.slice(t+1),c=PI,p=2*c,r=0,s=1e-3;m.length;c%=p)abs(c-o[r])<s?r++:abs(t=m[0])<s?m.shift(c+=t):(b=t<0?-s:s,c+=p-b,m[0]-=b);return r}
```
**EDIT** : Here is an **animated** example proving that this solver works : <http://jsfiddle.net/F74AP/4/>
[](http://jsfiddle.net/F74AP/4/)
The function must be called passing the input string.
Here is the call of the example given by the OP :
```
f("7\n0\n0.785398163\n3.14159265\n1.74532925\n4.71238898\n4.01425728\n0\n3\n-3.92699082\n3.14159265\n0.81245687");
```
It returns `3` as intended.
[Answer]
## Perl, ~~211~~ 191
With newlines and indentation for readability:
```
$p=atan2 0,-1;
@n=map~~<>,1..<>;
<>;
while(<>){
$_=atan2(sin,cos)for@n;
$y=abs($n[$-]+$_)<$p-.001
?$_
:($_<=>0)*$p-$n[$-];
$_+=$y for@n;
$p-.001<abs$n[$-]&&++$-==@n&&last;
$_-=$y;
.001<abs&&redo
}
print$-
```
Number of moves in the input is discarded, stdin's eof indicates end of moves.
] |
[Question]
[
[Marshall Lochbaum's online BQN REPL](https://mlochbaum.github.io/BQN/try.html) has an interesting(and aesthetically pleasing) method of displaying arrays. Your task is to implement a version with simpler rules.
```
[2,[3],4,[[[6,[5],7]]]]
```
becomes:
```
┌─
· 2 ┌· 4 ┌·
· 3 · ┌·
┘ · ┌─
· 6 ┌· 7
· 5
┘
┘
┘
┘
┘
```
## Rules for drawing
* A singleton array has
```
┌·
·
```
as its top left corner.
* A non-singleton array has
```
┌─
·
```
as its top left corner.
(In the actual BQN, this is used for rank-0, or "unit" arrays)
* All arrays have
```
┘
```
as their bottom right corner.
* Each element at a certain depth will be displayed at the same depth vertically.
For example, 2 and 4 are displayed 1 unit from the top since they are at depth 1.
* Each further level of nesting depth moves 1 unit down in depth.
* Numbers next to each other will be separated by a single space.
## Other details
* You may take a ragged numeric array in any way your language supports.
* The input will only consist of integers and nested arrays containing integers.
* If your language does not support arrays with depth, you may take a string/other equivalent that your language supports.
* If your language's codepage does not contain the characters `┌ · ─ ┘`, you can count them as 1 byte.
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"). Shortest answer in each language wins.
* Since bacon strips are thin, your code must be thin and small as well.
[Answer]
# [Charcoal](https://github.com/somebody1234/Charcoal), 72 bytes
```
FS≡ι(«⊞υⅉP⌈┌´·↘→⊞υⅉ»)«≔⊕⊟υιM¹⁻ιⅉ┘M⁻ⅉ⊟υ↑¿υ⊞υ⌈⟦ι⊟υ⟧»,«↑≔KD⊕ⅈ←ι§≔ι⊖⌕ι┌¦─↘»ι
```
[Try it online!](https://tio.run/##dZG9asMwEMfn@CkOTydQh36DOwVMIdCAaSm0lA7GluOjjmwsKQmUQMcOGTv0Tbr3UfIijmTloxm66e7@97/fnbIybbM6rbquqFvAkWyMftAtyQkyBmpOOisBicF7kKVKQIhhZN@DxKgSDYdnK7sJBmNTaWpsm8ZovfrkEK6/Vr8/YV@rZwKjuJ7Le5qU@pDah8dmy@0k5icNlaKJtGRZK6ZCapFjUjdoGONAe7NTDmOSRiF5m96257Ek3wcOL7IKDnuX6LFxdSrAxrCDGacLmpopvtBO@vqXjns6v4k32JImQrzF1IpMU33M/YT9uDtR6B287xnqkczFwsHH4qC/JZm7nDtm6Frt4@Ofmy6DXBSp/YYI/N7Oftl1eMbxnPELjohXHC8Zv7bXYd3JrNoA "Charcoal – Try It Online") Link is to verbose version of code. Uses lists rather than arrays because they're easier to input. Explanation:
```
FS≡ι
```
Switch over each character of the input as a string.
```
(«
```
For a `(`, ...
```
⊞υⅉ
```
... save the vertical position as the top margin, ...
```
P⌈┌´·↘→
```
... assume a single-element list, ...
```
⊞υⅉ
```
... and save the vertical position again, this time as the bottom margin.
```
»)«
```
For a `)`, ...
```
≔⊕⊟υι
```
... get the bottom margin of this list, plus 1, ...
```
M¹⁻ιⅉ
```
... move to that row, ...
```
┘
```
... close the list, ...
```
M⁻ⅉ⊟υ↑
```
... move to and forget the top margin of this list, ...
```
¿υ⊞υ⌈⟦ι⊟υ⟧
```
... and update the bottom margin of the containing list if necessary.
```
»,«
```
For a `,`, ...
```
↑≔KD⊕ⅈ←ι
```
... grab the text on the previous row, ...
```
§≔ι⊖⌕ι┌¦─
```
... find the `┌` and change the character after it to a `─`, ...
```
↘
```
... and move to the next column on the original row.
```
»ι
```
Otherwise, just output the current character.
Note that the `·` is in Charcoal's code page (so because it needs to be quoted it ends up costing me two bytes!) but the box-drawing characters are not. They would normally cost three bytes in Charcoal so as I use them four times I have subtracted 8 bytes from Charcoal's calculation.
] |
[Question]
[
An [arithmetico-geometric sequence](https://en.wikipedia.org/wiki/Arithmetico-geometric_sequence) is the elementwise product of an arithmetic sequence and a geometric sequence. For example, `1 -4 12 -32` is the product of the arithmetic sequence `1 2 3 4` and the geometric sequence `1 -2 4 -8`. The nth term of an integer arithmetico-geometric sequence can be expressed as
$$a\_n = r^n \cdot (a\_0 + nd)$$
for some real number \$d\$, nonzero real \$r\$, and integer \$a\_0\$. Note that \$r\$ and \$d\$ are not necessarily integers.
For example, the sequence `2 11 36 100 256 624 1472 3392` has \$a\_0 = 2\$, \$r = 2\$, and \$d = 3.5\$.
### Input
An ordered list of \$n \ge 2\$ integers as input in any reasonable format. Since some definitions of geometric sequence allow \$r=0\$ and define \$0^0 = 1\$, whether an input is an arithmetico-geometric sequence will not depend on whether \$r\$ is allowed to be 0. For example, `123 0 0 0 0` will not occur as input.
### Output
Whether it is an arithmetico-geometric sequence. Output a truthy/falsy value, or two different consistent values.
### Test cases
True:
```
1 -4 12 -32
0 0 0
-192 0 432 -1296 2916 -5832 10935 -19683
2 11 36 100 256 624 1472 3392
-4374 729 972 567 270 117 48 19
24601 1337 42
0 -2718
-1 -1 0 4 16
2 4 8 16 32 64
2 3 4 5 6 7
0 2 8 24
```
False:
```
4 8 15 16 23 42
3 1 4 1
24601 42 1337
0 0 0 1
0 0 1 0 0
1 -1 0 4 16
```
[Answer]
# [Perl 6](https://github.com/nxadm/rakudo-pkg), ~~184~~ ~~128~~ 135 bytes
```
{3>$_||->\x,\y,\z{?grep ->\r{min (x,{r&&r*$_+(y/r -x)*($×=r)}...*)Z==$_},x??map (y+*×sqrt(y²-x*z).narrow)/x,1,-1!!y&&z/y/2}(|.[^3])}
```
[Try it online!](https://tio.run/##VVBJbsIwFN1zCleNIjvYSTzEiReBe7S0UapChVSGGlBjAufgHj1COVj6HZAKG@v7TX9YT@2n7hYOhTNUdq0cBdXhwEaThk4cnezb8YedrhEAtl3Mlwg3tLVhaKOgGmKXWMQaEuHgfCotOcZxHJGnsgyqI23G40W9RtgNo/Np82W32P3@sCbak3hZW7v6JklDOWX84cGF4T5xiTjiQ/z8Kl/IsdvUDs1wUBE0W9kB5hQxRREXFKWEokc0bba2vsOZFIQOcAqKXjTAjBvR/5T0PBdGUyQMh5dlhcd4amTmKaML6S0eg0ypPQdOkUGlhW@hciClNH0XpmQOYC4MRcYTmc5BnafeD5UqoDB9otIpJCqfLGXeD/@@e5uvdpt@WCZyXlwHBw34hLrdkPkV@WUNiNC3nOr1PPM4@KRv46Og4Bf5/0X4rfF6pDu0@wM "Perl 6 – Try It Online")
Computes \$r\$ and \$d\$ from the first three elements and checks whether the resulting sequence matches the input. Unfortunately, Rakudo throws an exception when dividing by zero, even when using floating-point numbers, costing ~9 bytes.
Enumerates the sequence using \$a\_n=r \cdot a\_{n-1}+r^n \cdot d\$.
Some improvements are inspired by Arnauld's JavaScript answer.
### Explanation
```
3>$_|| # Return true if there are less than three elements
->\x,\y,\z{ ... }(|.[^3])} # Bind x,y,z to first three elements
# Candidates for r
x # If x != 0
??map (y+*×sqrt(y²-x*z).narrow)/x,1,-1 # then solutions of quadratic equation
!!y&&z/y/2 # else solution of linear equation or 0 if y==0
?grep ->\r{ ... }, # Is there an r for which the following is true?
( , ...*) # Create infinite sequence
x # Start with x
{ } # Compute next term
r&& # 0 if r==0
(y/r -x) # d
r*$_ # r*a(n-1)
($×=r) # r^n
+ * # r*a(n-1)+d*r^n
Z==$_ # Compare with each element of input
min # All elements are equal?
```
[Answer]
# JavaScript (ES7), ~~135~~ 127 bytes
```
a=>!([x,y,z]=a,1/z)|!a.some(n=>n)|[y/x+(d=(y*y-x*z)**.5/x),y/x-d,z/y/2].some(r=>a.every((v,n)=>(v-(x+n*y/r-n*x)*r**n)**2<1e-9))
```
[Try it online!](https://tio.run/##dVFBboMwELz3FznFdtaA18bGUuHYF/QW5YAaUrVKTQUtApS/0w29NKoj32ZnPDO77/VQ9y/d2@eXDO2xWU7lUpfVhu1HmGA@lDWodOaXTZ307UfDQlkFftlP6bhjx5JNYpKjmLkQSZ6OHAiXR5jTKcXDr6ArqzpphqabGBsg8LJig2TjLogp7WQQIxedEIF@wEfVSM/58tKGvj03ybl9Zdvn7rvZ8oe/2IntFUgDCkFqPPB/0wzoRXCpPNLIaBIq9BbQKwsyLwhQmdc5wd4WOiIlggJtiZYB5hYskr9xCFr7WARptDPg0IMnUm4doMvoDwemAOVjDsZmCpTWRImXkuhUEa1Fua@9QNlodAPkaYFaWhMlaKLkYMFFfZHkuApvZtun@txHbrO65VdD1PEqGtQ17N0lGFz3cO@yUeWK37n77X6WHw "JavaScript (Node.js) – Try It Online")
## How?
We use two preliminary tests to get rid of some special cases. For the main case, we try three different possible values of \$r\$ (and the corresponding values of \$d\$, which can be easily deduced) and test whether all terms of the input sequence are matching the guessed ones. Because of potential rounding errors, we actually test whether all squared differences are \$<10^{-9}\$.
### Special case #1: less than 3 terms
If there are less than 3 terms, it's always possible to find a matching sequence. So we force a truthy value.
### Special case #2: only zeros
If all terms are equal to \$0\$, we can use \$a\_0=0\$, \$d=0\$ and any \$r\neq 0\$. So we force a truthy value.
### Main case with \$a\_0=0\$
If \$a\_0=0\$, the sequence can be simplified to:
$$a\_n=r^n\times n\times d$$
Which gives:
$$a\_1=r\times d\\
a\_2=2r^2\times d$$
We know that \$d\$ is not equal to \$0\$ (otherwise, we'd be in the special case #2). So we have \$a\_1\neq 0\$ and:
$$r=\frac{a\_2}{2a\_1}$$
### Main case with \$a\_0\neq 0\$
We have the following relation between \$a\_{n+1}\$ and \$a\_n\$:
$$a\_{n+1}=r.a\_n+r^{n+1}d$$
For \$a\_{n+2}\$, we have:
$$\begin{align}a\_{n+2}&=r.a\_{n+1}+r^{n+2}d\\
&=r(r.a\_n+r^{n+1}d)+r^{n+2}d\\
&=r^2a\_n+2r.r^{n+1}d\\
&=r^2a\_n+2r(a\_{n+1}-r.a\_n)\\
&=-r^2a\_n+2r.a\_{n+1}
\end{align}$$
We notably have:
$$a\_2=-r^2a\_0+2r.a\_1$$
Leading to the following quadratic:
$$r^2a\_0-2r.a\_1+a\_2=0$$
Whose roots are:
$$r\_0=\frac{a\_1+\sqrt{{a\_1}^2-a\_0a\_2}}{a\_0}\\
r\_1=\frac{a\_1-\sqrt{{a\_1}^2-a\_0a\_2}}{a\_0}$$
[Answer]
# [Wolfram Language (Mathematica)](https://www.wolfram.com/wolframscript/), 55 bytes
```
{}!=Solve[i=Range@Tr[1^#];(a+i*d)r^i==#,{r,a,d},Reals]&
```
[Try it online!](https://tio.run/##TY9da4MwFIbv8yvOLJR9RPCcxMR0CN7semP2zloIrXZCa4tKGZT@dnd0uxiBkPPk/eCc/PBVnfzQ7PxYp5vxdn9I8/PxWhVN@unbQ5WtuwK3i/L10b80z/unbtuk6ULeOunl/i4/K3/sy@X4XtfZ7Fut@qvvepHvfFsIgI@uaYcCoM7W57fvS1f1fXNus3xgfsgvx2YoFjKAoAQol5IN/38CIRBCDUgQKhIR8BEhOuKHVgyRnAFyaCCMEwYYORUzdiZRgkcEZRhGQLEBQ5ykLYFSjkSoldVgyYFjFBsLZCN2WNAJoBOkTYSASjGYqkOymHA5p0/tgIYLNLDWADcbzaNiEIMBy3riL9JiVsSTiNQUpAAn81@8prnhdzOm8z1vKQIZbNqgLMcf "Wolfram Language (Mathematica) – Try It Online")
`Solve` return all solution forms. The result is compared with `{}` to check if there is any solution.
] |
[Question]
[
Given an integral polynomial of degree strictly greater than one, completely decompose it into a composition of integral polynomials of degree strictly greater than one.
### Details
* An *integral polynomial* is a polynomial with only integers as coefficients.
* Given two polynomials `p` and `q` the *composition* is defined by `(p∘q)(x):=p(q(x))`.
* The [*decomposition*](https://en.wikipedia.org/wiki/Polynomial_decomposition) of an integral polynomial `p` is a finite ordered sequence of integral polynomials `q1,q2,...,qn` where `deg qi > 1` for all `1 ≤ i ≤ n` and `p(x) = q1(q2(...qn(x)...))`, and all `qi` are not further decomposable. The decomposition is not necessarily unique.
* You can use e.g. lists of coefficients or built in polynomial types as input and output.
* Note that many builtins for this task actually decompose the polynomials over a given *field* and not necessarily integers, while this challenge requires a decomposition integer polynomials. (Some integer polynomials might admit decomposition into integer polynomials as well as decomposition that contain rational polynomials.)
### Examples
```
x^2 + 1
[x^2 + 1] (all polynomials of degree 2 or less are not decomposable)
x^6 - 6x^5 + 15x^4 - 20x^3 + 15x^2 - 6 x - 1
[x^3 - 2, x^2 - 2x + 1]
x^4 - 8x^3 + 18x^2 - 8x + 2
[x^2 + 1, x^2 - 4x + 1]
x^6 + x^2 + 1
[x^3 + x + 1, x^2]
x^6
[x^2, x^3]
x^8 + 4x^6 + 6x^4 + 4x^2 + 4 = (x^2 + 1)^4 + 3
[x^2 + 3, x^2, x^2 + 1]
x^6 + 6x^4 + x^3 + 9x^2 + 3x - 5
[x^2 + x - 5, x^3 + 3*x], [x^2 + 5*x + 1, x^3 + 3*x - 2]
```
Use Maxima for generating examples: [Try it online!](https://tio.run/##y02syMxN/P@/QKNCU8HKVqEizljbSKtC29iaqxAuZKRboW1ozVUEFzBV0AaSJgq6IEltM2uugqLMvBKNgvycypTU5PzcAg0TrUKNIg2QqZqaOkDC@v9/AA "Maxima – Try It Online")
Some decomposition algorithms can be found [here](https://www.sciencedirect.com/science/article/pii/S0747717185800122) and [here](https://www.sciencedirect.com/science/article/pii/S0747717189800276).
[Answer]
# [Pari/GP](http://pari.math.u-bordeaux.fr/), 84 bytes
```
f(p)=[if(q'',[f(q),r],p)|r<-x*divisors(p\x),r''&&p==subst(q=substpol(p,r,x),x,r)][1]
```
Based on the algorithm described [here](https://www.sciencedirect.com/science/article/pii/S0747717185800122 "Polynomial decomposition algorithms").
[Try it online!](https://tio.run/##TY3dCoMwDIVfJXihrbYwf3Ew9yJOwTE2CjJjdaODvbtLrcJucnLyJTnYaSUfuCx3hryq1Z2NQSBqEi50I5B/9Uma8Kbeahr0xPBiCASB72NVTa/rNLPRKQ49Q6EFcSM0b@q4WTrE/sMQ5BlQq@dMrWeNBzaOC6hNm0AEsQDTFiChCE2b20FOTUaD5EBNuk8St0J1vbAL5c7LjZOSTdzHCP4DbCnJZaFjxRrivN3K9qMduNfHDadrct7w5Qc "Pari/GP – Try It Online")
[Answer]
# [Wolfram Language (Mathematica)](https://www.wolfram.com/wolframscript/), 29 bytes
```
Decompose[#/.x->x+a,x]/.a->0&
```
[Try it online!](https://tio.run/##XY47C4MwFIX3/ooLgkuj9jE4FKWDFboV6RYyRHu1gjGShJJS@tvTOJQ@psv5OOfcI7i5ouCmb7hrM1dgI8UkNdIgiW2U2yUnliUxj/JV6BQfLzXXOMnhriGDM68HpKWSoui73mhaeYMUx9Fgh4o@opRA@iSwZQQsm@9uMXfMeR8/2MmLfSmHCw02kMRgIcohWEPo/QQqvKHyU37eMt9xUv1o/vAXnMFbtx/C3As "Wolfram Language (Mathematica) – Try It Online")
I have the example set up here to compose a random polynomial from random quadratics (or less), expand it out, and then try to decompose it.
It's necessary to complicate the polynomial with dummy variable (a) since the built-in will not attempt to decompose a monomial.
I notice that the answer often has much larger coefficients than in the original composition, but they are indeed always integers.
] |
[Question]
[
>
> This question is based on [what I came up with](https://codegolf.stackexchange.com/a/127426/70347) to answer [another question](https://codegolf.stackexchange.com/q/127397/70347).
>
>
>
Sometimes the questions here ask to draw some ASCII art. One simple way to store the data for the art is [RLE (run-length encoding)](https://en.wikipedia.org/wiki/Run-length_encoding). So:
```
qqqwwwwweeerrrrrtttyyyy
```
becomes:
```
3q5w3e5r3t4y
```
Now to draw a big ASCII art you maybe be getting data like this (ignoring the new line characters):
```
19,20 3(4)11@1$20 11@19,15"4:20 4)19,4:20 11@
^^^
Note that this is "20 whitespaces"
(Character count: 45)
```
The characters used for the ASCII art are never going to be lowercase or uppercase letters or numbers, only signs, marks and symbols but always in the printable ASCII character set.
You want to save some space in that string, so you replace the numbers with the uppercase character set (being 'A' equals to 1, 'B' equals to 2 until 'Z' equals to 26), because you are never going to get more than 26 repetitions of a character. So you get:
```
S,T C(D)K@A$T K@S,O"D:T D)S,D:T K@
(Character count: 34)
```
And finally you notice that some groups of (letter+symbol) are repeating, so you substitute the groups that appear 3 times or more in the string by the lowercase character set, in order or appearance in the string, but storing in a buffer the substitutions made (in the format "group+substitution char" for each substitution), and leaving the rest of the string as is. So the following groups:
```
S, (3 times)
T (4 times)
K@ (3 times)
```
gets substituted by 'a', 'b' and 'c', respectively, because there are never going to be more than 26 groups repeating. So finally you get:
```
S,aT bK@c
abC(D)cA$bcaO"D:bD)aD:bc
(Character count: 9+24=33)
```
[The last step only saves 1 byte because the groups that actually save characters after being substituted are the ones appearing 4 times or more.]
### The challenge
Given a string containing the RLE data to draw an ASCII art (with the restrictions proposed), write the shortest program/function/method you can in order to compress it as described. The algorithm must print/return two strings: the first one containing the dictionary used for the compression, and the second one being the resulting compressed string. You may return the strings as a Tuple, an array, List or whatever, in the given order.
Note that if the string cannot be compressed in the step 2, the algorithm must return an empty string as first return value and the result of the step 1 as second return value.
You do not need to include the result of step 1 in the output values, I just include them in the examples for clarification purposes.
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so may the shortest answer for each language win!
### Another test case
```
Input: 15,15/10$15,15/10"10$10"10$10"10$10"15,15/
Output of step 1: O,O/J$O,O/J"J$J"J$J"J$J"O,O/
Final algorithm output: O,aO/bJ$cJ"d
abcabdcdcdcdab
---
Input: 15,15/10$15,15/10"
Output of step 1: O,O/J$O,O/J"
Final algorithm output: <empty string>
O,O/J$O,O/J"
```
[Answer]
## JavaScript (ES6), ~~168~~ 167 bytes
Returns an array of two strings: `[dictionary, compressed_string]`.
```
s=>[(a=(s=s.replace(/\d+/g,n=>C(n|64),C=String.fromCharCode)).match(/../g)).map(v=>s.split(v)[a[v]||3]>=''?D+=v+(a[v]=C(i++)):0,i=97,D='')&&D,a.map(v=>a[v]||v).join``]
```
### Test cases
```
let f =
s=>[(a=(s=s.replace(/\d+/g,n=>C(n|64),C=String.fromCharCode)).match(/../g)).map(v=>s.split(v)[a[v]||3]>=''?D+=v+(a[v]=C(i++)):0,i=97,D='')&&D,a.map(v=>a[v]||v).join``]
console.log(f('19,20 3(4)11@1$20 11@19,15"4:20 4)19,4:20 11@'))
console.log(f('15,15/10$15,15/10"10$10"10$10"10$10"15,15/'))
```
[Answer]
# [Python 2](https://docs.python.org/2/), ~~269~~ ~~280~~ ~~268~~ 266 bytes
Nothing fancy going on here. Good opportunity to use some simple regular expressions.
The first version failed for strings containing special characters that were interpreted within the regex. Second version (using re.escape) works with all the test cases. That correction cost 11 bytes.
Second version did not assign substitution characters in order, as required in the problem specification, and as pointed out by @CarlosAlejo. So, back to the drawing board.
## Corrected version, further golfed
* -6 bytes saved by not printing output on two lines
* +3 bytes: Switching to code substitutions via a string to allow meeting the challenge as specified.
* -4 bytes: Since I'm no longer calling re.findall twice, I don't need to rename it
* -5 bytes: switching from for loops to while loops.
* -2 bytes thanks to @Comrade Sparkle Pony
```
import re
S=re.sub
b=a=input()
for i in re.findall('\d{1,2}',a):
b=S(i, chr(64+int(i)),b)
n,s,p=96,'',0
while p<len(b):
c=b[p:p+2];f=b.count(c)
if f>2and not c in s:n+=1;s+=c+chr(n)
p+=2
p=0
while p<len(s):k=s[p:p+2];v=s[p+2];b=S(re.escape(k),v,b);p+=3
print s,b
```
[Try it online!](https://tio.run/##VU/RSsQwEHzPVywiJCFLufTOg7ZG/Id7VB@aNKXhahqS9kTEb6@J4INPOzvMzsyGz3VafL3v7j0scYVoyUVFW6VNE6165XzYVsbJuERw4HwWVKPzQz/PjL4OXxLrb4o9bwlodWEOwUyRnU/C@ZU5zlFz4jFhUM0ZKcUD@ZjcbCE8ztYzXe6M0i@hDaJ@60alK7Ns@dRwAm6E8anu/QB@WcGU9NR6oWSXhDKiBPksC0LVJKj/zom3V5X@fG8FFlA65g9sMn2w7Mrxlgt22eFIQsyVIaHedyobrA9wZCcu5bO8z7jMBuXD3anNW@Yb/EWZpz8 "Python 2 – Try It Online")
[Answer]
# Lua, 215 bytes
Just a good bit of pattern matching.
I think Lua's underrated when it comes to golfing... look at all those statements squished together!
```
g,c=string.gsub,string.char
u=g(arg[1],"%d%d?",function(n)return c(n+64)end)l,d=97,""g(u,"..",function(m)n,e=0,g(m,".", "%%%0")g(u,e,function()n=n+1 end)if n>2 then
l,s=l+1,c(l)d,u=d..m..s,g(u,e,s)end
end)print(u,d)
```
[Answer]
# [Python 2](https://docs.python.org/2/), 186 bytes
```
from re import*
S=sub('\d+',lambda m:chr(int(m.group(0))+64),input())
Q=[]
for p in findall('[A-Z].',S):
if S.count(p)>2:a=chr(len(Q)+97);Q+=[p+a];S=sub(escape(p),a,S)
print''.join(Q),S
```
I was hoping to finally find use for `re.subn` :C
```
# first step - convert all numbers to uppercase letters
S=sub('\d+',lambda m:chr(int(m.group(0))+64),input())
# empty list to hold encoding of second step
Q=[]
# find every encoded pair (uppercase letter and some char)
for p in findall('[A-Z].',S):
# if it occures 3 or move times
if S.count(p)>2:
# get lowercase letter to substitute with
a=chr(len(Q)+97)
# store encoding into list
Q+=[p+a]
# update string - substitute pair with lowercase letter
S=sub(escape(p),a,S)
# output
# encodings of second step, space, result
# if nothing was compressed at step 2, space would prepend result (of step 1)
print''.join(Q),S
```
[Compressed at step 2](https://tio.run/##JY7LboMwEEX3/opRFcme2EExoa0gImo/AbErYeHwSFzhhxxY9OupaVf3oZmj63/mh7Ppuo7BGQgDaONdmPekLp/LjdFrz6mYlLn1CkzRPQLTdmYmuQe3eHZE5G8ZCm39MjNEUpVNS0YXwIO2MGrbq2litPk8fLUJFTUWBPQIddK5JXI8XtJClRt2GiyrkOfveK542Xiu2vP/huHZKT/EW6EigPgQF1CafDu9fYh6XanMRXqEE8tQyg@5i37TXMjXl6yIKfa5@HOxp78)
[Not compressed at step 2](https://tio.run/##NY7LDoIwFAX3/YrGmLTXVhTiI0Iw8RMIO5FF5SE1tL2psPDrEWPcncWcyeB76JyNpqn1zlDfUG3Q@WFF8vQ13jm71YLJXpl7raiJq85zbQdugod3I/ItgDjsQGqL48ABSJYWJWmdp0i1pa22tep7zorL@loGTOYQE6pbmgeVG2cPwjmKVfrV9o3lGYjTEZJMpAUKVSa/huZVKWxmVqpZQNDPBYwFT6e/D5lPEwv3Mtxvwu3yPxbsAw)
---
# [Python 2](https://docs.python.org/2/), 246 bytes
Whole second step done in repl lambda of re.sub. Just for fun.
```
from re import*
Q=[]
S=sub('\d+',lambda m:chr(int(m.group(0))+64),input())
S=sub('[A-Z].',lambda m:(lambda m:S.count(m)>2and(m in Q or not Q.append(m))and chr(Q.index(m)+97)or m)(m.group(0)),S)
print''.join(Q[i]+chr(i+97)for i in range(len(Q))),S
```
[Try it online!](https://tio.run/##JY7LboMwEEX3/opRFcme2EExoa0gImo/AbErYeHwSFzhhxxY9OupaVf3oZmj63/mh7Ppuo7BGQgDaONdmPekLp/LjdFrz6mYlLn1CkzRPQLTdmYmuQe3eHZE5G8ZCm39MjNEUpVNS0YXwIO2MGrbq2litPk8fLUJFTUWBPQIddK5JXI8XtJClRt2GiyrkOfveK542Xiu2vP/huHZKT/EW6EigPgQF1CafDu9fYh6XanMRXqEE8tQyg@5i37TXMjXl6yIKfa5@HOxp78)
[Answer]
# [Perl 5](https://www.perl.org/) `-pl`, 81 bytes
```
s/\d+/chr$&+64/ge;$b=a;for$a(/([A-Z].)(?=.*\1.*\1)/g){s/\Q$a/$b/g&&($\.=$a.$b++)}
```
[Try it online!](https://tio.run/##K0gtyjH9/79YPyZFWz85o0hFTdvMRD891VolyTbROi2/SCVRQ18j2lE3KlZPU8PeVk8rxhCENfXTNauBugJVEvVVkvTT1dQ0VGL0bFUS9VSStLU1a///NzTVMTTVNzRQgTGUQGw0Eiz1L7@gJDM/r/i/rq@pnoGhwX/dghwA "Perl 5 – Try It Online")
Prints the encoded string on the first line, the triples on the second line
[Answer]
# [Ruby](https://www.ruby-lang.org/) `-p`, 133 bytes
```
gsub(/(\d+)(.)/){(64+$1.to_i).chr+$2}
c=?`;s=''
$_.scan(/(..)(?=.*\1.*\1)/){s+=$&+c.succ!if !s[$&]}
puts s.scan(/(..)(.)/){gsub$1,$2}
```
[Try it online!](https://tio.run/##bU3RDoIwDHznK5AssDkcFMEEDcH/EIMyo/IChMKDMfy6cyMxMcaHtte7Xq8fq4dSNxwrGtDiwhkVLGBPuok5ATG0Zc2EvPecRJMls/y0w8zzLFIKlOdGW4RgNM/EsgBTxoo8Iy6XAkcpF/XVXuCBuMfJ6sYBbfz2zUkmmoCv/ysFqR@F9prGDGAPRGMzUx8SJ97qTfOpPyPNW5BoIYCQfIBj8E@fpT@nr7Yb6rZBtere "Ruby – Try It Online")
] |
[Question]
[
# Introduction
For my 5th KOTH, I present to you a challenge based on the well-known game [Battleship](https://github.com/Thrax37/hit-master) with a few twists. You'll only command one ship, whose type you'll be able to select between the 5 "traditionnal" classes, but you'll be able to undertake multiple actions each turn, including moving! This is played as a FFA (Free For All) and your goal will be to be the last ship standing.
# Principle
The game is turn-based. At the start of the game, you'll have to choose the class of your ship. Then each turn, players will be able to execute several actions depending on their ship.
The game takes place on a 2D grid (X, Y) whose side is defined this way :
`X = 30 + numberOfPlayer`
`Y = 30 + numberOfPlayer`
The starting position of each ship is random.
Play order is randomized each turn, and you won't know your position in the "queue" nor the number of players. The game lasts for **100 turns** or until there's only one ship left alive.
Each time you hit an enemy ship or get hit, you'll earn or lose points. The player with the highest score wins. A bounty will be awarded to the winner (value depending on the number of participants).
The controller provides you with input via command arguments, and your program has to output via stdout.
# Syntax
***First Turn***
Your program will be called **once** without any argument. You'll have to ouput an integer between 1 and 5 (inclusive) to select your ship :
`1` : Destroyer [length: 2, moves/turn: 3, shots/turn: 1, range: 9, mines: 4]
*Skill* : Free ship rotations (no cooldown)
`2` : Submarine [length: 3, moves/turn: 2, shots/turn: 1, range: 5, mines: 4]
*Skill* : Can Plunge/Surface (see outputs). While underwater, you can only use "Movement" actions and can be seen only with a scan. You can't be hit by a shot, but can take damage from mines.
`3` : Cruiser [length: 3, moves/turn: 1, shots/turn: 2, range: 9, mines: 2]
*Skill* : Can Repair (see outputs)
`4` : Battleship [length: 4, moves/turn: 1, shots/turn: 3, range: 7, mines: 1]
*Skill* : Can Shield (see outputs)
`5` : Carrier [length: 5, moves/turn: 1, shots/turn: 1, range: 7, mines: 3]
*Skill* : Shots deal AOE (Area Of Effect) damage to target (1 range splash damage). If the target is hit with the shot, up to 2 cells of **this** ship will also be damaged.
***Turns***
**Input**
Each time your program is called, it will receive arguments in this format:
`Round;YourPlayerId;X,Y,Direction;Hull;Moves,Shots,Mines,Cooldown;Hits,Sunken,Damage;Underwater,Shield,Scan;Map`
Rounds are 1-indexed.
**Example input**
```
1;8;1,12,0;111;1,2,2,0;0,0,0;0,0,0;UUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUXXXX.......UUUUUUUUXXXX.......UUUUUUUUXXXX.......UUUUUUUUXXXX.......UUUUUUUUXXXX.......UUUUUUUUXXXX.O.....UUUUUUUUXXXX.O.....UUUUUUUUXXXX.O.....UUUUUUUUXXXX.......UUUUUUUUXXXX.......UUUUUUUUXXXX.......UUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU
```
Here, it's the 1st round, you're player 8.
Your ship is positioned on (X = 1, Y = 12) and your direction is toward the top (0 = Top, 1 = Right, 2 = Bottom, 3 = Left).
Your hull is not damaged (your ship has a length of 3, and each bit is true [1 = OK, 0 = Damaged]).
You can move 1 time, shoot 2 times, have 2 mines left and your "skill" is available (cooldown = 0).
You didn't hit anything, nor have sunken any ship and you didn't get hit either.
You're not underwater, your shields (if any) are not activated and your scan isn't either.
More on the map later...
**Output**
You have to output a String describing what actions you'll execute this turn. The order of the characters in your output String will define the orders of the actions. You can output the same actions multiple times if it doesn't exceed the limits of your ship. If one or multiple actions is invalid, each one will separately be considered as `W`. Here's the list of available actions :
`M` : Move 1 cell in the direction you're facing (consume 1 move)
`B` : Back 1 cell from the direction you're facing (consume 1 move)
`C` : Rotate your ship clockwise (consume 1 move / free for Destroyers)
`K` : Rotate your ship counterclockwise (consume 1 move / free for Destroyers)
`A` : Ram your ship in the direction you're facing (works only if another ship is occupying the cell in the direction you're facing / doesn't move your ship / consume all moves)
`F` : Fire 1 shot to a cell in range (consume 1 shot). Must be followed by the targetted cell in this format ([+-]X[+-])Y / example : `F+2-3`)
`N` : Place 1 mine to a cell adjacent to your ship (consume all shots and 1 mine). Must be followed by the targetted cell in this format ([+-]X[+-])Y / example : `N+0+1`)
`S` : Activate your scan for the next turn (consume all shots)
`R` : Repair the damaged hull the closest to the "head" of your ship (consume all shots, cooldown = 3 turns / Cruiser only)
`P` : Plunge/Surface (consume all shots, cooldown = 3 turns, max duration = 5 turns / Submarine only)
`D` : Activate your shield preventing the next damage during your next turn (consume all shots, cooldown = 3 / Battleship only)
`W` : Wait (does nothing)
*Clarification*: "Consume all moves/shots" means you can only use this action if you have not used any of your moves/shots before during this turn.
**Example output**
`MF+9-8CM` : Moves 1 cell, then fires on the cell whose relative position to the "head" of your ship is (targetX = X + 9, targetY = Y - 8), turns clockwise and finally moves 1 cell again.
# Gameplay
**The Grid**
Here's an example grid (33 x 13) where 3 players are placed :
```
███████████████████████████████████
█ █
█ 00 █
█ 2 █
█ 2 █
█ 2 █
█ █
█ 11111 █
█ M █
█ █
█ █
█ █
█ █
█ █
███████████████████████████████████
```
As we can see, there's also a Mine `M` right next to the player 1.
Let's take player 2 to understand positioning and direction :
Player 2's position is X = 3, Y = 4, Direction = 3. Since its direction is "Bottom", the rest of his "ship cells" are positioned "over" its "head" (X = 3, Y = 3) & (X = 3, Y = 2)
**Player's map**
The last argument each players receive is their "own" map. By default a ship detects everything in a **range of 5 cells**, but it can activate a **Scan** to increase this range to **9**.
The argument is always 361 (19 x 19) characters long. It represents the square centered around the "head" of your ship, where each character corresponds to an element defined this way :
`.` : Empty cell
`O` : Your ship
`M` : Mines
`X` : Wall (cells out of the map)
`U` : Unknown (will be revealed by a scan)
`A` : Enemy ship undamaged cell
`B` : Enemy ship damaged cell
`C` : Enemy ship underwater undamaged cell (only seen with a scan)
`D` : Enemy ship underwater damaged cell (only seen with a scan)
`W` : Wreckage (dead ship)
The string is composed of 19 characters of the first line, followed by 19 charcters of the second lines ... until the 19th line.
Lets take a look at what player 2 receives with and without a scan (line breaks for better understanding, but not send to players) :
```
XXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXX
XXXXXX.............
XXXXXX.......AA....
XXXXXX...O.........
XXXXXX...O.........
XXXXXX...O.........
XXXXXX.............
XXXXXX.......AAAAA.
XXXXXX........M....
XXXXXX.............
XXXXXX.............
XXXXXX.............
XXXXXX.............
XXXXXX.............
XXXXXXXXXXXXXXXXXXX
UUUUUUUUUUUUUUUUUUU
UUUUUUUUUUUUUUUUUUU
UUUUUUUUUUUUUUUUUUU
UUUUUUUUUUUUUUUUUUU
UUUUXXXXXXXXXXXUUUU
UUUUXX.........UUUU
UUUUXX.......AAUUUU
UUUUXX...O.....UUUU
UUUUXX...O.....UUUU
UUUUXX...O.....UUUU
UUUUXX.........UUUU
UUUUXX.......AAUUUU
UUUUXX........MUUUU
UUUUXX.........UUUU
UUUUXX.........UUUU
UUUUUUUUUUUUUUUUUUU
UUUUUUUUUUUUUUUUUUU
UUUUUUUUUUUUUUUUUUU
```
**Mines**
The mines are triggered when a ship moves to a cell occupied by a mine or when a shot is fired on the mine. Mines can't be triggered with the action "Ram".
Mines deal AOE damage (1 range splash damage) to everyone, even to the person who placed the mine. Mines can trigger "chain" explosions if another mine is in the radius of the explosion.
**Rotations**
The rotations are central symmetries centered on the ship's "head". Rotations will only trigger a mine if it is placed on the "destination position" (you won't trigger mines in an arc.
**Area of effect**
1 range splash damage (for mines and Carrier's shots) is defined by a 3x3 (9 cells) square centered on the initial shot/explosion (x, y). It hits those coordinates : `[x - 1; y - 1],[x - 1; y],[x - 1; y + 1],[x; y - 1],[x; y],[x; y + 1],[x + 1; y - 1],[x + 1; y],[x + 1; y + 1]`
# Scoring
The scoring is defined by this formula :
`Score = Hits + (Sunken x 5) - Damage taken - (Alive ? 0 : 10)`
where :
`hits` : number of hits on enemy ship, either by Ram, Shot or Mine explosion (1 hit by enemy ship cell damaged, including chain explosions)
`sunken` : number of "last hit" on an enemy ship which caused it to sink
`damage` : number of hits received (not decreased by Repair, but prevented by Shield)
`alive` : checks wether your ship is alive at the end (at least 1 hull cell undamaged)
# Controller
You can find the controller on [GitHub](https://github.com/Thrax37/hit-master). It also contains two samplebots, written in Java. To make it run, check out the project and open it in your Java IDE. The entry point in the main method of the class Game. Java 8 required.
To add bots, first you need either the compiled version for Java (.class files) or the sources for interpreted languages. Place them in the root folder of the project. Then, create a new Java class in the players package (you can take example on the already existing bots). This class must implement Player to override the method String getCmd(). The String returned is the shell command to run your bots. You can for example make a Ruby bot work with this command : return "C:\Ruby\bin\ruby.exe MyBot.rb";. Finally, add the bot in the players array at the top of the Game class.
# Rules
* Bots should not be written to beat or support specific other bots.
* Writing to files is allowed. Please write to"yoursubmissionname.txt", the folder will be emptied before a game starts. Other external resources are disallowed.
* Your submission has 1 second to respond.
* Provide commands to compile and run your submissions.
* You can write multiple submissions
# Supported Languages
I'll try and support every language, but it needs to be available online for free. Please provide instructions for installation if you're not using a "mainstream" language.
As of right now, I can run : Java 6-7-8, PHP, Ruby, Perl, Python 2-3, Lua, R, node.js, Haskell, Kotlin, C++ 11.
[Answer]
# RandomBot
This is an example bot. It chooses a ship, an action and a target cell (if needed) randomly.
```
import java.util.Random;
public class RandomBot {
int round;
int playerID;
public static void main(String[] args) {
if (args.length == 0) {
Random random = new Random();
int ship = random.nextInt(5);
String[] ships = { "1", "2", "3", "4", "5" };
System.out.println(ships[ship]);
} else {
new RandomBot().play(args[0].split(";"));
}
}
private void play(String[] args) {
round = Integer.parseInt(args[0]);
playerID = Integer.parseInt(args[1]);
String[] actions = { "M", "B", "C", "K", "F", "S", "N", "A" };
Random random = new Random();
int action = random.nextInt(8);
int rangeX = random.nextInt(5);
int rangeY = random.nextInt(5);
int mineX = random.nextInt(1);
int mineY = random.nextInt(1);
String signX = random.nextInt(1) == 1 ? "+" : "-";
String signY = random.nextInt(1) == 1 ? "+" : "-";
System.out.println(actions[action] + (action == 4 ? signX + rangeX + signY + rangeY : "") + (action == 6 ? signX + mineX + signY + mineY : ""));
}
}
```
# PassiveBot
This is an example bot. It does nothing.
```
public class PassiveBot {
int round;
int playerID;
public static void main(String[] args) {
if (args.length == 0) {
System.out.println("5");
} else {
new PassiveBot().play(args[0].split(";"));
}
}
private void play(String[] args) {
round = Integer.parseInt(args[0]);
playerID = Integer.parseInt(args[1]);
System.out.println("W");
}
}
```
[Answer]
# PeaceMaker, Python 2 (Battleship)
PeaceMaker shoots 3 times on the nearest enemies (spiral distance) and moves back and forth in a line while staying at least 2 cells away from mines.
```
from os import sys
def reversedSpiralOrder(length):
#Initialize our four indexes
top = 0
down = length - 1
left = 0
right = length - 1
result = ""
while 1:
# Print top row
for j in range(left, right + 1):
result += str(top * length + j) + ";"
top += 1
if top > down or left > right:
break
# Print the rightmost column
for i in range(top, down + 1):
result += str(i * length + right) + ";"
right -= 1
if top > down or left > right:
break
# Print the bottom row
for j in range(right, left + 1, -1):
result += str(down * length + j) + ";"
down -= 1
if top > down or left > right:
break
# Print the leftmost column
for i in range(down, top + 1, -1):
result += str(i * length + left) + ";"
left += 1
if top > down or left > right:
break
result = result.split(";")
del result[-1]
return result[::-1]
def canMove(x, y, direction, hull, map):
# M = 1, B = 2
moves = 0
if direction == 0:
y1 = -1
y2 = -2
hx1 = hx2 = x1 = x2 = 0
hy1 = -y1 + hull
hy2 = -y2 + hull
elif direction == 1:
x1 = 1
x2 = 2
hy1 = hy2 = y1 = y2 = 0
hx1 = -x1 - hull
hx2 = -x2 - hull
elif direction == 2:
y1 = 1
y2 = 2
hx1 = hx2 = x1 = x2 = 0
hy1 = -y1 - hull
hy2 = -y2 - hull
elif direction == 3:
x1 = -1
x2 = -2
hy1 = hy2 = y1 = y2 = 0
hx1 = -x1 + hull
hx2 = -x2 + hull
if map[y + y1][x + x1] == "." and map[y + y2][x + x2] != "M":
moves += 1
if map[y + hy1][x + hx1] == "." and map[y + hy2][x + hx2] != "M":
moves += 2
return moves
if len(sys.argv) <= 1:
f = open("PeaceMaker.txt","w")
f.write("")
print "4"
else:
arguments = sys.argv[1].split(";")
sight = 19
round = int(arguments[0])
playerID = int(arguments[1])
x = int(arguments[2].split(",")[0])
y = int(arguments[2].split(",")[1])
direction = int(arguments[2].split(",")[2])
hull = arguments[3]
moves = int(arguments[4].split(",")[0])
shots = int(arguments[4].split(",")[1])
mines = int(arguments[4].split(",")[2])
cooldown = int(arguments[4].split(",")[3])
hits = int(arguments[5].split(",")[0])
kills = int(arguments[5].split(",")[0])
taken = int(arguments[5].split(",")[0])
underwater = int(arguments[6].split(",")[0])
shield = int(arguments[6].split(",")[1])
scan = int(arguments[6].split(",")[2])
map = [[list(arguments[7])[j * sight + i] for i in xrange(sight)] for j in xrange(sight)]
initialShots = shots
priorities = reversedSpiralOrder(sight)
actions = ""
sighted = 0
for priority in priorities:
pX = int(priority) % sight
pY = int(priority) / sight
if map[pY][pX] == "A":
sighted += 1
if shots > 0:
shots -= 1
actions += "F" + ("+" if pX - 9 >= 0 else "") + str(pX - 9) + ("+" if pY - 9 >= 0 else "") + str(pY - 9)
if shots == initialShots and sighted > 0:
actions += "D"
elif shots == initialShots and sighted <= 0:
actions += "S"
else:
actions += ""
f = open("PeaceMaker.txt","r")
fC = f.read(1)
lastDirection = int("1" if fC == "" else fC)
y = 9
x = 9
if lastDirection == 1:
if canMove(x, y, direction, len(hull), map) == 1 or canMove(x, y, direction, len(hull), map) == 3:
actions += "M"
elif canMove(x, y, direction, len(hull), map) == 2:
actions += "B"
lastDirection = 0
elif lastDirection == 0:
if canMove(x, y, direction, len(hull), map) == 2 or canMove(x, y, direction, len(hull), map) == 3:
actions += "B"
elif canMove(x, y, direction, len(hull), map) == 1:
actions += "M"
lastDirection = 1
f = open("PeaceMaker.txt","w")
f.write(str(lastDirection))
print actions
```
] |
[Question]
[
## Introduction
>
> In mathematics, a polygonal number is a number represented as dots or pebbles arranged in the shape of a regular polygon. The dots are thought of as alphas (units). These are one type of 2-dimensional figurate numbers.
>
>
> The number 10, for example, can be arranged as a triangle:
>
>
>
> ```
> *
> **
> ***
> ****
>
> ```
>
> But 10 cannot be arranged as a square. The number 9, on the other hand, can be:
>
>
>
> ```
> ***
> ***
> ***
>
> ```
>
> Some numbers, like 36, can be arranged both as a square and as a triangle:
>
>
>
> ```
> ****** *
> ****** **
> ****** ***
> ****** ****
> ****** *****
> ****** ******
>
> ```
>
> By convention, 1 is the first polygonal number for any number of sides. The rule for enlarging the polygon to the next size is to extend two adjacent arms by one point and to then add the required extra sides between those points. In the following diagrams, each extra layer is shown as in red.
>
>
> Triangular Numbers:
>
>
> [](https://i.stack.imgur.com/ppI5p.gif)
>
>
> Square Numbers:
>
>
> [](https://i.stack.imgur.com/qhd5R.gif)
>
>
> Polygons with higher numbers of sides, such as pentagons and hexagons, can also be constructed according to this rule, although the dots will no longer form a perfectly regular lattice like above.
>
>
> Pentagonal Numbers:
>
>
> [](https://i.stack.imgur.com/tSqsz.gif)
>
>
> Hexagonal Numbers:
>
>
> [](https://i.stack.imgur.com/8071C.gif)
>
>
>
Source: [Wikipedia](https://en.wikipedia.org/wiki/Polygonal_number)
## Your task
Given a positive integer *N* (1 <= *N* <= 1000), print every type of Polygonal Number *N* is starting from Triangular Numbers up to and including Icosagonal (20-gon) Numbers.
For example, the number 10 is a triangular number and a decagonal number, so the output should be something like (you can choose your own output format, but it should look somewhat like this):
```
3 10
```
## Test cases
```
1 -> 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
2 -> (None)
3 -> 3
6 -> 3 6
36 -> 3 4 13
```
For reference, the `n`-th `k`-gonal number is:
[](https://i.stack.imgur.com/YQY5C.png)
Credit: xnor
Remember, this is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so the code with the fewest bytes wins.
[Answer]
## Python 3, 68 bytes
```
lambda R:[s+2for s in range(1,19)if(s-2+(4+s*(s-4+8*R))**.5)/2%s==0]
```
For each potential number of sides `s+2`, solves the quadratic formula `R=s*n*(n-1)/2 + n` for `n` to see if the result is a whole number.
Compare (73 bytes):
```
lambda R:[s+2for s in range(1,19)if R in[n+s*n*~-n/2for n in range(R+1)]]
```
An alternative approach of solving for `s` gives 62 bytes in Python 3, but fails on `R=1`.
```
lambda R:{(R-n)*2/n/~-n+2for n in range(2,R+1)}&{*range(3,21)}
```
[Answer]
## JavaScript (ES6), 90 bytes
```
n=>[...Array(21).keys(n--)].slice(3).filter(i=>(Math.sqrt(i*i+8*i*n-16*n)+i-4)%(i+i-4)==0)
```
Solves the quadratic equation. 73 bytes on new enough versions of Firefox:
```
n=>[for(i of Array(18).keys())if(((~-i**2+8*n*-~i)**.5+~-i)/2%-~i==0)i+3]
```
[Answer]
# ><>, 62 + 3 = 65 bytes
```
&1v
v0<;?)+8a:+1~~<
1.292:{<>+n}ao^
>:&:&=?^:&:&)?^:@:@$-{:}++
```
Expects the input at the top of the stack, so +3 bytes for the `-v` flag.
This is my first time programming in ><>, so I may be missing some obvious tricks to shorten the code.
## Explanation:
### Initialization
```
&1v
v0<
1
```
Moves *N* to the register, pushes the counter to the stack (starting at `1`, which corresponds to triangular numbers), and starts the sequence with the values `0` and `1`.
### Main Loop
```
:&:&=?^:&:&)?^:@:@$-{:}++
```
Compares the top of the stack with the register. If it is equal, go to the print routine. If it is greater, go to the reset routine. Otherwise take the difference between the top two stack items, add the counter, and add to the previous top stack item. This calculates the next polygonal number.
### Print
```
.292:{<>+n}ao^
^
```
Prints the counter + 2, followed by a newline, then moves to the reset routine.
### Reset
```
v0<;?)+8a:+1~~<
1 ^
```
Removes the top two stack items and increments the counter. Ends the program if the counter is greater than 18, otherwise pushes the starting numbers `0` and `1` to the stack and returns to the main loop.
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), 22 bytes
```
18pȷµḢ×’×H+µ€_³¬FT:ȷ+3
```
[Try it online!](https://tio.run/nexus/jelly#ASoA1f//MThwyLfCteG4osOX4oCZw5dIK8K14oKsX8KzwqxGVDrItysz////MzY "Jelly – TIO Nexus")
**Explanation**
```
18pȷµḢ×’×H+µ€_³¬FT:ȷ+3
18pȷ - All possible (k-2,n) pairs
µ µ€ - to each pair compute the corresponding polygonal number:
Ḣ - retrieve k-2
×’ - multiply by n-1
×H - multiply by half of n
+ - add n
_³ - subtract the input. There will now be 0's at (k-2,n) pairs which produce the input
¬FT - retrieve all indices of 0's. The indices are now (k-2)*1000+n
:ȷ - floor division by 1000, returning k-3
+3 - add 3 to get all possible k.
```
[Answer]
# Axiom 203 bytes
```
l(x)==(local q,m,a;v:List INT:=[];for i in 3..20 repeat(q:=solve((i-2)*n*(n-1)+2*n-2*x=0,n);if #q>1 then(m:=rhs q.1;a:=rhs q.2;if(m>0 and denom(m)=1)or(a>0 and denom(a)=1)then v:=cons(i,v)));v:=sort v;v)
```
here is less golfed and routine that show numbers
```
l(x)==
local q,m,a
v:List INT:=[]
for i in 3..20 repeat
q:=solve((i-2)*n*(n-1)+2*n-2*x=0,n) -- this would find only rational solutions as r/s with r,s INT
if #q>1 then -- if exist rational solution and denominator =1=> add to list of result
m:=rhs q.1;a:=rhs q.2;
if(m>0 and denom(m)=1)or(a>0 and denom(a)=1)then v:=cons(i,v)
v:=sort v
v
(2) -> [[i,l(i)] for i in 1..45]
Compiling function l with type PositiveInteger -> List Integer
(2)
[[1,[3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20]], [2,[]], [3,[3]],
[4,[4]], [5,[5]], [6,[3,6]], [7,[7]], [8,[8]], [9,[4,9]], [10,[3,10]],
[11,[11]], [12,[5,12]], [13,[13]], [14,[14]], [15,[3,6,15]], [16,[4,16]],
[17,[17]], [18,[7,18]], [19,[19]], [20,[20]], [21,[3,8]], [22,[5]],
[23,[]], [24,[9]], [25,[4]], [26,[]], [27,[10]], [28,[3,6]], [29,[]],
[30,[11]], [31,[]], [32,[]], [33,[12]], [34,[7]], [35,[5]], [36,[3,4,13]],
[37,[]], [38,[]], [39,[14]], [40,[8]], [41,[]], [42,[15]], [43,[]],
[44,[]], [45,[3,6,16]]]
Type: List List Any
```
[Answer]
# [AWK](https://www.gnu.org/software/gawk/manual/gawk.html), 67 bytes
```
{for(k=2;++k<21;)for(n=0;++n<=$1;)if((k/2-1)*(n*n-n)+n==$1)print k}
```
[Try it online!](https://tio.run/nexus/awk#@1@dll@kkW1rZK2tnW1jZGitCeLn2RoA@Xk2tipAgcw0DY1sfSNdQ00tjTytPN08Te08W6CMZkFRZl6JQnbt///GZlwA "AWK – TIO Nexus")
I tried actually solving the quadratic, but checking each value to see if it works is shorter *(and less error-prone for me)*
[Answer]
# R, ~~68~~ 66 bytes
```
N=scan();m=expand.grid(k=1:18,1:N);n=m$V;m$k[m$k*n*(n-1)/2+n==N]+2
```
Reads `N` from stdin. Computes the first `N` k-gonal numbers and gets the `k` where they equal `N`, using xnor's formula; however, saves bytes on parentheses by using `1:18` instead of `3:20` and adding `2` at the end.
`expand.grid` by default names the columns `Var1`, `Var2`, ..., if a name is not given. `$` indexes by partial matching, so `m$V` corresponds to `m$Var2,` the second column.
old version:
```
N=scan();m=expand.grid(k=3:20,1:N);n=m$V;m$k[(m$k-2)*n*(n-1)/2+n==N]
```
[Try it online!](https://tio.run/nexus/r#@@9nW5ycmKehaZ1rm1pRkJiXopdelJmikW1raGVooWNo5adpnWebqxJmnauSHQ3EWnlaGnm6hpr6Rtp5trZ@sdpG/43N/gMA)
[Answer]
# [Pari/GP](http://pari.math.u-bordeaux.fr/), 34 bytes
Pari/GP has a built-in to test whether a number is a polygonal number.
```
x->[s|s<-[3..20],ispolygonal(x,s)]
```
[Try it online!](https://tio.run/nexus/pari-gp#DcqxCoAgEADQXzmcPDhFay1/RBxaDEFO8RoK@nfrzS/DDvM2Icorm4mrtYtLVKS3@pyNj6pvEkwzt6H5v57AO@cI@ih8aSZQYAIogqwZEecH "Pari/GP – TIO Nexus")
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), 20 [bytes](https://github.com/DennisMitchell/jelly/wiki/Code-page)
I just started writing an effective dupe of this challenge (albeit covering all k>1 not just [1,20]) ...so instead I'll answer it!
```
Ṫð’××H+⁸
18pÇċ¥Ðf⁸+2
```
A full program printing a Jelly list representation of the results\*
**[Try it online!](https://tio.run/##y0rNyan8///hzlWHNzxqmHl4@uHpHtqPGndwGVoUHG4/0n1o6eEJaUC@ttH///@NzQA "Jelly – Try It Online")**
\* No results prints nothing;
a single result prints just that number;
multiple results prints a `[]` enclosed, `,` separated list of the numbers
### How?
```
Ṫð’××H+⁸ - Link 1, ith (x+2)-gonal number: list [x,i] e.g. [3,4] (for 4th Pentagonal)
Ṫ - tail & modify (i.e. yield i & make input [x]) 4
ð - new dyadic chain, i.e. left = i, right = [x]
’ - decrement i 3
× - multiply by [x] [9]
H - halve [x] [2]
× - multiply [18]
⁸ - chain's left argument, i 4
+ - add [22]
18pÇċ¥Ðf⁸+2 - Main link: number, n e.g. 36
18p - Cartesian product of range [1,18] with n [[1,1],[1,2],...,[1,36],[2,1],...,[18,1],[18,2],[18,36]]
- (all pairs of [(k-2),i] which could result in the ith k-gonal number being n)
Ðf - filter keep if this is truthy:
⁸ - chain's left argument, n 36
¥ - last two links as a dyad:
Ç - call the last link as a monad (note this removes the tail of each)
ċ - count (this is 1 if the result is [n] and 0 otherwise)
- filter keep result: [[1],[2],[11]]
+2 - add two [[3],[4],[13]]
- implicit print ...due to Jelly representation: [3, 4, 13]
```
] |
[Question]
[
Your task is to regulate traffic on a crossroads. There are 4 roads coming from north, east, south and west.
The input is a string representing the upcoming traffic on each road. For example, `NNNWS` indicates there is a total of 5 cars: three at the north, one at the west and one at the south. The order of characters has no importance here, `NNNWS` is equivalent to `WNNSN`.
You must output the order in which the cars should go, using the priority to the right rule: cars coming from the south must let cars coming from east go first, east gives way to north, north gives way to west and west gives way to south.
For example, with the input `NNNWS`, the south car should go first, then the west car, then the 3 north cars. The output should thus be `SWNNN`.
There are some indecidable cases, for example `NS` or `NNWSE` : you should then output the string `stuck`.
**Test cases**
```
N => N
NW => WN
NWS => SWN
SNW => SWN
SSSSS => SSSSS
ENNNNES => NNNNEES
NS => stuck
NNWSE => stuck
```
[Answer]
# Perl, 65 bytes
Includes +2 for `-lp`
Give input on STDIN. Assumes the empty string is not a valid input
```
#!/usr/bin/perl -lp
s%.%'+(y/NESW/ESWN/*s/N(.*)W/W$1N/,/N/^/S/)'x4%gere+0or$_=stuck
```
If you don't mind the absence of a newline after `stuck` you can drop the `l` option
[Answer]
# PHP, 267 Bytes
use the new [spaceship operator](http://php.net/manual/en/language.operators.comparison.php) and [usort](http://php.net/manual/en/function.usort.php)
-5 Bytes by @IsmaelMiguel
```
<?foreach($f=[E,S,W,N]as$l)$s.=+!($r=strstr)($i=$argv[1],$l);if(in_array($s,[0101,1010,0000]))die(stuck);$x=($p=strpos)($s,"1");$t=$r($j=join($f),$f[$x]).$r($j,$f[$x],1);$a=str_split($i);usort($a,function($x,$y)use($t,$p){return$p($t,$x)<=>$p($t,$y);});echo join($a);
```
## Breakdown
```
# Extended Version without notices
$s="";
foreach($f=["E","S","W","N"] as $l){$s.=+!strstr($i=$argv[1],$l);} #bool concat swap the false true values in string
if(in_array($s,["0101","1010","0000"])){die("stuck");} # NS WE NESW -> stuck = end program
$x=strpos($s,"1"); # find the first false value for an begin for the sort algorithm
$t=strstr($j=join($f),$f[$x]).strstr($j,$f[$x],1); # create the sort pattern
#sort algorithm example sort string = NESW-> N is not in the string
function c($x,$y){
global $t;
return strpos($t,$x)<=>strpos($t,$y); # e.g. comparison E<=>W =-1 , W<=>S=1, W<=>W =0
}
$a=str_split($i); # Input in an array
usort($a,"c"); #sort array
echo join($a);# output array as string
```
[Answer]
## Batch, 216 bytes
```
@echo off
set/pt=
set/an=2,e=4,s=8,w=16,r=0
:l
set/ar^|=%t:~0,1%
set t=%t:~1%
if not "%t%"=="" goto l
set/a"o=449778192>>r&3,l=1053417876>>r&3"
if %l%==0 (echo stuck)else set t=NESWNE&call echo %%t:~%o%,%l%%%
```
Simple port of my JavaScript answer. Takes input on STDIN in upper or lower case.
[Answer]
## JavaScript (ES6), ~~108~~ ~~107~~ ~~106~~ 104 bytes
```
s=>(r=t=`NESWNE`,s.replace(/./g,c=>r|=2<<t.search(c)),t.substr(449778192>>r&3,1053417876>>r&3)||`stuck`)
```
Accumulates a bitmask of which directions have approaching cars and extracts the appropriate portion of the priority string.
] |
[Question]
[
# Characters
Let’s call these Unicode characters **English IPA consonants**:
```
bdfhjklmnprstvwzðŋɡʃʒθ
```
And let’s call these Unicode characters **English IPA vowels**:
```
aeiouæɑɔəɛɜɪʊʌː
```
(Yes, `ː` is just the long vowel mark, but treat it as a vowel for the purpose of this challenge.)
Finally, these are **primary and secondary stress marks**:
```
ˈˌ
```
>
> Note that `ɡ` ([U+0261](http://graphemica.com/%C9%A1)) is not a lowercase g, and the primary stress marker `ˈ` ([U+02C8](http://graphemica.com/%CB%88)) is not an apostrophe, and `ː` ([U+02D0](http://graphemica.com/%CB%90)) is not a colon.
>
>
>
# Your task
Given a word, stack the vowels on top of the consonants they follow, and place the stress markers beneath the consonants they precede. (As the question title hints, such a writing system, where consonant-vowel sequences are packed together as a unit, is called an [abugida](https://en.wikipedia.org/wiki/Abugida).) Given the input `ˈbætəlʃɪp`, produce the output:
```
æə ɪ
btlʃp
ˈ
```
>
> A **word** is guaranteed to be a string of consonants, vowels, and stress marks, as defined above. There will never be consecutive stress marks, and they will always be placed at the start of the word *and/or* before a consonant.
>
>
>
# Test cases
There may be consecutive vowels. For example, `kənˌɡrætjʊˈleɪʃən` becomes
```
ɪ
ə æ ʊeə
knɡrtjlʃn
ˌ ˈ
```
If a word starts with a vowel, print it on the “baseline” with the consonants: `əˈpiːl` becomes
```
ː
i
əpl
ˈ
```
A test case with an initial, stressed vowel: `ˈælbəˌtrɔs` becomes
```
ə ɔ
ælbtrs
ˈ ˌ
```
A long word: `ˌsuːpərˌkaləˌfrædʒəˌlɪstɪˌkɛkspiːæləˈdoʊʃəs` becomes
```
æ
ː ː ʊ
uə aə æ əɪ ɪɛ iəoə
sprklfrdʒlstkkspldʃs
ˌ ˌ ˌ ˌ ˌ ˈ
```
A nonsense example with an initial diphthong, lots of vowel stacking, and no stress markers: `eɪbaeioubaabaaa` becomes
```
u
o
i a
eaa
ɪaaa
ebbb
```
# Reference implementation
Your program should produce the same output as this Python script:
```
consonants = 'bdfhjklmnprstvwzðŋɡʃʒθ'
vowels = 'aeiouæɑɔəɛɜɪʊʌː'
stress_marks = 'ˈˌ'
def abugidafy(word):
tiles = dict()
x = y = 0
is_first = True
for c in word:
if c in stress_marks:
tiles[x + 1, 1] = c
elif c in consonants or is_first:
y = 0
x += 1
tiles[x, y] = c
is_first = False
elif c in vowels:
y -= 1
tiles[x, y] = c
is_first = False
else:
raise ValueError('Not an IPA character: ' + c)
xs = [x for (x, y) in tiles.keys()]
ys = [y for (x, y) in tiles.keys()]
xmin, xmax = min(xs), max(xs)
ymin, ymax = min(ys), max(ys)
lines = []
for y in range(ymin, ymax + 1):
line = [tiles.get((x, y), ' ') for x in range(xmin, xmax + 1)]
lines.append(''.join(line))
return '\n'.join(lines)
print(abugidafy(input()))
```
[Try it on Ideone.](https://ideone.com/pi1GdB)
# Rules
* You may write a function or a full program.
* If your program has a Unicode character/string type, you can assume inputs and outputs use those. If not, or you read/write from STDIN, use the UTF-8 encoding.
* You may produce a string containing newlines, or a list of strings representing rows, or an array of Unicode characters.
* Each row of output may contain any amount of trailing spaces. If you produce a string, it may have a single trailing newline.
* Your program should produce the correct output for arbitrarily long words with arbitrarily long vowel chains, but may assume that the input word is always valid.
* If there are no stress markers, your output may optionally include a final empty row (containing nothing, or spaces).
* The shortest answer (in bytes) wins.
[Answer]
# NARS2000 APL, 138 bytes
```
⍉⌽⊃E,⍨¨↓∘' '¨∨/¨∊∘M¨E←(1+(W∊M←'ˌˈ')++\W∊'bdfhjklmnprstvwzðŋɡʃʒθ')⊂W←⍞
```
[Answer]
# Python, 222 bytes
(202 characters)
```
import re
def f(s):y=[w[0]in'ˈˌ'and w or' '+w for w in re.split('([ˈˌ]?[bdfhjklmnprstvwzðŋɡʃʒθ]?[aeiouæɑɔəɛɜɪʊʌː]*)',s)[1::2]];return[[x[i-1:i]or' 'for x in y]for i in range(max(len(w)for w in y),0,-1)]
```
Returns an array of unicode characters with an array for each row (containing single spaces for each space required)
Not sure where one can get decent output online yet (and I haven't even got the tools to test it properly here either).
I have loaded a version to [**ideone**](http://ideone.com/O2rr7v) that just uses English consonants and vowels with `,` and `.` as stress marks, where I have fudged the test cases to conform.
[Answer]
## JavaScript (ES6), 181 bytes
```
f=
s=>(a=s.match(/[ˈˌ]?.[aeiouæɑɔəɛɜɪʊʌː]*/g).map(s=>/[ˈˌ]/.test(s)?s:` `+s)).map(s=>(l=s.length)>m&&(t=s,m=l),m=0)&&[...t].map(_=>a.map(s=>s[m]||` `,--m).join``).join`
`
;
```
```
<input oninput=o.textContent=f(this.value)><pre id=o>
```
[Answer]
# [Go](https://go.dev), 609 bytes
```
import."strings"
type P struct{x,y int}
func M(s[]int)(m,n int){for _,e:=range s{if e<=m{m=e};if e>=n{n=e}};return}
func f(s string)(L string){T,x,y,F,R:=make(map[P]rune),0,0,1>0,ContainsRune
for _,r:=range s{if R("ˈˌ",r){T[P{x+1,1}]=r}else if R("bdfhjklmnprstvwzðŋɡʃʒθ",r)||F{y=0;x++;T[P{x,y}],F=r,1<0}else if R("aeiouæɑɔəɛɜɪʊʌː",r){y--;T[P{x,y}],F=r,1<0}}
var u,v[]int
for k:=range T{u,v=append(u,k.x),append(v,k.y)}
for y,Y:=M(v);y<Y+1;y++{o:=[]string{}
for x,X:=M(u);x<X+1;x++{if r,ok:=T[P{x,y}];ok{o=append(o,string(r))}else{o=append(o," ")}}
L+=TrimPrefix(Join(o,"")," ")+"\n"}
return}
```
[Attempt This Online!](https://ato.pxeger.com/run?1=bVQ9b-M2GAa6mb-C0CTBjBFvhR3dUiBDcQcYQYY7uEZD2VSqSKIEknKt6jRlCVIN7iGLkQ65As3gqUOHdjY6UAL6A_pr-lJS2sshtAXp_Xqe90u6_-UyefgzpcuQXjIc04CjIE4TobDlx8r6NVP-0Zf_fEE75ciSSgT8UlpI5SnDMwxytlTFhuQ44KpEfsaX-I0t5wsQHTsm3Oidwk8E_pawiSsoByJZBD5mJ25cxC4rp0Z45fKCg1BOBVOZ4D2Wb0vckTr266en4pwAIzklZxM3piGzY5rOZwuRceaQY_iNXx2TrxKuoB55BlrU8Ytn_Ge21dw0lUUEAM5nxWY4JuNy4YqSRZLhzsNb-d9dhVHMUyHV-vsfDr_99aP-WF_XH_7-w0S-f39a5O7xdDMcTlsQkpcLcuoKMj45_hSIsiDJDo_6J32nd_pe_6z39W1dNduWPz86eiG8RGsqcEbWbTvbIsKnEs4L0Ls0TRlf2RkJRxuH9NIapNwpW_-cvJu4b-y1M81P3g3H03w4LJKJO190rSw6rw15a7wyZ7o5eQteUI3pkCAJ8P2X1zQJi-SJMiEdgi0cp63zU5OFLQeyfz10z0UQzwTzg439dRJwY7Oc1j60vuFWifppP23a7-1iKSZVv1u4QIOA4KSfPSpRtxhmV23HWJdUMoknLp4vTFxRwFi9w6PSu6i-1vvUIvgCGr_Deo88BboUNTcXJUGDQWGFesebSn8UEHBV3zY3EYPBXIPWMg6DC9weCAUAfHjE9S3TOxRyCFFXAMYRxk0FLv9j6l1zkwbNNjLMuNkiHEB0GqHOB5sED4-RB36VEvpOtn7YZHiHkbEoISHHDriPqGTWbFO9E00V0siE-pDzqv5gHiO9l0rvwaTvQ2m4AcWksUpgyaCanuLZgWLgoGb7XA1yfQv6DPKhcIEbLOweWqDvMQ70LgElkqkII18AfyRVCJzRqr6GpKs26a4hVd8ZbErpyoDmeu2b4FEKf9qmlSGcQI8wRZhRivQeDIh5ntc2tESD7u3FSzPkbvu7mcPwB2yTMtgSsCxHCch0qTIaGdm3l6PAARV8yUYzWB4V8ZdUHcLn2s_lDvcFrxL1y_vw0N3_BQ)
A direct port of the reference implementation.
## Ungolfed Explanation
```
// map of x-y coords to a character
type tile map[P]rune
func (t tile) Xs() (o []int) {
for k := range t {
o = append(o, k.x)
}
return
}
func (t tile) Ys() (o []int) {
for k := range t {
o = append(o, k.y)
}
return
}
// coordinate pair
type P struct{ x, y int }
func min[T int](s []T) T {
var m T
for _, e := range s {
if e <= m {
m = e
}
}
return m
}
func max[T int](s []T) T {
var m T
for _, e := range s {
if e >= m {
m = e
}
}
return m
}
func f(s string) string {
C, V, S := "bdfhjklmnprstvwzðŋɡʃʒθ", "aeiouæɑɔəɛɜɪʊʌː", "ˈˌ" // constant strs
tiles := make(tile) // the actual map
x, y := 0, 0 // (x0,y0) is the leftmost center
isFirst := true // is this character the first of a line?
for _, r := range s { // for each char...
if strings.ContainsRune(S, r) { // if it's stress...
tiles[P{x + 1, 1}] = r // put it underneath the next syllable
} else if strings.ContainsRune(C, r) || isFirst { // if it's a consonant or the first letter...
y = 0
x++
tiles[P{x, y}] = r // place on the baseline
isFirst = false
} else if strings.ContainsRune(V, r) { // if's a vowel...
y--
tiles[P{x, y}] = r // place 1 above the baseline at the current x
isFirst = false
}
}
// get the ranges for outputting into a string
xs, ys := tiles.Xs(), tiles.Ys()
xmin, xmax := min(xs), max(xs)
ymin, ymax := min(ys), max(ys)
lines := []string{}
for y := ymin; y < ymax+1; y++ { // for each vowel at height y...
line := func() (o []string) {
for x := xmin; x < xmax+1; x++ { // for each syllable on that vowel height...
if r, ok := tiles[P{x, y}]; ok { // get the char
o = append(o, string(r))
} else {
o = append(o, " ") // use a space if there is no vowel there
}
}
return
}()
lines = append(lines, strings.TrimPrefix(strings.Join(line, ""), " ")) // add to the output
}
return strings.Join(lines, "\n") // return the string
}
```
[Attempt This Online!](https://ato.pxeger.com/run?1=pVa9b9tGFAc6VfdXPHApCdOyvRVN3A4BOrSL0RhBC9doTtRRZkTxiLujQ0XR5MVwNbhBFsEdkgL1oKlDh-5GB4pA9_bP6F_Q9-5IWXaT5qOCLd3He-_3e193d_HTQL7488ucR0M-EDDiScZYMsqlMuCzjhePjIc_2qgkG2iP4XggU54NulINtsotUeZbkcxwHzUNCgQ_Fybe_PivD__e2kJzOcgYys0xRFKqvgYjgUN0xBWPjFDMjHMBJkkJOT_YO1RFJhiLiywC39iNAL7WfgC-hINDRAhgwjqxVDCET3ZBIRHUp7WOhF3geS6yvi9DGHbLgHWmrKOEKVTGpreMfvN-Rse3jDJ00nqWZNwIyHnS-LQHGJIiMhMoQxgDgsC0cWyUZAf7tHLoa8TfD2CfsI65ghHsOyLfhSCuuWjLJYlx7e4uCtGsM0JqAgfTNUYwah0d8fL9QT59M4hDidG4K42g-SW1eyE8COE-mfZ6_fjo0TAdZbnS5vjxk6tffv--erk8WT774zcvBI-LRBZXl9UP1fNqXl1UP1aL5dlyVp_TZn1azzywIcYK4xhDBNGsQynUZH7Eh8J3CX3rD5ozRwKw_gqeUtmxjk0RmtsOYfvtDV3b88vtcLwdQKKt6VTEZiS1gUhkVOSdRH-eoPsEgUUh3tm-tYtfq76xMLG1ie3FIU0y8dkqqepGUt8Bh_QFj44sULfbdfXQ9H73nswMNrn-CnvUv48wwX8ZJ9oxJOYjWyFCa2fP5e5gb1LCBuyEsDM9xBJTb-aWFwatQZH1hcoEN0c2BpkosSjGacp7qa1TEKkW8DrW9yzrp0-hzchkDaGly225yYzqTa6HOhUGY9_4MUba2zQoNzZu-IW19FY-tX6lPBIgM4vT41pQLslgS3EXYo4-vdm5B69NiXXOenYsH4u09WBz8_8T3wHek8fiBnvgxs6jQinsAChf4w6dKayDpgbCKdia1bYMZWEw44ZOFDzE6NJwPmOzaiRqu98y79L1EDZjOtVRAk_YEEo8Au0ZkWR-qVEE5zRgnbHdH6_tj9t9HCAlcsIiHBw61MnUNZc9JUj9Dg7vWhMbOzje2LgV9_VmsjGnmByJZHBkYOzibyOF5uggbe-i9iy1Zy8ZsAxLC1giYNkAlivAdaC2D1w1IaBDdrBN0qmhVQhyuArgKvV3aHUCa_mgY8Aq3boHHU1fBYHdbepy8ipRD7zgZlwKFMVs5lQ9SAZxlKATLpMNX7viDLP2q7lwcUYJbhK0wrHTcNUV-yoZ7SkRJ6XfLn0hMcskhoy8wNEKiA3v9-lNQt66klu_6P6ljSDet5lnNRsZ0mxKc9o8fT741T1rhDbNK4Bik2DUV5LtUwCb17fpjrB3mpIjvckEL7_e1aWp5unypFrkeB0-xGtyDtWC9Qyu5aw-fTgNMRgTb1jNs3pWvVSo8Gh5Vp-mAq_RE1z1SKDz0AUfVdEAXF3C8kxUczbMUMU8QmMZA6hnKHJts5rXp3lSn6eEDPU5gwS185Q5GSCCV5dpD-VmRlXPtZUDYvgcGO3QVV2fOsONxkwX9XlezVU9G_KUVGPk3F8-o2FaLbSpFrhVXQw1YaMVotGX-CRAbxqIGx90Bj-sPr-5jPPlGa4XyIfjP4rh82KBIaguAJJqLnGR6VwN01ghfqrNEDHT_vIESc8saReQWRMZIFecGxjcnn239DjHP25pFQwkxgg4w2bkrFrgBhO9Xs8GdLq6nKPry9nlnNoGX9Eisu-DqCtx3jxO6HTwo25CJY8P8e4eFo9Js1ctOQu3V2_Pnd1XSE3b4n3xwv3-Aw)
] |
[Question]
[
Tonight, my fiancée took me out to dinner to celebrate my birthday. While we were out, I heard *Happy Birthday* sung to 5 different guests (including myself), in a restaurant full of 50 people. This got me wondering - the original birthday problem (finding the probability that 2 people in a room of `N` people share the same birthday) is very simple and straightforward. But what about calculating the probability that at least `k` people out of `N` people share the same birthday?
In case you're wondering, the probability of at least 5 people out of 50 total people sharing the same birthday is about 1/10000.
## The Challenge
Given two integers `N` and `k`, where `N >= k > 0`, output the probability that at least `k` people in a group of `N` people share the same birthday. To keep things simple, assume that there are always 365 possible birthdays, and that all days are equally likely.
For `k = 2`, this boils down to the original birthday problem, and the probability is `1 - P(365, N)/(365)**N` (where `P(n,k)` is [the number of k-length permutations formed from n elements](https://en.wikipedia.org/wiki/Permutation#k-permutations_of_n)). For larger values of `k`, [this Wolfram MathWorld article](http://mathworld.wolfram.com/BirthdayProblem.html) may prove useful.
## Rules
* Output must be deterministic, and as accurate as possible for your chosen language. This means no Monte Carlo estimation or Poisson approximation.
* `N` and `k` will be no larger than the largest representable integer in your chosen language. If your chosen language has no hard maximum on integers (aside from memory constraints), then `N` and `k` may be arbitrarily large.
* Accuracy errors stemming from floating-point inaccuracies may be ignored - your solution should assume perfectly-accurate, infinite-precision floats.
## Test Cases
Format: `k, N -> exact fraction (float approximation)`
```
2, 4 -> 795341/48627125 (0.016355912466550306)
2, 10 -> 2689423743942044098153/22996713557917153515625 (0.11694817771107766)
2, 23 -> 38093904702297390785243708291056390518886454060947061/75091883268515350125426207425223147563269805908203125 (0.5072972343239854)
3, 3 -> 1/133225 (7.5060987051979735e-06)
3, 15 -> 99202120236895898424238531990273/29796146005797507000413918212890625 (0.0033293607910766013)
3, 23 -> 4770369978858741874704938828021312421544898229270601/375459416342576750627131037126115737816349029541015625 (0.01270542106874784)
3, 88 -> 121972658600365952270507870814168157581992420315979376776734831989281511796047744560525362056937843069780281314799508374037334481686749665057776557164805212647907376598926392555810192414444095707428833039241/238663638085694198987526661236008945231785263891283516149752738222327030518604865144748956653519802030443538582564040039437134064787503711547079611163210009542953054552383296282869196147657930850982666015625 (0.5110651106247305)
4, 5 -> 1821/17748900625 (1.0259790386313012e-07)
4, 25 -> 2485259613640935164402771922618780423376797142403469821/10004116148447957520459906484225353834116619892120361328125 (0.0002484237064787077)
5, 50 -> 786993779912104445948839077141385547220875807924661029087862889286553262259306606691973696493529913926889614561937/7306010813549515310358093277059651246342214174497508156711617142094873581852472030624097938198246993124485015869140625 (0.00010771867165219201)
10, 11 -> 801/8393800448639761033203125 (9.542757239717371e-23)
10, 20 -> 7563066516919731020375145315161/4825745614492126958810682272575693836212158203125 (1.5672327389589693e-18)
10, 100 -> 122483733913713880468912433840827432571103991156207938550769934255186675421169322116627610793923974214844245486313555179552213623490113886544747626665059355613885669915058701717890707367972476863138223808168550175885417452745887418265215709/1018100624231385241853189999481940942382873878399046008966742039665259133127558338726075853312698838815389196105495212915667272376736512436519973194623721779480597820765897548554160854805712082157001360774761962446621765820964355953037738800048828125 (1.2030611807765361e-10)
10, 200 -> 46037609834855282194444796809612644889409465037669687935667461523743071657580101605348193810323944369492022110911489191609021322290505098856358912879677731966113966723477854912238177976801306968267513131490721538703324306724303400725590188016199359187262098021797557231190080930654308244474302621083905460764730976861073112110503993354926967673128790398832479866320227003479651999296010679699346931041199162583292649095888379961533947862695990956213767291953359129132526574405705744727693754517/378333041587022747413582050553902956219347236460887942751654696440740074897712544982385679244606727641966213694207954095750881417642309033313110718881314425431789802709136766451022222829015561216923212248085160525409958950556460005591372098706995468877542448525403291516015085653857006548005361106043070914396018461580475651719152455730181412523297836008507156692430467118523245584181582255037664477857149762078637248959905010608686740872875726844702607085395469621591502118462813086807727813720703125 (1.21685406174776e-07)
```
[Answer]
# [MATL](https://github.com/lmendo/MATL), 16 bytes
```
365:Z^!tXM=s>~Ym
```
First input is `N`, second is `k`.
[**Try it online!**](http://matl.tryitonline.net/#code=MzY1OlpeIXRYTT1zPn5ZbQ&input=Mgoy)
This is an enumeration-based approach, like [Dennis' Jelly answer](https://codegolf.stackexchange.com/a/82538/36398), so input numbers should be kept small due to memory limitations.
```
365: % Vector [1 2 ... 365]
Z^ % Take N implicitly. Cartesian power. Gives a 2D array with each
% "combination" on a row
! % Transpose
t % Duplicate
XM % Mode (most frequent element) of each column
= % Test for equality, element-wise with broadcast. For each column, gives
% true for elements equal to that column's mode, false for the rest
s % Sum of each column. Gives a row vector
>~ % Take k implicitly. True for elements equal or greater than k
Ym % Mean of each column. Implicitly display
```
[Answer]
# [Jelly](http://github.com/DennisMitchell/jelly), ~~17~~ 16 [bytes](https://github.com/DennisMitchell/jelly/wiki/Code-page)
```
ĠZL
365ṗÇ€<¬µS÷L
```
Extremely inefficient. [Try it online!](http://jelly.tryitonline.net/#code=xKBaTAozNjXhuZfDh-KCrDzCrMK1U8O3TA&input=&args=Mg+Mg) (but keep **N** below **3**)
### How it works
```
365ṗÇ€<¬µS÷L Main link. Left argument: N. Right argument: K
365ṗ Cartesian product; generate all lists of length N that consist of
elements of [1, ..., 365].
Ç€ Map the helper link over all generated lists. It returns the highest
amount of people that share a single birthday.
< Compare each result with K.
¬ Negate.
µS÷L Take the mean by dividing the sum by the length.
ĠZL Helper link. Argument: A (list of integers)
Ġ Group the indices have identical values in A.
Z Zip; transpose rows with columns.
L Take the length of the result, thus counting columns.
```
[Answer]
# J, ~~41~~ 36 bytes
```
(+/%#)@(<:365&(#~>./@(#/.~)@#:i.@^))
```
Straight-forward approach similar to the others. Runs into memory issues at **n > 3**.
## Usage
Takes the value of `k` on the LHS and `n` on the RHS.
```
f =: (+/%#)@(<:365&(#~>./@(#/.~)@#:i.@^))
0 f 0
0
0 f 1
1
1 f 1
1
0 f 2
1
1 f 2
1
2 f 2
0.00273973
0 f 3
1
1 f 3
1
2 f 3
0.00820417
3 f 3
7.5061e_6
```
On my pc, using an i7-4770k and the timer foreign `6!:2`, computing for **n = 3** requires about 25 seconds.
```
timer =: 6!:2
timer '2 f 3'
24.7893
timer '3 f 3'
24.896
```
## Explanation
```
(+/%#)@(<:365&(#~>./@(#/.~)@#:i.@^)) Input: k on LHS, n on RHS
365& The number 365
#~ Create n copies of 365
^ Calculate 365^n
i.@ The range [0, 1, ..., 365^n-1]
#: Convert each value in the range to base-n and pad
with zeroes to the right so that each has n digits
(#/.~)@ Find the size of each set of identical values
>./@ Find the max size of each
<: Test each if greater than or equal to k
(+/%#)@ Apply to the previous result
+/ Find the sum of the values
# Count the number of values
% Divide the sum by the count and return
```
] |
[Question]
[
We don't have a single challenge about drawing a real 3 dimensional cube, so here it goes:
# Challenge
Your task is to draw a rotated, cube with perspective. It can be in a separate window or as an image.
# Input
Your input is 3 separate numbers between 0 and 359.99... These represent the rotation around the x, y and z axis in degrees.
```
0 0 0
30 0 40
95 320 12
```
# Output
You can either display it in a separate window or save an image. You can use any type of display (vector based, rasterized, etc.).
Edit: ASCII is allowed too, to allow golfing languages with only textual output.
The output for rasterized or ASCII graphics must be at least 50\*50 (pixels for rasterization, characters for ASCII)
# Additional information
The positive z axis points out from the window, the x axis is horizontal, and the y axis is vertical. Basically the OpenGL standard.
Rotations are counter-clockwise if you look at the cube in the negative direction of a specific axis, e.g looking down for the y axis.
The camera should be on the z axis at a reasonable distance from the cube in the negative z direction, the cube should be at (0;0;0). The. cube also needs to be fully visible, and take up at least 50% of the drawing frame. The camera should look in the positive z direction at the cube.
The rotations of the cube get applied in the x->y->z order.
The cube is rotated around it's center, it doesn't move.
To project a cube in 2d space, you need to divide the x and y coordinates of the cube with the distance parallel to the z-axis between the point and the camera.
# Rules
Rendering libraries are allowed, but the vertices need to be defined in the code. No 3d cube model class.
# Test cases
[](https://i.stack.imgur.com/bEOH3.png)
[Answer]
## HTML/CSS/JS, 739 bytes, probably non-competing
But I just wanted to show off CSS 3D transforms.
```
w=_=>o.style.transform=`rotateZ(${z.value}deg) rotateY(${y.value}deg) rotateX(${-x.value}deg)`
```
```
input {
width: 5em;
}
#c{width:90px;height:90px;margin:90px;position:relative;perspective:180px}#o{position:absolute;width:90px;height:90px;transform-style:preserve-3d;transform-origin:45px 45px 0px;}#o *{position:absolute;width:90px;height:90px;border:2px solid black}#f{transform:translateZ(45px)}#b{transform:rotateX(180deg)translateZ(45px)}#r{transform:rotateY(90deg)translateZ(45px)}#l{transform:rotateY(-90deg)translateZ(45px)}#u{transform:rotateX(90deg)translateZ(45px)}#d{transform:rotateX(-90deg)translateZ(45px)}
```
```
<div oninput=w()>
X:<input id="x" type="number" value="0" min="0" max="360">
Y:<input id="y" type="number" value="0" min="0" max="360">
Z:<input id="z" type="number" value="0" min="0" max="360">
</div>
<!-- Above code for ease of use of snippet. Golfed version: <div oninput=w()><input id=x><input id=y><input id=z></div> -->
<div id=c><div id=o><div id=f></div><div id=b></div><div id=r></div><div id=l></div><div id=u></div><div id=d>
```
[Answer]
# [Shoes](http://shoesrb.com/) (Ruby) ~~235~~ 231
Everything computed from scratch.
```
Shoes.app{p,a,b,c=ARGV.map{|j|j.to_f/90}
k=1+i="i".to_c
p=(0..3).map{|j|y,z=(k*i**(j+a)).rect
x,z=(((-1)**j+z*i)*i**b).rect
q=(x+y*i)*i**c
[90*(k+q/(z-4)),90*(k+q/(4+z))]}
4.upto(15){|j|line *(p[j%4][0].rect+p[(j+j/4)%4][1].rect)}}
```
Call from commandline eg `shoes cube3d.rb 0 30 0`
The idea is to simultaneously generate / rotate the four vertices of a tetrahedron in 3d. Then, as these are reduced to 2d, we generate the four vertices of the inverse tetrahedron (the total 8 vertices being those of the cube.) This gives 4 pairs of vertices corresponding to the 4 body diagonals. Finally the 2d vertices are connected by lines: each vertex of the original tetrahedron must be connected to each vertex of the inverse tetrahedron forming the 12 edges and 4 body diagonals of the cube. The ordering ensures the body diagonals are not plotted.
**Test cases output**
Note that, to be consistent with the last two test cases, rotation about the z axis is clockwise from the POV of the viewer. This seems to be in contradiction with the spec however. Rotation direction can be reversed by modifying `*i**c` -> `/i**c`
[](https://i.stack.imgur.com/TK4ZJ.png)
**ungolfed**
```
Shoes.app{
p,a,b,c=ARGV.map{|j|j.to_f/90} #Throw away first argument (script name) and translate next three to fractions of a right angle.
k=1+i="i".to_c #set up constants i=sqrt(-1) and k=1+i
p=(0..3).map{|j| #build an array p of 4 elements (each element wil be a 2-element array containing the ends of a body diagonal in complex number format)
y,z=(k*i**(j+a)).rect #generate 4 sides of square: 1+i,i-1,-1-i,-i+1, rotate about x axis by a, and store in y and z as reals
x,z=(((-1)**j+z*i)*i**b).rect #generate x axis displacements 1,-1,1,-1, rotate x and z about y axis by b, store in x and z as reals
q=(x+y*i)*i**c #rotate x and y about z axis, store result in q as complex number
[90*(k+q/(z-4)),90*(k+q/(4+z))]} #generate "far" vertex q/(4+z) and "near" vertex q/-(4-z) opposite ends of body diagonal in 2d format.
4.upto(15){|j| #iterate through 12 edges, use rect and + to convert the two complex numbers into a 4 element array for line method
line *(p[j%4][0].rect+ #cycle through 4 vertices of the "normal" tetrahedron
p[(j+j/4)%4][1].rect) #draw to three vertices of the "inverted" tetrahedron. j/4=1,2,3, never 0
} #so the three edges are drawn but the body diagonal is not.
}
```
Note that for historical reasons a scale factor of 90 is applied in line 9 (chosen to be the same as 90 degrees in line 2 for golfing) but in the end there was no golfing advantage in using this particular value, so it has become an arbitrary choice.
[Answer]
# Maple, ~~130+14~~ (in progress)
```
with(plots):f:=(X,Y,Z)->plot3d(0,x=0..1,y=0..1,style=contour,tickmarks=[0,0,0],labels=["","",""],axes=boxed,orientation=[Z,-X,Y]);
```
[](https://i.stack.imgur.com/TL0Tt.png)
This plots a constant function inside a box, then uses plot options to hide ticks, labels and the function itself. Adding `projection=.5` to the options brings the camera closer, enabling perspective view.
I wrote this before the specs were finalized and the rotation order is `x, y', z''` instead of `x, y, z`. Until I fix the angles, here is another solution
# POV-Ray, 182
```
#include"a.txt"
#include"shapes.inc"
camera{location 9*z look_at 0}
light_source{9*z color 1}
object{Wire_Box(<-2,-2,-2>,<2,2,2>,.01,0)texture{pigment{color rgb 1}}rotate<R.x,-R.y,-R.z>}
```
reads input through the `a.txt` file which should contain
`#declare R=<xx,yy,zz>;`
with `xx,yy,zz` being the rotation angles
[](https://i.stack.imgur.com/sGx3V.jpg)
] |
[Question]
[
## Description
Write a function `f(m, G)` that accepts as its arguments a mapping `m`, and a set/list of distinct, non-negative integers `G`.
`m` should map pairs of integers in `G` to new integers in `G`. (`G`, `m`) is guaranteed to form a finite [abelian group](https://en.wikipedia.org/wiki/Abelian_group), but any element of `G` may be the identity.
There is an important theorem that says:
>
> [[Each finite abelian group] is isomorphic to a direct product of cyclic groups of prime power order.](http://groupprops.subwiki.org/wiki/Finite_abelian_group#Definition)
>
>
>
`f` must return a list of prime powers `[p1, ... pn]` in ascending order such that 
## Examples
* `f((a, b) → (a+b) mod 4, [0, 1, 2, 3])` should return `[4]`, as the parameters describe the group **Z4**.
* `f((a, b) → a xor b, [0, 1, 2, 3])` should return `[2, 2]`, as the parameters describe a group isomorphic to **Z2 × Z2**.
* `f((a, b) → a, [9])` should return `[]`, as the parameters describe the trivial group; i.e., the product of zero cyclic groups.
* Define `m` as follows:
```
(a, b) → (a mod 3 + b mod 3) mod 3
+ ((floor(a / 3) + floor(b / 3)) mod 3) * 3
+ ((floor(a / 9) + floor(b / 9)) mod 9) * 9
```
Then `f(m, [0, 1, ..., 80])` should return `[3, 3, 9]`, as this group is isomorphic to **Z3 × Z3 × Z9**
## Rules
* `m` may either be a function (or function pointer to some function) `Int × Int → Int`, or a dictionary mapping pairs in `G × G` to new elements of `G`.
* `f` may take its parameters in the opposite order, i.e. you may also implement `f(G, m)`.
* Your implementation should *theoretically* work for arbitrarily large inputs, but need not actually be efficient.
* There is no limitation on using built-ins of any kind.
* Standard [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'") rules apply. Shortest code in bytes wins.
## Leaderboard
For your score to appear on the board, it should be in this format:
```
# Language, Bytes
```
```
var QUESTION_ID=67252,OVERRIDE_USER=3852;function answersUrl(e){return"http://api.stackexchange.com/2.2/questions/"+QUESTION_ID+"/answers?page="+e+"&pagesize=100&order=desc&sort=creation&site=codegolf&filter="+ANSWER_FILTER}function commentUrl(e,s){return"http://api.stackexchange.com/2.2/answers/"+s.join(";")+"/comments?page="+e+"&pagesize=100&order=desc&sort=creation&site=codegolf&filter="+COMMENT_FILTER}function getAnswers(){jQuery.ajax({url:answersUrl(answer_page++),method:"get",dataType:"jsonp",crossDomain:!0,success:function(e){answers.push.apply(answers,e.items),answers_hash=[],answer_ids=[],e.items.forEach(function(e){e.comments=[];var s=+e.share_link.match(/\d+/);answer_ids.push(s),answers_hash[s]=e}),e.has_more||(more_answers=!1),comment_page=1,getComments()}})}function getComments(){jQuery.ajax({url:commentUrl(comment_page++,answer_ids),method:"get",dataType:"jsonp",crossDomain:!0,success:function(e){e.items.forEach(function(e){e.owner.user_id===OVERRIDE_USER&&answers_hash[e.post_id].comments.push(e)}),e.has_more?getComments():more_answers?getAnswers():process()}})}function getAuthorName(e){return e.owner.display_name}function process(){var e=[];answers.forEach(function(s){var r=s.body;s.comments.forEach(function(e){OVERRIDE_REG.test(e.body)&&(r="<h1>"+e.body.replace(OVERRIDE_REG,"")+"</h1>")});var a=r.match(SCORE_REG);a&&e.push({user:getAuthorName(s),size:+a[2],language:a[1],link:s.share_link})}),e.sort(function(e,s){var r=e.size,a=s.size;return r-a});var s={},r=1,a=null,n=1;e.forEach(function(e){e.size!=a&&(n=r),a=e.size,++r;var t=jQuery("#answer-template").html();t=t.replace("{{PLACE}}",n+".").replace("{{NAME}}",e.user).replace("{{LANGUAGE}}",e.language).replace("{{SIZE}}",e.size).replace("{{LINK}}",e.link),t=jQuery(t),jQuery("#answers").append(t);var o=e.language;/<a/.test(o)&&(o=jQuery(o).text()),s[o]=s[o]||{lang:e.language,user:e.user,size:e.size,link:e.link}});var t=[];for(var o in s)s.hasOwnProperty(o)&&t.push(s[o]);t.sort(function(e,s){return e.lang>s.lang?1:e.lang<s.lang?-1:0});for(var c=0;c<t.length;++c){var i=jQuery("#language-template").html(),o=t[c];i=i.replace("{{LANGUAGE}}",o.lang).replace("{{NAME}}",o.user).replace("{{SIZE}}",o.size).replace("{{LINK}}",o.link),i=jQuery(i),jQuery("#languages").append(i)}}var ANSWER_FILTER="!t)IWYnsLAZle2tQ3KqrVveCRJfxcRLe",COMMENT_FILTER="!)Q2B_A2kjfAiU78X(md6BoYk",answers=[],answers_hash,answer_ids,answer_page=1,more_answers=!0,comment_page;getAnswers();var SCORE_REG=/<h\d>\s*([^\n,]*[^\s,]),.*?(\d+)(?=[^\n\d<>]*(?:<(?:s>[^\n<>]*<\/s>|[^\n<>]+>)[^\n\d<>]*)*<\/h\d>)/,OVERRIDE_REG=/^Override\s*header:\s*/i;
```
```
body{text-align:left!important}#answer-list,#language-list{padding:10px;width:290px;float:left}table thead{font-weight:700}table td{padding:5px}
```
```
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <link rel="stylesheet" type="text/css" href="//cdn.sstatic.net/codegolf/all.css?v=83c949450c8b"> <div id="answer-list"> <h2>Leaderboard</h2> <table class="answer-list"> <thead> <tr><td></td><td>Author</td><td>Language</td><td>Size</td></tr></thead> <tbody id="answers"> </tbody> </table> </div><div id="language-list"> <h2>Winners by Language</h2> <table class="language-list"> <thead> <tr><td>Language</td><td>User</td><td>Score</td></tr></thead> <tbody id="languages"> </tbody> </table> </div><table style="display: none"> <tbody id="answer-template"> <tr><td>{{PLACE}}</td><td>{{NAME}}</td><td>{{LANGUAGE}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr></tbody> </table> <table style="display: none"> <tbody id="language-template"> <tr><td>{{LANGUAGE}}</td><td>{{NAME}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr></tbody> </table>
```
[Answer]
# Matlab, 326 bytes
With some group theory the idea is quite simple: Here the TL;DR Calculate all possible orders of elements of the group. Then find the biggest subgroup of a certain prime power order and "factorize" it out of the group, rinse, repeat.
```
function r=c(h,l)
%factorize group order
N=numel(L);
f=factor(N);
P=unique(f); %prime factors
for k=1:numel(P);
E(k)=sum(f==P(k)); %exponents of unique factors
end;
%calculate the order O of each element
O=L*0-1;
l=L;
for k=2:N+1;
l=h(l,L);
O(l==L & O<0)=k-1
end;
%%
O=unique(O); % (optional, just for speedupt)
R=[];
% for each prime,find the highest power that
% divides any of the orders of the element, and
% each time substract that from the remaining
% exponent in the prime factorization of the
% group order
for p=1:nnz(P); % loop over primes
while E(p)>1; % loop over remaining exponent
for e=E(p):-1:1; % find the highest exponent
B=mod(O,P(p)^e)==0;
if any(B)
R=[R,P(p)^e]; % if found, add to list
O(B)=O(B)/(P(p)^e);
E(p)=E(p)-e;
break;
end;
end;
end;
if E(p)==1;
R=[R,P(p)];
end;
end;
r=sort(R)
```
Example inputs:
```
L = 0:3;
h=@(a,b)mod(a+b,4);
h=@(a,b)bitxor(a,b);
L = 0:80;
h=@(a,b)mod(mod(a,3)+mod(b,3),3)+mod(floor(a/3)+floor(b/3),3)*3+ mod(floor(a/9)+floor(b/9),9)*9;
```
Golfed version:
```
function r=c(h,l);N=numel(L);f=factor(N);P=unique(f);for k=1:numel(P);E(k)=sum(f==P(k));end;O=L*0-1;l=L;for k=2:N+1;l=h(l,L);O(l==L&O<0)=k-1;end;R=[];for p=1:nnz(P);while E(p)>1;for e=E(p):-1:1;B=mod(O,P(p)^e)==0; if any(B);R=[R,P(p)^e]; O(B)=O(B)/(P(p)^e);E(p)=E(p)-e;break;end;end;end;if E(p)==1;R=[R,P(p)];end;end;r=sort(R)
```
[Answer]
## [GAP](http://gap-system.org), ~~159~~ 111 bytes
GAP allows us to simply construct a group by a multiplication table and compute its abelian invariants:
```
ai:= # the golfed version states the function w/o assigning it
function(m,G)
local t;
t:=List(G,a->List(G,b->Position(G,m(a,b))));
# t is inlined in the golfed version
return AbelianInvariants(GroupByMultiplicationTable(t));
end;
```
# The old version
The finitely presented group with generators G and relations a\*b=m(a,b) (for all a, b from G) is the group (G,m) we started with. We can create it and compute its abelian invariants with GAP:
```
ai:= # the golfed version states the function w/o assigning it
function(m,G)
local F,n,rels;
n:=Size(G);
F:=FreeGroup(n);
rels:=Union(Set([1..n],i->
Set([1..n],j->
F.(i)*F.(j)/F.(Position(G,m(G[i],G[j]))) ) ));
# rels is inlined in the golfed version
return AbelianInvariants(F/rels);
end;
```
# Examples
```
m1:=function(a,b) return (a+b) mod 4; end;
# I don't feel like implementing xor
m3:=function(a,b) return 9; end;
m4:=function(a,b)
return (a+b) mod 3 # no need for inner mod
+ ((QuoInt(a,3)+QuoInt(b,3)) mod 3) * 3
+ ((QuoInt(a,9)+QuoInt(b,9)) mod 9) * 9;
end;
```
Now we can do:
```
gap> ai(m1,[0..3]);
[ 4 ]
```
Actually, we are not restricted to using lists of integers. Using the correct domain, we can just use the general plus:
```
ai(\+,List(Integers mod 4));
[ 4 ]
```
So I can essentially do the second example using that its group is isomorphic to the additive group of the 2 dimensional vector space over the field with 2 elements:
```
gap> ai(\+,List(GF(2)^2));
[ 2, 2 ]
```
And the remaining examples:
```
gap> ai(m3,[9]);
[ ]
gap> ai(m4,[0..80]);
[ 3, 3, 9 ]
```
# Additional remarks
In the old version, m did not need to define a group composition for G. If m(a,b)=m(a,c), that just says that b=c. So we could do `ai(m1,[0..5])` and `ai(m3,[5..15])`. The new version will fail horrible in these cases, as will both versions if m returns values that are not in G.
If (G,m) is not abelian, we get a description of the abelianized version of it, that is its biggest abelian factor group:
```
gap> ai(\*,List(SymmetricGroup(4)));
[ 2 ]
```
This is what `AbelianInvariants` is usually used for, we would normally just call `AbelianInvariants(SymmetricGroup(4))`.
# The golfed version
```
function(m,G)return AbelianInvariants(GroupByMultiplicationTable(List(G,a->List(G,b->Position(G,m(a,b))))));end
```
] |
[Question]
[
The popular webcomic [Homestuck](http://www.mspaintadventures.com) makes use of a programming language called `~ATH` to destroy universes. While this code golf challenge is **not** to write a program to annihilate our existence, we will be destroying some more tame (albeit less interesting) entities: *variables*.
`~ATH` (pronounced "til death," notice how `~ath` is "tilde ath") works by creating a variable called `THIS`, executing a command with `EXECUTE`, and finishing the program with `THIS.DIE()`. A wiki page for the language's use in Homestuck can be found [here](http://mspaintadventures.wikia.com/wiki/~ATH). The goal of this challenge will be to create a `~ATH` interpreter.
For the sake of the challenge, I'm going to create some details of `~ATH` that don't really exist but make it (somewhat) useful.
* The language will only work with integers, which are declared with `import <variable name>;`. The variable will automatically be set to a value of 0. Only one variable at a time can be imported.
* A variable `x` can be copied by writing `bifurcate x[y,z];`, which will delete the variable `x` and replace it with identical variables `y` and `z`. Note that it cannot create a variable with the same name as the one deleted. Essentially, a variable is renamed, then a copy of the variable with a different name is created. This seems like a stupid feature, but stupidity is [very](http://www.mspaintadventures.com/?s=6&p=003552) deeply [ingrained](http://www.mspaintadventures.com/?s=6&p=005289) in Homestuck.
* The syntax for writing a program that executes code on `x` is `~ATH(x){EXECUTE(<code>)}`. If you want to execute code on two variables simultaneously, the code becomes nested, like this: `~ATH(x){~ATH(y){EXECUTE(<code>)}}`. All commands in `<code>` will be executed on both `x` and `y`.
* Now let's move onto commands. `+` increments relevant variable(s) by 1 and `-` decrements them by 1. And... that's it.
* The final feature of `~ATH` is that it kills whatever it works with. Variables are printed in the format `<name>=<value>` (followed by a newline) at the command `[<name>].DIE();`. Afterwards, the program prints the word `DIE <name>` and a newline a number of times equal to the absolute value of the value of the variable. When variables are killed simultaneously with `[<name1>,<name2>].DIE();` (you can have as many variables killed as you want, so long as they exist), the `DIE()` command is executed on the variables sequentially.
**Example programs**
Program 1:
```
import sollux; //calls variable "sollux"
import eridan; //calls variable "eridan"
~ATH(sollux){EXECUTE(--)} //sets the value of "sollux" to -2
~ATH(eridan){EXECUTE(+++++)} //sets the value of "eridan" to 5
[sollux].DIE(); //kills "sollux", prints "DIE sollux" twice
~ATH(eridan){EXECUTE(+)} //sets the value of "eridan" to 6
[eridan].DIE(); //kills "eridan", prints "DIE eridan" 6 times
```
Output:
```
sollux=-2
DIE sollux
DIE sollux
eridan=6
DIE eridan
DIE eridan
DIE eridan
DIE eridan
DIE eridan
DIE eridan
```
Program 2:
```
import THIS; //calls variable "THIS"
~ATH(THIS){EXECUTE(++++)} //sets the value of "THIS" to 4
bifurcate THIS[THIS1,THIS2]; //deletes "THIS", creates variables "THIS1" and "THIS2" both equal to 4
~ATH(THIS1){EXECUTE(++)} //sets the value of "THIS1" to 6
[THIS1,THIS2].DIE(); //kills "THIS1" and "THIS2", prints "DIE THIS1" 6 times then "DIE THIS2" 4 times
import THAT; //calls variable "THAT"
bifurcate THAT[THESE,THOSE]; //deletes "THAT", creates variables "THESE" and "THOSE"
~ATH(THESE){~ATH(THOSE){EXECUTE(+++)}EXECUTE(++)} //sets the value of "THESE" and "THOSE" to 3, then sets the value of "THESE" to 5
[THESE,THOSE].DIE(); //kills "THESE" and "THOSE", prints "DIE THESE" 5 times then "DIE THOSE" 3 times
```
Output:
```
THIS1=6
DIE THIS1
DIE THIS1
DIE THIS1
DIE THIS1
DIE THIS1
DIE THIS1
THIS2=4
DIE THIS2
DIE THIS2
DIE THIS2
DIE THIS2
THESE=5
DIE THESE
DIE THESE
DIE THESE
DIE THESE
DIE THESE
THOSE=3
DIE THOSE
DIE THOSE
DIE THOSE
```
---
This is code golf, so standard rules apply. Shortest code in bytes wins.
[Answer]
# Python 2.7.6, ~~1244~~ ~~1308~~ ~~1265~~ ~~1253~~ ~~1073~~ ~~1072~~ ~~1071~~ ~~1065~~ ~~1064~~ 1063 bytes
Alright, I'm not breaking any records here but this is about the smallest Python will go insofar as reading input all at once from a file rather than sequentially over time. I'll try to one-up this later in a different language (and an interpreter, not just a parser). Until then, enjoy the disgustingly horrid monstrosity.
*Note*: opens a file called `t` in the working directory. To make it open a command line argument, add `import sys` to the top of the file and change `'t'` to `sys.argv[1]`
```
n=s='\n';m=',';X='[';Y=']';c=';';A='~ATH';D='import';b,g,k=[],[],[];r=range;l=len;f=open('t','r').read().split(n)
def d(j,u):
p=[]
for e in j:
if e!=u:p.append(e)
return''.join(p)
for h in r(l(f)):f[h]=f[h].split('//')[0].split()
while[]in f:f.remove([])
for h in r(l(f)):
i=f[h]
if i[0]==D and l(i)==2and i[1][l(i[1])-1]==c and d(i[1],c)not in b:g.append(0);b.append(d(i[1],c))
elif i[0].startswith(A):
i=i[0].split('){')
for e in r(l(i)):
if i[e].startswith(A):
i[e]=i[e].split('(')
if i[0][1]in b:g[b.index(i[0][1])]+=(i[1].count('+')-i[1].count('-'))
elif i[0].startswith('bifurcate')and l(i)==2and i[1][l(i[1])-1]==c:
i=i[1].split(X)
if i[0] in b:
z=d(d(i[1],c),Y).split(m)
for e in r(l(z)):g.append(g[b.index(i[0])]);b.append(z[e])
g.remove(g[b.index(i[0])]);b.remove(i[0])
elif i[0].startswith(X)and i[0].endswith('.DIE();')and l(i)==1:
z=d(i[0],X).split(Y)[0].split(m)
for e in r(l(z)):
k.append((z[e],g[b.index(z[e])]))
for e in r(l(k)):k0=k[e][0];k1=k[e][1];s+=k0+'='+str(k1)+n+('DIE '+k0+n)*abs(k1)
print s
```
[Answer]
## Python 2, ~~447~~ ~~475~~ ~~463~~ 443 bytes
```
exec("eNp1UUtrAjEQvu+vCEshiYnrxl7KbqOUVmjvCoUkxUdiG7BRkpW2iP3tTVwrReppMsx8r4l936x9A8JXoN5kmu/2WeCxK0KjrSu8mWmEs0Ad96YI27lDPu/1is7wKqcQ0kBLenM+ty0nilu4zqnPtYCSQcXL2P2LmNvl1i9mjWlBUhwKbRt14uhHjlSvjzVy1tqswO/7AjsSpKtwIpGvt2zALqyNnkf3k/FIolb2ACjlpe2jR6lk8fAUQbKNulx7YIF1IDkqwmZlGwQpxNXGW9cASyCHZKqFVVOCoJQOEhjxABKLO7N5QGmET5qOs/Qfoqq6TGUfb3ZlgKvOnOxTwJKpDq6HSLzsVfK1k7g1iB7Hd9/JWh3T9wclkYwTlY4odP0nnvk0C3RUwj95/ZUq".decode('base64').decode('zip'))
```
It turns out zipping and encoding the program base64 still saves bytes over the normal version. For comparison, here's the normal one:
```
import sys,re
d={}
s=sys.stdin.read()
s,n=re.subn(r"//.*?$",'',s,0,8)
s,n=re.subn(r"import (.*?);",r"d['\1']=0;",s,0,8)
s,n=re.subn(r"bifurcate (.*?)\[(.*?),(.*?)\];",r"d['\2']=d['\3']=d['\1'];del d['\1'];",s,0,8)
s,n=re.subn(r"([+-])",r"\g<1>1",s,0,8)
s,n=re.subn(r"EXECUTE\((.*?)\)",r"0\1",s,0,8)
s,n=re.subn(r"\[(.*?)\]\.DIE\(\);",r"for i in '\1'.split(','):print i+'='+`d[i]`+('\\n'+'DIE '+i)*abs(d[i])",s,0,8)
n=1
s=s[::-1]
while n:s,n=re.subn(r"\}([+-01]*);?([^}]*?)\{\)(.*?)\(HTA~",r";\g<2>0+\1=+]'\3'[d;\1",s,0,8)
exec(s[::-1])
```
Basically the "regexy wands of magic" solution that was desired. Reads in the entire program from stdin as a single string, replaces ~ATH expressions with Python expressions that do the described semantics, and exec()s the resulting string.
To see what it's doing, look at the python program the second provided test program gets translated to:
```
d['THIS']=0;
0+1+1+1+1;d['THIS']+=0+1+1+1+1+0;
d['THIS1']=d['THIS2']=d['THIS'];del d['THIS'];
0+1+1;d['THIS1']+=0+1+1+0;
for i in 'THIS1,THIS2'.split(','):print i+'='+`d[i]`+('\n'+'DIE '+i)*abs(d[i])
d['THAT']=0;
d['THESE']=d['THOSE']=d['THAT'];del d['THAT'];
0+1+1;d['THESE']+=0+1+1+00+1+1+1;d['THOSE']+=0+1+1+1+0;
for i in 'THESE,THOSE'.split(','):print i+'='+`d[i]`+('\n'+'DIE '+i)*abs(d[i])
```
It's a good thing that `00 == 0` :P
Obviously, a few bytes could be saved by exploiting ambiguity in the rules. For instance, it isn't said what should happen in the event someone tries to `DIE()` a variable that hasn't been `import`ed, or that has already been `bifurcate`d. My guess based on the description was that there should be an error. If no error is required, I could remove the `del` statement.
EDIT: Fixed a bug that the provided test cases didn't test for. Namely, the way it was, every `~ATH` block reset the variable to zero before incrementing it. It cost me 28 bytes to fix that. If anyone sees a better way to replace `~ATH` blocks, I'd love to know it.
EDIT 2: Saved 12 bytes by unrolling the regex loop, making them all subns and letting the compression take care of the repetition.
EDIT 3: Saved 20 more bytes by replacing the inner `for` loop with a string multiplication.
] |
[Question]
[
You saved the day with your [prime sequence code](https://codegolf.stackexchange.com/q/59736/42963), and the math teacher loved it. So much so that a new challenge was posed to the librarian (a/k/a, your boss). Congratulations, you get to code the solution so the librarian can once again impress the math teacher.
Start with the sequence of natural numbers in base-10, \$\mathbb N\$
>
> 0, 1, 2, 3, 4, 5, 6 ...
>
>
>
Excluding `0` and `1`, every number in this sequence either is prime, \$\mathbb P\$
>
> 2, 3, 5, 7, 11, 13 ...
>
>
>
or composite, \$\mathbf C\$
>
> 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20 ...
>
>
>
Reflecting on how the librarian thought to insert an integer digit into the decimal expansion of a number from \$\mathbb P\$, the math teacher instead created a function \$G(x,y)\$ that takes a number \$x\$ from \$\mathbb N\$ with \$1 \le x \le 9\$ and a number \$y\$ from \$\mathbf C\$ and inserts \$x\$ into the decimal expansion of \$y\$ in every position, in order left-to-right, selecting only unique numbers.
For example, \$G(3,14)\$ is \$314, 134, 143\$. However, \$G(1,14)\$ is only \$114, 141\$, as whether you prepend or insert the \$1\$ into \$14\$, the same number \$114\$ is generated.
The math teacher wondered how many times you'd have to do these permutations before you get a number that's in \$\mathbb P\$, if you took \$x\$ in increasing order. The math teacher called this the **Composite-Prime Index** of a number, and wrote it as \$\text{CPI}(y)\$.
For example, \$4\$ only needs to be done twice: \$14, 41\$, since \$41\$ is prime, so \$\text{CPI}(4)\$ is \$2\$. However, \$8\$ needs to be done 6 times, \$18, 81, 28, 82, 38, 83\$ before reaching \$83\$ as a prime number, so \$\text{CPI}(8)\$ is \$6\$.
Your task is to write code that will output this **Composite-Prime Index**, given an input number.
## Input
* A single integer \$y\$, such that \$y\$ is in \$\mathbf C\$, input via function argument, STDIN, or equivalent.
* For the purposes of calculation, you can assume \$y\$ will fit in usual integer ranges (e.g., assume \$2^{31}-1\$ as an upper bound).
* Behavior for \$y\$ not in *C* is undefined.
## Output
The resultant **Composite-Prime Index**, calculated as described above, output to STDOUT or equivalent, with two exceptions:
* If the *very last* permutation (i.e., appending \$9\$ to \$y\$) is the one that results in a prime, output `-1`. An example, expanded below, is \$y=14\$.
* If there is no permutation (i.e., \$G(x,y)\$ is a subset of \$\mathbf C\$ for all \$1 \le x \le 9\$), output `0`. An example, expanded below, is \$y=20\$.
## Examples
```
y -> operations : output
4 -> 14, 41 : 2
6 -> 16, 61 : 2
8 -> 18, 81, 28, 82, 38, 83 : 6
9 -> 19 : 1
10 -> 110, 101 : 2
12 -> 112, 121, 212, 122, 312, 132, 123, 412, 142, 124, 512, 152, 125, 612, 162, 126, 712, 172, 127 : 19
14 -> 114, 141, 214, 124, 142, 314, 134, 143, 414, 144, 514, 154, 145, 614, 164, 146, 714, 174, 147, 814, 184, 148, 914, 194, 149 : -1
15 -> 115, 151 : 2
16 -> 116, 161, 216, 126, 162, 316, 136, 163 : 8
18 -> 118, 181 : 2
20 -> 120, 210, 201, 220, 202, 320, 230, 203, 420, 240, 204, 520, 250, 205, 620, 260, 206, 720, 270, 207, 820, 280, 208, 920, 290, 209 : 0
```
## Restrictions
* This is code-golf, since you'll need to transcribe this to an index card so the librarian can show the math teacher, and your hand cramps easily.
* Standard loophole restrictions apply. The librarian doesn't tolerate cheaters.
## Leaderboard
```
var QUESTION_ID=63191,OVERRIDE_USER=42963;function answersUrl(e){return"http://api.stackexchange.com/2.2/questions/"+QUESTION_ID+"/answers?page="+e+"&pagesize=100&order=desc&sort=creation&site=codegolf&filter="+ANSWER_FILTER}function commentUrl(e,s){return"http://api.stackexchange.com/2.2/answers/"+s.join(";")+"/comments?page="+e+"&pagesize=100&order=desc&sort=creation&site=codegolf&filter="+COMMENT_FILTER}function getAnswers(){jQuery.ajax({url:answersUrl(answer_page++),method:"get",dataType:"jsonp",crossDomain:!0,success:function(e){answers.push.apply(answers,e.items),answers_hash=[],answer_ids=[],e.items.forEach(function(e){e.comments=[];var s=+e.share_link.match(/\d+/);answer_ids.push(s),answers_hash[s]=e}),e.has_more||(more_answers=!1),comment_page=1,getComments()}})}function getComments(){jQuery.ajax({url:commentUrl(comment_page++,answer_ids),method:"get",dataType:"jsonp",crossDomain:!0,success:function(e){e.items.forEach(function(e){e.owner.user_id===OVERRIDE_USER&&answers_hash[e.post_id].comments.push(e)}),e.has_more?getComments():more_answers?getAnswers():process()}})}function getAuthorName(e){return e.owner.display_name}function process(){var e=[];answers.forEach(function(s){var r=s.body;s.comments.forEach(function(e){OVERRIDE_REG.test(e.body)&&(r="<h1>"+e.body.replace(OVERRIDE_REG,"")+"</h1>")});var a=r.match(SCORE_REG);a&&e.push({user:getAuthorName(s),size:+a[2],language:a[1],link:s.share_link})}),e.sort(function(e,s){var r=e.size,a=s.size;return r-a});var s={},r=1,a=null,n=1;e.forEach(function(e){e.size!=a&&(n=r),a=e.size,++r;var t=jQuery("#answer-template").html();t=t.replace("{{PLACE}}",n+".").replace("{{NAME}}",e.user).replace("{{LANGUAGE}}",e.language).replace("{{SIZE}}",e.size).replace("{{LINK}}",e.link),t=jQuery(t),jQuery("#answers").append(t);var o=e.language;/<a/.test(o)&&(o=jQuery(o).text()),s[o]=s[o]||{lang:e.language,user:e.user,size:e.size,link:e.link}});var t=[];for(var o in s)s.hasOwnProperty(o)&&t.push(s[o]);t.sort(function(e,s){return e.lang>s.lang?1:e.lang<s.lang?-1:0});for(var c=0;c<t.length;++c){var i=jQuery("#language-template").html(),o=t[c];i=i.replace("{{LANGUAGE}}",o.lang).replace("{{NAME}}",o.user).replace("{{SIZE}}",o.size).replace("{{LINK}}",o.link),i=jQuery(i),jQuery("#languages").append(i)}}var ANSWER_FILTER="!t)IWYnsLAZle2tQ3KqrVveCRJfxcRLe",COMMENT_FILTER="!)Q2B_A2kjfAiU78X(md6BoYk",answers=[],answers_hash,answer_ids,answer_page=1,more_answers=!0,comment_page;getAnswers();var SCORE_REG=/<h\d>\s*([^\n,]*[^\s,]),.*?(\d+(?:[.]\d+)?)(?=[^\n\d<>]*(?:<(?:s>[^\n<>]*<\/s>|[^\n<>]+>)[^\n\d<>]*)*<\/h\d>)/,OVERRIDE_REG=/^Override\s*header:\s*/i;
```
```
body{text-align:left!important}#answer-list,#language-list{padding:10px;width:290px;float:left}table thead{font-weight:700}table td{padding:5px}
```
```
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <link rel="stylesheet" type="text/css" href="//cdn.sstatic.net/codegolf/all.css?v=83c949450c8b"> <div id="answer-list"> <h2>Leaderboard</h2> <table class="answer-list"> <thead> <tr><td></td><td>Author</td><td>Language</td><td>Size</td></tr></thead> <tbody id="answers"> </tbody> </table> </div><div id="language-list"> <h2>Winners by Language</h2> <table class="language-list"> <thead> <tr><td>Language</td><td>User</td><td>Score</td></tr></thead> <tbody id="languages"> </tbody> </table> </div><table style="display: none"> <tbody id="answer-template"> <tr><td>{{PLACE}}</td><td>{{NAME}}</td><td>{{LANGUAGE}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr></tbody> </table> <table style="display: none"> <tbody id="language-template"> <tr><td>{{LANGUAGE}}</td><td>{{NAME}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr></tbody> </table>
```
[Answer]
## Haskell, ~~166~~ 161 bytes
```
p n=mod(product[1..n-1]^2)n>0
q=p.read
n#c=[h++c:t|i<-[0..length n],(h,t)<-[splitAt i n]]
[y]%i|q y= -1|1<2=0
(y:z)%i|q y=i|1<2=z%(i+1)
f n=((n#)=<<['1'..'9'])%1
```
Usage examples: `f "8"` -> `6`, `f "14"`-> `-1`, `f "20"`-> `0`.
How it works: `p` is the primality test (stolen from @Mauris' [answer](https://codegolf.stackexchange.com/a/57704/34531) in a different challenge). `q` a wrapper for `p` to convert types from strings to integer. `n # c` inserts `c` at every position in `n`. `%` takes a list of numbers and an index `i`. When the first element of the list is prime, return `i`, else recure with the tail of the list and `i+1`. Stop when there's a single element left and return `-1` if it's prime and `0` otherwise.
[Answer]
# Pyth, 35 bytes
```
&sKm}dPdsm{msj`dcz]khlzS9|%hxK1lK_1
```
[Test suite](https://pyth.herokuapp.com/?code=%26sKm%7DdPdsm%7Bmsj%60dcz%5DkhlzS9%7C%25hxK1lK_1&input=16&test_suite=1&test_suite_input=4%0A6%0A8%0A9%0A10%0A12%0A14%0A15%0A16%0A18%0A20&debug=0)
[Answer]
## [Minkolang 0.11](https://github.com/elendiastarman/Minkolang), 85 bytes
```
n1(l*$d`)d9[i3G(0c2c$%$r2c*l*2c3c1+*++2gl:d2G)2gx1c2G3gx]r3XS(2M4&I)N.ikI1-4&1~N.1+N.
```
[Try it here.](http://play.starmaninnovations.com/minkolang/?code=n1%28l*%24d%60%29d9%5Bi3G(0c2c%24%25%24r2c*l*2c3c1%2B*%2B%2B2gl%3Ad2G)2gx1c2G3gx%5Dr3XS(2M4%26I)N%2EikI1-4%261%7EN.1%2BN.&input=12)
### Explanation (coming soon)
```
n Take integer from input (say, n)
1( Calculate smallest power of 10 greater than n (say, a)
l* Multiply by 10
$d` Duplicate stack and push n>a
) Close while loop (ends when n<=a)
d Duplicates a (let's call it b)
9[ For loop that runs 9 times
i1+ Loop counter + 1 (say, i)
3G Puts the loop counter in position 3
( Opens while loop
0c2c$% Copies n and b and pushes n//b, n%b
$r Swaps top two elements of stack
2c*l* Copies b and multiplies by 10
2c3c* Copies b and i and multiplies them
++ Adds it all together (inserts i)
2gl: Gets b and divides by 10
d2G Duplicates and puts one copy back
) Closes while loop (breaks when b=0)
2gx Gets and dumps b
1c2G Copies a and puts it in b's place
3gx Get and dumps i
] Close for loop
r Reverses stack
3X Dumps the top three elements (namely, n, a, and b)
S Removes duplicates
( Opens while loop
2M Pushes 1 if top of stack is prime, 0 otherwise
4& Jump four spaces if prime
I)N. If the loop actually finishes, then all were composite,
so output 0 and stop.
ik Pushes loop counter and breaks
I1- Pushes length of stack minus 1 (0 if last one was prime)
4&1~N. If this is 0, pushes -1, outputs as integer, and stops.
1+N. Adds 1, outputs as integer, and stops.
```
[Answer]
# Javascript, 324 bytes
```
y=>(p=(n,c)=>n%c!=0?c>=n-1?1:p(n,++c):0,u=a=>a.filter((c,i)=>a.indexOf(c)==i),g=(x,y)=>u(((x,y,z)=>z.map((c,i)=>z.slice(0,i).join("")+x+z.slice(i).join("")).concat(y+x))(x,y,y.split(''))),h=(x,y)=>g(x,y).concat(x==9?[]:h(++x,y)),i=h(1,y).reduce((r,c,i)=>r?r:p(c,2)?i+1:0,0),console.log(p(y,2)||y<2?'':i==h(1,y).length?-1:i))
```
If y not in C, then STDOUT output is empty.
## Explanation
```
y=>(
//Prime Test function
p=(n,c)=>n%c!=0?c>=n-1?1:p(n,++c):0,
//Unique function
u=a=>a.filter((c,i)=>a.indexOf(c)==i),
//Generates numbers from a couple x and y
g=(x,y)=>u(((x,y,z)=>z.map((c,i)=>z.slice(0,i).join("")+x+z.slice(i).join("")).concat(y+x))(x,y,y.split(''))),
//Generates all possible numbers from y using recusion
h=(x,y)=>g(x,y).concat(x==9?[]:h(++x,y)),
//Check if any prime in the generated numbers
i=h(1,y).reduce((r,c,i)=>r?r:p(c,2)?i+1:0,0),
console.log(
//Is Y in C ?
p(y,2)||y<2?
''
:
// Check if the answer is not the last one
i==h(1,y).length?-1:i)
)
```
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), 25 bytes
```
D-ṭJœṖ€$jþ9ẎṖ€ḌQẒµL,-yi1$
```
[Try it online!](https://tio.run/##y0rNyan8/99F9@HOtV5HJz/cOe1R0xqVrMP7LB/u6oPwHu7oCXy4a9KhrT46upWZhir/jQwe7uh6uGP@4bYg68PtKkAl7v8B "Jelly – Try It Online")
+6 bytes to allow for:
>
> If the very last permutation (i.e., appending 9 to y) is the one that results in a prime, output -1
>
>
>
## How it works
```
D-ṭJœṖ€$jþ9ẎṖ€ḌQẒµL,-yi1$ - Main link. Takes n on the left
D - Digits of n
-ṭ - Append -1; Call this D
$ - To D:
J - Indices; Yield [1, 2, ..., len(D)]
€ - For each index i:
œṖ - Partition D at index i
9 - Generate the range [1,2,3,4,5,6,7,8,9]
þ - Pair up all pairs from the range and the partitions:
j - Join each partition with the corresponding integer
Ẏ - Tighten into a list of lists
Ṗ€ - Remove the -1 from each
Ḍ - Convert back to integers
Q - Deduplicate
Ẓ - Replace primes with 1 and composites with 0
µ - Call this list of bits B
L - Length of B
,- - Pair with -1
$ - To B:
i1 - Yield the first index of 1, or 0 if not found
y - If the index is equal to the length, replace with -1
```
] |
[Question]
[
### The Game
Recently, much of my time has been taken up by an addicting game on my phone, called Logic Dots, which inspired me to write this challenge. It's easier to explain the rules if I show you the game display, so here is a screenshot of an unsolved, and solved puzzle:


Now here, there are three main things to notice.
1. The game board (the 4x4 grid of squares in the center)
2. The required shapes (the linked dots in the second bar from the top, under the score and menu, etc.), which are all lines, or `a` by 1 rectangles
3. The numbers over the rows and columns, which denotes how many dots need to be in the column, for a solution
The objective of the game is to fit the required shapes into the grid. You can rotate the shapes, but they cannot go in diagonally.
In the solution, notice that all shapes are created exactly once (because they are only in the required shapes once), and in this case they are all horizontal but they can also be vertical. The pink filled in squares denote squares not used.
Here is a bigger, and slightly more complicated grid:


Notice that in the unsolved puzzle, there are already a few squares filled i.n The greyed out squares signify blocked squares that you **CANNOT** place a dot on. The dots with tails tell you that a dot is in that spot, and it links to **at least** one more dot in the direction of the tail, but not in any other direction (including the opposite direction).
### Notation
For the rest of this post, I will refer to the board using the following symbols:
* **<, >, ^, v -** Signifies a pre-placed dot with a tail extending in the direction of the point
* **\* -** Signifies a dot. If given on an unsolved grid (input), it is an individual shape. If in output, then it is connected to the dots around it.
* **# -** Signifies a blocked grid square (where you cannot place a dot)
* **-, | (hyphen and bar) -** Signify a dot with a right and left tail, and a dot with an up and down tail respectively
* \*\* (space character) -\*\* Signifies an empty space
Using these symbols, the latter example case (unsolved) can be represented as follows:
```
<
#
^ #
```
And the solution can be represented as:
```
*< * *
*
*
* *
* *#*
^ # *
```
Note that no two shapes can touch horizontally, vertically **or diagonally**, so the following case is not valid:
```
***
**
**
```
## Challenge
Your challenge is to solve any logic dots puzzle, from 4x4 to 9x9 inclusive. You will receive four lines of input, then the game board. The lines will be as follows:
* 1st line, Shapes - The shapes to find, each given in the form `sizexquantity` (eg. `3x2` for two shapes of length three) and separated by a space. Example line: `3x1 2x1 1x1`
* 2nd line, Columns - A space separated list of the required dot count for each column. Example line: `1 1 2 2`
* 3rd line, Rows- A space separated list of the required dot count for each row. Example line: `3 0 3 0`
* 4th line, Board size - A single integer, the board size, `B`
The board is then given, and is `B` lines of input representing the board using the notation mentioned above. For example, the complete input for the latter example case is as follows:
```
4x1 3x1 2x2 1x2
1 4 0 3 0 5
4 1 1 2 3 2
6
<
#
^ #
```
Your program will then output the solved board, in the same notation. The matching output for the above input is as follows:
```
** * *
*
*
* *
* *#*
* # *
```
Note that a game board can have multiple solutions. In this case, just output one valid solution. Also, your program must output a correct solution within 10 seconds on a reasonable desktop computer for a complicated 10x10 grid.
This is code golf, so least bytes wins.
---
# Test Cases
**Input 1**
```
3x2 1x4
2 2 3 1 2
4 0 3 0 3
5
#
#
*
```
**Output 1**
```
*** *
***#
#
* * *
```
**Input 2**
```
3x1 1x6
2 0 4 0 3
3 1 2 1 2
5
*
#
```
**Output 2**
```
* * *
*
* *
* #
* *
```
**Input 3**
```
5x1 4x1 2x1 1x2
1 2 3 3 2 2
0 5 0 4 0 4
6
#
-
#
<
```
**Output 3**
```
#
*****
****
#
* ** *
```
[Answer]
# Python 2: ~~766~~ ~~739~~ ~~696~~ ~~663~~ 633 bytes
```
def f(B,S,o=0):
if[]==S:print'\n'.join(B);exit()
s=S[0]
for i in r:
for j in R(Z-s+1):
if(B[i][j]in' '+'>v'[o])*(B[i][j+s-1]in' '+'<^'[o])*({' ','-|'[o]}>=set(B[i][j+1:j+s-1]))*all(B[x][y]in'# 'for x,y in [(x,y)for y in R(j-1,j+s+1)for x in i-1,i+1]+[(i,j-1),(i,j+s)]if 0<=x<Z>y>=0):q=B[:];q[i]=q[i][:j]+'*'*s+q[i][j+s:];q=(q,t(q))[o];any((t(q)+q)[k].count('*')>m[k]for k in R(Z+Z))or f(q,S[1:])
o or f(t(B),S,1)
y=raw_input;S=[];s=str.split
for i in s(y()):u,v=map(int,s(i,'x'));S+=[u]*v
m=map(int,s(y())+s(y()));Z=input();R=range;r=R(Z);B=[y()for _ in r];J=''.join;t=lambda x:map(J,zip(*x))
f(B,S[:len(S)-J(B).count('*')])
```
See it working online: [Ideone.com](http://ideone.com/wSZzkI) (The online version may be too slow for large and difficult grids, offline it should be fine)
Input is via stdin, just copy and past the lines from the OP (but be careful, stackexchange sometimes deletes spaces or lines).
Some basic ideas of this code:
It uses a recursive function `f`. `f` tries to place one shape at the board. For each possible location it calls itself with the modified board. There are 3 loops in it. `o` determines the orientation (2 - horizontal, 3 - vertical). It will always place the shape horizontal, therefore at the end of `o=2`, it will transpose the board with the function `t`. `i` is the row and `j` are all possible starting columns. Then a lot of checks happen, if the ends of the shape have valid chars, if the middle of the shape has valid chars and if the surrounding is empty.
[Answer]
# JavaScript (ES6) 661 ~~667 695 702 745 755 786 790 784 798~~
~~Work in progress, can be shortened.~~
Probably too slow on a complex grid. Maybe not.
**Edit** A bit longer, a lot faster.
**Edit 2** Bug fix, columns/rows check. Incidentally, now it's faster
The M function is the main. The w parameter is a multiline string with all the input. The function parses the input and prepare a starting board. Characters `<>^v|-*` in the starting board are replaced with `,`, each `,` has to be replaced with `*` in the correct solution.
The R function tries recursively to place all shapes in the board. When a shape is placed, it calls itself passing a shorter list of shapes and the modified board. When all shapes are placed, a solution can still be invalid if there are `,` not replaced by `*`.
The P function test if a shape can be placed a a given position and orientation. It checks all the costrains (inside the board, no overlap, no touch, valid row and column count)
```
M=w=>(
[x,c,r,z]=w=w[S='split'](n='\n'),
(b=[...w.slice(4).join(n)])
.map((c,p)=>~(k='*<>-*^v|'.indexOf(c))&&[(q=k>3?z:1,0),k&1&&-q,k&2&&q].map(o=>b[p+o]=0),
c=c[S](e=' '),r=r[S](e),w=z++,f='*',s='',x[S](e).map(v=>s+=v[0].repeat(v[2]))),
R=(s,b,x=0,y=0,n=s[0],V=i=>b[i]>'#',
P=(p,o,q,t,g,l,d=[...b])=>{
if(l<z-n&!V(p+o*l-o)&!V(p+o*l+o*n))
{
for(i=-1;v=d[p],++i<w;p+=o,t-=v==f)
if(i>=l&i-n<l)
for(v!=e&v!=0|[q,w,~z].some(w=>V(p+w)|V(p-w))?t=0:d[p]=f,j=o*i,u=k=0;
++k<z;(u+=d[j]==f)>g[i]?t=0:j+=q);
return t>=n&&d.join('')
}
})=>{
if(b){
if(!n)return~b.search(0)?0:b;
for(s=s.slice(1);y<w||(y=0,++x<w);++y)
if(h=R(s,P(y*z,1,z,r[y],c,x))||n>1&&R(s,P(x,z,1,c[x],r,y)))return h
}
})(s,b)
```
**Test** In FireFox/FireBug console
```
;['3x2 1x4\n2 2 3 1 2\n4 0 3 0 3\n5\n \n \n #\n # \n *\n'
,'3x1 1x6\n2 0 4 0 3\n3 1 2 1 2\n5\n* \n \n \n # \n \n'
,'5x1 4x1 2x1 1x2\n1 2 3 3 2 2\n0 5 0 4 0 4\n6\n# \n - \n \n \n # \n < \n'
,'4x1 3x1 2x2 1x2\n1 4 0 3 0 5\n4 1 1 2 3 2\n6\n < \n \n \n \n # \n ^ # \n']
.forEach(x=>console.log(x,M(x).replace(/ /g,'`'))) // space replaced with ` for clarity
```
*Output* (total execution time < 1sec)
```
3x2 1x4
2 2 3 1 2
4 0 3 0 3
5
#
#
*
***`*
`````
`***#
``#``
*`*`*
3x1 1x6
2 0 4 0 3
3 1 2 1 2
5
*
#
*`*`*
``*``
``*`*
*``#`
``*`*
5x1 4x1 2x1 1x2
1 2 3 3 2 2
0 5 0 4 0 4
6
#
-
#
<
#`````
`*****
``````
`****`
`#````
*`**`*
4x1 3x1 2x2 1x2
1 4 0 3 0 5
4 1 1 2 3 2
6
<
#
^ #
**`*`*
```*``
`````*
`*```*
`*`*#*
`*`#`*
```
] |
[Question]
[
The most recognizable [sliding puzzle](http://en.wikipedia.org/wiki/Sliding_puzzle) is the [fifteen puzzle](http://en.wikipedia.org/wiki/15_puzzle). It has a 4 by 4 grid, 15 tiles, and one empty grid space. The tiles can only move into the empty space and must always be in line with the grid.
Let's define a generalized sliding puzzle as a two-dimensional *W* wide by *H* high grid (*W*, *H* both positive integers) that contains some number of **identical unmarked** tiles (between 0 and *W*×*H* of them) snapped to the grid, arranged in any way (without overlapping), with empty grid spaces filling the rest of the area.
For example if *W* and *H* are 3 and a tile is `T` and an empty space is `E` one of many possible siding puzzle arrangements is
```
TTT
TET
EET
```
For these puzzles there are 4 possible moves: shove everything **up**, shove everything **down**, shove everything **left**, or shove everything **right**. 'Shoving' in some direction makes all the tiles travel in that direction as far as possible until they hit another tile or the grid boundary. Sometimes shoving will not change the layout of the grid,
If the example grid is shoved right the result is
```
TTT
ETT
EET
```
Shoved left the result is
```
TTT
TTE
TEE
```
Shoved down the result is
```
EET
TET
TTT
```
(notice that both the leftmost `T`'s moved)
Shoving up does not change the grid layout in this case.
Note that since the tiles are indistinguishable these puzzles do not have 'solved' states. Also note that a puzzle may start in a layout that is impossible to get back to once a shove has been made (e.g. one tile in the middle of a 3 by 3 grid).
# Challenge
Using only [printable ASCII](http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters) write two rectangular blocks of code, both *M* characters wide and *N* characters tall (for any positive integers *M*, *N*). One code block will represent a tile of a sliding puzzle, the other code block will represent an empty grid space.
Arranging these two code blocks into a *W* by *H* grid will create a code-represented sliding puzzle which can be saved as a text file and run as a normal program. When run, these kind of programs should prompt the user via stdin for a number from 1 to 4; **1 is for up, 2 down, 3 left, 4 right**. When the user types in their number and hits enter, the program calculates how to shove its source code tiles in that direction and saves the new puzzle layout in a file (either a new file or in the same file), then terminates.
This process can be repeated indefinitely with the new sliding puzzle code file generated after each shove.
# Example
Suppose my tile code block looks like this
```
// my
// tile
```
and my empty grid space code block looks like this
```
//empty
//space
```
(*M* = 7, *N* = 2, this is of course not actual code)
Any valid sliding puzzle arrangement of these two blocks should create a program in the language I'm using that can be run to let the user shove in some direction.
The code representation of the example grid is:
```
// my// my// my
// tile// tile// tile
// my//empty// my
// tile//space// tile
//empty//empty// my
//space//space// tile
```
So running this and pressing 2 (for down) then Enter would write this to another file (or the same file):
```
//empty//empty// my
//space//space// tile
// my//empty// my
// tile//space// tile
// my// my// my
// tile// tile// tile
```
That file could then be run and shoved in the same exact way.
# Notes
* Any code-representation of a *W* by *H* sliding puzzle should be runnable and be able to shove itself properly. This includes all grid sizes from 1 by 1 to some reasonable maximum (216 by 216 or more).
* **A program *may* read its own source code.** There are no quine-based restrictions. Comments of any sort are also fine.
* The program must prompt for a direction to shove in even if there are no tiles to shove or no tiles can be shoved. The prompt is simply a place to type in a number, no message is required.
* You may assume the input is always valid (1, 2, 3, or 4).
* Padding your code blocks with spaces is fine. Remember that they can only be printable ASCII, this mean no tabs and no newlines (besides the newlines that help form the code blocks).
* If your language does not support stdin use whatever input method seems closest.
* You can require that a newline be at the end of your code-puzzle files. (Or require that it not be there.)
* How you name new files is not important. `f.txt` or just `f` is fine.
* The two code blocks may not be identical.
# Scoring
The goal is to do this with the smallest code size (which is why this is tagged code-golf). The submission with the smallest code block area (*M*×*N*) is the winner. Tie-breaker goes to the highest voted answer.
*Related: [Code that runs the Game of Life on itself](https://codegolf.stackexchange.com/q/35974/26997)*
[Answer]
# [TECO](http://almy.us/teco.html), 153
Empty block:
```
0T@^Ux#EBx#27@:^Ux##MxA1^QUq^T%d/51%w"G153UsZ/QqUlQq/153Un|Qq%s/153UlZ/QqUn'Qd&1UhQl<.UpQn<Qh-\"F%c'TRQs:C>QpJQn<D-%c"L%c1-Qh\|Qh\'RQs:C>Qw"GC|153%pJ'>EX
```
Tile block:
```
1T@^Ux#EBx#27@:^Ux##MxA1^QUq^T%d/51%w"G153UsZ/QqUlQq/153Un|Qq%s/153UlZ/QqUn'Qd&1UhQl<.UpQn<Qh-\"F%c'TRQs:C>QpJQn<D-%c"L%c1-Qh\|Qh\'RQs:C>Qw"GC|153%pJ'>EX
```
The program, which modifies itself in place, must be saved in a file named `x`. It can be run via the command `tecoc mung x.`. The dot is important; without it, TECO attempted to find a file named `x.tec`. The trailing newline must be present.
The printable ASCII restriction was a bit of a pain for this one, as the language utilizes many unprintable characters. Most of them can be replaced by a two-byte sequence beginning with a caret, but "Escape" (ASCII 27) is the one character that is 'inescapable', so to get it I had to put its ASCII value into a string and exec it. Thus, the 4-byte `EBx<Esc>` exploded into `@^Ux#EBx#27@:^UX##Mx`.
This could be reduced greatly, especially by splitting the program into two parts, storing them as strings and running only if both are present.
] |
[Question]
[
**Closed**. This question needs to be more [focused](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Update the question so it focuses on one problem only by [editing this post](/posts/4651/edit).
Closed 9 years ago.
[Improve this question](/posts/4651/edit)
Your challenge is to write a [Chef](http://www.dangermouse.net/esoteric/chef.html) program that works well as a recipe and also as a program. Its utility as a recipe is strictly required (I don't want a recipe for grapeleaves in chocolate-mustard sauce); its utility as a program is a looser requirement, so that it is enough to print something interesting (the first few integers, for example, or "just another chef", or "just another Chef hacker", or "hello world") or do some helpful calculation (printing the sum of two numbers, for example). Votes should take this into account, and the winner is the program with the most net upvotes after some time.
(Code length is not important here.)
[Answer]
I wrote [this program](https://codegolf.stackexchange.com/a/4850) for [another challenge](https://codegolf.stackexchange.com/questions/4834/lowest-unique-bid-auction), but I decided to try and make it a valid answer for this one too:
```
Shirred Eggs.
This recipe prints the number 2 and, in doing so, yields two delicious
shirred eggs.
Ingredients.
2 eggs
Cooking time: 12 minutes.
Pre-heat oven to 175 degrees Celsius.
Method.
Put eggs into mixing bowl. Pour contents of the mixing bowl into the
baking dish. Shirr the eggs. Bake the eggs until shirred.
Serves 1.
```
As I mentioned in the other answer, it seems pretty hard to write anything in Chef that involves something more complicated than mixing stuff in a bowl and baking it, and still have it work both as a program and as a recipe.
**Edit:** Changed the recipe from fried to [shirred](http://en.wiktionary.org/wiki/shirr) eggs — thanks to Blazer for [the suggestion](https://codegolf.stackexchange.com/questions/4834/lowest-unique-bid-auction/4850#comment10233_4850)! The cooking time and temperature should be considered advisory only; I haven't actually tried the recipe yet myself, so I can't vouch for their accuracy.
] |
[Question]
[
[Code 39](http://en.wikipedia.org/wiki/Code_39), developed in 1974, is one of the most commonly used symbologies, or types, of barcodes, although it is the UPC/EAN system that is most often seen in retail sales. Code 39 barcodes can encode uppercase letters, numbers, and some symbols and are trivial to print from computer software using a special font. This led to their widespread commercial and industrial use (e.g. company ID badges, asset tracking, factory automation).
Create the shortest program or function to read a Code 39 barcode in any orientation from a 512x512 pixel grayscale image; the barcode might not be aligned horizontally or vertically.
* Your program must accept a standard image file format and produce the data encoded in the barcode as its standard output or return value (not including any start/stop character).
* No image contains more than one valid Code 39 barcode, and no barcode encodes a space character (ASCII 32).
* If no valid Code 39 barcode is shown in the image, the program must output a single question mark (`?`).
I have prepared a [JavaScript reference implementation and test suite](https://github.com/plstand/dumb3of9) of images in PNG format, both with valid barcodes and without. The reference implementation, which fails only 3 of 46 test cases in most recent Web browsers, is intended to show one possible decoding algorithm, not to strictly conform to the above specification.
A valid submission passes at least 80% of these tests (37/46) and takes no more than one minute to do so for each image on a reasonably fast CPU (e.g. 2.6 GHz quad-core). My reference implementation passes 93% of tests and processes each image within 10 seconds (on my desktop PC running Google Chrome).
*(This question was [proposed on Meta](https://codegolf.meta.stackexchange.com/questions/336/proposed-questions-sandbox-mk-ii/345#345) on May 28, 2011.)*
[Answer]
## Python, 899 chars
```
import sys,random
raw_input()
X,Y=map(int,raw_input().split())
input()
I=[' x'[v<'~']for v in sys.stdin.read()]
M={196:' ',168:'$',148:'*',388:'.',52:'0',97:'2',49:'4',112:'6',292:'8',73:'B',25:'D',88:'F',268:'H',28:'J',67:'L',19:'N',82:'P',262:'R',22:'T',193:'V',145:'X',208:\
'Z',42:'%',138:'+',133:'-',162:'/',289:'1',352:'3',304:'5',37:'7',100:'9',265:'A',328:'C',280:'E',13:'G',76:'I',259:'K',322:'M',274:'O',7:'Q',70:'S',385:'U',448:'W'\
,400:'Y'}
N=500
for w in' '*30000:
a,b,c,d=eval('random.random(),'*4);A=''.join(I[int((a+(c-a)*i/N)*X)+X*int((b+(d-b)*i/N)*Y)]for i in range(N)).lstrip();T=A.count(' x')+1;K=A.count('x')/T;L=A.count\
(' ')/T;s='';z=c=0
while A:
z*=2;y=A.find(' ')
if y<0:y=len(A)
z+=y>K;A=A[y:]
z*=2;y=A.find('x')
if y<0:y=len(A)
z+=y>L;A=A[y:];c+=2
if c>9:
if z/2in M:s+=M[z/2];z=c=0
else:break
if s and'*'==s[0]and'*'==s[-1]and'*'!=s:print s[1:-1];break
```
This code takes a [pnm format](http://en.wikipedia.org/wiki/Netpbm_format) image as input, so I normally run it like:
```
pngtopnm s01.png | ./barcode.py
```
The code itself just picks lots of random scanlines and tries to match the black and white runs on that scanline to the code39 patterns. It is randomized so it can fail to find barcodes on occasion. (I get about a 20% false negative failure rate on the test images.) When it fails it takes about a minute to run, when it succeeds it often does so much quicker than that. I've never seen a false positive.
] |
[Question]
[
**Closed.** This question is [off-topic](/help/closed-questions). It is not currently accepting answers.
---
Questions without an **objective primary winning criterion** are off-topic, as they make it impossible to indisputably decide which entry should win.
Closed 3 years ago.
[Improve this question](/posts/1213/edit)
I have designed a simple random generator that cycles two numbers in a chaotic way using a multiply and modulus method. It works great for that.
If I were to use it as a cipher generator it would however be vulnerable to a known plaintext attack, given that an attacker can reverse engineer the seed from a series of random numbers in a computationally efficient manner.
To prove the cipher broken **find a legal pair of seed values that generate 7 zeros in a row in the range [0;255], using as little power, CPU-time etc. as possible.**
Here is the random generator written in JavaScript:
```
function seed(state1,state2){
//Constants
var mod1=4294967087
var mul1=65539
var mod2=4294965887
var mul2=65537
function random(limit){
//Cycle each state variable 1 step
state1=(state1*mul1)%mod1
state2=(state2*mul2)%mod2
//Return a random variable
return (state1+state2)%limit
}
//Return the random function
return random
}
//Initiate the random generator using 2 integer values,
//they must be in the ranges [1;4294967086] and [1;4294965886]
random=seed(31337,42)
//Write 7 random values in the range [0;255] to screen
for(a=0;a<7;a++){
document.write(random(256)+"<br>")
}
```
I have made a tool for testing candidate number pairs, it can be found [here](http://ebusiness.hopto.org/testpuzzle.htm).
**For the next 3 days, no spoilers allowed**, an answer must contain only a set of numbers, and it should of course be a different set from those posted by previous solvers. Thereafter you are encouraged to post code and explain your approach.
Edit, quarantine is over:
Answers should contain both a unique set of numbers and explanation and code to document the solving method.
Most elegant solution wins.
For the record:
Writing a program that can find a solution quickly is elegant.
Making a program that utilize the features of a GPU efficiently to do it even faster is elegant.
Doing the job on a piece of "museumware" is elegant.
Finding a solution method that can feasibly be utilized using only pen and paper is very elegant.
Explaining your solution in an instructive and easily understandable manner is elegant.
Using multiple or very expensive computers is inelegant.
[Answer]
# C++, 44014022 / 164607120
It is in C++, uses 1 GB of memory, and took about 45 seconds to find this first pair. I'll update the time once it finds them all.
Code below. It first finds all pairs that generate 4 zeros, then whittles those down by simple trial (see the `check` method). It finds pairs that generate 4 zeros by generating two large arrays, one which contains the first 4 low-order bytes of the state1 generator, and the second which contains the negative of the first 4 low-order bytes of the state2 generator. These arrays are then sorted and searched for a match, which corresponds to the overall generator outputting 4 zeros to start.
The arrays are too big to store in memory, so it does the work in batches sized to just fit in memory.
Looks like the complete run will take ~12 hours.
**Edit**: Improved the code so it only takes ~1 hour to get all possible seeds. Now it generates the tables into 256 different files, one for each first byte of output. We can then process each file independently so we don't have to regenerate data.
**Edit**: Turns out you can generate the 256 subtables individually instead of all at once, so no disk needed. Running time down to ~15 minutes using 256MB.
```
#include <stdio.h>
#include <stdint.h>
#include <algorithm>
using namespace std;
#define M1 65539
#define N1 4294967087
#define M2 65537
#define N2 4294965887
#define MATCHES 7
// M^-1 mod N
#define M1_INV 3027952124
#define M2_INV 1949206866
int npairs = 0;
void check(uint32_t seed1, uint32_t seed2) {
uint32_t s1 = seed1;
uint32_t s2 = seed2;
for (int i = 0; i < MATCHES; i++) {
s1 = (uint64_t)s1 * M1 % N1;
s2 = (uint64_t)s2 * M2 % N2;
if (((s1 + s2) & 0xff) != 0) return;
}
printf("%d %u %u\n", npairs++, seed1, seed2);
}
struct Record {
uint32_t signature; // 2nd through 5th generated bytes
uint32_t seed; // seed that generated them
};
// for sorting Records
bool operator<(const Record &a, const Record &b) {
return a.signature < b.signature;
}
int main(int argc, char *argv[]) {
Record *table1 = (Record*)malloc((N1/256+1)*sizeof(*table1));
Record *table2 = (Record*)malloc((N2/256+1)*sizeof(*table2));
for (int i = 0; i < 256; i++) { // iterate over first byte
printf("first byte %x\n", i);
// generate signatures (bytes 2 through 5) for all states of generator 1
// that generate i as the first byte.
Record *r = table1;
for (uint64_t k = i; k < N1; k += 256) {
uint32_t sig = 0;
uint32_t v = k;
for (int j = 0; j < 4; j++) {
v = (uint64_t)v * M1 % N1;
sig = (sig << 8) + (v & 0xff);
}
r->signature = sig;
r->seed = k;
r++;
}
Record *endtable1 = r;
// generate signatures (bytes 2 through 5) for all states of generator 2
// that generate -i as the first byte.
r = table2;
for (uint64_t k = (-i & 0xff); k < N2; k += 256) {
uint32_t sig = 0;
uint32_t v = k;
for (int j = 0; j < 4; j++) {
v = (uint64_t)v * M2 % N2;
sig = (sig << 8) + (-v & 0xff);
}
r->signature = sig;
r->seed = k;
r++;
}
Record *endtable2 = r;
sort(table1, endtable1);
sort(table2, endtable2);
// iterate through looking for matches
const Record *p1 = table1;
const Record *p2 = table2;
while (p1 < endtable1 && p2 < endtable2) {
if (p1->signature < p2->signature) p1++;
else if (p1->signature > p2->signature) p2++;
else {
check((uint64_t)p1->seed * M1_INV % N1, (uint64_t)p2->seed * M2_INV % N2);
// NOTE: may skip some potential matches, if p1->signature==(p1+1)->signature or p2->signature==(p2+1)->signature
p1++;
}
}
}
}
```
] |
[Question]
[
My third word search related challenge in a row. :)
## Challenge:
#### Brief explanation of what a word search is:
In a [word search](https://en.wikipedia.org/wiki/Word_search) you'll be given a grid of letters and a list of words. The idea is to cross off the words from the list in the grid. The words can be in eight different directions: horizontally from left-to-right or right-to-left; vertically from top-to-bottom or bottom-to-top; diagonally from the topleft-to-bottomright or bottomright-to-topleft; or anti-diagonally from the topright-to-bottomleft or bottomleft-to-topright.
#### Actual challenge:
Given a list of coordinates indicating the crossed out words within a grid (in any reasonable format*†*), output how many line-islands there are.
We've had challenges involving finding the amount of islands in a matrix. But in this case it's different: just looking at the grid, words could be right next to each other, but would still be two separated line-islands. E.g. In the following partially solved word search, we have four separated line-islands, even though the letters of the words are right next to each other.
[](https://i.stack.imgur.com/Ixc5v.png)
This partially solved word search above would result in an output of `4`.
If 'word' `FG` was `FGH` like this:
[](https://i.stack.imgur.com/EzHDe.png)
The output would have been `3` instead, because the `FGH`+`NKH` now form a single connected line-island.
In this challenge we'll only be taking the coordinates of the words in a grid as input, and output the amount of line-islands.
## Challenge rules:
* *†* You're allowed to take the input in any reasonable format. It could be pair of coordinates per word to indicate their start/end positions (e.g. `[[[0,0],[0,2]],[[1,1],[1,3]],[[3,1],[1,3]],[[3,2],[2,3]]]` for the second example above); it could be a full list of coordinates per word (e.g. `[[[0,0],[0,1],[0,2]],[[1,1],[1,2],[1,3]],[[3,1],[2,2],[1,3]],[[3,2],[2,3]]]`); a list of bit-mask matrices per word (e.g. `[[[1,1,1,0],[0,0,0,0],[0,0,0,0],[0,0,0,0]],[[0,0,0,0],[0,1,1,1],[0,0,0,0],[0,0,0,0]],[[0,0,0,0],[0,0,0,1],[0,0,1,0],[0,1,0,0]],[[0,0,0,0],[0,0,0,0],[0,0,0,1],[0,0,1,0]]]`); etc. If you're unsure if a possible input-format is valid, leave a comment down below.
* All 'words' are guaranteed to have at least two letters.
* You can assume the input won't be empty.
* You can optionally take the dimensions of the grid as additional input.
* Note that coordinates of 'words' are not guaranteed to be in the same positions to still form a single line-island! E.g. this grid would result in `1` because the lines cross, but neither 'word' share the same letter-positions:
[](https://i.stack.imgur.com/MM1au.png)
## General rules:
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so the shortest answer in bytes wins.
Don't let code-golf languages discourage you from posting answers with non-codegolfing languages. Try to come up with an as short as possible answer for 'any' programming language.
* [Standard rules apply](https://codegolf.meta.stackexchange.com/questions/2419/default-for-code-golf-program-function-or-snippet/2422#2422) for your answer with [default I/O rules](https://codegolf.meta.stackexchange.com/questions/2447/default-for-code-golf-input-output-methods/), so you are allowed to use STDIN/STDOUT, functions/method with the proper parameters and return-type, full programs. Your call.
* [Default Loopholes](https://codegolf.meta.stackexchange.com/questions/1061/loopholes-that-are-forbidden-by-default) are forbidden.
* If possible, please add a link with a test for your code (e.g. [TIO](https://tio.run/#)).
* Also, adding an explanation for your answer is highly recommended.
## Test cases:
[](https://i.stack.imgur.com/Ixc5v.png)
* Input as start/ending coordinates of the 'words': `[[[0,0],[0,2]],[[1,1],[1,2]],[[3,1],[1,3]],[[3,2],[2,3]]]`
* Input as coordinates of the complete 'words': `[[[0,0],[0,1],[0,2]],[[1,1],[1,2]],[[3,1],[2,2],[1,3]],[[3,2],[2,3]]]`
* Input as bit-mask matrices of the 'words': `[[[1,1,1,0],[0,0,0,0],[0,0,0,0],[0,0,0,0]],[[0,0,0,0],[0,1,1,0],[0,0,0,0],[0,0,0,0]],[[0,0,0,0],[0,0,0,1],[0,0,1,0],[0,1,0,0]],[[0,0,0,0],[0,0,0,0],[0,0,0,1],[0,0,1,0]]]`
**Output: `4`**
---
[](https://i.stack.imgur.com/EzHDe.png)
* Input as start/ending coordinates of the 'words': `[[[0,0],[0,2]],[[1,1],[1,3]],[[3,1],[1,3]],[[3,2],[2,3]]]`
* Input as coordinates of the complete 'words': `[[[0,0],[0,1],[0,2]],[[1,1],[1,2],[1,3]],[[3,1],[2,2],[1,3]],[[3,2],[2,3]]]`
* Input as bit-mask matrices of the 'words': `[[[1,1,1,0],[0,0,0,0],[0,0,0,0],[0,0,0,0]],[[0,0,0,0],[0,1,1,1],[0,0,0,0],[0,0,0,0]],[[0,0,0,0],[0,0,0,1],[0,0,1,0],[0,1,0,0]],[[0,0,0,0],[0,0,0,0],[0,0,0,1],[0,0,1,0]]]`
**Output: `3`**
---
[](https://i.stack.imgur.com/MM1au.png)
* Input as start/ending coordinates of the 'words': `[[[0,0],[1,1]],[[0,1],[1,0]]]`
* Input as coordinates of the complete 'words': `[[[0,0],[1,1]],[[0,1],[1,0]]]`
* Input as bit-mask matrices of the 'words': `[[[1,0],[0,1]],[[0,1],[1,0]]]`
**Output: `1`**
---
[](https://i.stack.imgur.com/mrZ3j.png)
* Input as start/ending coordinates of the 'words': `[[[1,9],[8,9]],[[8,6],[1,6]],[[1,4],[4,7]],[[9,0],[0,9]],[[1,0],[6,0]],[[6,1],[3,4]],[[9,4],[9,9]],[[0,1],[0,8]],[[9,3],[1,3]],[[0,0],[9,9]]]`
* Input as coordinates of the complete 'words': `[[[1,9],[2,9],[3,9],[4,9],[5,9],[6,9],[7,9],[8,9]],[[8,6],[7,6],[6,6],[5,6],[4,6],[3,6],[2,6],[1,6]],[[1,4],[2,5],[3,6],[4,7]],[[9,0],[8,1],[7,2],[6,3],[5,4],[4,5],[3,6],[2,7],[1,8],[0,9]],[[1,0],[2,0],[3,0],[4,0],[5,0],[6,0]],[[6,1],[5,2],[4,3],[3,4]],[[9,4],[9,5],[9,6],[9,7],[9,8],[9,9]],[[0,1],[0,2],[0,3],[0,4],[0,5],[0,6],[0,7],[0,8]],[[9,3],[8,3],[7,3],[6,3],[5,3],[4,3],[3,3],[2,3],[1,3]],[[0,0],[1,1],[2,2],[3,3],[4,4],[5,5],[6,6],[7,7],[8,8],[9,9]]]`
* Input as bit-mask matrices of the 'words': [pastebin](https://pastebin.com/MA6rJqsT)
**Output: `4`**
---
[](https://i.stack.imgur.com/qg3N9.png)
* Input as start/ending coordinates of the 'words': `[[[8,6],[1,6]],[[1,4],[4,7]],[[9,0],[0,9]],[[6,1],[3,4]],[[9,4],[9,9]],[[9,3],[1,3]],[[0,0],[9,9]]]`
* Input as coordinates of the complete 'words': `[[[8,6],[7,6],[6,6],[5,6],[4,6],[3,6],[2,6],[1,6]],[[1,4],[2,5],[3,6],[4,7]],[[9,0],[8,1],[7,2],[6,3],[5,4],[4,5],[3,6],[2,7],[1,8],[0,9]],[[6,1],[5,2],[4,3],[3,4]],[[9,4],[9,5],[9,6],[9,7],[9,8],[9,9]],[[9,3],[8,3],[7,3],[6,3],[5,3],[4,3],[3,3],[2,3],[1,3]],[[0,0],[1,1],[2,2],[3,3],[4,4],[5,5],[6,6],[7,7],[8,8],[9,9]]]`
* Input as bit-mask matrices of the 'words': [pastebin](https://pastebin.com/JCAP7Jmj)
**Output: `1`**
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), ~~22~~ 20 [bytes](https://github.com/DennisMitchell/jelly/wiki/Code-page)
```
żSH$ƝẎ)ṭfƇ@ẎQʋ€ÐL`QL
```
A monadic Link that accepts a list of lists of pairs of integers - the full list of coordinates for each word - and yields the island count.
**[Try it online!](https://tio.run/##y0rNyan8///onmAPlWNzH@7q03y4c23asXYHIDPwVPejpjWHJ/gkBPr8//8/OjraQMcgVifaUMcwFkhFG@kYASljHWMwzwAoCpIzgMoZg@WMYmNjAQ "Jelly – Try It Online")** (Two islands each being two words crossing at cell corners, where equal-island words are non-adjacent in the input list.)
Or see the [test-suite](https://tio.run/##zZE9TgMxEIV7zkGD5MK7Y4/tjpIiTUQZrUQDBcoFaGlSICEuwA3gACC6iBTcIlzE2F@c7HYgUcAWbz1/783P9eVyeZPz@9v52fHmcft6f7J9eb7arE7Lc/5x93n7tH6YXcxneb0q75wX5bPGDqZgB/ZD@S06rK5ZgtUXq/qk@Xp8xRqOzLc008Ifk9XyGraNxu7DnUnkVxTQgR5UMICxYKWIRvEpcSVXqVM4FD5FRlvvDp8/xJ0JRBLNRZoKdK6l88royPITxgBjZCep8VoilixLhaXawmTJUtg97A52Kew79aqSUEmoJFQSKqmpjHeoKKADPahgAGPjFaYSppLJVDLpQdqdxtuNp9pfVVqFo9ofNh7Qi2Ofu2P@n9P8dul/ssLhCw "Jelly – Try It Online").
### How?
*Needs updating*:
```
ṭfƇ@ẎṢQ - Link 1, add crossing words: Coordinates, (all) Word Coordinates
@ - with swapped arguments:
Ƈ - filter keep (those Word Coordinate lists) for which:
f - filter keep (i.e. contain some of the same entries)
ṭ - tack to Coordinates
Ẏ - tighten
Ṣ - sort
Q - deduplicate
żSH$ƝẎ)ç€ÐL`QL - Main Link: Word Coordinates
) - for each list in Word Coordinates:
$Ɲ - for neighbours:
S - sum (vectorises)
H - halve
ż - Word Coordinates zip-with those "intermediate coordinates"
Ẏ - tighten
` - use as both arguments of:
ÐL - loop until no change with:
ç€ - call Link 1 for each
Q - deduplicate
L - length
```
[Answer]
# Python3, 560 bytes:
```
lambda w:len({str(i[0])for i in g(w)})
S=lambda a:[(t:=(a[1][0]-a[0][0])/([1,(k:=a[1][1]-a[0][1])][k!=0])*(k>0)),[a[0][1],t*-1*a[0][1]+a[0][0]][k!=0]]
M=lambda j,k:[(x:=(k[1]-j[1])/(j[0]-k[0])),j[0]*x+j[1]][::-1]
N=lambda s,p:min(t:=[s[0][0],s[1][0]])<=p[0]<=max(t)and min(t:=[s[0][1],s[1][1]])<=p[1]<=max(t)
V=lambda a,b:(j:=S(a))[0]!=(k:=S(b))[0]and N(a,m:=M(j,k))and N(b,m)
def g(w):
Q,S=[[i]for i in w],[]
while Q:
if(v:=Q.pop(0))[-1]not in S:
if[]==(j:=[i for i in w if i not in S and V(v[-1],i)]):yield v
else:Q=[v+[i]for i in j]+Q
S+=v[-1:]
```
[Try it online!](https://tio.run/##nZFNbtswEIX3OgWzG1p0I1qBYxNhb5AAgoBsWC5kWGqoPwuWYDsoenZ3RqKdtAXSIhtSo/fNe6NR9zq87Np41e3Phf52rrNms83YUdV5Cz/6YQ/ORJYXuz1zzLXsOxz5Tx6k2oOZMjAoDZmRFsF5hgc13IKRAiqlR0F6QVpuTXWjEZhB9TXiXBgviGE2lzNfhN7GwzZ4vOSVosLEEyZW5FqS5S2UFF1RLhf0PDuFpFij1Fza4OnS3YtONa6liU0/RYh@mtzyB93h/aCb7AQDz9ot@w2VHpUelVc0eL5uQ2wUlEqnkHGOTTeaVpDCZqzI8gky0Sj9CPghnE9vNqLhwTYvxuWqgCUi1cY4e1360QpjA3Z8cXXOEiSYK@CgdPKl23WAWzT4le1uIDYlGXVjtaZRjGNvPvgeny4ko/hnOFC3cNxy9eryessO5JDXfa4SbQ7h@0lKGyakpqGmNmXP3d61AxRgjIkErhPPhcULfz@64jlVsa9iXy3wWlCFvyz4p0f8CQ/qJS7yXdFfnBRrVFZ4ErcSy5Fb@uQ7vO7E/Vit/VRrr1G1JEeslqN/jPxEUt/ak1N2JFZei9/NP005kn/M9f@TfJT9Udr5Fw)
[Answer]
# [Wolfram Language (Mathematica)](https://www.wolfram.com/wolframscript/), 90 bytes
```
Length@ConnectedComponents@Graph[#->If[#⋂#2=={},##]&@@@Tuples[Total/@#~Tuples~2&/@#,2]]&
```
[Try it online!](https://tio.run/##zVM9a8MwFNz9NwyZVCxbsmwNLoIMpdChQ7aQwaRKHUjsEKuTcYau/Zf9I650UW2PgQ4phAvv4@6e3sPH0lT6WJr9thx2xfCi63dTqWVT13pr9NuyOZ6aWtemVU/n8lStw4fH5906/P76DJOi6HoShpuFUmr1cTrodr1qTHmIVHi5xpdkYQOSbDaLwejWbMtWt0UXBF3XUUJ7YjEGJr3962JEsY8YosRGLsd8LkHORj25QWfOvF3N8V2deh061mMiwXDIgByYAgUwA@YWnUZOBHICdYFeAZ6AhoCegI/w03Pk0rHOSYaKxHQ5psowu7CzO0WOrnSmmEExx1ak16WoUHRRMCjYFEoUXQLqKdQ51JlVv7o7FwkXCRcJFwkX6V2mSzhkQA5MgQKYAXOvy/Aqhlex2avYbAbmLzVdb7rV712ZZ3Cw03HjGfzyaU5/zf9zm79u/R47DAL720Vq/LKj6PW8r83wAw "Wolfram Language (Mathematica) – Try It Online")
A simple set intersection between the lists of coordinates would detect almost all the cases except the 'phantom intersection' of two diagonal 'words'.
In this special case, these phantom intersecting diagonals, have both 2 coordinates that add up to a same one.
```
+---------+---------+
|A |B |
| x y | x+1 y |
| | |
+---------X---------+ A coords. B coords.
|B |A | (x,y) + (x+1,y+1) = (x,y+1) + (x+1,y)
| x y+1 | x+1 y+1 |
| | |
+---------+---------+
```
Unfortunately a test for this would not detect the standard intersection of two words that actually have one common coordinate. As such my first implementation combined two test:
* the intersection between the plain lists of coordinates `#`
* the intersection between the lists of the **sums of consecutive coordinates** `Partition[#,2,1]` (this also assumed the lists would always be in order).
But then I thought why not **sum every pair of coordinates** (multisets) of a 'word'?
Also pushed by the fact that `Tuples[#,2]` is shorter than `Partition[#,2,1]`
## Technicalities
The only doubt: can there be false positives?
That is, can two 'words' that do not share any coordinate be mapped into 'words' that do share some coordinates?
To sum all the coordinates in a 'word' with themselves is essentially a x2 scaling done in a redundant fashion.
So, for each mapped coordinate of a 'word' \$(x\_i+x\_j,y\_i+y\_j)\$ we can infer its preimage: a pair of coordinates of 'word' that yield the mapped one. Hence if two 'words' share a mapped coordinate they also have to share the relative pair of 'core coordinates'.
This pair of 'core coordinates' (`P`,`b`) are the two coordinates around the possibly 'phantom point' (`@`) \$(\frac{x\_i+x\_j}{2},\frac{y\_i+y\_j}{2})\$
```
+---------+---------+ +---------+---------+ +---------+---------+ +---------+---------+ +---------+---------+
|BBBBBBBBB| | |PPPPPPPPP| | | | | |PPPPPPPPP| | | |PPPPPPPPP|
|BBBB@BBBB| | |PPPPPPPPP| | | | | |PPPPPPPPP| | | |PPPPPPPPP|
|BBBBBBBBB| | |PPPPPPPPP| | | | | |PPPPPPPPP| | | |PPPPPPPPP|
+---------+---------+ , +----@----+---------+ , +---------+---------+ , +---------@---------+ OR +---------@---------+
| | | |bbbbbbbbb| | |PPPPPPPPP|bbbbbbbbb| | |bbbbbbbbb| |bbbbbbbbb| |
| | | |bbbbbbbbb| | |PPPPPPPPP@bbbbbbbbb| | |bbbbbbbbb| |bbbbbbbbb| |
| | | |bbbbbbbbb| | |PPPPPPPPP|bbbbbbbbb| | |bbbbbbbbb| |bbbbbbbbb| |
+---------+---------+ +---------+---------+ +---------+---------+ +---------+---------+ +---------+---------+
```
] |
[Question]
[
If you have read in your childhood a Geronimo Stilton's book, I am sure that you remember the style of the text, sometimes the words were decorated for making the act of reading more funny for kids: [example](https://www.google.com/search?q=geronimo%20stilton%20texto&tbm=isch&ved=2ahUKEwiSzoTxwdXwAhWJ5RoKHa0jAc0Q2-cCegQIABAA&oq=geronimo%20stilton%20texto&gs_lcp=CgNpbWcQAzoCCAA6BAgAEB46BggAEAgQHjoECAAQE1CkNFifPWCPP2gAcAB4AIABWYgB7QOSAQE2mAEAoAEBqgELZ3dzLXdpei1pbWfAAQE&sclient=img&ei=c-WkYNLIDInLa63HhOgM&bih=774&biw=1190&rlz=1C1CHBF_esES920ES920#imgrc=c_67TO5E7NrLLM).
But when you are an adult you don't have that little entertainment in your readings... why?
In a nostalgic attack I have decided to make an algorithm to create that output with every text in the world.
It's not very similar, but it's curious.
## Idea:
Make a program that with an input like this:
```
It was in the morning of June 21, and I had just set
paw in the office. Right away I could tell it wasn't
going to be a good day. My staff was running
around like a pack of rats in a maze. And everyone
was complaining about something.
"Geronimo, the air-conditioner's broken!"
yelled my secretary, Mousella MacMouser.
"Geronimo, we are run out of coffee!" shrieked
Blasco Tabasco, one of my designers.
"Geronimo, the computers are all down!"
cried my proofreader. Mickey Misprint.
```
Create an output like this:
[](https://i.stack.imgur.com/ziGNU.png)
or this:
[](https://i.stack.imgur.com/Wivc4.png)
(These outputs are images because there are two ways to create the output, show it in your program some way or create an output HTML like mine.) This is my raw output:
```
<font face="Verdana">It was in the morning of June 21, and I had just set </br>
paw in the <b><font face="Comic Sans MS" size="5" style="color:rgb(111,229,136);">office</font></b>. Right away I could tell it wasn't </br>
going to be a good day. My staff was <b><font face="Comic Sans MS" size="5" style="color:rgb(77,170,241);">running</font></b> </br>
around like a pack of rats in a maze. And everyone </br>
was complaining about something. </br>
"Geronimo, the air-conditioner's broken!" </br>
<b><font face="Comic Sans MS" size="5" style="color:rgb(174,152,239);">yelled</font></b> my secretary, Mousella MacMouser. </br>
"Geronimo, we are run out of coffee!" shrieked </br>
Blasco Tabasco, one of my <b><font face="Comic Sans MS" size="5" style="color:rgb(101,139,153);">designers</font></b>. </br>
"Geronimo, the computers are all down!" </br>
cried my <u><font face="Comic Sans MS" size="5" style="color:rgb(70,164,71);">proofreader</font></u>. Mickey Misprint. </br>
</font>
```
## Algorithm:
I have made an example of the algorithm (not golfed) in Java: [Here is it](https://tio.run/##xVZRk9o2EH6/X7HVQ2LXHDnIkM7dYTJNHzLpDC8l0z4AD7Isgw4jMZJ8Lrnw268rgY1d4JJpO1PPzdksu/t9@@1qzQN9pNcP6er5meXUGPjItZJireDpCvDaFEkuGBhLLd4elUhhTYUMJlYLuZjOgeqFCfe@7trbQUhhBc0/8z9tTD5ZKKlBG9glh7XS0rmoDH4tJId@rwNUpvAJljSFh8JYMNzOJIGozlpdZEPLKo/KMsF4F34Ti6UFWtItpmCqyFOwPM9BeFT5@lKqhXIsrIKEA4WFUimkdNuF8dZVm2Wesy6kI3shBdWqQOa5WLkUG8pWripNrS@WolJfkODP6MIfud4qyS8kclBMrTc5SutY0UQVKINac7vEz90LYTNSdavjJaFCXzMlU9QesfRrA4lWKy5/mJELGbaoFMeWYs2caW6p3nZgrAqDdgpjyvyz/h4CJeJr7hQDRx6FYNgizhEczFILvuLphTQfcPKYgs80cfcOIHkXj6xSbsQCSzHfK4FTsbAY4MlQnINUlS8IwJCYr3@jlco0pylWC2PBVnyLN7PBcbZdcv/3Ac@ErMZ7mClpIaOMxzPyO9cplXRGRicxeFgMl5ZLxk3cOCBds8mFDRzD8BiDsGA2nKHTH0qncYCGMBhTu@xqPC5qHYQ/3oZR76YdggcAIXTcMGdKBz4bGsEMaw7dnMuFXaItihonuEW4RGgT1yFTM6/YQpNsE6Z0MOXQR9YQ5QmEJ5wFB77DRqlnHN118Iyi@7Nf1w2JYg89LecRkjx13vHccAdduR1IBuHo7cvQTVGb17fa1HsXRoPzobXQLOdUxv6/y1OTQ5HPBjql9wATXM38LO7bqBe@BIurOBW4RKlbFxC38sW99yQhd0HL1n9PCnJHBAm/2QNfyfQGezAkURMnIqPWgflFrfHFMqHSwHjiVoX44swD92i3uXtmKlf6Ti@SgETn6uwPBmFEOv/4y/DeHddoT7nnKL9xDEfDNyfUK6/@S8P19C8H9Oryp0YSZJnoES6NY4ajb9vPV0MakzTZGsvXXdzTXb/gchnUEYfe7q7OvP/b4@oH9TBKZfvg1o6Sl84Np@uJYBfc3@50NQm3M4TfGfVpRMPJ0viwtbjiMZn3XHDrDCYIp2Le1tFtluG7AXz9CgEb3d7Aq1fAhrc/hc7CRr1@/8xRP3B1UxsHbEl16GeGtVNfaHGC747V/YXW7c5U3Cr2uofljpwI19f/S839eavk6Gj/L6uvsvbm@/JNkRg/KcFR@1qTTluhI6Pa1lhD@Nul0LICqEZ4d/X8/Bc)
This is the list of steps that you have to follow starting whit the base input:
1. Start catching a random word in position 5-20(words)
2. If the word is less or equals to 3 char long (e.g. `her`, `a`) catch the next word until you find someone whit more than 3 char
3. "Clean the word", the transformed word cant contain characters like `"` or `.`. The modified word has to starts and end whit [A-Z][a-z] and only whit that characters so... clean it if you need is the 3th step
```
Examples of this step:
if you word is | word cleaned
------------------|----------------
"Geronimo, | Geronimo
final. | final
air-conditioner | air-conditioner (Don't remove special characters inside the word)
```
4. Put it randomly (1/3 cases) in **bold**, *cursive* or underlined (Only one at the same time for word)
5. Give the word a bigger size than the rest of the text (how much big is your election)
6. Give the word a random color (Try to make this in the widest range of colors that you can, in my code creates an RGB with Java random function in every color that goes from 0 to 255)
7. Give the word any font... (What you want, doesn't matter what you use but must be different to the text font)
8. From this word repeat the 1st step for grab a new one random word next to this
Example of algorithm:
```
In step one by a random decision between 5 and 20 you have to start in word 7 for example:
It was in the morning of *June* 21, and I had just set
paw in the office.
On time that you have modified that word you start again the random function and
you add the result to your actual position for get the next word... the result
of the random function this time has been 8:
It was in the morning of *June* 21, and I had just set
paw *in* the office.
But that word is 2 char long and the next one too so we take the word "office"
It was in the morning of *June* 21, and I had just set
paw in the *office.*
Office has a point at the end, lets clean it:
It was in the morning of *June* 21, and I had just set
paw in the *office*.
And the last step is modify this last word
```
Rules
* As I have said, **the output can be show in your program** (or directly in HTML if you use JavaScript or something like that) **or outputs an HTML text whit all the properties in it**.
* The **structure of the HTML can be as you want, as long as when you execute it the result should follow the rules**. Basically, you don't have to make it like my example output.
* The **base font and size can be what you want**, I have used Verdana in my example because I think that the output is more... "beautiful"? and my code is not golfed.
* If you can, put a picture to the executed HTML in your solution please.
* In reference to the randomness, the only thing that is relevant is that **the output text has different colors, styles and words every time you run the program**, if there some options are more probable (for example red is more probable than green as a color) that doesn't matter.
* And in reference to the randomness of the colors, **it's not necessary that all colors are contemplated in the output, try to put the most colors you can**... I know that this is not very mathematically precise because is a problem to talk about colors when there are so much ways to create them (RGB, hexadecimal, HSV...) so I'm going to try to put a "minimal" rule:
* **Lets say that the "extreme" colors must have non 0 probability**, for example in RGB I mean that this colors are mandatory: `0,0,0` `255,255,255` `255,0,0` `0,255,0` `0,0,255` `255,0,255` `0,255,255` `255,255,0` but if you want you can use too the colors in between (That is the principal idea)
And **if for some reason you cant use that rule of extreme colors have in mind that at least the output must be 8 different colors**.
* This is code golf, so the shortest code wins.
[Answer]
# [JavaScript (Node.js)](https://nodejs.org), ~~246 244~~ 232 bytes
```
f=(i,j=p=0,r=_=>Math.random()*3|0,q=_=>p+=4+r()*5,x=q())=>i.replace(/[-'\w]+/g,m=>j++==p?(m[3]?[q(),`<${s="bis"[r()]} style="font:2em monospace;color:rgb(${[r()*85,r()*85,r()*85]})">${m}</${s}>`]:[++p,m])[1]:m).replace(/\n/g,"<br>")
```
[Try it online!](https://tio.run/##ZZJPb5tAEMXvfIoJihQIhPxrpMrJOmovVSr5UvXmoHqBAa/N7pDdJQ51/dndgaqqop4GZt@@95vRbuSrdKVVnb8wVOHxWItIpRvRiavUih9ivpB@nVlpKtJRfH776yp9GdtdIj4kljt36Zt4ieJYzFVmsWtlidHl8uLseZcnl02qxXyTJEJ0j5Fe3uaPS9amq4fTvRNhoVy4ZI/8AM4PLYqwJuNnN6hBkyHXsdd9SS3ZmW2K6HQ/is8/3qXvSn6Iw/npXh8eLtn1MF/ls2WSdKnO4@V1PtPxP6xnw0ThQ2HnYXx8lRZKELB68rCTDpQBv0ZOtkaZBqiGr71BuLlOgaeHJ1jLCja98@DQB53c/b1Bda1KzOCbatYe5E4OLC6pbyvw2LagJn9z5oOGRmdPUCBIaIgqqOSQwWLgBci6njhsb0aAQFrqObdV21HMu9iOTFb6CVWClj859BNL8BXtQAaD8XpJmqdV0wyyoJ5xSaNf838WhF/QklGa0olcKntRkqmUV3zdnjkoLG3RnITBwORYgWYyLC16aYcUFtQ77ktYyHL6tu8sd@xocRwAxlymLXk3iCchuLVVuMUq@NzycyP4LouxpsC5o5BzKnSqYQr3H@Y4Uu/5ZLKXvNKKdiMkv9s/jJ0lqi3KiolgocotDlxcZ5Xx2eo@CHhKRy1mLTVRHZVxfH/8DQ "JavaScript (Node.js) – Try It Online")
*Saved ~~2~~ 8 bytes thanks to @ophact!*
*Saved 6 bytes thanks to @EliteDaMyth!*
---
Returns the resulting text with HTML-formatting applied.
(Ab)uses a RegExp-replacer to modify the picked words. If anyone is interested, I'd be happy to add an explanation, if requested.
---
```
f=(i,j=p=0,r=_=>Math.random()*3|0,q=_=>p+=4+r()*5,x=q())=>i.replace(/[-'\w]+/g,m=>j++==p?(m[3]?[q(),`<${s="bis"[r()]} style="font:2em monospace;color:rgb(${[r()*85,r()*85,r()*85]})">${m}</${s}>`]:[++p,m])[1]:m).replace(/\n/g,"<br>")
var c = `It was in the morning of June 21, and I had just set
paw in the office. Right away I could tell it wasn't
going to be a good day. My staff was running
around like a pack of rats in a maze. And everyone
was complaining about something.
"Geronimo, the air-conditioner's broken!"
yelled my secretary, Mousella MacMouser.
"Geronimo, we are run out of coffee!" shrieked
Blasco Tabasco, one of my designers.
"Geronimo, the computers are all down!"
cried my proofreader. Mickey Misprint.`;
document.write(f(c));
```
[Answer]
# [JavaScript (Node.js)](https://nodejs.org), ~~459...~~ 375 bytes
```
m=>`<p>${(g=(t,M=Math.random,c=_=>M()*255|0,o=c(),p=c(),q=c(),y='biu'[M()*3|0],x=(N,F)=>N.replace(/[a-zA-Z]|(?<=[a-zA-Z]).(?=[a-zA-Z])/g,F),T=t.length<20,z=_=>T?0:x(t[B=4+M()*15|0],G=>G)[3]?B:z())=>T?t:(t[C=z()]=x(t[C],Y=>`<${y} style=font-size:20;font-family:sans-serif;color:rgb(${[o,p,q]})>${Y}</${y}>`))&&t.slice(0,20).concat(g(t.slice(20))))(m.split(/\s/)).join` `}</p>`
```
[Try it online!](https://tio.run/##ZVNRT9swEH7vrzgQos7mpqWMl1K3AqRVTCoPEy@sq1Y3cVLTxBdsh5ICv707Z0LTtDzYuct33/fdOX6Uz9IlVle@ZzBVh0wcSjFZjavJySvLBfN8LubSb2IrTYolT8QvMZmz6NPw4uJtwFEkLOJVuz61ayO6a113FwFz/jZY8hfB7vjXSEzuYquqQiaK9Reyt7/q/Vi@selYfARRzKZ/g35ORfxe@LhQJveb8XDA90H8fjoYvTC/uBZfPgeRs4ugMhOTWbQ4X06vR3sWRQHmR4S6ERQuRSi4WfKH0NrJa/MOzjeFEhka33N6r0bDwWUbZLLURTNy0rieU1ZnlwkWaEc2X7OT1wXyij8t3yOazsP7uB@oJqsoOj31sSs0tTbgw0EUJ2gS6VnOPtKUpIeVsasK7Vn/p@tHUfyI2qxgRUTVZHWgIoeFigvMWcZWtx520oE24DcKSrRGmxwwg2@1UTA840AnArewkSk81s6DU75Tyd1HBWYZKcfwXecbD3InGwInWBcpeFUUoFt@0/WdHAOzR1grkJAjppDKJoZ5Q2OSWdb6sLUJBjrSYk26hd4GcCWTbfBkpW@tSijlnkSvCKKelW3QqE4oT7Cks9dtD3KNNdnFUvkNxXHneKYsGl0ib51LbXs0jFR7TeW262BtcavM0XGnIecqhZKcqcQqL23DYY61o7yEuUzad/sP5Y4YrQoNQNAltwnNRqmjY3Abq9VWpZ3rgm4Bwr1ch50D6QYg6aTK6ZxcuP9shpZqT19aekkjTXEXTNJ1@uOxsoiZVTIlRzDXyVY1tLnKauNj@m0OvwE "JavaScript (Node.js) – Try It Online")
Wow. Just wow. I'm probably missing a really obvious golf here. This is probably the longest program I have ever written, after "Help me count the omer".
## How does this work?
Wraps an immediate invocation of `g`, a recursive function, inside a `p` tag.
In `g`, we initialize multiple arguments: `t`, which is an array of words, `M`, the built-in random function, and then `c` which returns a random integer from 0 to 255. This is followed by three invocations used as the color of the word (each call to `g` only replaces one word). We also set the "effect" used on the modified word. Next, the function `x` is where the magic happens: takes a word and a callback and replaces all alphabetical letters and special characters sandwiched between alphabetical letters with a call to the callback. I'm not a regular expressions expert, but luckily I knew enough about lookbehinds and lookaheads to implement the `replace`. This saved 47 bytes because before I was using a lengthy `test` condition.
We also create `z` which finds a random number whose corresponding word has at least 4 characters.
Function body: if the length of `t` is less than 20, return `t` unchanged, otherwise set `t[C=z()]` (the random word) to a call to `x` with that word and a special HTML generator as a callback. We also use an `&&` so that rather than returning an assignment, we return a concatenation of the new `t` and a recursive call with `t.slice(20)`. Note that using spread operators saves no bytes.
`g` is then invoked with `m.split(/\s/)` and joined with a space.
] |
[Question]
[
The program should start out with 2 separate files, here named "a" and "b". "a" and "b" should be what I am calling inverse quines: "a", when run, should output "b"'s source code, and "b", when run, should output "a"'s source code, for example:
```
./a
#source code of b, optionally followed by newlines
./b
#source code of a, optionally followed by newlines
```
If the outputs of "a" and "b" are then appended to the same file, here called "c", such as this:
```
touch c
./a >> c
./b >> c
```
The resulting file, "c", when run, should output the code of "a", followed by a newline, followed by the source code of "b" and a newline. The full running of these files should go as follows:
```
touch c
./a >> c
./b >> c
./c
#source code of a \n
#source code of b \n
```
Any coding languages can be used, and as this is code golf, the source code should be as small as possible.
There are no limits on what the source code of "a" and "b" can be, and newlines can be placed freely at the end of code outputs, such that the output ends in a single or a string of newlines.
[Answer]
# Bash, 63 37 bytes
## a
```
t=;x(){ cat $2 $1;};x b \
```
## b
```
${t-cat} a
```
-26 bytes thanks to Nahuel Fouilleul
[Try it online!](https://tio.run/##dc@9CoMwEAfw/Z7ihkB0cGhXrdCChUIfwSV3plgIhmJEW/HZbVSkDnX93/3ug1RdjiMrh0kir7d7dpaYogJ3irsg7HGqiCOKQzzEHRLmMDcBbMhlIgSid5FPB6/ndOlRHqXIAJpLizLrNDdO@zhgWzldOaxL25gC9atRBimUQP4mP2QRQubVimgHqRXRH8R7CB/WGNvqAun928ubEfXzoyW0jBFPf4zjFw "Bash – Try It Online")
## quick explanation
There are two key tricks:
* We define our own version of `cat` called `x` which swaps its arguments, when there are 2 arguments given. It will have only 1 argument when `a` is run, but 2 arguments when `c` is run.
* `b` uses bash default arguments to accomplish what it needs. When `t` is undefined, as it will be when `b` is run alone, it becomes `cat a`. When t is defined, it just returns `a`, becoming the second argument to `a` command `x b a`.
[Answer]
# [05AB1E](https://github.com/Adriandmen/05AB1E/wiki/Commands), 39 (20+19) [bytes](https://github.com/Adriandmen/05AB1E/wiki/Codepage)
## Program a:
```
"34çìD«r»¨"34çìD«r»¨
```
[Try it online.](https://tio.run/##yy9OTMpM/f9fydjk8PLDa1wOrS46tPvQCjTu//8A)
## Program b:
```
"34çìD«r»¨"34çìD«r»
```
[Try it online.](https://tio.run/##yy9OTMpM/f9fydjk8PLDa1wOrS46tPvQChTu//8A)
## Program c (concatenation of a+b):
```
"34çìD«r»¨"34çìD«r»¨"34çìD«r»¨"34çìD«r»
```
[Try it online](https://tio.run/##yy9OTMpM/f9fydjk8PLDa1wOrS46tPvQChK4//8DAA) or [try it online as pure quine](https://tio.run/##yy9OTMpM/f9fydjk8PLDa1wOrS46tPvQCjQuFz5prv//AQ).
**Explanation:**
*Program a:*
```
"34çìD«r»¨" # Push string '34çìD«r»¨'
34 # Push 34
ç # Convert it to a character: '"'
ì # Prepend it in front of the string: '"34çìD«r»¨'
D # Duplicate it
« # Merge the copy to itself: '"34çìD«r»¨"34çìD«r»¨'
r # Reverse the items on the stack
# (no-op, since there is just a single item)
» # Join all items on the stack by newlines
# (no-op, since there is just a single item)
¨ # Remove the last character: '"34çìD«r»¨"34çìD«r»'
# (after which the result is output implicitly)
```
*Program b:*
The same as program a, but without the trailing `¨`, so it'll output `"34çìD«r»¨"34çìD«r»¨` (being program a) instead.
*Program c:*
```
"34çìD«r»¨"34çìD«r»¨ # It starts the same as program a
"34çìD«r»¨" # Push string '34çìD«r»¨'
# STACK: ['"34çìD«r»¨"34çìD«r»', '34çìD«r»¨']
34çìD« # Do the same as above
# STACK: ['"34çìD«r»¨"34çìD«r»', '"34çìD«r»¨"34çìD«r»¨']
r # Reverse the items on the stack
# STACK: ['"34çìD«r»¨"34çìD«r»¨', '"34çìD«r»¨"34çìD«r»']
» # Join all items on the stack by newlines
# STACK: ['"34çìD«r»¨"34çìD«r»¨\n"34çìD«r»¨"34çìD«r»']
# (after which the result is output implicitly)
```
[Answer]
## [Ruby](https://www.ruby-lang.org/en/), 60 \* 2 bytes
This is essentially a quine relay but within one language. Here is `a.rb`:
```
eval s=%q[1;puts "eval s=%q[#{s[0][?1]&&?2||?1}#{s[1..]}]"]
```
The `b.rb` is only different in one symbol:
```
eval s=%q[2;puts "eval s=%q[#{s[0][?1]&&?2||?1}#{s[1..]}]"]
```
Testing:
```
$ ruby b.rb > c.rb
$ diff c.rb a.rb
$ ruby a.rb > c.rb
$ diff c.rb b.rb
$ ruby b.rb >> c.rb
$ ruby c.rb
eval s=%q[1;puts "eval s=%q[#{s[0][?1]&&?2||?1}#{s[1..]}]"]
eval s=%q[2;puts "eval s=%q[#{s[0][?1]&&?2||?1}#{s[1..]}]"]
```
] |
[Question]
[
# Leon's story
Leon is a professional sling shooter and he comes to a shooting range everyday to practice. A casual target is not a challenge for him anymore so before shooting he first covers the target of radius `1.0` with `k` rectangle stickers. He then fires `n` shots that cannot hit the stickers.
[](https://i.stack.imgur.com/4EyRy.png)
What's special about Leon is that he always shoots randomly but with a [uniform distribution](https://stackoverflow.com/questions/5837572/generate-a-random-point-within-a-circle-uniformly).
Leon everyday takes on a bigger challenge and puts more stickers. However he started noticing that **shooting takes too much time** now so he decided to ask you for the best strategy.
---
# Task
Implement a program which will randomly pick `n` points with the **lowest time complexity** possible. Each point should be inside a circle target, and none of them lands in any of `k` rectangle stickers.
**Input:**
List of `k` rectangles in whatever form fits you.
Eg. where each rectangle is a list of:
```
[x_min, x_max, y_min, y_max]
```
The list could be:
```
[[0.1, 0.3, -0.2, 0.1], [-0.73, -0.12, 0.8, 1.4]]
```
**Output:**
List of coordinates of `n` points in whatever form fits you.
**Rules:**
* Points have to be picked randomly with [uniform distribution](https://stackoverflow.com/questions/5837572/generate-a-random-point-within-a-circle-uniformly)
* Every point lays inside a circle
* None of the points lays inside a rectangle sticker
* Stickers can overlap each other
* Circle's radius is equal to `1.0` and its center is at coordinates `(0.0, 0.0)`
* Every coordinate is in form of floating point number
* For edge cases - choose whatever fits you
---
**EDIT:**
Thanks to @Luis Mendo and @xnor it turned out that one more rule might be useful.
* With each new sticker `1/4` of the remaining board will be covered. This means that having `k` stickers the uncovered part of the target will be `(3/4)^k` of the whole.
---
## Rating
**The best time complexity wins!**
**EDIT:**
For the sake of rating we will assume that `k` and `n` are linearly proportional, meaning that `O(k^2 + n)` will be rated equally to `O(k + n^2)`
[Answer]
# Area-based algorithm, \$O(k^2+n\log(k))\$
Our general strategy is to instead select points (outside the sticker rectangles) from the square (-1,-1) to (1,1), then repeat if we don't get a point within the circle. On average, we will have to select \$\frac{4}{\pi}\$ points from the square for each point in the circle.
The runtime is not depend on rectangle coverage, but it does depend on measures of rectangle intersection (denoted `L` in the complexity analysis in the code). For the listed complexity, I use \$L=O(k)\$, which is probably not tight. If \$L=O(\log(k))\$ can be proven, then the complexity is \$O((k+n)\log(k))\$ (see `get_heights` for an algorithmic alternative).
Define "open area" to be the area that points could be generated in. Recall that we are using a square instead of a circle, so the total area is piece-wise linear in x.
1. Precompute the total open height function \$h(x)\$ (this is piece-wise constant, so store the change at each transition: either the start or end of a new rectangle). Similarly, pre-compute the cumulative areas \$\int\_{-1}^{x} h(x)\$, which is piece-wise linear, so once again store the value at each transition. This can be done in \$O(k \log(k))\$ time
2. Precompute the intervals on which y coordinates can be distributed for a given x (again, only storing this interval on each transition). This might be able to be done in \$O(k \log(k))\$, but this algorithm only succeeds at \$O(k^2)\$ time
3. Generate points. For each point: (average \$\frac{4}{\pi} n\$ times for a total runtime of \$O(n\log(k))\$
a. Choose a random value \$r\$ for the area (\$O(1)\$)
b. Find \$x\$ such that \$\int\_{-1}^{x} h(t) dt = r\$. This is accomplished through binary search on the pre-computed heights \$h\$ and cumulative areas \$\int h\$, so this is done in \$O(\log(k))\$ time
c. Choose a random value \$y\$ for the given x such that (x,y) is in an open area. Through similar binary search as 3b, this is done in \$O(\log(k))\$ time
d. Reject the point if it is outside the circle (constant factor 4/pi)
The total runtime is \$O(k\log(k)) + O(k^2) + O(n\log(k)) = O(k^2+n\log(k))\$
In the following example images, I used the same n=10000, so more rectangle coverage meant a higher density of points.
[](https://i.stack.imgur.com/dVdh9m.png)
[](https://i.stack.imgur.com/97TSFm.png)
[](https://i.stack.imgur.com/v1jZ0m.png)
Full python code below, including matplotlib display:
```
import math
import random
# for binary search
import bisect
# matplotlib for plotting the output points
import matplotlib.pyplot as plt
import matplotlib
def find_le(ls, x):
# find_le is O(log(|ls|))
# Find rightmost value less than or equal to x in ls
i = bisect.bisect_right(ls, x)
return i-1, ls[i-1]
class Interval:
def __init__(self, lo, hi):
# each range is tuple (lo, hi)
# ranges shall be sorted in ascending order
# each range does not overlap with other ranges
self.ranges = [(lo, hi)]
def remove(self, lo, hi):
new_ranges = []
for self_range in self.ranges:
if lo <= self_range[0] <= hi < self_range[1]:
new_ranges.append((hi, self_range[1]))
elif self_range[0] < lo <= self_range[1] <= hi:
new_ranges.append((self_range[0], lo))
elif self_range[0] < lo < hi < self_range[1]:
new_ranges.append((self_range[0], lo))
new_ranges.append((hi, self_range[1]))
elif lo <= self_range[0] < self_range[1] <= hi:
pass
elif hi <= self_range[0] or self_range[1] <= lo:
# no overlap
new_ranges.append(self_range)
self.ranges = new_ranges
def cache_lengths(self):
# If L is the number of subintervals of this Interval
# then cache_lengths is O(L) ⊂ O(k)
# in cum_lengths, (0.6, 0.7) means that the total length to the
# left of x=0.7 in this interval is 0.6
self.cum_lengths = [(0, -1)]
last_length = 0
for self_range in self.ranges:
length = self_range[1] - self_range[0]
self.cum_lengths.append((last_length, self_range[0]))
last_length += length
self.total_length = last_length
def random_point(self):
# If L is the number of subintervals of this Interval
# then random_point is O(log(L)) ⊂ O(log(k))
r = random.random()*self.total_length
# This find_le is O(log(L))
i, (length_left, x_left) = find_le(self.cum_lengths, (r,))
return (r - length_left) + x_left
def __repr__(self):
return "I" + str(self.ranges)
def interval_complement(rects):
# O(L) where L is the length of rects list
interval = Interval(-1, 1)
for rect in rects:
interval.remove(rect.bottom, rect.top)
return interval
class Rect:
def __init__(self, left, right, bottom, top):
self.left = min(left, right)
self.right = max(left, right)
self.bottom = min(bottom, top)
self.top = max(bottom, top)
self.width = self.right - self.left
self.height = self.top - self.bottom
def __repr__(self):
return f"Rect({self.left}, {self.right}, {self.bottom}, {self.top})"
def overlap(self, others):
# returns vertical (y) overlap between self and other rects
total_overlap = 0
# https://pyinterval.readthedocs.io/en/latest/guide.html#operations is
# looking so tempting right now, but unions/merges would
# require Principle Inclusion-Exclusion which can be k^2 worst case
starts = sorted(others, key=lambda rect: rect.bottom, reverse=True)
ends = sorted(others, key=lambda rect: rect.top, reverse=True)
active_rects = set()
overlap_start = self.bottom
while ends:
if starts and starts[-1].bottom < ends[-1].top:
active_rect = starts.pop()
if not active_rects and active_rect.bottom > self.bottom:
# This is the start of an overlap interval
overlap_start = active_rect.bottom
active_rects.add(active_rect)
else:
active_rect = ends.pop()
active_rects.remove(active_rect)
if not active_rects:
# This is the end of an overlap interval
# Rare cases of negative = started and ended below start of self
total_overlap += max(0, min(active_rect.top, self.top) - overlap_start)
return total_overlap
def as_matplotlib_rect(self):
return matplotlib.patches.Rectangle((self.left, self.bottom), self.width, self.height)
def get_heights(rects):
# get_heights is O(k log(k)) total
# Sorting: O(k log(k))
# Use these lists as a queue
starts = sorted(rects, key=lambda rect: rect.left, reverse=True)
ends = sorted(rects, key=lambda rect: rect.right, reverse=True)
# list of tuples (open height starting at x, x, open intervals starting at x)
heights = [(2, -1, Interval(-1,1))]
active_rects = set()
while ends:
# inner loop performed once for k left edges and k right edges,
# so this is O(k)
if starts and starts[-1].left < ends[-1].right:
# next x-pos is the start of a new rect
rect = starts.pop()
height_diff = rect.height - rect.overlap(active_rects)
height = heights[-1][0] - height_diff
active_rects.add(rect)
# interval_complement is O(L) so this is O(k^2), not sure if it is O(k log(k))
heights.append((height, rect.left, interval_complement(active_rects)))
else:
# next x-pos is the end of an old rect
rect = ends.pop()
active_rects.remove(rect)
# rect.overlap is O(L) as well
height_diff = rect.height - rect.overlap(active_rects)
# Two choices to get O(k log(k)):
# 1. prove that |active_rects| is O(log(k)) under the given approaches
# 2. avoid using interval_complement on each transition using some increments approach, and avoid doing rect.overlap on each transition
height = heights[-1][0] + height_diff
heights.append((height, rect.right, interval_complement(active_rects)))
heights.append((2, 1, Interval(-1,1)))
# cum_areas is the cumulative areas from -1 to x (of not rects)
# Not subtracting curve because we will be sampling from square
cum_areas = [(0, -1, Interval(-1, 1))]
last_height = 2
for height, x, interval in heights[1:]:
last_area, last_x, _ = cum_areas[-1]
new_area = (x-last_x)*last_height
cum_areas.append((last_area + new_area, x, interval))
last_height = height
return (heights, cum_areas)
def random_pick_points(rects, num_points):
# random_pick_points is O((n+k) log(k))
# Step 1. Precompute heights: O(k log (k))
heights, cum_areas = get_heights(rects)
total_area = cum_areas[-1][0]
points = []
# Step 2. Precompute vertical intervals: O(k)
for _, _, y_interval in cum_areas:
y_interval.cache_lengths()
# Step 3. Sample points outside rects and within circle
# Total time complexity of this loop is O(n log(k))
while len(points) < num_points:
# This loop is reached average (4/pi)*n = O(n) times
# Each occurence has complexity O(log(k))
# Step 3a. Choose a random area value
area = random.random()*total_area
# Step 3b. Choose the x value such that area is the total area
# outside rects and within 2x2 square to the left of x
# There are 2k+1 total cum_areas so this find_le is O(log(k))
i, (area_left, x_left, y_interval) = find_le(cum_areas, (area,))
height, _, _ = heights[i]
x = x_left + (area - area_left) / height
# Step 3c. Choose a y value uniformly in the open spaces of that x value
# Interval.random_point() is O(log(k))
y = y_interval.random_point()
# Step 3d. Rejection sample until points are inside the circle
# On average, takes constant 4/pi random points to land within the circle
if x*x + y*y < 1:
points.append((x, y))
# Done!
return points
def display_points(rects, points):
fig, ax = plt.subplots(1)
ax.plot(*zip(*points), 'ko', markersize=1, alpha=0.5)
ax.axis([-1, 1, -1, 1])
ax.add_collection(
matplotlib.collections.PatchCollection(
[rect.as_matplotlib_rect() for rect in rects],
facecolor = 'r', edgecolor='None', alpha=0.5
)
)
plt.show()
def display_random_points(rects, num_points):
points = random_pick_points(rects, num_points)
display_points(rects, points)
def random_rects(k):
return [Rect(*[random.random()*2-1 for _ in range(4)]) for i in range(k)]
k = 20
# rects = random_rects(k)
# print("Rects:", rects)
n = 10000
# print("Points:", random_pick_points(rects, n))
display_random_points(random_rects(k), n)
```
[Try it online](https://tio.run/##tVlbb9vGEn7Xr9hGL6RNyZZbnAMI9Xk5TYEAQVMkKXAAwyUociXtEbXLcJexhKYvfezP7B9JZ/bGXVJyhBYNjFgi57Zz@WZ23BzVVvCvP39m@0a0iuwLtZ3Yz23BK7GfTMlatGTFeNEeiaRFW3qKFZO0VJNJRddkzXiV1zSpZUYO6XJC4N/UPSVMkjdJLTbJp1p@SlP79nt4S1q22aq9kIp8LOqOkppKSdS24ATU0g9dURMlyIEwTmqpGRm5t6rn5leuZVjVmqSlqms5YbNFBlwP8PtxMinrAkS/4oq2oMqYiKbnOeNM5Xkiab0GepGRLbNHMIbSotyiPzb6JKpr4EiJpQvINIUkclvUNVlRIsFJtELLC1lSXjG@gUNVtD0tuhLAzIUi4iNt66IhT0xtiVBb2lrRng8tnVt19@TB2QKHdIdq6R7EnD/Sm@R1StiavNYn2lLCu/0KFIk1kR1E2zhJ4ne1Zb3bvAhOn/Legkf/HLMFtebWXzw0trdAB3INlpFvA/KH20f4vmXxw8VjzBernxdNA85Nki3LYq40jdhoDQqHuoYGLIwBFymMZKGXL1b4F0/4JYV/xzEnI3GJYxqoqoE4SS85Ti88PZPYPU@f2CUUDAVM4Ru1lVpGlNev/kZKT5GLxxoMdEGt/PH7b/Bhl04Cckjusts70owkt/N/ZeR2/u@U7GnBNY4pbYoSCoDMECKewbNATk3XCs063AMvStX2OYvRBBAc@yjQqxHgNiOzRdqXIWCdsgTw/vavlKfnjrNgFmdJxDI0zadgYE4W8w9yMbT7@t7aEB9d@7I/W8ARwJ9uXnkjwIn/SJKECvr29jp1iYLfdsHZWrDU8MzNryS9Gp0mUPIelY/a5@tAIhR1YthyzB/offp3CopcMx6GAzjaLDTKtMmkhaAGolJybYWZ3u68kpdiD61vT8GnLfRd6fu8rpAnaFS0d6wNkMBeBLSkZlKZ/u3y@t57N8FGvTCGYYYiB@am5uwj5zjntru1egYQSol9pmnBm008Abjw2e7/FojOd37tRj1MZMSJRYnLOAF1ud6TPeNJwDIEMXyGVMXhGSqjxQoLVQ5TvrGiztM8scpXq9U@6@2NabfUWuelz0J7JoGHWtq01kOBH6x71y/QockvXs2vGfmlN8B/M2L9V1D4a/qi12IHHhsGPfHIqGCNOkmATrESUic5pn5MWlH1RKkBMgK15UYmzB0vw5SZYwkRcUq2SjVyeXPTHIMEK8CbtBKlnDNxQ/lNXSgq1c2mYxWdw8RaT0VD20IxwbFJhGguxA5HPQkwT/eNws8mHlw8QWJ1inQc2W72tMVG9yS6uopO@6FjUEo/toyXDIfNV7ysOwk8s5cH@wnKjcHoWMKgDKPm7uc7ENPCFF0Wsm8tUhWtwgZhRtHEuDYjO3q8r4v9qiq0m5ZkUEngJknv37dd0JoBxy@WBAE@J6YoFftIc4MJmIAq6V/a@OTabpeeNicdDZwbPILWjKZJe1zMAfPxAQZ/V2Pfah79BMwbDyiBYahZ888b0STjGQtU4ZweHQWVBg@c1v@EZxgrDcDewqY5usBM9hnOhk0o/Df02diI544KLbqqkuBBesEsF7sK3XrGUZEiC9qRrktce4nXKJb95T6bkrcFFBjWim71nG4KVOgCD7c2jCdIhU8rWounPi4Yz5NCY4i5NngNcxlCexgUXRwOB1NA3iiCo@4ciTUNeUNVbiBcDhpx8MZMDTtiJxEjx5K9gyIGWFqGBPbVT5KiR@F/bNiQ1/BDPnS0M6gyRBSt/hwM2L43woEYSp4VYbvxWMZU26fnNLyPS5IAHnNiO5s2E4EX5u9Dhj/6bT/fRQRGovMbjtN3OE5n0XyySO14fRbBTiETXhI4dCNoCg2BhgHTzR5ySvCS6klnZ4Z/WmEjwJzb2V6hn2SBHGwnNuP1PeSLuKcFB6in5cbFNIXMP4ADZo04AUB4/9JRiHi@BJDGjXnF1muceTGINigz8811@9CPp0QAtw0Jmo8X0lkofPIsoo2hbNoPnv0c6693sXd/vkszjUOyA5gADzM1KKeB6PdvvnuzJN@/@t/g@UumZ5GmhUOb2@Cn0NRPBGFofFswzJAelQDL9maVhDHBg8OUjdkD5vLNCbcF937qisfX4qlRPopDYMQY@0@lS4C8dXU2W870iFP9YRy5fzCjrs9m1LPOtKh0qTeHsgBdxuDiYA3va5AVhfcwPOhq057M83ULg8VsYfaiiTAdMzj0lPygU3elWrQGQK7sWuBe0bLoANif4IfZFWUBhiOFlik/dKBBy@it8NuFbHhds3ioL@DewXf@Euc8dsiCVQb3EVgsg6WXloH6MvMReHIQ5q3AeEWrR3wKBMlhZujTq8AMT@n540WEZr72ciITgwKIDxaIdvdme5Ss15OaBu22A6zcmRWBdF2Od3Zp0PfsMbHBmoRf79JBd36naEMWc7gaUMy5TlHnT9/LiScfmwfHGM8Ok354sV6N3O52PNY0v@y1xtxFxvgLmu@0y75bYVLkGf4c8zAjvLo@H3qCebzwixzx9Zy8wwSmzjjRKQn3M9KP5LhDRxWsLWtqed/rZZxigKumcA9MHf3GR3dqHQAeOd90d7AjsfGD3tpHcznc3TgxLW74cZ4E1xQbSpJvbhqWXnFwJGhItRnh7fEl/kFAlFCxGuW3ELTAyHGrcK4o5uS/WyGgvAubURotzF9V@tuXCfBwE9VHfyR35eUiFh3sX2lkB1bqfqYlWqQyW86BmLMxuTvcWcSxG9F@Dxo5E7dKSHS3u15YFX1Cu749WpXtBqsyJI8WZWEWhkszL9syhQszB2m5gScHZazHpgM8NvIBYDQ/NCmvOyU3ZABRzs9lEL@j9XLHGc6L9dHshKkZYmVTlNRuKHF6HYR46mF6Hm1B09O@OYLBQbXFLCMrqzl5S/8PkcQNhDS113HFaleBGCjGdcB17@rrzm4KuauEjKhiRzG7OcySMIphYbjUtdIgL@ogY05IhNnscHUAXx@vjlCQi3hgMWI8@APMHz2Ufic4/SqEc0M8iRBcJy34axkSPuil19XDsIruoCdrjNOrS9xvJ9@kj6l@xvpnO/w73Q5b5e3EXSIG6iZNi/7X2zW5fJG57o6osbi9da9/NNCD7883nDT9/PlP) I guess, if you can read a list of points.
] |
[Question]
[
In the plane (\$\mathbb R^2\$) we can have at most five distinct points such that the distances from each point to every other point (except itself) can assume at most two distinct values.
An example of such an arrangement is a regular pentagon - the two different distances are marked with red and blue:

### Challenge
Given a number \$n = 1,2,3,\ldots\$ find the size \$s\_n\$ of the largest 2-distance set in \$\mathbb R^n\$.
### Definitions
* We measure the *Euclidean distance* \$d(a, b) = \sqrt{\sum\_{i=1}^n (a\_i - b\_i)^2}\$.
* A set \$S \subseteq R^n\$ is a 2-distance set if the number of distinct distances \$| \{ d(a,b) \mid a,b \in S, a \neq b\}| = 2\$.
### Details
Any output format defined in [sequence](/questions/tagged/sequence "show questions tagged 'sequence'") is allowed.
### Examples
```
n = 1, 2, 3, 4, 5, 6, 7, 8
s_n = 3, 5, 6, 10, 16, 27, 29, 45
```
This is [OEIS A027627](https://oeis.org/A027627), and these are all the terms that we know so far. Answers to this challenge are expected to be able to find *any* term of this sequence - given enough ressources - not just the first eight.
[Answer]
# [Mathematica](https://www.wolfram.com/mathematica/), ~~220~~ 218 bytes
```
For[n=1,1>0,n++,For[m=1,1>0,m++,x=Array[a,{m,n}];d=Table[(Norm[x[[i]]-x[[j]]]^2-1)*(Norm[x[[i]]-x[[j]]]^2-y)==0,{i,1,m-1},{j,i+1,m}];If[Not[CylindricalDecomposition[Flatten@{d,y>0},Flatten@{y,x}]],Break[]]];Print[m-1]]
```
[Try it online!](https://tio.run/##dY7LCsIwEEV/x9opNG5LxBcFN8VFd8MIsY2Y2iQSIzSUfnuNC925mplz4czVwt@kFl41Yp5L69BwBrV7STBpCh@gv0BHMPCtcyKggFGDmahoeS0uvcRFZZ3GAVERZXF0RHReZSxZ/klCwnkOowIGOmMTjB2oNO7RebxiZT3uQ69M62Kz/iAbqx/2qbyyBsteeC/NZmwhrPMJfneAYSKCnZPijvFNcXLKeIx@onl@Aw) Un-golfed version:
```
For[ n = 1, 1>0, n++,
For[ m = 1, 1>0, m++,
x = Array[a, {m, n}];
d = Table[(Norm[x[[i]] - x[[j]]]^2 - 1)*(Norm[x[[i]] - x[[j]]]^2 -
y) == 0, {i, 1, m - 1}, {j, i + 1, m}];
If[Not[
CylindricalDecomposition[Flatten@{d, y > 0}, Flatten@{y, x}]],
Break[]]
];
Print[m - 1]
]
```
In this code, we apply a key tool from real algebraic geometry. A [semialgebraic set](https://en.wikipedia.org/wiki/Semialgebraic_set) is a subset of \$\mathbb{R}^d\$ defined by polynomial equalities and inequalities. We may identify the set of 2-distance subsets of \$\mathbb{R}^n\$ of cardinality \$m\$ with a semialgebraic subset of \$\mathbb{R}^{mn+2}\$. We force one of the distances to equal 1 without loss of generality, which means our semialgebraic set is a subset of \$\mathbb{R}^{mn+1}\$. We denote the other distance (squared) by \$y\$.
For which values \$Y\subseteq\mathbb{R}\$ of \$y\$ does there exists a size-\$m\$ subset of \$\mathbb{R}^n\$ with squared distances \$\{1,y\}\$? This can be answered with the help of [Tarski--Seidenberg](https://en.wikipedia.org/wiki/Tarski%E2%80%93Seidenberg_theorem), which says that the projection of any semialgebraic set is semialgebraic. In our case, this means there is some univariate polynomial \$p\$ and relation \$\*\in\{=,<,\leq\}\$ such that \$Y=\{y\in\mathbb{R}:p(y)\*0\}\$. This projection may be accomplished using [cylindrical algebraic decomposition](https://en.wikipedia.org/wiki/Cylindrical_algebraic_decomposition) (CAD), which enjoys an [implementation in Mathematica](https://reference.wolfram.com/language/ref/CylindricalDecomposition.html).
Given a set of polynomial equalities and inequalities, as well as an ordered list of variables, Mathematica's implementation returns either an explicit description of every point in the corresponding semialgebraic set, or `False` if the set is empty. In the above code, we run CAD for increasingly larger values of \$m\$ until we get `False`, at which point we know that \$s\_n=m-1\$. Sadly, the runtime of CAD is doubly exponential in the number of variables, and so we shouldn't expect this approach to determine \$s\_9\$ any time soon. In fact, a minute of runtime only gives \$s\_1=3\$.
] |
[Question]
[
**Closed**. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Add details and clarify the problem by [editing this post](/posts/186408/edit).
Closed 4 years ago.
[Improve this question](/posts/186408/edit)
**Background**
There are self-extracting `.ZIP` files. Typically they have the extension `.EXE` (and by executing the file they will be extracted) but when renaming them to `.ZIP`, you can open the file with some ZIP extracting software.
(This is possible because `.EXE` files require a certain header but `.ZIP` files require a certain trailer so it is possible to build a file that both has an `.EXE` header and a `.ZIP` trailer.)
**Your task:**
Create a program that creates "self-displaying" image files:
* The program shall take some 64x64 image (at least 4 colors shall be supported) as input and some "combined" file as output
* The output file of the program shall be recognized as image file by common image viewers
* When opening the output file with the image viewer, the input image shall be displayed
* The output file shall also be recognized as executable file for any operating system or computer type
(If a file for an uncommon operating system or computer is produced, it would be nice if an open-source PC emulator exists. However, this is not required.)
* When executing the output file, the input image shall also be displayed
* It is probable that renaming the file (for example from `.PNG` to `.COM`) is necessary
* It is not required that the program and it's output file run on the same OS; the program may for example be a Windows program and output files that can be executed on a Commodore C64.
**Winning criterion**
* The program that produces the **smallest output file** wins
* If the size of the output file differs depending on the input image (for example because the program compresses the image), the the **largest possible** output file created by the program representing a 64x64 image with up to 4 colors counts
**By the way**
I had the idea for the following programming puzzle when reading [this question on StackOverflow.](https://stackoverflow.com/questions/56454930/is-it-possible-to-execute-a-script-stored-within-a-jpeg-file)
[Answer]
# 8086 MS-DOS .COM file / BMP, output file size = 2192 bytes
## Encoder
The encoder is written in C. It takes two arguments: Input file and output file. The input file is a 64x64 RAW RGB image (meaning it is simply 4096 RGB triplets). Number of colours is limited to 4, so that the palette can be as short as possible. It is very straight-forward in its doings; it merely builds a palette, packs pixels pairs into bytes and glues it together with pre-made headers and the decoder program.
```
#include <stdio.h>
#include <stdlib.h>
#define MAXPAL 4
#define IMAGESIZE 64 * 64
int main(int argc, char **argv)
{
FILE *fin, *fout;
unsigned char *imgdata = malloc(IMAGESIZE * 3), *outdata = calloc(IMAGESIZE / 2, 1);
unsigned palette[MAXPAL] = {0};
int pal_size = 0;
if (!(fin = fopen(argv[1], "rb")))
{
fprintf(stderr, "Could not open \"%s\".\n", argv[1]);
exit(1);
}
if (!(fout = fopen(argv[2], "wb")))
{
fprintf(stderr, "Could not open \"%s\".\n", argv[2]);
exit(2);
}
fread(imgdata, 1, IMAGESIZE * 3, fin);
for (int i = 0; i < IMAGESIZE; i++)
{
// BMP saves the palette in BGR order
unsigned col = (imgdata[i * 3] << 16) | (imgdata[i * 3 + 1] << 8) | (imgdata[i * 3 + 2]), palindex;
int is_in_pal = 0;
for (int j = 0; j < pal_size; j++)
{
if (palette[j] == col)
{
palindex = j;
is_in_pal = 1;
}
}
if (!is_in_pal)
{
if (pal_size == MAXPAL)
{
fprintf(stderr, "Too many unique colours in input image.\n");
exit(3);
}
palindex = pal_size;
palette[pal_size++] = col;
}
// High nibble is left-most pixel of the pair
outdata[i / 2] |= (palindex << !(i & 1) * 4);
}
char BITMAPFILEHEADER[14] = {
0x42, 0x4D, // "BM" magic marker
0x90, 0x08, 0x00, 0x00, // FileSize
0x00, 0x00, // Reserved1
0x00, 0x00, // Reserved2
0x90, 0x00, 0x00, 0x00 // ImageOffset
};
char BITMAPINFOHEADER[40] = {
0x28, 0x00, 0x00, 0x00, // StructSize
0x40, 0x00, 0x00, 0x00, // ImageWidth
0x40, 0x00, 0x00, 0x00, // ImageHeight
0x01, 0x00, // Planes
0x04, 0x00, // BitsPerPixel
0x00, 0x00, 0x00, 0x00, // CompressionType (0 = none)
0x00, 0x00, 0x00, 0x00, // RawImagDataSize (0 is fine for non-compressed,)
0x00, 0x00, 0x00, 0x90, // HorizontalRes
// db 0, 0, 0
// nop
0xEB, 0x1A, 0x90, 0x90, // VerticalRes
// jmp Decoder
// nop
// nop
0x04, 0x00, 0x00, 0x00, // NumPaletteColours
0x00, 0x00, 0x00, 0x00, // NumImportantColours (0 = all)
};
char DECODER[74] = {
0xB8, 0x13, 0x00, 0xCD, 0x10, 0xBA, 0x00, 0xA0, 0x8E, 0xC2, 0xBA,
0xC8, 0x03, 0x31, 0xC0, 0xEE, 0x42, 0xBE, 0x38, 0x01, 0xB1, 0x04,
0xFD, 0x51, 0xB1, 0x03, 0xAC, 0xD0, 0xE8, 0xD0, 0xE8, 0xEE, 0xE2,
0xF8, 0x83, 0xC6, 0x07, 0x59, 0xE2, 0xEF, 0xFC, 0xB9, 0x00, 0x08,
0xBE, 0x90, 0x01, 0xBF, 0xC0, 0x4E, 0xAC, 0xD4, 0x10, 0x86, 0xC4,
0xAB, 0xF7, 0xC7, 0x3F, 0x00, 0x75, 0x04, 0x81, 0xEF, 0x80, 0x01,
0xE2, 0xEE, 0x31, 0xC0, 0xCD, 0x16, 0xCD, 0x20,
};
fwrite(BITMAPFILEHEADER, 1, 14, fout);
fwrite(BITMAPINFOHEADER, 1, 40, fout);
fwrite(palette, 4, 4, fout);
fwrite(DECODER, 1, 74, fout);
// BMPs are stored upside-down, because why not
for (int i = 64; i--; )
fwrite(outdata + i * 32, 1, 32, fout);
fclose(fin);
fclose(fout);
return 0;
}
```
## Output file
The output file is a BMP file which can be renamed .COM and run in a DOS environment. Upon execution, it will change to video mode 13h and display the image.
A BMP file has a first header BITMAPFILEHEADER, which contains among other things the field ImageOffset, which denotes where in the file the image data begins. After this comes BITMAPINFOHEADER with various de-/encoding information, followed by a palette, if one is used. ImageOffset can have a value that points beyond the end of any headers, allowing us to make a gap for the decoder to reside in. Roughly:
```
BITMAPFILEHEADER
BITMAPINFOHEADER
PALETTE
<gap>
IMAGE DATA
```
Another problem is to enter the decoder. BITMAPFILEHEADER and BITMAPINFOHEADER can be tinkered with to make sure they are legal machine code (which does not produce a non-recoverable state), but the palette is trickier. We could of course have made the palette artificially longer, and put the machine code there, but I opted to instead use the fields biXPelsPerMeter and biYPelsPerMeter, the former to make the code aligned properly, and the latter to jump into the decoder. These fields will of course then have garbage in them, but any image viewer I have tested with displays the image fine. Printing it might produce peculiar results, though.
It is, as far as I know, standard-compliant.
One could make a shorter file if the `JMP` instruction was put in one of the reserved fields in BITMAPFILEHEADER. This would allow us to store the image height as -64 instead of 64, which in the magical wonderland of BMP files means that the image data is stored the right way up, which in turn would allow for a simplified decoder.
## Decoder
No particular tricks in the decoder. The palette is populated by the encoder, and shown here with dummy-values. It could be slightly shorter if it did not return to DOS upon a keypress, but it was not fun testing without that. If you feel you must, you can replace the last three instructions with `jmp $` to save a few bytes. (Don't forget to update the file headers if you do!)
BMP stores palettes as BGR (*not* RGB) triplets, padded with zeroes. This makes setting up the VGA palette more annoying than usual. The fact that BMPs are stored upside-down only adds to the flavour (and size).
Listed here in NASM style:
```
Palette:
db 0, 0, 0, 0
db 0, 0, 0, 0
db 0, 0, 0, 0
db 0, 0, 0, 0
Decoder:
; Set screen mode
mov ax, 0x13
int 0x10
mov dx, 0xa000
mov es, dx
; Prepare to set palette
mov dx, 0x3c8
xor ax, ax
out dx, al
inc dx
mov si, Palette + 2
mov cl, 4
std
pal_loop:
push cx
mov cl, 3
pal_inner:
lodsb
shr al, 1
shr al, 1
out dx, al
loop pal_inner
add si, 7
pop cx
loop pal_loop
cld
; Copy image data to video memory
mov cx, 64 * 64 / 2
mov si, ImageData
mov di, 20160
img_loop:
lodsb
aam 16
xchg al, ah
stosw
test di, 63
jnz skip
sub di, 384
skip:
loop img_loop
; Eat a keypress
xor ax, ax
int 0x16
; Return to DOS
int 0x20
ImageData:
```
] |
[Question]
[
You have a little robot with four distance sensors. It knows the layout of a room, but it has no sense of orientation other than being able to lock onto the grid orientation. You want to be able to find out where the robot is based on the readings, but it can be ambiguous because of the limited sensors.
## Challenge Explanation
You will be given a room layout and four clockwise distance readings giving the number of cells between you and a wall. There can be walls in the middle of the room and the edges of the grid are also walls. The robot cannot be placed on top of a wall.
Your objective is to list all of the locations within the room that the robot could be in that would give the given readings. Keep in mind that the robot has no sense of orientation (other than being locked to 90 degree angles on the grid- i.e. the robot will never be oriented diagonally or some other skew angle), so a reading of [1, 2, 3, 4], for example, is the same as reading [3, 4, 1, 2].
## Examples
For these examples, cell coordinates will be given as 0-indexed (x, y) pairs from the top-left cell. Readings will be given in clockwise order in a square bracketed list. Layouts will use pound signs for walls and other characters (usually dots) to represent empty cells.
### Case 1
```
. . . .
. . . .
. . # .
. . . .
```
* [1, 0, 2, 3] ==> (1, 0), (3, 1)
* [0, 0, 3, 3] ==> (0, 0), (3, 0), (0, 3), (3, 3)
* [2, 1, 1, 0] ==> (0, 2), (2, 1)
* [1, 1, 2, 2] ==> (1, 1)
### Case 2
```
# a . # a .
a # . . # a
. . # . . #
# . . # . .
a # . . # a
. a # . a #
```
* [0, 0, 1, 1] ==> every position on the grid that is a dot
* [1, 0, 0, 0] ==> all of the a's on the grid
### Case 3
```
.
```
* [0, 0, 0, 0] ==> (0, 0)
### Case 4
```
. # #
. . .
```
* [1, 2, 0, 0] ==> (0, 1)
* [0, 1, 2, 0] ==> (0, 1)
* [0, 0, 1, 0] ==> (0, 0)
* [1, 0, 1, 0] ==> (1, 1)
* [0, 1, 0, 1] ==> (1, 1)
### Case 5
```
. # . .
. . . .
. . # .
. . . .
```
* [2, 1, 1, 0] ==> (0, 2), (2, 1)
* [0, 2, 2, 1] ==> (1, 1)
* [1, 0, 2, 2] ==> (1, 1)
* [0, 3, 0, 0] ==> (0, 0)
* [1, 0, 1, 1] ==> (1, 2)
## Other Rules
* Input may be in any convenient format. Input is a grid of walls and spaces and a list of four distances in clockwise order.
* Output may either be a list of all cells that satisfy the reading or a modified version of the grid showing which cells satisfy the reading. The exact format of the output doesn't matter as long as it is reasonable and consistent. Valid output formats *include, but are not limited to*:
+ Printing a line for each cell coordinate as an ordered pair
+ Printing the grid with `.`, `#`, and `!` for space, walls, and possible locations, respectively.
+ Returning a list of ordered pairs
+ Returning a list of indexes
+ Returning a list of lists using different values for spaces, walls, and possible locations
+ Return/print a matrix of 0s and 1s, using 1s to represent cells where the reading would occur. (It is not necessary to include walls)
+ Once again, this list is not exhaustive, so other representations are valid as long as they are consistent and show every possible valid location in a grid or list. If you are unsure, leave a comment and I will be happy to clarify.
* You may assume that a reading corresponds to at least one location on the grid.
* You may assume that the input grid is at least 1x1 in size and has at least one empty space.
* You may assume that the input grid is no larger than 256 cells in each dimension.
* You may assume that the input grid is always a perfect rectangle and not jagged.
* There is no penalty or bonus if your program happens to give sane outputs for invalid inputs.
* This is code golf, so shortest code wins.
[Answer]
# JavaScript (ES6), ~~130 128 126~~ 125 bytes
Takes input as \$(m)(l)\$ where \$m\$ is a binary matrix describing the room layout (\$0\$ = wall, \$1\$ = empty) and \$l\$ is the list of distances.
Returns another binary matrix where each valid position is marked with \$1\$.
```
m=>l=>m.map((r,y)=>r.map((v,x)=>v&!!([...'3210321'].map(d=>(g=X=>(m[Y+=~-d%2]||0)[X+=(d-2)%2]?1+g(X):0)(x,Y=y))+g).match(l)))
```
[Try it online!](https://tio.run/##rVLLboMwELzzFe6htVc4yJj20sj00J9IRDmgQGgiHhGgiEhRf50aXFJDTS@tAOOdsdeznj1G56jeVYdTsyrKOOn2osuFnwk/d/LoREhFLyD8SgVn2srg/HB3RwLHcbDHXSY/HA50LHySio0c82Bri49VfM/D65VBsLEFiVccZPzi2inZwDMD0tKtuADYKcjtze6dZADQNUndIIFyJHyU9cOuLOoyS5ysTMme5CCXDcdVPamEtf0UOy0O2hCcY3koCMYwzt4KDMhGw9@y9HT4NaoT5GJYW/I8FMjHpeOLQroYMyOPwrXVy@9FBmoVp8gLQYPZAHtzmI9p2ARWmCR5Dxu0c107o5o8XeGEmNehJgr9W4ZJ/ezGzStSDFuoyJu4YUz6y@7HmZfsVtqiS/w7oX7OF2Mwz@SSCWa3C1oQ@/RT7D803kIrqWbkZj/GDtNXe4Z7cXVTu08 "JavaScript (Node.js) – Try It Online") (with post-processed output for readability)
### Commented
```
m => l => // m[] = layout matrix; l[] = list of distances
m.map((r, y) => // for each row r[] at position y in m[]:
r.map((v, x) => // for each cell v at position x in r[];
v && // yield 0 if v = 0
!!( // otherwise, test whether we can find l[] within a
[...'3210321'] // list containing twice the results of the sensors
.map(d => // for each direction d:
(g = X => ( // g = recursive function taking X
m[Y += ~-d % 2] // add dy[d] to Y
|| 0 // use a dummy object if we're out of the board
)[X += (d - 2) % 2] ? // add dx[d] to X; if (m[Y] || 0)[X] is equal to 1:
1 + // add 1 to the final result
g(X) // and do a recursive call
: // else:
0 // yield 0 and stop recursion
)(x, Y = y) // initial call to g with X = x and Y = y
) // end of map() over directions
+ g // coerce the result to a comma-separated string,
// followed by harmless garbage
).match(l) // test whether l[] can be found in this string
// (l[] is implicitly coerced to a string as well)
) // end of map() over r[]
) // end of map() over m[]
```
[Answer]
# [Python 2](https://docs.python.org/2/), ~~234~~ ~~202~~ ~~200~~ 191 bytes
```
lambda m,a:[(i,j)for j,l in e(m)for i,c in e(l)if('#'<c)*[(''.join(L)[::-1]+'#').find('#')for L in l[:i],zip(*m)[i][:j],l[:i:-1],zip(*m)[i][:j:-1]]in[a[q:]+a[:q]for q in 0,1,2,3]]
e=enumerate
```
[Try it online!](https://tio.run/##lVNNb9wgEL3zK9ByABJigd1erDpSlGsq9U440F3csLKx13YrpX9@C9jKsp9qLGRgeG@GNzP079Nb5/J9Xb3uG93@3GjYMl1KYtmW1t0At6yB1kFD2ri1bD1vG2prghH@tqZ3kmCcbTvryAuVZfkg1L0/oVlt3SZgIvMl8BpZWsX@2p7ctVRaJcutYsEYSMf2YFHWSS13pbrXstyp4GYX3HAmWM4KpYCpjPvdmkFPZt8P1k0QP@vRQIEB@P70o1qtVpn/wPJD8ypYx76xE8GvDlMAZmpNPIVJwXwAmDNYKIqq6hGSYKEMkoJBQY/BPIKLBMwP4DiH42VfnJB9DBEHT8h5AOfnkWakP8iTa4mPy8@684NupDM/gEZeto7aMwRQnD@MftYoZGMwfaPXhmCNGc587a6nZ1YcYi/3MH/M8A77brST7Rz0Y3oz8NdgN36hJ2hHvemmSznmB@W6aWBXR6bGY@rkWGCRFPZ2GflpiLkyx@6@JO4QAv/TG/mZ0ws9seBug/hZ7Tm9lKYUJK6F44eCXGqMr6nQTz6IT7Upv9Kmpx4X3A2QiO8qabQlQ/t/ "Python 2 – Try It Online")
[Answer]
# [Charcoal](https://github.com/somebody1234/Charcoal), 42 bytes
```
PθFθ¿⁼¶ι⸿¿№E⁴E⁴⊖⌕⁺⪫KD⊕⌈η✳§⟦→↓←↑⟧⁺κμω#¦#η!ι
```
[Try it online!](https://tio.run/##RY9Na8MwDIbv/RWae5HBG/s6taeybNCxQBjslOYQEmURdezUcdb@e89NQyvQ18sjIVVt6Spb6hDSUXvuHRuPB7leNNZBLIAbwPfDWOoBxc4IBSwlZBMmdk5EkvRAE/Zmx6imZY@vCuaUUOWoI@Opxg82NWZ6HPDTssGMaJ@wo8qzNbg1NzAtT9yNHbZSxg1XZOO3pqYT5qtv/m29glVijyamL2rO3U9fKJj27xV0Up6nj9HFUsxxktrbA3fX@y8Cy3UIuRDiIdpiDstLFVUF@ZOCRwXPCl6KItz/6X8 "Charcoal – Try It Online") Link is to verbose version of code. Charcoal seems to add some padding to the output for some reason; I'm assuming it's a bug in Charcoal. Explanation:
```
Pθ
```
Print the map without moving the cursor.
```
Fθ
```
Loop over each character in the map.
```
¿⁼¶ι⸿
```
If it's a newline then move the cursor to the start of the next line.
```
⊖⌕⁺⪫KD⊕⌈η✳§⟦→↓←↑⟧⁺κμω#¦#
```
Find the distance to the wall in direction `k+m`.
```
¿№E⁴E⁴...η!ι
```
Loop over all four starting directions `k`, peek in all four clockwise directions `m`, and if the result includes the second input then print a `!` otherwise print the current character.
[Answer]
# [J](http://jsoftware.com/), 61 bytes
Takes in the grid with infinity `_` for empty tiles, `1` for walls. Returns the grid with either 0 or 1, with the latter indicating a possible position.
```
e."1 2]]0 1|:i.@4|."{_2+((,-)|.=i.2)([:<./(1+|.!.1)^:(<_))"$]
```
[Try it online!](https://tio.run/##jVHBboMwDL3zFV6K1ESlbhJ2CiAhTdppp10Ry6EqpbvsA8a/MyeEDNg6TVYU@enZfn5@HxnuO6gM7CEDCYbeEeHp9eV5vCBToNtWghrMDevHAdmn1QfOs6MYsLqhFrwxJZ64Ogz4gEq8GV5aIVjajiJJ@srwpugKnu0ak534gPWOGok6FbXpiHA59x9QXmk6wwKtBu4ViMSCj9WvFvlcq0iuhhx6uE6ApMiXgCaOY0XApZrCAfcFKAgj/dCYJREF9S/OLNTpcpMXMqSPjQzipNQi1vyk0Lqp9b0mK0I3HamhdoJWxmx82AAyQH8b873wvcv8brv0pm8MmO8QGPl6B7XwbPwC "J – Try It Online")
Can probably further be golfed by trying other arrangements of the different axes.
* `((,-)|.=i.2)` 4 directions in clockwise order: `0 1, 1 0, 0 _1, _1 0`
* `(…)^:(<_)"$` for each direction and the grid
* `^:(<_)` until the output does not change, return all intermediate steps:
* `1+|.!.1` shift the grid, pushing new 1 in at the borders, incrementing each cell.
* `[:<./` take the minimum of each cell over all steps.
* `_2+` Minus 2. We now have the 4 grids, representing each direction, with the cell representing the distance.
* `i.@4|."{` get all possible rotations of the 4 grids.
* `0 1|:` transpose so that each cell has 4 lists: the possible arrangements of the sensors.
* `e."1 2]]` set cells to 1 if the given sensor input is in the 4 lists, otherwise to 0.
] |
[Question]
[
tl;dr: Output the values where the reduced prime factorization leader changes.
Every positive integer has a unique prime factorization. Let's call the reduced prime factorization just the list of multiplicity of the prime factors, ordered by the size of the factors. For instance, the reduced prime factorization of `1980` is `[2, 2, 1, 1]`, because `1980 = 2 * 2 * 3 * 3 * 5 * 11`.
Next, let's record how often each reduced prime factorization happens, over integers in `[1, 2, ..., n]`. For instance, in `[1, 2, ..., 10]`, the following reduced prime factorizations occur:
```
[1]: 4 (2, 3, 5, 7)
[2]: 2 (4, 9)
[1, 1]: 2 (6, 10)
[]: 1 (1)
[3]: 1 (8)
```
We'll call the leader up to `n` the reduced prime factorization that occurs the most often over `[1, 2, ..., n]`. Therefore, the reduced prime factorization leader for `n = 10` is `[1]`. Ties will be broken by the size of the largest integer less than or equal to `n` with that reduced prime factorization, with smaller largest integer being better. For instance, up to `n = 60`, the reduced prime factorizations `[1]` and `[1, 1]` occur 17 times each. The maximum integer in that range giving `[1, 1]` is `58`, while the maximum integer giving `[1]` is `59`. Therefore, with `n = 60`, the reduced prime factorization leader is `[1, 1]`.
I'm interested in the values of `n` where the reduced prime factorization leader changes. Those are the values of `n` where the reduced prime factorization leader is different from the reduced prime factorization leader up to `n-1`. As an edge case, we will say that the leadership changes at `n = 1`, because a leader does not exist for `n = 0`.
Your challenge is to output.
An initial sequence of the desired output is:
```
1, 3, 58, 61, 65, 73, 77, 1279789, 1280057, 1280066, 1280073, 1280437, 1280441, 1281155, 1281161, 1281165, 1281179, 1281190, 1281243, 1281247, 1281262, 1281271, 1281313, 1281365
```
Allowed output styles are:
* Infinite output.
* The first `k` leader changes, where `k` is the input.
* The `k`th leader change, where `k` is the input.
`k` may be zero or one indexed.
This is code-golf. If you're not sure about anything, ask in the comments. Good luck!
[Answer]
# [Husk](https://github.com/barbuz/Husk), 18 bytes
```
m←ġ(←►Lk=mȯmLgpṫ)N
```
[Try it online!](https://tio.run/##yygtzv6v8Khtovmjpsb/uY/aJhxZqAEkH03b5ZNtm3tifa5PesHDnas1/f7/BwA "Husk – Try It Online")
This prints the infinite list.
The link truncates the result to the first 7 values, since the program is quite inefficient and times out after that on TIO.
The parentheses are ugly, but I don't know how to get rid of them.
## Explanation
```
m←ġ(←►Lk=mȯmLgpṫ)N No input.
N The list of natural numbers [1,2,3,4,..
ġ( ) Group into slices according to this function.
Each slice corresponds to a run of numbers with equal return values.
←►Lk=mȯmLgpṫ Function: from n, compute the reduced factorization leader in [1..n].
As an example, take n = 12.
ṫ Reversed range: [12,11,10,9,8,7,6,5,4,3,2,1]
m Map over this range:
p Prime factorization: [[2,2,3],[11],[2,5],[3,3],[2,2,2],[7],[2,3],[5],[2,2],[3],[2],[]]
g Group equal elements: [[[2,2],[3]],[[11]],[[2],[5]],[[3,3]],[[2,2,2]],[[7]],[[2],[3]],[[5]],[[2,2]],[[3]],[[2]],[]]
ȯmL Take length of each run: [[2,1],[1],[1,1],[2],[3],[1],[1,1],[1],[2],[1],[1],[]]
k= Classify by equality: [[[2,1]],[[1],[1],[1],[1],[1]],[[1,1],[1,1]],[[2],[2]],[[3]],[[]]]
The classes are ordered by first occurrence.
►L Take the class of maximal length: [[1],[1],[1],[1],[1]]
In case of a tie, ► prefers elements that occur later.
← Take first element, which is the reduced factorization leader: [1]
The result of this grouping is [[1,2],[3,4,..,57],[58,59,60],[61,62,63,64],..
m← Get the first element of each group: [1,3,58,61,65,73,77,..
```
[Answer]
# JavaScript (ES6), 120 bytes
Returns the N-th leader change, 1-indexed.
```
N=>(F=m=>N?F((F[k=(D=(n,d=2,j)=>d>n?j:n%d?D(n,d+1)+(j?[,j]:[]):D(n/d,d,-~j))(++n)]=-~F[k])>m?F[N-=p!=k,p=k]:m):n)(n=p=0)
```
### Demo
```
let f =
N=>(F=m=>N?F((F[k=(D=(n,d=2,j)=>d>n?j:n%d?D(n,d+1)+(j?[,j]:[]):D(n/d,d,-~j))(++n)]=-~F[k])>m?F[N-=p!=k,p=k]:m):n)(n=p=0)
for(let n = 1; n <= 7; n++) {
console.log('a(' + n + ') = ' + f(n))
}
```
### Commented
Helper function **D()**, returning the reduced prime factorization of **n** in reverse order:
```
D = (n, d = 2, j) => // n = input, d = divisor, j = counter
d > n ? // if d is greater than n:
j // append j and stop recursion
: // else:
n % d ? // if d is not a divisor of n:
D(n, d + 1) + ( // recursive call with n unchanged and d = d + 1
j ? // if j is not undefined:
[,j] // append a comma followed by j
: // else:
[] // append nothing
) //
: // else:
D(n / d, d, -~j) // recursive call with n divided by d and j = j + 1
```
Main function:
```
N => // N = target index in the sequence
(F = m => // m = # of times the leader has been encountered
N ? // if N is not equal to 0:
F( // do a recursive call to F():
(F[k = D(++n)] = // increment n; k = reduced prime factorization of n
-~F[k]) // increment F[k] = # of times k has been encountered
> m ? // if the result is greater than m:
F[N -= p != k, // decrement N if p is not equal to k
p = k] // update p and set m to F[p]
: // else:
m // let m unchanged
) // end of recursive call
: // else:
n // stop recursion and return n
)(n = p = 0) // initial call to F() with m = n = p = 0
```
[Answer]
# [Stax](https://github.com/tomtheisen/stax), 24 [bytes](https://github.com/tomtheisen/stax/blob/master/docs/packed.md#packed-stax)
```
Ç▓Δk/‼&²Θºk∙♥╜fv╛Pg8╝j♀§
```
This program takes no input and theoretically produces infinite output. I say "theoretically" because the 8th element will take more than a year.
[Run and debug it](https://staxlang.xyz/#c=%C3%87%E2%96%93%CE%94k%2F%E2%80%BC%26%C2%B2%CE%98%C2%BAk%E2%88%99%E2%99%A5%E2%95%9Cfv%E2%95%9BPg8%E2%95%9Dj%E2%99%80%C2%A7&i=&a=1&m=1)
The corresponding ascii representation of the same program is this.
```
0WYi^{|n0-m|=c:uny=!*{i^Q}Md
```
It keeps the last leader on the stack. Iterating over integers, if there's a distinct mode in the factor representation, and it's different than the last one, output it.
```
0 push zero for a placeholder factorization
W repeat the rest of the program forever
Y store the last factorization in the y register
i^ i+1 where i is the iteration index
{ m using this block, map values [1 .. i+1]
|n0- get the prime exponents, and remove zeroes
|= get all modes
c:u copy mode array and test if there's only one
ny=! test if mode array is not equal to last leader
* multiply; this is a logical and
{ }M if true, execute this block
i^Q push i+1 and print without popping
d discard the top of stack
if it was a leader change, this pops i+1
otherwise it pops the mode array
at this point, the last leader is on top of
the stack
```
[Answer]
# [Python 2](https://docs.python.org/2/), 145 bytes
```
m=i=0;f=[]
while 1:
i+=1;a=i;d=[0]*-~i;k=2
while~-a:x=a%k>0;k+=x;a/=x or k;d[k]+=1-x
k=filter(abs,d);f+=k,;c=f.count
if c(k)>c(m):print i;m=k
```
[Try it online!](https://tio.run/##Hc0xDoMwDEDRPafwUgkKtMCIZS6CGNJAhGUgCFI1Xbh6irr/p799/eTWOsaFmEq01PXqM/E8QtUo4Iwq1MQ4UFf29@JkFKoV/Iuz0E0gfZO2RMkooH5SALeD4NBJf9EiKBCyPPtxT/TryIcUbUaSoyH7MO69@uthwSSStiZZ0mbbefXAuJDE@AM "Python 2 – Try It Online")
## Ungolfed
```
m=0 # reduced prime factorizations leader
i=0 # current number
f=[] # list of reduced prime factorizations
while 1: # Infinite loop:
i+=1 # next number
a=i # a is used for the prime factorization
d=[0]*-~i # this lists stores the multiplicity
k=2 # current factor
while~-a: # As long as a-1 != 0:
x=a%k>0 # x := not (k divides a)
k+=x # If k does not divide a, go to the next factor
a/=x or k # If k does not divide a,
# divide a by 1,
# else divide it by k
d[k]+=1-x # add 1 to the multiplicity of k if k divides a
k=filter(abs,d) # Only keep non-zero multiplicities
# k is now the reduced prime factorization of i
f+=k, # append k to the list of reduced prime factorizations
c=f.count # c(x) := number of occurences of x in f
if c(k)>c(m): # has the current reduced prime factorization
# appeared more often than the leader?
print i;m=k # print the current number, set new leader
```
[Try it online!](https://tio.run/##jVTBjtowEL3zFVOtKpECLdkjlbfqcU/9AMTBxONl5MSOYqeEPeyv07GzoZRNI3xK5PfevDeZSX0KB2cfz@dKrGHkPECDqi1QQd1QhaBlEVxDrzKQsx5KlAqbGf2PXLRNgzaAbas947TY7kZxJfkATk8Wmx0PVCLkmw/sZ6vJUkAonas3MwBaiHykCoDF7mIGQAqCUZgE8tB6NqJdA@GAY4ZYQIntevdl9Ua3AuHAAjGUB88M9EmkastAdUkFhROzjXgcLz90rS/HyJT8bSU3t8ifXMXZF5Ae5CqHTwLWMT9AJ@Rn87S@xccb2AiwLsDcgKLfpNiczBLJLEQ3YofPswZGO4ZGZk8DuYQXB8GlbKmzF8Pcwm@sxc0z92rNYPw8XJ4GKOxPkN@Bx9LjQKIQWSaR1NbseEBW3QeSVAryIdH114qzaYCS86Fn6QtqKgM2c7n3S5X91fplS66GWHNGu3rFxl3LEfpp9ybOn3XH5GNiJ6ItYim9EGY5Osh1jVax3numu/aMB1Dor4VreQRvJ3PeZWl@0gpFJVfwtKItuCP81gFZ0HEDNWNN9lTMq2xzrXCQ/S4MMz7hZLJHMZlkMlS8Xlw6oGVdafuY6bf0IwmwMJeh75Uw/za5v7j20qdagkd@xuO7zPn8Bw "Python 2 – Try It Online")
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), ~~35~~ 34 [bytes](https://github.com/DennisMitchell/jelly/wiki/Code-page)
I feel like it's still golfable
```
ÆEḟ0µ€ĠL€M⁸’ߤ¹Ṗ?
®‘©Ç€F0;ITµL<³µ¿
```
A full program taking `k` and outputting a Jelly list representation of the first `k` leader change points.
**[Try it online!](https://tio.run/##AUoAtf9qZWxsef//w4ZF4bifMMK14oKsxKBM4oKsTeKBuOKAmcOfwqTCueG5lj8Kwq7igJjCqcOH4oKsRjA7SVTCtUw8wrPCtcK/////NQ "Jelly – Try It Online")**
] |
[Question]
[
When multiplying monomials in the Milnor basis for the Steenrod algebra, part of the algorithm involves enumerating certain "allowable matrices".
Given two lists of nonnegative integers *r1*, ... ,*rm* and *s1*, ... ,*sn*, a matrix of nonnegative integers X
[](https://i.stack.imgur.com/CZZDt.png)
is allowable if
1. The sum of the jth column is less than or equal to *sj*:
[](https://i.stack.imgur.com/VL2BB.png)
2. The sum of the ith row weighted by powers of 2 is less than or equal to *ri*:
[](https://i.stack.imgur.com/5gVIk.png)
## Task
Write a program which takes a pair of lists *r1*, ... ,*rm* and *s1*, *s1*, ... ,*sn* and computes the number of allowable matrices for these lists. Your program may optionally take m and n as additional arguments if need be.
* These numbers may be input in any format one likes, for instance grouped into lists or encoded in unary, or anything else.
* Output should be a positive integer
* Standard loopholes apply.
## Scoring
This is code golf: Shortest solution in bytes wins.
## Examples:
For `[2]` and `[1]`, there are two allowable matrices:
[](https://i.stack.imgur.com/ZLnBA.png)
For `[4]` and `[1,1]` there are three allowable matrices:
[](https://i.stack.imgur.com/7KMk6.png)
For `[2,4]` and `[1,1]` there are five allowable matrices:
[](https://i.stack.imgur.com/ixnk0.png)
## Test cases:
```
Input: [1], [2]
Output: 1
Input: [2], [1]
Output: 2
Input: [4], [1,1]
Output: 3
Input: [2,4], [1,1]
Output: 5
Input: [3,5,7], [1,2]
Output: 14
Input: [7, 10], [1, 1, 1]
Output: 15
Input: [3, 6, 16, 33], [0, 1, 1, 1, 1]
Output: 38
Input: [7, 8], [3, 3, 1]
Output: 44
Input: [2, 6, 15, 18], [1, 1, 1, 1, 1]
Output: 90
Input: [2, 6, 7, 16], [1, 3, 2]
Output: 128
Input: [2, 7, 16], [3, 3, 1, 1]
Output: 175
```
[Answer]
# JavaScript (ES7), 163 bytes
```
f=([R,...x],s)=>1/R?[...Array(R**s.length)].reduce((k,_,n)=>(a=s.map((_,i)=>n/R**i%R|0)).some(c=>(p+=c<<++j)>R,p=j=0)?k:k+f(x,s.map((v,i)=>v-a[i])),0):!/-/.test(s)
```
### Test cases
**NB**: I've removed the two most time-consuming test cases from this snippet, but they should pass as well.
```
f=([R,...x],s)=>1/R?[...Array(R**s.length)].reduce((k,_,n)=>(a=s.map((_,i)=>n/R**i%R|0)).some(c=>(p+=c<<++j)>R,p=j=0)?k:k+f(x,s.map((v,i)=>v-a[i])),0):!/-/.test(s)
console.log(f([1],[2])) // 1
console.log(f([2],[1])) // 2
console.log(f([4],[1,1])) // 3
console.log(f([2,4],[1,1] )) // 5
console.log(f([3,5,7],[1,2])) // 14
console.log(f([7,10],[1,1,1])) // 15
console.log(f([7,8],[3,3,1])) // 44
console.log(f([2,6,7,16],[1,3,2])) // 128
console.log(f([2,7,16],[3,3,1,1])) // 175
```
### Commented
```
f = ( // f = recursive function taking:
[R, // - the input array r[] splitted into:
...x], // R = next element / x = remaining elements
s // - the input array s[]
) => //
1 / R ? // if R is defined:
[...Array(R**s.length)] // for each n in [0, ..., R**s.length - 1],
.reduce((k, _, n) => // using k as an accumulator:
(a = // build the next combination a[] of
s.map((_, i) => // N elements in [0, ..., R - 1]
n / R**i % R | 0 // where N is the length of s[]
) //
).some(c => // for each element c in a[]:
(p += c << ++j) // increment j; add c * (2**j) to p
> R, // exit with a truthy value if p > R
p = j = 0 // start with p = j = 0
) ? // end of some(); if truthy:
k // just return k unchanged
: // else:
k + // add to k the result of
f( // a recursive call to f() with:
x, // the remaining elements of r[]
s.map((v, i) => v - a[i]) // s[] updated by subtracting the values of a[]
), // end of recursive call
0 // initial value of the accumulator k
) // end of reduce()
: // else:
!/-/.test(s) // return true if there's no negative value in s[]
```
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), 26 [bytes](https://github.com/DennisMitchell/jelly/wiki/Code-page)
```
UḄ€Ḥ>⁴
0rŒpṗ⁴L¤µS>³;ÇẸµÐḟL
```
A full program taking **S**, **R** which prints the count
**[Try it online!](https://tio.run/##AUsAtP9qZWxsef//VeG4hOKCrOG4pD7igbQKMHLFknDhuZfigbRMwqTCtVM@wrM7w4fhurjCtcOQ4bifTP///1szLCAzLCAxXf9bNywgOF0 "Jelly – Try It Online")**
### How?
```
UḄ€Ḥ>⁴ - Link 1, row-wise comparisons: list of lists, M
U - upend (reverse each)
Ḅ€ - convert €ach from binary (note bit-domain is unrestricted, e.g. [3,4,5] -> 12+8+5)
Ḥ - double (vectorises) (equivalent to the required pre-bit-shift by one)
⁴ - program's 2nd input, R
> - greater than? (vectorises)
0rŒpṗ⁴L¤µS>³;ÇẸµÐḟL - Main link: list S, list R
0r - inclusive range from 0 to s for s in S
Œp - Cartesian product of those lists
¤ - nilad followed by link(s) as a nilad:
⁴ - program's 2nd input, R
L - length
ṗ - Cartesian power = all M with len(R) rows & column values in [0,s]
µ µÐḟ - filter discard if:
S - sum (vectorises) = column sums
³ - program's 1st input, S
> - greater than? (vectorises) = column sum > s for s in S
Ç - call the last link (1) as a monad = sum(2^j × row) > r for r in R
; - concatenate
Ẹ - any truthy?
L - length
```
[Answer]
# [Wolfram Language (Mathematica)](https://www.wolfram.com/wolframscript/), 101 bytes
Let Mathematica solve it as a system of inequalities over the integers. I set up a symbolic array in `f` and thread over three sets of inequalities. `Join@@` just flattens the list for `Solve`.
```
Length@Solve[Join@@Thread/@{Tr/@(t=f~Array~{q=(l=Length)@#2,l@#})<=#2,2^[[email protected]](/cdn-cgi/l/email-protection)<=#,t>=0},Integers]&
```
[Try it online!](https://tio.run/##TYxBawIxEIX/SkAoCkPdJLrrwcj02NJDqd5EIbQxu7BGTEOhhPjXt6PRVUhm3jfvzex1qM1eh@ZLd1Z178bZUOPy0P6a9duhcYir2hv9Pca48mMcBrU7vXiv/07xqIatygsjHAhocZBGc0VKbD@1swaPz4EYwkIVCV5dMNb4n81T9@EbF9YWEWOMPEEUiQpVIDqryVlB1gIeScIUqgvnnQp4ke0@UAIvQUqCAjjcnQpm1CTI/jArgfEpfTIY3WD395CoCMtrQAITN6ufy8s8b6VN9w8 "Wolfram Language (Mathematica) – Try It Online")
[Answer]
# Mathematica 139 bytes
```
Tr@Boole[k=Length[a=#]+1;AllTrue[a-Rest[##+0],#>=0&]&@@@Tuples[BinCounts[#,{2r~Prepend~0}]&/@IntegerPartitions[#,All,r=2^Range@k/2]&/@#2]]&
```
[Try it online](https://tio.run/##TU5Na4QwEL33VwwIe@kUNelqoVjs9lToQcSbtRDawZV14xJjL@L@dTt@dHdDMnlv3nuTHJXd01HZ6luNZfQ5ZibeNU1N@QEi@CBd2n2uGDoF3IP/DHcA8FrXmemI@w@QUmtzx2HRKxAceInAg00BG4jjeHZD1p1qavNdpd@aTts2dxB6AeacGDqR/jl7w@R3V/u03rWlkkyijK1s1eg5w88iGP6L@EqVLik@uGINOqJgNCam0jYv@eWUfsm05MZ93/sD9mLgwhWZTehxQrhggbdM4hbDmS@ZEH1vkS@GAP0ApWTioY9XJcQnviTKy2AIEPwtHxaAZ8B13zhCpsFqkAjiX7r05dxfUkMx/gE)
Explanation: Partitions each of the *ri* into powers of 2 and then makes all tuples with one decomposition into powers of two for each integer, subtract the column totals from the list of the *si*. Count the number of tuples that make all remaining entries are positive.
] |
[Question]
[
[<< Prev](https://codegolf.stackexchange.com/questions/149820/advent-challenge-3-time-to-remanufacture-the-presents) [Next >>](https://codegolf.stackexchange.com/questions/149950/advent-challenge-5-move-the-presents-to-the-transport-docks)
Santa was able to remanufacture all of the presents that the elves stole overnight! Now he has to send them to the assembly line for packaging. He usually has a camera to supervise the assembly line both to make sure the elves are doing a good job and because assembly line pictures look nice on advertising posters [citation-needed]
Unfortunately, his camera broke, so he would like you to draw out a simulation of what the assembly line would look like!
In order to keep to assembly line working at maximum efficiency and to reduce the risk of error or failure, all present boxes have the same width so that they fit perfectly on the conveyor belt.
# Challenge
Given a list of presents represented by their dimensions, output a conveyor belt with all of the presents.
A present is drawn like such:
```
+----+
/ /|
+----+ |
| | +
| |/
+----+
```
This present has width 1, height 2, and length 4. Note that the plus-signs don't count for the side-length, so a present with length 4 actually spans 6 positions.
All presents are drawn next to each other with one space between the closest two characters; that is, the bottom-left corners of the presents are spaced such that if a present box has length `l` and width `w`, the next present box's bottom-left corner will be exactly `l + w + 4` positions right of the bottom-left corner of the previous box.
After all present boxes are drawn, the conveyor belt is drawn by replacing the space between boxes on each of the last `width + 2` lines with underscores.
The final output for present boxes with `(l, w, h)` of `[(4, 1, 2), (8, 1, 3), (1, 1, 1)]` would be:
```
+--------+
+----+ / /|
/ /| +--------+ | +-+
+----+ | | | | / /|
| | +_| | +_+-+ +
| |/__| |/__| |/
+----+___+--------+___+-+
```
# Formatting Specifications
You can choose either to take a list of 3-tuples where one of the elements is consistent across the whole list (that would be the width), or you can take the present width and then a list of 2-tuples representing the length and height of each present. You can take the inputs in any order and in any reasonable format, but the presents must be displayed in the same order that they are given as input.
You may choose any reasonable output format for the ASCII-art (including returning from a function).
# Test Cases
These test cases are given as `[(l, w, h), ...]` format.
```
[(4, 1, 2), (8, 1, 3), (1, 1, 1)]:
+--------+
+----+ / /|
/ /| +--------+ | +-+
+----+ | | | | / /|
| | +_| | +_+-+ +
| |/__| |/__| |/
+----+___+--------+___+-+
[(5, 3, 4), (8, 3, 1), (1, 3, 7)]:
+-+
/ /|
/ / |
+-----+ / / |
/ /| +-+ |
/ / | | | |
/ / | +--------+ | | |
+-----+ | / /| | | |
| | +___/ / +_| | +
| | /___/ / /__| | /
| | /___+--------+ /___| | /
| |/____| |/____| |/
+-----+_____+--------+_____+-+
[(0, 0, 0)] (this is the most interesting test case ever :P)
++
+++
++
[(8, 3, 0), (0, 3, 8)] (more zero cases)
++
//|
// |
// |
++ |
|| |
|| |
|| |
+--------+ || |
/ /+_|| +
/ //__|| /
/ //___|| /
+--------+/____||/
+--------+_____++
```
# Rules
* Standard Loopholes Apply
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so the shortest answer in bytes wins
* No answer will be accepted
Note: I drew inspiration for this challenge series from [Advent Of Code](http://adventofcode.com/). I have no affiliation with this site
You can see a list of all challenges in the series by looking at the 'Linked' section of the first challenge [here](https://codegolf.stackexchange.com/questions/149660/advent-challenge-1-help-santa-unlock-his-present-vault).
[Answer]
# [Charcoal](https://github.com/somebody1234/Charcoal), ~~96~~ 81 bytes
```
NθWS«→FυG↗→↙⁺²θ_≔I⪪ι υ≔⊟υπ≔§υ⁰ρ→↗G↑⊕π↗⊕θ→⊕ρ↓⊕π↙⊕θ ↑πP↗⊕θP←⊕ρ↓+↓πF²«↷⁴+ρ↷²+π↷¹+θ↶³
```
[Try it online!](https://tio.run/##dVFdT8MgFH0ev@KmT5dYE/dhNPVp0ZclzjQuPpu6sY6EAaOwacx@e4W2s023PcE953A4B5abzCxVJspyJrWzb277xQzu6BM5bLhggBW8sIbLHCmFXzKYqz3D5J3nG@tlg7UygI5CqsRPriQmH7riYkhO64s6yFe29ttUuAJHMexoDNFnFM5Pi4LnEp@zwuJCC26Rew4i6iWuI0iV9tfEoDvY1M7kin2ji@HOUyZQvXj12GQKQCdnDDO5NGzLpGUr1N6hDd9lQtrkAm5oU@6CUdu57xS6hRz@SW2doqo0d8JyfQIvpujLzv0N7VjXyaKb6AzT/x83qr50kPK9stWdOAlcI2/ONpOp9610dFWq@9LhVemulYY@OA7zkRzLckzuYUIeYUiG8EDK2734Aw "Charcoal – Try It Online") Link is to verbose version of code. Input is the width on the first line, then the other dimensions on following lines, ending with a blank line. Explanation:
```
Nθ
```
Input the width.
```
WS«
```
Loop over the remaining lines until the blank line is reached.
```
→FυG↗→↙⁺²θ_
```
Draw the belt between presents. The `u` variable is predefined to an empty list, which therefore does nothing on the first pass, while later on it ends up with a single element, causing this code to run once. (Using an `if` would be less golfy.)
```
≔I⪪ι υ
```
Split the dimensions at the space, cast them to integer, and save them in `u`.
```
≔⊟υπ
```
Remove the last dimension and save it in `p`.
```
≔§υ⁰ρ
```
Copy the first dimension to `r`, but leave it in `u` so that the belt gets drawn on the next loop.
```
→↗G↑⊕π↗⊕θ→⊕ρ↓⊕π↙⊕θ
```
Erase the interior of the present, in case the belt overlaps it.
```
↑πP↗⊕θP←⊕ρ↓+↓π
```
Draw the interior lines of the present.
```
F²«↷⁴+ρ↷²+π↷¹+θ↶³
```
Draw halfway around the exterior of the present, then repeat for the other half.
[Answer]
# [Pip](https://github.com/dloscutoff/pip), ~~160~~ 154 bytes
153 bytes of code, +1 for `-l` flag.
```
{YMX:_+B+3MUaRV$.({UwhlWg+^11{a<=h+w?J[sXa-haN[0hh+w]?'-XlWR'+sXlWR("/|"a<h)RV(("+|/"aCMw).sXw)@<MN[ah+w-awh]'_Xw-a+1|s]sXl+w+3}M,y}MUa)R`_ +`'_X#_<|:'_}
```
This is a function that takes a list of lists containing `[width height length]`. [Try it online!](https://tio.run/##JY1dS8MwGIXv@yteqtCG2K2hDqVWJuqVkF0UtmWE2L1o1xRrV0ghSNvfXqO7Os@B89HV3XxK5@HARVrQZ5rwLea760U4bK1u9hV9Z2zA7FFTu36TRmCkcSNj7bxaB5Fo9nlAzZ@E/nL0MdMk34WhT8eljy/ckoURljxlfCPRdSK0WgWFcEDZaJRrUkuTid/8TO6Z5McC6NEFropsTINimh/gtf4uW1OfWwPnE3T48YVVaQANSFt/9hp0WVe6h6Zsq14rr0ulBzKBW1ipf2Bwf4E7YBeIIVae8kI3R@Y5an4B "Pip – Try It Online")
### How?
Top-level explanation:
* Define a function that returns a list of lines representing one box
* Map the function to each list of dimensions given
* Concatenate the resulting lists of lines item-wise
* Do a little post-processing with regex replacements to get the underscores to behave properly
Leave a comment and I'll add a more detailed explanation.
[Answer]
# [Python 2](https://docs.python.org/2/), 508 bytes
```
def f(B):
d=B[0][1]+2;H=max(B)[0]+d+1;W=sum(sum(b[1:])+3for b in B)+len(B);r=[[' ']*i+W*['_']for i in range(d)]+[W*[' ']for _ in' '*H];o=0
for h,w,l in B:
for i in range(w+2,1,-1):r[i-1][o+i-2:o+l+i]=[' ']*(l+2)+['/'];r[h+i][o+i-1]=r[h+i][o+l+i]='/'
r[0][o:o+l+2]=r[h+1][o:o+l+2]=r[w+h+2][o+w+1:o+w+l+3]=['+']+['-']*l+['+']
for i in range(1,h+1):m=min(i,w)-1;r[i][o:o+l+2+m]=['|']+[' ']*l+['|']+[' ']*m;r[i+w+1][o+l+w+2]='|'
r[w+1][o+l+w+2]='+';o+=l+w+4
for l in r[H-1::-1]:print''.join(l).rstrip('_')
```
[Try it online!](https://tio.run/##ZVHLbsIwEDyTr/DNNutQHKiKHPnCiT/gYFkIBBRXeSBDlVbqv9Ndh0JLpSSa2RnP7jrHz/OhbYrLZbvbs72YS5OxrZ27sXfaQ1EubL3@wDIWYAu6XNrTey3o3ThtvITJvo1sw0LD5hKqXYPeMlrnOON@GGA5dHzFPZkCmeK6ed2JrfTgSGK9tEIJ8XDhy9aOM0a1g@pUlXJNNng430GhtMq1NNGFXHvXQsgL00IFwdu@t6igkOD4E/dldAcUkkt7e2PJjYZsEGnhNgUUvUH/4R0cEOCRDrShbwUTagQcF@E5tqsgsX@jaoVZ0tS2Do0IqpO5xnHCLR1qyvlKOeyac2c1ealpP25H06BMAz8UgZctWGLT/v7S3UW3yLUxuLU5xtCcOR@9tThIJUfxdI7hKPDvyMteOFEophWbSsXEJMEZQZ2gll5mGbmmiqH6fJUmV9dLgnfXWDF6fvMf6yxBki7f "Python 2 – Try It Online")
Takes a list of lists of `[height, width, length]`
] |
[Question]
[
# Challenge
Given a string input, output the demolished version of it.
# The Process
```
P
r Pr r
o o o
g g g
r r r rogr r
a -> a -> a -> a -> a -> -> -> -> ->
m m m m m
m m m m m mmar m
i i i i i i i mi m
n n n n gn gn gn gn gni mgni
g g Pg Pg roPg roPg roPgmar roPgmar roPgmar roPgmar
```
1. Place the string vertically.
2. Select a random integer between `1` and `(height of the column of characters) - 1` and a random direction (left or right).
3. Rotate that number of characters in that direction (if those spaces are unoccupied go to step 4; if not, go back to step 2).
4. Let those characters fall due to gravity.
5. Repeat until the height of the column of characters is at most `1` larger than the height of the columns next to it (i.e. it becomes impossible to further demolish ("steps 2-4") the column).
6. If there is another column of characters that is more than `1` character taller than one or more of its surrounding columns (i.e. demolish-able), repeatedly demolish that column until it is no longer demolish-able. If there are multiple demolish-able columns, completely demolish the tallest column (if there are multiple tallest columns, completely demolish the leftmost one).
7. Repeat until all columns are no longer demolish-able.
If there are space characters in the input, demolish those first, all at once.
```
C
o
d
e -> oC -> -> ...
de
G G G
o o o
l l l
f f defoC
```
## Rules
* Standard loopholes are forbidden.
* Trailing and leading newlines are allowed.
* Your program may either print or return a string/equivalent.
* The output must be non-deterministic (unless the input is not demolish-able).
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so the submissions with the smallest byte counts in their languages win!
[Answer]
# [Python 2](https://docs.python.org/2/), ~~622~~ ~~595~~ ~~573~~ ~~552~~ ~~542~~ ~~534~~ ~~527~~ ~~520~~ 515 bytes
```
from random import*
s=input()
r=range
R=choice
Z=len
L=h=Z(s)
a=[[]for _ in' '*-~h]
S=s[::-1].split()
X=-1,1
for w in S[1:]:
for i in r(Z(w)):a[h-~i*R(X)]+=w[i]
a[h]+=S[0]
while L:
H=[map(Z,a[c-1:c+2])+[c]for c in r(1,h-~h)];D=L=[(min(n,m)-C,i)for n,C,m,i in H if~-C>min(n,m)]
while D:
_,c=min(L);n,C,m=map(Z,a[c-1:c+2]);D=X[n+2>C:1+(C-1>m)]
if D:
d=R(D);l=R(r(1,C-[0,m,n][d]));w,a[c]=a[c][-l:],a[c][:-l]
for i in r(l):a[c-~i*d]+=w[i]
for l in zip(*[l+[' ']*max(H)[1]for l in a if l])[::-1]:print`l`[2::5]
```
[Try it online!](https://tio.run/##ZVKxjuMgEK2Xr6Az2LBaIl1DRBqnSJFilTRRRmjXwnaMhLGFs/Jdivx6Dhzt6aRtGJj35r1hYPxz7Qa/ejzaMPQ4VL6OwfbjEK45mpT149eVUBRUhC4NOijTDdY06Kxc49FedepMJooqBaDbIeAPbH2GcZbze6fRUU0gJRf6dRqdTUInxQUTKFHnSMVHEFJLhFPCpkQgZzJTKivo@N3mB3KiulAzWI1iKm6P8KbR3FnX4H0s3Cnoq5GcWQWGC2mKlaYFmKUZ8xQULEp1VK@3aq@A9NYTz3rKS2ZponlWsp4t7jts2zsvN98cjfDTaivRywczKgF7ul5K1A/j6HACX6w2pRQFKbnYJIkX2y71uFYHsqVrF0PqquTwFo29hlpTup6TklZpAe6kXo4guYsK/8/HpeGYNJz6ezIJdQm92ZHk4ArIcKbzvvpNdhSE/odX8X7Yafp8FTkG66@f7hNWUv7Sj0f2HoZLqPp4ywsev24310w4/glshrrBl8G12V8 "Python 2 – Try It Online")
] |
[Question]
[
Given
* a matrix `a` of characters from `u=" ╶╺╵└┕╹┖┗╴─╼┘┴┶┚┸┺╸╾━┙┵┷┛┹┻╷┌┍│├┝╿┞┡┐┬┮┤┼┾┦╀╄┑┭┯┥┽┿┩╃╇╻┎┏╽┟┢┃┠┣┒┰┲┧╁╆┨╂╊┓┱┳┪╅╈┫╉╋"`
* the coordinates of a submatrix as `x`,`y`,`w`,`h` (left, top, width>1, height>1)
* a thickness `t` of 1 (as in `┌`) or 2 (as in `┏`)
render an inner border for the submatrix with the specified thickness, taking into account existing lines.
```
x=4;y=1;w=2;h=3;t=2;
a=[' ┌───┐',
'┌┼┐ │',
'│└┼──┘',
'└─┘ ']
// output
r=[' ┌───┐',
'┌┼┐ ┏┪',
'│└┼─╂┨',
'└─┘ ┗┛']
```
When overwriting a line fragment, the new thickness should be the greater of
the old thickness and `t`.
This isn't about input parsing or finding the Kolmogorov complexity of Unicode,
so you may assume `a`,`u`,`x`,`y`,`w`,`h`,`t` are available to you as variables.
Also, you may put the result in a variable `r` instead of returning or
outputting it, as long as `r` is of the same type as `a`.
If your language forces you to put code in functions (C, Java, Haskell, etc)
and your solution consists of a single function, you can omit the function
header and footer.
Larger test:
```
x=4;y=1;w=24;h=4;t=1;
a=['┏┱─────┐ ┌┐ ┎──┲━┓',
'┠╂─────┘ ││ ┃ ┗━┛',
'┃┃ ││ ┃ ',
'┠╂──┲━━┓ ┏━━━━┓ ││ ┌╂┰┐ ',
'┃┃ ┗━━┩ ┃ ┃ └╆━┓ └╂┸┘ ',
'┃┃ │ ┃ ┃ ┃ ┃ ┃ ',
'┗┹─────┘ ┗━━━━┛ ┗━┛ ╹ ']
// output
r=['┏┱─────┐ ┌┐ ┎──┲━┓',
'┠╂──┬──┴─────────┼┼─────╂──╄━┛',
'┃┃ │ ││ ┃ │ ',
'┠╂──╆━━┓ ┏━━━━┓ ││ ┌╂┰┐│ ',
'┃┃ ┗━━╃──╂────╂─┴╆━┱──┴╂┸┴┘ ',
'┃┃ │ ┃ ┃ ┃ ┃ ┃ ',
'┗┹─────┘ ┗━━━━┛ ┗━┛ ╹ ']
```
[Answer]
# JavaScript, 218 bytes
```
(a,x,y,w,h,t,u)=>a.map((l,j)=>l.map((c,i)=>u[(g=(a,b)=>a?g(a/3|0,b/3|0)*3+Math.max(a%3,b%3):b)(u.indexOf(c),t*((j==y||j==y+h-1)*((i>x&&i<x+w)*9+(i>=x&&i<x+w-1))+(i==x||i==x+w-1)*((j>y&&j<y+h)*3+(j>=y&&j<y+h-1)*27)))]))
```
`a` should be taken as array of array of char.
```
f =
(a,x,y,w,h,t,u)=>a.map((l,j)=>l.map((c,i)=>u[(g=(a,b)=>a?g(a/3|0,b/3|0)*3+Math.max(a%3,b%3):b)(u.indexOf(c),t*((j==y||j==y+h-1)*((i>x&&i<x+w)*9+(i>=x&&i<x+w-1))+(i==x||i==x+w-1)*((j>y&&j<y+h)*3+(j>=y&&j<y+h-1)*27)))]))
x=4;y=1;w=24;h=4;t=1;
a=['┏┱─────┐ ┌┐ ┎──┲━┓',
'┠╂─────┘ ││ ┃ ┗━┛',
'┃┃ ││ ┃ ',
'┠╂──┲━━┓ ┏━━━━┓ ││ ┌╂┰┐ ',
'┃┃ ┗━━┩ ┃ ┃ └╆━┓ └╂┸┘ ',
'┃┃ │ ┃ ┃ ┃ ┃ ┃ ',
'┗┹─────┘ ┗━━━━┛ ┗━┛ ╹ '].map(x => [...x])
u=" ╶╺╵└┕╹┖┗╴─╼┘┴┶┚┸┺╸╾━┙┵┷┛┹┻╷┌┍│├┝╿┞┡┐┬┮┤┼┾┦╀╄┑┭┯┥┽┿┩╃╇╻┎┏╽┟┢┃┠┣┒┰┲┧╁╆┨╂╊┓┱┳┪╅╈┫╉╋";
output = f(a,x,y,w,h,t,u).map(x => x.join('')).join('\n');
document.write(`<pre lang="en" style="font-family: Consolas,Menlo,Monaco,Lucida Console,Liberation Mono,DejaVu Sans Mono,Bitstream Vera Sans Mono,Courier New,monospace,sans-serif;">${output}</pre>`)
```
[Answer]
# [Python 3](https://docs.python.org/3/), ~~226~~ ~~201~~ 197 bytes
```
n,m=x+w-1,y+h-1
r=[*map(list,a)]
R=range
for i in R(x,x+w):
for j in R(y,y+h):A,B=j in(y,m),i in(x,n);r[j][i]=u[sum(3**o*max((i<n*A,y<j*B,x<i*A,j<m*B)[o]*t,u.index(a[j][i])//3**o%3)for o in R(4))]
```
[Try it online!](https://tio.run/##bVLbUhpBEH3fr9iyKrU766pl4EnYB/kEXzc8UBUTloKFQijhTSH3i5J4JpiQ@91cjUkMxlz@5fwImdkFg@jU1E53T59zunun0qzly2FiUPemTMp9yp@U3wkQkvKAuEd0Kb8Ra5S/iG1C2fvEA6JPqOQ@5R9inbhPKOAPokco4CGlsm8Rt4kW8ZB4RPmXeEw8IzrEB@IT8ZJQtIrhNaWSuETcIT4Sn4lXxG9CQXYo25RXKQ@JDWKTUsWfEM@JNvGUeEHcJXaJPeIN5TrlFeItZYvyBrFFfCG@Eu8oL1NeI95TXqe8OWUYDS@ZanrzqVXvbDKVV05NOUbO8y2to3Frx3fHHK2ouc7Q3Bjd70Wz2LJcQ8UtXZ2qYpJke4xE3baGZlt/uhFB74igHcWPrUmQTjxNL65Fl6MTN0feKPafRreiYbtxQxPao5rU3jlS1Id@JnrSIwVEJP24v5MNRGJj8CFH@7Q2utEbOjm2sVri3RubmSaSBzFR1lB/sRis1OxSrmJrw80JMQjdkteYXp2Zd5vT@Zl5o@r5zlhC1ljyqrnw4rJxoVw1AzMIzSW74SqEWDBMHSvEsabGi4VFN@PpiPJLwtX5KjsUqapfyPpB1qv7K/WSnXCcslJp2HaQDp1Ft5kuOBm3kQ6UXUiXnIzwy1mn5tZng/D8csPOxWgxN6eRZxJCC5dj4aQQ2UGlGoQ12zoXWrOFstK0hmcxyizqzKoQxuAf "Python 3 – Try It Online")
Ungolfed:
```
n,m=x+w-1,y+h-1
r=[*map(list,a)]
for i in range(x,x+w):
for j in range(y,y+h):
p=u.index(a[j][i])
c=(p%3,p%9//3,p%27//9,p//27)
A,B=j in(y,m),i in(x,n)
P=(i<n*A,y<j*B,x<i*A,j<m*B)
l=sum(max(P[o]*t,c[o])*3**o for o in range(4))
r[j][i]=u[l]
```
[Answer]
## JavaScript (ES6), 174 bytes
```
r=a.map((l,j)=>l.map((c,i)=>u[c=u.indexOf(c),g=n=>c/n%3<t&&g(n,c+=n),j==y|j==h&&(i>=x&i<w&&g(1),i>x&i<=w&&g(9)),i==x|i==w&&(j>=y&j<h&&g(27),j>y&j<=h&&g(3)),c]),w+=x-1,h+=y-1)
```
```
a=`
┏┱─────┐ ┌┐ ┎──┲━┓
┠╂─────┘ ││ ┃ ┗━┛
┃┃ ││ ┃
┠╂──┲━━┓ ┏━━━━┓ ││ ┌╂┰┐
┃┃ ┗━━┩ ┃ ┃ └╆━┓ └╂┸┘
┃┃ │ ┃ ┃ ┃ ┃ ┃
┗┹─────┘ ┗━━━━┛ ┗━┛ ╹
`.match(/.+/g).map(s=>[...s]);
x=4;
y=1;
w=24;
h=4;
t=1;
u=" ╶╺╵└┕╹┖┗╴─╼┘┴┶┚┸┺╸╾━┙┵┷┛┹┻╷┌┍│├┝╿┞┡┐┬┮┤┼┾┦╀╄┑┭┯┥┽┿┩╃╇╻┎┏╽┟┢┃┠┣┒┰┲┧╁╆┨╂╊┓┱┳┪╅╈┫╉╋";
r=a.map((l,j)=>l.map((c,i)=>u[c=u.indexOf(c),g=n=>c/n%3<t&&g(n,c+=n),j==y|j==h&&(i>=x&i<w&&g(1),i>x&i<=w&&g(9)),i==x|i==w&&(j>=y&j<h&&g(27),j>y&j<=h&&g(3)),c]),w+=x-1,h+=y-1)
;document.write(`<pre style="font-family:Consolas,Menlo,Monaco,Lucida Console,Liberation Mono,DejaVu Sans Mono,Bitstream Vera Sans Mono,Courier New,monospace,sans-serif">${r.map(s=>s.join``).join`\n`}</pre>`);
```
] |
[Question]
[
*This is a tips question for golfing in Python, which is on topic for main.*
I'm looking for the shortest way to get all of the most common elements of a list in Python, in the shortest way possible. Here's what I've tried, assuming the list is in a variable called `l`:
```
from statistics import*
mode(l)
```
This throws an error if there are multiple modes.
```
max(l,key=l.count)
```
This only returns 1 item, I need to get *all* the elements of greatest count.
```
from collections import*
Counter(l).most_common()
```
This returns a list of tuples of `(element, count)`, sorted by count. From this I could pull all the elements whose corresponding count is equal to the first, but I don't see a way to golf this much better than:
```
from collections import*
c=Counter(l).most_common()
[s for s,i in c if i==c[0][1]]
```
I am sure there is a shorter way!
Also, if it can be done without variable assignment or multiple uses of `l`, I can keep the rest of the code as a lambda expression to save more bytes.
Edit: Per @Uriel's suggestion, we can do:
```
{s for s in l if l.count(s)==l.count(max(l,key=l.count))}
```
And I can alias `list.count` for a few bytes:
```
c=l.count;{s for s in l if c(s)==c(max(l,key=c))}
```
@Uriel pointed out that we can get a couple more bytes with `map`:
```
c=l.count;{s for s in l if c(s)==max(map(c,l))}
```
[Answer]
How about this one?
```
c=l.count;{x for x in l if c(x)==max(map(c,l))}
```
Enclose in `[*...]` to get a list.
] |
[Question]
[
Yesterday, I left my sandwich on the table. When I got up today, there was a bite in it... Was it mine? I can't remember...
# Problem:
Take a representation of the sandwich and my bite pattern and tell me if it was my bite or not.
# Examples:
### Example 1:
My bite pattern:
```
..
.
```
Sandwich:
```
#####
.####
..###
```
Output:
```
truthy
```
### Example 2:
My bite pattern:
```
..
..
```
Sandwich:
```
...##
..###
.####
```
Output:
```
falsy
```
### Example 3:
If there is at least 1 rotation that counts as truthy, the output is truthy.
My bite pattern:
```
.
.
.
```
Sandwich:
```
##.
#.#
.##
```
Output:
Two possible rotations (biting in the northeast or southwest corner).
```
truthy
```
### Some valid bites:
```
..
.
...
.
.
.
.
.
..
. .
..
..
.
. .
```
### Some invalid bites:
```
..
...
.
..
.
.
```
# Rules:
* My bite pattern orientation will always be for biting the northwest corner. And must be rotated to bite other corners;
* There will always be 1 and only 1 bite in the sandwich;
* The bite in the sandwich can be in any of the 4 cornes (rotated accordingly);
* Bite patterns will always be symmetrical along the main diagonal;
* Bite patterns will always be at least 1 wide and non empty;
* The sandwich will always be a rectangle with width and height equal or greater than the width of my bite pattern;
* In your input, you can choose any 2 distinct non-whitespace characters to represent the sandwich and the bite;
* Spaces in the bite pattern means that my bite does not touch that part of the sandwich.
[Answer]
# [Ruby](https://www.ruby-lang.org/), 103 bytes 101 bytes
```
->b,s{[a=s.map(&:reverse),s,s.reverse,a.reverse].any?{|t|b.zip(t).all?{|y,x|y==x.tr(?#,' ').rstrip}}}
```
[Try it online!](https://tio.run/nexus/ruby#fY/dCoMwDIXv9xSlhamQ5QEGnQ8iXlSoUHCjtGX4@@zOFB2bgrlo0sM5H0kt59ujAj8USnp8Kpte706/tfM6Aw8e1w@obSpRvbp8GMNYYW9sGjJUTbMIHbRjJ2WLwaW5gIQlGTofnLHTNM2VCZpJVnBEDhx5ebGm71WUBBWpW6eBHKwuKAfRWl52jH8IUuob3mBnkMXE4sP265AqcKWcMiLgcBCKuOHPWUfI/AE "Ruby – TIO Nexus")
Saved 2 bytes by moving the assignment to the first use of a.
Apparently Ruby is smart enough to not confuse the commas in the array definition and commas that would arise from simultaneous variable assignment (at least in this case :D)
[Answer]
# [Python 2](https://docs.python.org/2/), 134 bytes
```
b,s=input()
a=[''.join(l[::-1])for l in s]
print any(b==[l.replace('#',' ').rstrip()for l in x][:len(b)]for x in(a,a[::-1],s[::-1],s))
```
Takes input as two lists of strings (one for each line). Assumes no trailing whitespace on the lines.
[Try it online!](https://tio.run/nexus/python2#VY@xbsQgDIbn4ymsZDBIFOlWpIzXtQ@AGAilKhUiCKiae/oUkstVZbDNz8dv2y7vbhqGYZt5mXxM35UyYiaFKL4WH2lQUr5cNftYMgTwEYomKftYwcQ7nadJBZFdCsY6iiNyBGQil5p9on@fVq1kcJHOTHdtbRo13BzevJyZsa2NQmq@S3L5@fTBwbVVF7c6S22blBG3Wpcq3N5ebzkvWUIypWwKhWi9BWqucOyn387cC9TkhA5KdPn5etKd6kv8dxofzPhkYHfaIzwMG7TbHD0a9gs "Python 2 – TIO Nexus")
**Examples:**
```
Input: ['..','.'],['#####','.####','..###'] (example 1)
>True
Input: ['..','..'],['...##','..###','.####'] (example 2)
>False
Input: ['',' .'],['#####','#.###','#####'] (no bite in top row)
>True
```
[Answer]
## Python 2, 173 bytes
[Try it online](https://tio.run/nexus/python2#VY0/C4MwEMX3fIqDDsnVKO0qzeLspONxQ4ItCDYVsRA/vTXGDg735/fu8W5ttTO9H7@zQlGb4elFZd52VIN9u85CKGl5yEJa38mL/EywwGvvvYfAGW0iX1WtWrox5rUKiNplRJzUKDlEFM05NFBZ5nfWFYpx6v0MrTEVbMFxpluC5gTrSvGj3quQrOnYovKnVLwhHR5Ibv4B)
```
S,b=input()
L=len
B=map(lambda x:[y<'.'and'#'or y for y in x]+['#']*(L(S[0])-L(x)),b+[[]]*(L(S)-L(b)))
R=map(lambda x:x[::-1],B)
print S==B or S==B[::-1]or S==R[::-1]or S==R
```
Takes input as two lists of lists of characters.
First - sandwich
Second - bite
First it extends bite array to the size of sandwich array:
```
B=map(lambda x:[y<'.'and'#'or y for y in x]+['#']*(L(S[0])-L(x)),b+[[]]*(L(S)-L(b)))
```
`[y<'.'and'#'or y for y in x]` replaces all spaces to `#`
`(L(S[0])-L(x)),b+[[]]*(L(S)-L(b))` calculates the number of missing element
Then it compares all 4 rotation of this "extended" bite to the sandwich:
```
R=lambda:map(lambda x:x[::-1],B)
print S==B or S==B[::-1]or S==R()or S==R()[::-1]
print any(map(S.__eq__,[B,B[::-1],R(),R()[::-1]])) #longer but pretty
```
lambda R is used to mirror list of lists horizontally
In the linked example sandwich is:
```
##.
#.#
###
```
And bite is:
```
.
.
```
] |
[Question]
[
The user will hide, and the computer will try to find them.
First, the program will take an input, for the size of the grid. Like 5x5, 10x10, 15x15, etc. The grid won't always be a perfect square.
The grid is sort of like a chessboard:
```
_______________________________
| | | | | |
| A1 | | | | | A
|_____|_____|_____|_____|_____|
| | | | | |
| | B2 | | | | B
|_____|_____|_____|_____|_____|
| | | | | |
| | | C3 | | | C
|_____|_____|_____|_____|_____|
| | | | | |
| | | | D4 | | D
|_____|_____|_____|_____|_____|
| | | | | |
| | | | | E5 | E
|_____|_____|_____|_____|_____|
1 2 3 4 5
```
Now, the user will pick a square, such as `B2` (without telling the computer)
The computer will start guessing squares. If it picks the correct square, the user will respond with `y`. If not, they will input the direction their tile is from the one picked (N, NE, E, SE, S, SW, W).
So if the user picked `B2`, and the computer guessed `C3`, the user would input `NW`.
Here is an example of the outputs and inputs:
```
Grid?
5x5
C3?
NW
C2?
N
B2?
y
```
# Scoring:
This will be scored a little differently than a normal challenge.
The winner is the program that takes lowest number of guesses (on average) it takes to guess the correct square. The test cases to be averaged will be all of the possible squares in a 5x5 and then in a 10x10.
However, it must also work with every pattern of grid up to 26 rows (i.e. 5x8, 6x2, 20x5, etc.).
Please include a way for it to be tested, such as a JSFiddle.
And lastly, in case of a tie, the shortest program wins.
[Answer]
# [Python 3.6](https://docs.python.org/3.6/), ~~466~~ ~~398~~ 392 bytes, minimax
```
x, y = 1, 1
w, h = [int(x) for x in input('Grid?\n').split('x')]
def split_factor(a, b):
N = b-y
W = a-x
S = h+~N
E = w+~W
return max(1, N, W, S, E, N*W, S*W, S*E, N*E)
def move(a, b):
*Z, = zip([a, x, a, a+1, x, x, a+1, a+1],
[y, b, b+1, b, y, b+1, b+1, y],
[1, a-x, 1, w+x+~a, a-x, a-x, w+x+~a, w+x+~a],
[b-y, 1, h+y+~b, 1, b-y, h+y+~b, h+y+~b, b-y])
return Z[['N', 'W', 'S', 'E', 'NW', 'SW', 'SE', 'NE'].index(d)]
d = ''
while d != 'y':
print()
splits = {(a, b): split_factor(a, b) for a in range(x, x+w) for b in range(y, y+h)}
a, b = min(splits, key=splits.get)
d = input(f'{a}{"ABCDEFGHIJKLMNOPQRSTUVWXYZ"[b]}?\n')
x, y, w, h = move(a, b)
```
Input and output should be in the form shown in the example. This finds the square with the minimal "split factor"--which is the largest remaining area that can result from the player's answer (i.e. NW, E, y, etc.)--and guesses that. Yes, that's always the center of the remaining area in this game, but [this technique](https://en.wikipedia.org/wiki/Minimax) of minimizing the worst-case will work more generally in similar games with different rules.
Unreadable version:
```
x=y=d=1
w,h=map(int,input('Grid?\n').split('x'))
while d!='y':print();s={(a,b):max(b-y,h+y+~b)*max(w+x+~a,a-x)for a in range(x,x+w)for b in range(y,y+h)};a,b=min(s,key=s.get);d=input(f'{a}{chr(64+b)}?\n');*z,=zip([a+1,x,a+1,x,a,a,a+1,x],[b+1,b+1,y,y,b+1,y,b,b],[w+x+~a,a-x,w+x+~a,a-x,1,1,w+x+~a,a-x],[h+y+~b,h+y+~b,b-y,b-y,h+y+~b,b-y,1,1]);x,y,w,h=z[~'WENS'.find(d)or-'NWNESWSE'.find(d)//2-5]
```
[Answer]
# Mathematica, optimal behavior on test cases, 260 bytes
```
For[a=f=1;{c,h}=Input@Grid;z=Characters;t=<|Thread[z@#->#2]|>&;r="";v=Floor[+##/2]&;b:=a~v~c;g:=f~v~h,r!="y",r=Input[g Alphabet[][[b]]];{{a,c},{f,h}}={t["NSu",{{a,b-1},{b+1,c},{b,b}}]@#,t["uWX",{{g,g},{f,g-1},{g+1,h}}]@#2}&@@Sort[z@r/.{c_}:>{c,"u"}/."E"->"X"]]
```
This program can be tested by cutting and pasting the above code into the [Wolfram Cloud](http://sandbox.open.wolframcloud.com). (Test quickly, though: I think there's a time limit for each program run.) The program's guesses look like `2 c` instead of `C2`, but otherwise it runs according to the spec above. The grid must be input as an ordered pair of integers, like `{26,100}`, and responses to the program's guesses must be input as strings, like `"NE"` or `"y"`.
The program keeps track of the smallest and largest row number and column number that is consistent with the inputs so far, and always guesses the center point of the subgrid of possibilities (rounding NW). The program is deterministic, so it's easy to compute the number of guesses it requires on average over a fixed grid. On a 10x10 grid, the program requires 1 guess for a single square, 2 guesses for eight squares, 3 guesses for 64 squares, and 4 guesses for the remaining 27 squares, for an average of 3.17; and this is the theoretical minimum, given how many 1-guess, 2-guess, etc. sequences can lead to correct guesses. Indeed, the program should achieve the theoretical minimum on any size grid for similar reasons. (On a 5x5 grid, the average number of guesses is 2.6.)
A little code explanation, although it's fairly straightforward other than the golfingness. (I exchanged the order of some initializing statements for expository purposes—no effect on byte count.)
```
1 For[a = f = 1; z = Characters; t = <|Thread[z@# -> #2]|> &;
2 v = Floor[+##/2] &; b := a~v~c; g := f~v~h;
3 r = ""; {c, h} = Input@Grid,
4 r != "y",
5 r = Input[g Alphabet[][[b]]];
6 {{a, c}, {f, h}} = {t["NSu", {{a, b - 1}, {b + 1, c}, {b, b}}]@#,
7 t["uWX", {{g, g}, {f, g - 1}, {g + 1, h}}]@#2} & @@
8 Sort[z@r /. {c_} :> {c, "u"} /. "E" -> "X"]
]
```
Lines 1-3 initialize the `For` loop, which actually is just a `While` loop in disguise, so hey, two fewer bytes. The possible row-number and column-number ranges at any moment is stored in `{{a, c}, {f, h}}`, and the centered guess in that subgrid is computed by the functions `{b, g}` defined in line 2. Line 3 initializes the max-row `c` and max-column `h` from user input, and also initializes `r` which is the loop-tested variable and also the subsequent user inputs.
While the test on line 4 is satisfied, line 5 gets input from the user, where the prompt comes from the current guess `{b, g}` (`Alphabet[][[b]]]` converts the row number to a letter). Then lines 6-8 update the subgrid-of-possibilities (and hence implicitly the next guess). For example, `t["NSu", {{a, b - 1}, {b + 1, c}, {b, b}}]` (given the definition of `t` on line 1) expands to
```
<| "N" -> {a, b - 1}, "S" -> {b + 1, c}, "u" -> {b, b}|>
```
where you can see the min-row and max-row numbers being updated according to the user's last input. Line 8 converts any possible input to an ordered pair of characters of the form `{ "N" | "S" | "u", "u" | "W" | "X"}`; here `"u"` stands for a correct row or column, and `"X"` stands for East (just to allow `Sort` to work nicely). When the user finally inputs `"y"`, these lines throw an error, but then the loop-test fails and the error is never propogated (the program simply halts anyway).
[Answer]
## Batch, divide-and-conquer
```
@echo off
set z = ABCDEFGHIJKLMNOPQRSTUVWXYZ
set /p g = Grid?
set /a w = 0, n = 0, e = %g :x= + 1, s = % + 1
:l
set /a x = (w + e) / 2, y = (n + s) / 2
call set c = %%z :~%y%,1%%
set /p g = %c %%x%?
if %g :w=.% == %g % set /a w = x
if %g :n=.% == %g % set /a n = y
if %g :e=.% == %g % set /a e = x
if %g :s=.% == %g % set /a s = y
if %g :y=.% == %g % goto l
```
Works by creating the bounding box of the the area still to be searched. The next guess is always the centre of the box. For those compass points that are not included in the response, the box is reduced in that direction. For example for a response of `N`, the left, right and bottom of the box are set to the guessed square.
At 369 bytes I'm not expecting to beat anybody so I've left the spaces in for readibility.
] |
[Question]
[
We are putting balls into a fixed number **a** bins. These bins begin empty.
```
Empty bin (a=4): 0 0 0 0
```
And one by one we add balls to the bins.
```
0 0 0 1 or
0 0 1 0 or
0 1 0 0 or
1 0 0 0
```
We need a quick way to loop over all the possible states the bins take, without duplicates and without missing any and we don't want to enumerate all the possible bins. So instead we assign each bin-configuration an index.
We assign the index by sorting the possible configurations in a specific way:
1. Sort ascending by sum: so first `0 0 0 0`, then the possible configurations with 1 ball added, then 2, etc.
2. Then sort within each sum in ascending order, from the first bin to the last:
```
0 0 0 2
0 0 1 1
0 0 2 0
0 1 0 1
0 1 1 0
0 2 0 0
etc
```
3. The index is then assigned ascending through this list:
```
0 0 0 0 -> 1
0 0 0 1 -> 2
0 0 1 0 -> 3
0 1 0 0 -> 4
1 0 0 0 -> 5
0 0 0 2 -> 6
0 0 1 1 -> 7
0 0 2 0 -> 8
0 1 0 1 -> 9
0 1 1 0 -> 10
0 2 0 0 -> 11
```
## Rules
Create a function or program that takes a list of any size with non-negative integers and print or output its index. You can assume **a** to be at least 2. Shortest code wins. You may use 0-indexed output or 1-indexed, but specify which you use. NB: all examples here are 1-indexed.
## Example code
Not golfed, in R:
```
nodetoindex <- function(node){
a <- length(node)
t <- sum(node)
if(t == 0) return(1)
index <- choose(t-1 + a, a)
while(sum(node) != 0){
x <- node[1]
sumrest <- sum(node)
if(x == 0){
node <- node[-1]
next
}
a <- length(node[-1])
index <- index + choose(sumrest + a, a) - choose(sumrest - x + a, a)
node <- node[-1]
}
return(index + 1)
}
```
## Test cases
```
10 10 10 10 -> 130571
3 1 4 1 5 9 -> 424407
2 9 -> 69
0 0 0 -> 1
0 0 1 -> 2
0 0 0 0 0 0 -> 1
1 0 0 0 0 1 -> 23
```
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), 8 bytes
```
S0rṗLSÞi
```
[Try it online!](https://tio.run/nexus/jelly#@x9sUPRw53Sf4MPzMv9XPWrcFmWtdLj9UdMa9///o410FCxjdRSiDXQUQAjBNEQShSOQmCGqmGEsAA "Jelly – TIO Nexus")
Brute-force solution. The first test case is too much for TIO, but I've verified it locally on my laptop. The second test case requires too much RAM, even for my desktop computer.
### How it works
```
S0rṗLSÞi Main link. Argument: A (array)
S Compute the sum s of A.
0r Create the range [0, ..., s].
L Yield the length l of A.
ṗ Cartesian power; yield the array of all l-tuples over [0, ..., s], in
lexicographical order.
SÞ Sort the l-tuples by their sums. The sorting mechanism is stable, so
l-tuples with the same sum are still ordered lexicographically.
i Find the index of A in the generated array of tuples.
```
[Answer]
## Clojure, 152 bytes
```
#(loop[v[(vec(repeat(count %)0))]i 1](if-let[r((zipmap v(range))%)](+ r i)(recur(sort(set(for[v v i(range(count v))](update v i inc))))(+ i(count v)))))
```
Not as easy as I thought. Less golfed version:
```
(def f (fn[t](loop[v[(vec(repeat(count t)0))]i 1]
(if-let[r((zipmap v(range))t)](+ r i)
(recur (sort-by (fn[v][(apply + v)v]) (set(for[v v i(range(count v))](update v i inc))))
(+ i(count v)))))))
```
Loops over current states `v`, creates a hash-map from elements of `v` to their rank, if the searched state is found then its rank is returned (+ the number of previously seen states). If not found then recurses with a new set of possible states.
Oh actually we don't need that custom sorting function as all states within each loop has identical sum. This isn't as slow as I expected as `[3 1 4 1 5 9]` took only 2.6 seconds.
[Answer]
# Mathematica, 50 bytes
A port of [Dennis's Jelly answer](https://codegolf.stackexchange.com/a/102381/56178).
```
0~Range~Tr@#~Tuples~Length@#~SortBy~Tr~Position~#&
```
Unnamed function taking a list of integers as input, and returning a depth-2 list with a single integer as output; for example, the input for the last test case is `{1,0,0,0,0,1}` and the output is `{{23}}`.
A slightly ungolfed version is:
```
Position[SortBy[Tuples[Range[0,Tr[#]],Length[#]],Tr],#]&
```
Often we can save individual bytes in Mathematica by using prefix notation (`function@n` instead of `function[n]`) and infix notation (`a~function~b` instead of `function[a,b]`). This only works, however, when the resulting code happens to mesh well with Mathematica's intrinsic precedence order for applying functions. I was kind of amazed here that, with six sets of square brackets, it actually worked to remove *all* of them and save six bytes with the (pleasantly bracketless) submitted code.
] |
[Question]
[
Output a full formal poof of such statements such as `1+2=3`, `2+2=2*(1+1)` etc.
# Introuction
If you know Peano Arithmetic you can probably skip this section.
Here's how we define the Natural Numbers:
```
(Axiom 1) 0 is a number
(Axiom 2) If `x` is a number, the `S(x)`, the successor of `x`, is a number.
```
Hence, for example `S(S(S(0)))` is a number.
You can use any equivalent representation in your code. For example, all of these are valid:
```
0 "" 0 () !
1 "#" S(0) (()) !'
2 "##" S(S(0)) ((())) !''
3 "###" S(S(S(0))) (((()))) !'''
...
etc
```
We can extend the rules to define addition as follows.
```
(Rule 1) X+0 = X
(Rule 2) X+S(Y)=S(X)+Y
```
With this we can prove 2+2=4 as follows
```
S(S(0)) + S(S(0)) = 2 + 2
[Rule 2 with X=S(S(0)), Y=S(0)]
S(S(S(0))) + S(0) = 3 + 1
[Rule 2 with X=S(S(S(0))), Y=0]
S(S(S(S(0)))) + 0 = 4 + 0
[Rule 1 with X=S(S(S(S(0))))
S(S(S(S(0)))) = 4
```
We can extend these rules to define multiplication as follows
```
(Rule 3) X*0 = 0
(Rule 4) X*S(Y) = (X*Y) + X
```
Although to allow this we need to define the structural role of parentheses.
```
(Axiom 3) If X is a number, (X) is the same number.
```
Addition and multiplication operators are strictly binary and parentheses must always be explicit. `A+B+C` is not well-defined, but `(A+B)+C` and `A+(B+C)` are.
# Example
Now we have enough to prove a theorem about multiplication: 2+2=2\*2
```
2 + 2
(2) + 2
(0 + 2) + 2
((0*2) + 2) + 2
(1*2) + 2
2*2
```
# Requirements
A *proof that `A=B`* is a list expressions such that:
* the first is `A`,
* the last is `B`, and
* each expression in the list apart from the first can obtained from the previous by transforming it under one of the rules.
Your program will take **two valid expressions as input**, each expression contains numbers, addition, multiplication, and parentheses as defined above.
Your program will output a proof, a list as defined above, that the two expressions are equal, if such a proof exists.
If the two expressions are not equal, your program will output nothing.
Proving or disproving is always possible in a finite number of steps, because each expression can be reduced to a single number and these numbers can be trivially tested for equality.
If the input expressions are not valid (e.g. unbalanced parentheses, contains non-numbers, or non-binary operators) then your program should exit with error, throw an exception, print an error, or otherwise produce some observable behaviour *which is distinct from the case in which the inputs are valid but non-equal*.
In summary, the normal output for admissible inputs is a list of equal numbers, including the inputs, which is produced by the following rules.
```
(Axiom 1) 0 is a number
(Axiom 2) If `x` is a number, the `S(x)`, the successor of `x`, is a number.
(Axiom 3) If X is a number, (X) is the same number
(Rule 1) X+0 = X
(Rule 2) X+S(Y)=S(X)+Y
(Rule 3) X*0 = 0
(Rule 4) X*S(Y) = (X*Y) + X
(Rule 5) X = (X) (Axiom 3 expressed as a transformation rule.)
```
Any suitable representation of the numbers in the input and output is allowed, e.g. `0=""=()`, `3="###"=(((())))`, etc. Whitespace is irrelevant.
Rules can, of course, be applied in either direction. Your program does not have to output which rule is used, just the expression produced by its action on the previous expression.
Shortest code wins.
[Answer]
# Perl, 166 + 1 bytes
Run with `-p` (1 byte penalty).
```
$r='\((S*)';(@b,@a)=@a;push@a,$_ while+s/\+S/S+/||s/$r\+\)/$1/||s/$r\*\)//||s/$r\*S(S*)/(($1*$2)+$1/||s/$r\)/$1/;$\.=/[^S]./s;$_=$b[-1]eq$a[-1]?join'',@b,reverse@a:""
```
More readable:
```
# implicit: read a line of input into $_
# we leave the newline on
$r = '\((S*)'; # we use this regex fragment a lot, factor it out
(@b, @a) = @a; # set @b to @a, @a to empty
push @a, $_ while # each time round the loop, append $_ to @a
+s/\+S/S+/|| # rule 2: change "+S" to "S+"
s/$r\+\)/$1/|| # rule 1: change "(X+0)" to "X"
s/$r\*\)//|| # rule 3: change "(X*0)" to ""
s/$r\*S(S*)/(($1*$2)+$1/|| # rule 4: change "(X*Y" to "((X*Y)+X"
s/$r\)/$1/; # rule 5: change "(X) to "X"
$\.=/[^S]./s; # append a 1 to the newline character if we
# see any non-S followed by anything
$_=$b[-1]eq$a[-1]? # if @b and @a end the same way
join'',@b,reverse@a # then $_ becomes @b followed by (@a backwards)
:"" # otherwise empty $_
# implicit: output $_
```
The input format expresses numbers in unary as strings of `S`, and requires the two inputs on separate lines (each followed by a newline, and an EOF after both are seen). I interpreted the question as requiring that parentheses should be literally `(` `)` and addition/multiplication should be literally `+` `*`; I can save a few bytes through less escaping if I'm allowed to make different choices.
The algorithm actually compares the first line of input with an empty line, the second with the first, the third with the second, and so on. This fulfils the requirements of the question. Here's an example run:
My input:
```
(SS+SS)
(SS*SS)
```
Program output:
```
(SSS+S)
(SSSS+)
SSSS
SSSS
(SSSS+)
((SS+)SS+)
(((SS*)SS+)SS+)
(((SS*)S+S)SS+)
(((SS*)+SS)SS+)
((SS*S)SS+)
((SS*S)S+S)
((SS*S)+SS)
```
The duplicated `SSSS` in the middle is annoying but I decided it didn't violate the specification, and it's fewer bytes to leave it in.
On invalid input, I append `1` to the newline character, so you get stray `1`s sprinkled in at the end of the output.
] |
[Question]
[
Mr Short likes to play chess. Mr Short is also a very traditional man. Hence, Mr Short is disturbed by the recent trend of using [Algebraic notation](https://en.wikipedia.org/wiki/Algebraic_notation_(chess)) in modern chess, and he would rather use [Descriptive notation](https://en.wikipedia.org/wiki/Descriptive_notation), like his father and his father's father before him.
# Note
To simplify this challenge, I chose not to deal with disambiguaties (as in, when two pieces can move to the same square, or can capture the same piece.) Also there is no dealing with en passant, promotion, or Castling.
# Algebraic notation for the uninitiated
* The board squares are numbered from `a1` at the bottom left to `h8` as the top right. The letters represent the files (columns) while the numbers represent the ranks (rows). The white King is placed in the beginning of the game at the square `e1`.
* A move consists of the piece that moved + the destination square. For example, a King moving to `e2` would be `Ke2`.
* If the piece that had moved is a Pawn, the piece letter is omitted. For example, the starting move Pawn to `e4` is written as `e4`.
* If the move is a capture, then the `x` letter is inserted between the piece and the destination square. For example, a Queen capturing at `f7` is annotated as `Qxf7`.
* If the capturing piece is a Pawn, since it moves diagonally, the notation records the file the Pawn originated from. For example, when the Pawn at `c4` captures a piece at `d5`, the move is annotated as `cxd5`.
* Piece symbols are `K` for King, `Q` for Queen, `B` for Bishop, `N` for Knight, and `R` for Rook. Pawns have no symbols.
* Other annotations include `+` for check, and `#` for checkmate. A Pawn moving to f7 and giving check is `f7+`. Note lack of space.
# Descriptive notation for the uninitiated
* The files are described by the piece that starts on it. For example, what would be the `e` file in Algebraic, becomes the King file, or, for short, `K`. The other files are marked by their side, then the piece. So file `h` is the King's Rook's file, or `KR`.
* The ranks are numbered from the point of view of the moving player. What would be the fourth rank in Algebraic, is the fourth rank for white, but the *fifth* rank for black.
* It follows that the square `e4` is `K4` for the white player and `K5` for the black player. The square `f7` is `KB7` for the white player and `KB2` for the black player.
* A move is annotated by the piece moving, then a dash, then the target square. So a Pawn moving to `K4` is `P-K4`. A Queen moving to `KR5` is `Q-KR5`.
* A capture is annotated by the capturing piece, then `x`, then the captured piece. Therefore a Bishop capturing a Pawn is `BxP`. **Usually you need to mark *which* Pawn is being captured, but ignore this for sake of simplicity.**
* Piece symbols are `K` for King, `Q` for Queen, `B` for Bishop, `Kt` for Knight (note the different symbol), `R` for Rook, and `P` for Pawn.
* Other annotations include `ch` for check and `mate` for checkmate. A Pawn moving to `KB7` and giving check is `P-KB7 ch`. Note the space.
# Input
A string of algebraic notation moves, delineated by spaces. There are no move numbers. For example, the [Fool's mate](https://en.wikipedia.org/wiki/Fool%27s_mate) goes like this:
```
f3 e5 g4 Qh4#
```
Or the game Teed vs Delmar, from the same Wikipedia page:
```
d4 f5 Bg5 h6 Bf4 g5 Bg3 f4 e3 h5 Bd3 Rh6 Qxh5+ Rxh5 Bg6#
```
The [Immortal game](https://en.wikipedia.org/wiki/Immortal_Game).
```
e4 e5 f4 exf4 Bc4 Qh4+ Kf1 b5 Bxb5 Nf6 Nf3 Qh6 d3 Nh5 Nh4 Qg5 Nf5 c6 g4 Nf6 Rg1 cxb5 h4 Qg6 h5 Qg5 Qf3 Ng8 Bxf4 Qf6 Nc3 Bc5 Nd5 Qxb2 Bd6 Bxg1 e5 Qxa1+ Ke2 Na6 Nxg7+ Kd8 Qf6+ Nxf6 Be7#
```
You may assume that input is always a valid game. All moves are in the correct order, and no extraneous data is present. **No moves will include disambiguation**.
For example, [The Evergreen game](https://en.wikipedia.org/wiki/Evergreen_Game) despite being, obviously, a valid game, is not going to be input due to the 19th move, `Rad1`.
You may also assume that all input move lists start from the starting position.
# Output
A move list, with a similar format, in Descriptive notation.
For example, the Fool's mate:
```
P-KB3 P-K4 P-KKt4 Q-KR5 mate
```
Teed vs Delmar:
```
P-Q4 P-KB4 B-KKt5 P-KR3 B-KB4 P-KKt4 B-KKt3 P-KB5 P-K3 P-KR4 B-Q3 R-KR3 QxP ch RxQ B-KKt6 mate
```
The Immortal Game:
```
P-K4 P-K4 P-KB4 PxP B-QB4 Q-KR5 ch K-KB1 P-QKt4 BxP Kt-KB3 Kt-KB3 Q-KR3 P-Q3 Kt-KR4 Kt-KR4 Q-KKt4 Kt-KB5 P-QB3 P-KKt4 Kt-KB4 R-KKt1 PxB P-KR4 Q-KKt3 P-KR5 Q-KKt4 Q-KB3 Kt-KKt1 BxP Q-KB3 Kt-QB3 B-QB4 Kt-Q5 QxP B-Q6 BxR P-K5 QxR ch K-K2 Kt-QR3 KtxP ch K-Q1 Q-KB6 ch KtxQ B-K7 mate
```
This is not the simplest Descriptive notation possible, since sometimes you don't need to specify which Knight file was moved to (as in, `Q-KKt4` could be written as `Q-Kt4` since the move `Q-QKt4` is impossible.) The move `BxP` is ambiguous (which pawn: should be `BxQKtP`), but Mr Short doesn't care about that too much.
You may consider these your test cases.
Note: I wrote these by hand. If you catch any glaring mistakes, please let me know.
# Rules and Scoring
* Standard rules apply : program with output to stdout, or function. Nothing to stderr. Standard loopholes are forbidden.
* Please link to a site where we can test your code.
* Code golf: shortest code wins.
# In Conclusion
This is my first challenge, so I *probably* made some noobish errors. Feedback on the question (in the comments, obviously) is appreciated.
[Answer]
## Batch, 588 bytes
```
@echo off
for %%r in (a.R b.Kt c.B d.Q e.K f.B g.Kt h.R)do set %%~nr1=%%~xr&set %%~nr8=%%~xr
for %%r in (a b c d e f g h)do set %%r2=.P&set %%r7=.P
set s=
set a=
:l
set m=%1
set c=
for %%r in (ch.+ mate.#) do if .%m:~-1%==%%~xr set c= %%~nr&set m=%m:~,-1%
set/ab=(a^^%m:~-1%-1)+1,a=7-a
set p=%m:~0,1%
for %%r in (a b c d e f g h)do if %p%==%%r set p=P
for %%r in (QR.a QKt.b QB.c Q.d K.e KB.f KKt.g KR.h)do if .%m:~-2,1%==%%~xr set d=-%%~nr%b%
if %m:~-3,1%==x call set d=x%%%m:~-2%:~1%%
set %m:~-2%=.%p:N=Kt%
set s=%s% %p:N=Kt%%d%%c%
shift
if not "%1"=="" goto l
echo%s%
```
`s` is the output string. `m` is the current move (moves are taken as command-line parameters). `a` is the current player (0 for White, 7 for Black). `b` is the row as seen from the point of view of the current player. `c` is the `ch` or `mate` flag. `p` is the current piece. If there is no piece (i.e. a lowercase letter `a-h`) then `P` is substituted. (The `N` to `Kt` substitution is done later to save bytes.) The destination column is then looked up in a dictionary. However if the move is actually a capture then the destination becomes an `x` followed by the piece previously on that square. Either way the destination square is then set to the piece that just moved there. The moves are accumulated until there are no more parameters and then they are printed.
The variables `a1`...`h8` are used to store the last seen piece. The `.` prefix is there because of the way I initialise the back row; it's hard to loop over two variables at once in Batch unless I'm allowed to begin one with a `.`.
[Answer]
# [JavaScript (Node.js)](https://nodejs.org), 473 bytes
```
(n,c=(X=>[...'abcdefgh'].map(a=>[...'12345678'].map(b=>X[a+b]=a<'c'|a>'f'?a<'b'|a>'g'?['R','Kt',...'BQKB','Kt','R'][--b]:'P':''))&&X)({}),g=s=>s?s=='N'?'Kt':s:'P')=>n.split` `.map((e,i)=>(Q=c[S=e.slice(I=e.search(/[a-h](?!x)/),I+2)],((c[S]=g(e.split(/[a-hx]/)[0]))+(e[Z='includes']`x`?'x'+Q:'-'+((S=e[I])>'d'?'K'+['','B','Kt','R']['efgh'.indexOf(S)]:'Q'+['R','Kt','B','']['abcd'.indexOf(S)])+((Y=e[e.search(/\d/)])&&i%2?9-Y:Y))))+(e[Z]`#`?' mate':e[Z]`+`?' ch':'')).join` `
```
[Try it online!](https://tio.run/##VVDbbtswDP0VrcVCCb5kSRwnMyYb8FsQIJ3bl2SeAMuyfClcJ6jTwcC2b08pJ8PQBxHi4Tk8JJ/lL9mr1@Z0drpjoS8lv9DOVpzueZi6rgsyV4UuqxqE@yJPVN7g2XzhLf3V@gbnPNyn0soFl99AwR8ZQgkR/vPxX0GUwiPYsD2DbeRxso1vKeIidZxcBPAdAgDGJpM9o7//MrviPQ/7qOccdhAZdtAbFuNh5/antjlnJBv9qbYbRGnCVfrEtdu3jdJ0Y35avqqaTlPp1IJGnwY2ZfbGmjNhU4pkwSuqr82upEFMWfpFMGZRnf7g0HSqfSt0DyIbsggGsJIAHLAoRaN0I1gIhRkOrBRwmw9rwXg5t@kKPTyU9Inhkokh/rvFSDdEc@YPRLSnBzT4v8HPYorwZNJ8nkdfnUNwYOw2pMjucTLyIs8agjG3TK7q6z3d52PT4aUu6tj1x1a77bGiJb3THtFLUmIcMMTKI0ntWWRbzki@JPGAYVf6@BZY8EmxILsaoRp5lSktifJJ5Y2kx2pGlFGMVZ8g0ZAS1O6qNTZDh8Q0Uwt0QnWBxSGfk7jwsYpqbQA5Q389JzuJ1KFaYVasjdDCFOWxXt3fMXZ5Bw "JavaScript (Node.js) – Try It Online")
Output is different to the testcase, but it seems like there is an error the OP made. Only 1 mistake, though.
## How
Quite simple for such a long program. Creates an object, `c`, which stores the position of every piece. Handling captures is simple, simply overwrite the square. Inside the `map` function, we assign `Q` to the target square's piece before overwriting, then refer to it when a capture is seen. If not a capture, then index into an array to find the correct file (correct me if "file" is not the right term as I'm no expert in chess) and determine the number (9-Y if black turn, Y if white term). Also a few simple invocations of `includes` and a few extra ternaries add the `ch`s and `mate`s at the end.
] |
[Question]
[
**A Latin square is a square that has no repeated symbols in either the X or Y columns**. For example:
```
ABCD
DABC
CDAB
BCDA
```
is one such square. Notice how every column and row contains a permutation of the same 4 letters.
However, our Latin square has a problem: **If I were to rotate the second row (`DABC`) 1 to the left, I'd end up with `ABCD`, which is identical to the permutation above it.** If it is *impossible* to rotate any 1 column/row and obtain another column/row, then we consider the square to be **rotation safe**.
For example:
```
ABCD
BDAC
CADB
DCBA
```
is rotation safe. The grid has the following properties:
1. **Point [0,N] uses the Nth symbol**
2. **Point [0,N] and [N,0] are always the same symbol**. (I'd like to also say that [x,y] and [y,x] are also always the same letter, but I can't prove it)
**Your task is to print out 1 rotation-safe Latin square, when passed N.** I don't care if you output letters, numbers, a list, or a 2D array. **If you use numbers, the top column and row must be `0,1,2,3,...` (in that order). If you use letters, then it must be `A,B,C,D,....`**
For example, if your input was 4, you should either print:
```
0,1,2,3 0,1,2,3
1,3,0,2 or 1,0,3,2
2,0,3,1 2,3,1,0
3,2,1,0 3,2,0,1
```
There are no rotation-safe Latin squares of size less than 4. I don't care what your program does if N is less than 4. For the curious, the number of rotation-safe squares is (starting at 4): `2,5,5906,(too long to calculate)`
This is a [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so try to make answers as short as possible in your favorite language!
[Answer]
# Pyth - 29 bytes
Brute force.
```
hf&!@JsCBTsm.>RdJStQ.A{IMJ^.p
```
Does not finish online even for `n=4`, but you can try it out locally, or [run this modified version online for one more byte](http://pyth.herokuapp.com/?code=hf%26.A%7BIMCT%21%40JsCBTsm.%3ERdJStQ%5E.p&input=4&debug=0).
[Answer]
# Sqlserver 2012 - 918 bytes
On my box this runs for @k = 5, although it takes 16 seconds.
This is code building code(watch out Skynet, you have competition)
Is there a price for the longest script?
```
DECLARE @k int = 4;
DECLARE @t VARCHAR(max)='WITH C as(SELECT
top '+left(@k,1)+'row_number()over(order by 1/0)n
FROM sys.messages),D(nÆ)as(SELECT
concat(~),~
FROM Ø
WHERE |)SELECT top 1~ FROM Å
WHERE 1=1',@
varchar(999)=''SELECT @+=','+CHAR(x+65)FROM(values(0),(1),(2),(3),(4),(5))x(x)WHERE x<@k
SELECT
@t=REPLACE(REPLACE(REPLACE(REPLACE(@t,'Æ',@),'Ø',STUFF(REPLACE(@,',',',C '),1,1,'')),'Å',STUFF(REPLACE(@,',',',D
'),1,1,'')),'~',STUFF(REPLACE(@,',','.n,'),1,3,'')+'.n'),@='';WITH C as(SELECT top(@k)x
FROM(values(0),(1),(2),(3),(4),(5))x(x))SELECT @+=' AND
'+char(65+C.x)+'.n<>'+char(65+D.x)+'.n'FROM c,c d WHERE C.x<D.x
SELECT @t=REPLACE(@t,'|',STUFF(@,1,4,''));WITH A
as(SELECT top(@k)x
FROM(values(65),(66),(67),(68),(69),(70))x(x))SELECT @t+='AND
'+char(A.x)+'.'+char(C.x)+'<>'+CHAR(B.x)+'.'+char(C.x)+' AND
'+char(A.x)+'.n+'+char(A.x)+'.n'+'
not like''%''+'+char(B.x)+'.n+''%'''FROM A,A B,A C
WHERE A.x<>B.x and C.x<>B.x
EXEC(@t)
```
[Try online!](https://data.stackexchange.com/stackoverflow/query/485215/rotation-safe-latin-squares)
] |
[Question]
[
[Subleq](https://esolangs.org/wiki/Subleq) is a programming language with **only one** instruction. Each instruction contains 3 parameters. Code and data space is the same. How it works:
```
A B C
```
A, B and C are signed ints. Instructions are executed in the next way:
```
*B = *B - *A
if(*B <= 0) goto C;
```
One post is one tip. Write your tips for Subleq here!
[Online interpreter, assembler and C to Subleq converter](http://mazonka.com/subleq/online/hsqjs.cgi)
[Answer]
# Third Argument in Output Command is Extra Memory
Subleq specifies output with the three word command `x -1 y`, where x is the address of the value to be output. Unlike other Subleq commands, execution will proceed to the next command in all cases and `y` is ignored. This means it is available to be used for memory.
For example `0:2 -1 65` will print the "A" (CHAR(65)) stored in 2: and then proceed to 3:.
] |
[Question]
[
**Closed**. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Add details and clarify the problem by [editing this post](/posts/54877/edit).
Closed 8 years ago.
[Improve this question](/posts/54877/edit)
## Challenge:
Your challenge (should you choose to accept it) is to compress and decompress the 5MB "*Complete Works of William Shakespeare*" as found here:
<http://www.gutenberg.org/cache/epub/100/pg100.txt>
(MD5: `a810f89e9f8e213aebd06b9f8c5157d8`)
## Rules:
* You **must** take input via `STDIN` and output via `STDOUT`...
* ...and you **must** provide an identical decompressed result to the input.
+ (This is to say you **must** be able to `cat inpt.txt | ./cmprss | ./dcmpress | md5` and get the *same* MD5 as above.)
+ (Anything via `STDERR` is to be discarded.)
* You **must** use less than 2048 characters for your total source code.
+ *(This is **not** code-golf. You are **not** being scored based on length of source-code. This is was just a rule to keep things finite.)*
+ (Take the concatenated length of all source code if you have split it out.)
* You **must** be able to (theoretically) process similar plain-text inputs too.
+ (e.g. hard coding a mechanism which is *only* capable of outputting the provided *Shakespeare* input is unacceptable.)
+ (The compressed size of other documents is irrelevant - provided the decompressed result is identical to the alternative input.)
* You **may** use any choice of language(s).
+ (e.g. feel free to compress using `awk` and decompress using `java`)
* You **may** write two separate programs or combine them with some form of "switch" as you please.
+ (There must be clear demonstrations of how to invoke both the compression and decompression modes)
* You may **not** use any external commands (e.g. through `exec()`).
+ (If you are using a shell language - sorry. You'll have to make do with built-ins. You're welcome to post an "unacceptable" answer for the sake of sharing and enjoyment - but it won't be judged!)
* You may **not** use any built-in or library provided functions who's stated purpose is to compress data (like `gz`, etc)
+ (Altering the encoding is not considered compression in this context. Some discretion may be applied here. Feel free to argue the acceptableness of your solution in the submission.)
* Please try to have fun if choose to participate!
All good competitions have an objective definition of winning; ergo:
* Provided all rules are adhered to, the smallest **compressed** output (in `STDOUT` bytes) wins.
+ (Report your output please via `./cmprss | wc -c`)
* In the event of a draw (identical output sizes), the most community up-voted wins.
* In the event of a second draw (identical community up-votes), I'll pick a winner based on completely subjective examination of elegance and pure genius. `;-)`
## How to submit:
Please format your entry using this template:
```
<language>, <compressed_size>
-----------------------------
<description> (Detail is encouraged!)
<CODE...
...>
<run instructions>
```
I would encourage readers and submitters to converse through comments - I believe there's real opportunity for people to learn and become better programmers through codegolf.stack.
## Winning:
I'm away on vacation soon: I may (or may not) be monitoring submissions over the next few weeks and will draw the challenge to a close on the 19th September. I hope this offers a good opportunity for people to think and submit - and for a positive sharing of techniques and ideas.
If you've learned something new from participating (as a reader or submitter) please leave a comment of encouragement.
[Answer]
## Perl 5, 3651284
Just a simple word-based dictionary scheme. Analyzes the word frequency of
the corpus, and uses that to determine whether to use one or two bytes of
overhead per word. Uses two special symbols for the bytes \0 and \1 since
they do not appear in the corpus. There are plenty of other symbols that
could be used. This was not done. Does not do any huffman encoding or any
of that jazz.
Compression script shakespeare.pl:
```
use strict;
use warnings;
use bytes;
my $text = join "", <>;
my @words = split/([^a-zA-Z0-9]+)/, $text;
my %charfreq;
for( my $i = 0; $i<length($text); ++$i ) {
$charfreq{ substr($text, $i, 1) }++
}
for my $i ( 0..255 ) {
my $c = chr($i);
my $cnt = $charfreq{$c} // 0;
}
my %word_freq;
foreach my $word ( @words ) {
$word_freq{ $word }++;
}
my $cnt = 0;
my ( @dict, %rdict );
foreach my $word ( sort { $word_freq{$b} <=> $word_freq{$a} || $b cmp $a } keys %word_freq ) {
last if $word_freq{ $word } == 1;
my $repl_length = $cnt < 127 ? 2 : 3;
if( length( $word ) > $repl_length ) {
push @dict, $word;
$rdict{ $word } = $cnt;
$cnt++;
}
}
foreach my $index ( 0..$
print "$dict[$index]\0";
}
print "\1";
foreach my $word ( @words ) {
my $index = $rdict{ $word };
if ( defined $index && $index <= 127 ) {
print "\0" . chr( $index );
} elsif ( defined $index ) {
my $byte1 = $index & 127;
my $byte2 = $index >> 7;
print "\1" . chr( $byte2 ) . chr( $byte1 );
} else {
print $word;
}
}
```
Decompression script deshakespeare.pl:
```
use strict;
use warnings;
use bytes;
local $/;
my $compressed = <>;
my $text = $compressed;
$text =~ s/^.+?\x{1}//ms;
my $dictionary = $compressed;
$dictionary =~ s/\x{1}.*$//ms;
my $cnt = 0;
my @dict;
foreach my $word ( split "\0", $dictionary ) {
push @dict, $word;
}
my @words = split /(\x{0}.|\x{1}..)/ms, $text;
foreach my $word ( @words ) {
if( $word =~ /^\x{0}(.)/ms ) {
print $dict[ ord( $1 ) ];
} elsif( $word =~ /^\x{1}(.)(.)/ms ) {
my $byte1 = ord( $1 );
my $byte2 = ord( $2 );
my $index = ( $byte1 << 7 ) + $byte2;
print $dict[ $index ];
} else {
print $word;
}
}
```
Run using:
```
perl shakespeare.pl < pg100.txt >pg100.txt.compressed
perl deshakespeare.pl <pg100.txt.compressed >pg100.txt.restored
diff pg100.txt pg100.txt.restored
```
] |
[Question]
[
Your program will control a mining robot searching underground for valuable
minerals. Your robot will tell the controller where you want to move and dig,
and the controller will provide feedback on your robot status.
Initially your robot will be given an image map of the mine with some mining
shafts already present, and a data file specifying the value and hardness of the
minerals in the mine. Your robot will then move through the shafts looking for valuable
minerals to mine. Your robot can dig through the earth, but is slowed down by
hard rock.

The robot that returns with the most valuable cargo after a 24 hour shift
will be the winner. It may seem to be a complicated challenge but it is simple to make a basic mining robot (see the Sample Mining Robot answer below).
## Operation
Your program will be started by the controller with the mine image, mineral data, and equipment filenames. Robots can use the mine image and minerals data to find valuable ore and avoid hard rock. The robot may also want to buy equipment from the equipment list.
eg: `python driller.py mineimage.png minerals.txt equipmentlist.txt`
After a 2 second initialisation period, the controller communicates with the robot program through stdin and stdout. Robots must respond with an action within 0.1 seconds after receiving a status message.
Each turn, the controller sends the robot a status line:
`timeleft cargo battery cutter x y direction`
eg: `1087 4505 34.65 88.04 261 355 right`
The integer `timeleft` is the game seconds left before the end of shift. The
`cargo` is the integer value of the minerals you have mined so far less what you
have paid for equipment. The `battery` level is an integer percentage of your
remaining battery charge. The `cutter` integer level is the current sharpness of the
cutter as a percentage of the standard value. The `x` and `y` values are positive
integers with the robot position referenced from the top left corner at (0, 0).
The direction is the current direction the robot is facing (left, right, up,
down).
When your robot receives the 'endshift' or 'failed' input, your program will
soon be terminated. You might want your robot to write debugging/performance
data to a file first.
There are 4 possible commands the controller will accept. `direction
left|right|up|down` will point your robot in that direction, and require 15
game-seconds. `move <integer>` will instruct your robot to move or dig that many
units forward which takes time depending on the hardness of minerals cut and
sharpness of your cutter (see below). `buy <equipment>` will install specified
equipment and deduct the cost from your cargo value, but only if the robot is at
the surface (y value <= starting y value). Equipment installation takes 300
game-seconds. The special command `snapshot` writes the current mine image to
disk and takes no game time. You can use snapshots to debug your robot or create
animations.
Your robot will start with 100 battery and 100 cutter sharpness. Moving and
turning use a small amount of battery power. Digging uses much more and is a
function of the hardness of the minerals and current sharpness of the cutter. As
your robot digs into minerals, the cutter will lose its sharpness, depending on
the time taken and hardness of the minerals. If your robot has enough cargo
value, it may return to the surface to buy a new battery or cutter. Note that
high quality equipment has an initial effectiveness of over 100%. Batteries have the string "battery" in the name and (surprise) cutters have "cutter" in the name.
The following relationships define moving and cutting:
```
timecutting = sum(hardness of pixels cut) * 100 / cutter
cutterwear = 0.01 for each second cutting
cutters will not wear below 0.1 sharpness
timemoving = 1 + timecutting
batterydrain = 0.0178 for each second moving
changing direction takes 15 seconds and drains 0.2 from the battery
installing new equipment takes 300 seconds
```
Note that moving 1 unit without cutting any minerals takes 1 game second and uses 0.0178 of the battery. So the robot can drive 5600 units in 93 game minutes on a standard 100 charge, if it is not cutting minerals or turning.
NEW: The robot is 11 pixels wide so will cut up to 11 pixels with each pixel of movement. If there are less than 11 pixels to cut, the robot will take less time to move, and cause less wear on the cutter. If a pixel color is not specified in the mineral data file, it is free space of zero hardness and zero value.
The run is terminated when time runs out, the robot battery is exhausted, a part
of the robot exceeds the image boundary, an illegal command is sent, or robot
communication times out.
Your score is the final value of the robot cargo. The controller will output
your score and the final map image. The stderr output of your program is logged in the robot.log file. If your robot dies, the fatal error may be in the log.
## The Mine Data
### equipment.txt:
```
Equipment_Name Cost Initial_Value
std_cutter 200 100
carbide_cutter 600 160
diamond_cutter 2000 250
forcehammer_cutter 7200 460
std_battery 200 100
advanced_battery 500 180
megapower_battery 1600 320
nuclear_battery 5200 570
```
### mineraldata.txt:
```
Mineral_Name Color Value Hardness
sandstone (157,91,46) 0 3
conglomerate (180,104,102) 0 12
igneous (108,1,17) 0 42
hard_rock (219,219,219) 0 15
tough_rock (146,146,146) 0 50
super_rock (73,73,73) 0 140
gem_ore1 (0,255,0) 10 8
gem_ore2 (0,0,255) 30 14
gem_ore3 (255,0,255) 100 6
gem_ore4 (255,0,0) 500 21
```
### mine image:

The mine image may have an alpha channel, but this is not used.
## The Controller
The controller should work with Python 2.7 and requires the PIL library. I have been informed that the Python Pillow is a Windows friendly download to get the PIL image module.
Start the controller with the robot program, cfg.py, image and data files in the
current directory. The suggested command line is:
`python controller.py [<interpreter>] {<switches>} <robotprogram>`
E.g.: `python controller.py java underminer.class`
The controller will write a robot.log file and a finalmine.png file at the end
of the run.
```
#!/usr/bin/env python
# controller.py
# Control Program for the Robot Miner on PPCG.
# Tested on Python 2.7 on Ubuntu Linux. May need edits for other platforms.
# V1.0 First release.
# V1.1 Better error catching
import sys, subprocess, time
# Suggest installing Pillow here if you don't have PIL already
from PIL import Image, ImageDraw
from cfg import *
program = sys.argv[1:]
calltext = program + [MINEIMAGE, MINERALFILE, EQUIPMENTFILE]
errorlog = open(ERRORFILE, 'wb')
process = subprocess.Popen(calltext,
stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=errorlog)
image = Image.open(MINEIMAGE)
draw = ImageDraw.Draw(image)
BLACK, ORANGE, WHITE = (0,0,0), (255,160,160), (255,255,255)
W,H = image.size
dirmap = dict(right=(1,0), left=(-1,0), up=(0,-1), down=(0,1))
# read in mineral file (Name, Color, Value, Hardness):
data = [v.split() for v in open(MINERALFILE)][1:]
mineralvalue = dict((eval(color), int(value)) for
name, color, value, hard in data)
hardness = dict((eval(color), int(hard)) for
name, color, value, hard in data)
# read in the equipment list:
data = [v.split() for v in open(EQUIPMENTFILE)][1:]
equipment = dict((name, (int(cost), float(init))) for
name, cost, init in data)
# Set up simulation variables:
status = 'OK'
rx, ry, direction = START_X, START_Y, START_DIR # center of robot
cargo, battery, cutter = 0, 100.0, 100.0
clock = ENDSHIFT
size = ROBOTSIZE / 2
msgfmt = '%u %u %u %u %u %u %s'
snapnum = 1
def mkcutlist(x, y, direc, size):
dx, dy = dirmap[direc]
cx, cy = x+dx*(size+1), y+dy*(size+1)
output = [(cx, cy)]
for s in range(1, size+1):
output += [ (cx+dy*s, cy+dx*s), (cx-dy*s, cy-dx*s)]
return output
def send(msg):
process.stdin.write((msg+'\n').encode('utf-8'))
process.stdin.flush()
def read():
return process.stdout.readline().decode('utf-8')
time.sleep(INITTIME)
while clock > 0:
try:
start = time.time()
send(msgfmt % (clock, cargo, battery, cutter, rx, ry, direction))
inline = read()
if time.time() - start > TIMELIMIT:
status = 'Move timeout'
break
except:
status = 'Robot comslink failed'
break
# Process command:
movecount = 0
try:
arg = inline.split()
cmd = arg.pop(0)
if cmd == 'buy':
if ry <= START_Y and arg and arg[0] in equipment:
cost, initperc = equipment[arg[0]]
if cost <= cargo:
cargo -= cost
if 'battery' in arg[0]:
battery = initperc
elif 'cutter' in arg[0]:
cutter = initperc
clock -= 300
elif cmd == 'direction':
if arg and arg[0] in dirmap:
direction = arg[0]
clock -= 15
battery -= 0.2
elif cmd == 'move':
if arg and arg[0].isdigit():
movecount = abs(int(arg[0]))
elif cmd == 'snapshot':
image.save('snap%04u.png' % snapnum)
snapnum += 1
except:
status = 'Robot command malfunction'
break
for move in range(movecount):
# check image boundaries
dx, dy = dirmap[direction]
rx2, ry2 = rx + dx, ry + dy
print rx2, ry2
if rx2-size < 0 or rx2+size >= W or ry2-size < 0 or ry2+size >= H:
status = 'Bounds exceeded'
break
# compute time to move/cut through 1 pixel
try:
cutlist = mkcutlist(rx2, ry2, direction, size)
colors = [image.getpixel(pos)[:3] for pos in cutlist]
except IndexError:
status = 'Mining outside of bounds'
break
work = sum(hardness.get(c, 0) for c in colors)
timetaken = work * 100 / cutter
cutter = max(0.1, cutter - timetaken / 100)
clock -= 1 + int(timetaken + 0.5)
battery -= (1 + timetaken) / 56
if battery <= 0:
status = 'Battery exhausted'
break
cargo += sum(mineralvalue.get(c, 0) for c in colors)
draw.rectangle([rx-size, ry-size, rx+size+1, ry+size+1], BLACK, BLACK)
rx, ry = rx2, ry2
draw.rectangle([rx-size, ry-size, rx+size+1, ry+size+1], ORANGE, WHITE)
if clock <= 0:
break
if status != 'OK':
break
del draw
image.save('finalmine.png')
if status in ('Battery exhausted', 'OK'):
print 'Score = %s' % cargo
send('endshift')
else:
print 'Error: %s at clock %s' % (status, clock)
send('failed')
time.sleep(0.3)
process.terminate()
```
The linked config file (not to be changed):
```
# This is cfg.py
# Scenario files:
MINEIMAGE = 'testmine.png'
MINERALFILE = 'mineraldata.txt'
EQUIPMENTFILE = 'equipment.txt'
# Mining Robot parameters:
START_X = 270
START_Y = 28
START_DIR = 'down'
ROBOTSIZE = 11 # should be an odd number
ENDSHIFT = 24 * 60 * 60 # seconds in an 24 hour shift
INITTIME = 2.0
TIMELIMIT = 0.1
ERRORFILE = 'robot.log'
```
## Answer Format
The answers should have a title including programming language, robot name, and
final score (such as *Python 3*, *Tunnel Terror*, *1352*). The answer body should have
your code and the final mine map image. Other images or animations are welcome
too. The winner will be the robot with the best score.
## Other Rules
* The common loopholes are prohibited.
* If you use a random number generator, you must hardcode a seed in your
program, so that your program run is reproducable. Someone else must be able
to run your program and get the same final mine image and score.
* Your program must be programmed for *any* mine image. You must not code your
program for these data files or *this* image size, mineral layout, tunnel
layout, etc. If I suspect a robot is breaking this rule, I reserve the right
to change the mine image and/or data files.
## Edits
* Explained 0.1 second response rule.
* Expanded on robot starting command line options and files.
* Added new controller version with better error catching.
* Added robot.log note.
* Explained default mineral hardness and value.
* Explained battery vs cutter equipment.
* Made robot size 11 explicit.
* Added calculations for time, cutter wear, and battery.
[Answer]
# Python 2, Sample Miner, 350
This is an example of the minimum code for a mining robot. It just digs straight down until its battery gives out (all robots start pointing down). It only earns a score of 350. Remember to flush stdout or else the controller will hang.
```
import sys
# Robots are started with 3 arguments:
mineimage, mineralfile, equipmentfile = sys.argv[1:4]
raw_input() # ignore first status report
print 'move 1000' # dig down until battery dies
sys.stdout.flush() # remember to flush stdout
raw_input() # wait for end message
```

[Answer]
# Python 2, Robot Miner Python Template, 410
This is a mining robot template to show how a robot operates and provide a framework for building your own robots. There is a section for analyzing the mineral data, and a section for responding with actions. The placeholder algorithms do not do well. The robot finds some valuable minerals, but not enough to buy enough replacement batteries and cutters. It halts with a dead battery on its way to the surface to a second time.
A better plan is to use the existing tunnels to get close to valuable minerals and minimise the digging.
Note that this robot writes a log file of each status message it receives so you can check it's decisions after a run.
```
import sys
from PIL import Image
MINEIMAGE, MINERALFILE, EQUIPMENTFILE = sys.argv[1:4]
image = Image.open(MINEIMAGE)
W,H = image.size
robotwidth = 11
halfwidth = robotwidth / 2
# read in mineral file (Name, Color, Value, Hardness):
data = [v.split() for v in open(MINERALFILE)][1:]
mineralvalue = dict((eval(color), int(value)) for
name, color, value, hard in data)
hardness = dict((eval(color), int(hard)) for
name, color, value, hard in data)
# read in the equipment list:
data = [v.split() for v in open(EQUIPMENTFILE)][1:]
equipment = [(name, int(cost), float(init)) for
name, cost, init in data]
# Find the cheapest battery and cutter for later purchase:
minbatcost, minbatname = min([(c,n) for
n,c,v in equipment if n.endswith('battery')])
mincutcost, mincutname = min([(c,n) for
n,c,v in equipment if n.endswith('cutter')])
# process the mine image to find good places to mine:
goodspots = [0] * W
for ix in range(W):
for iy in range(H):
color = image.getpixel((ix, iy))[:3] # keep RGB, lose Alpha
value = mineralvalue.get(color, 0)
hard = hardness.get(color, 0)
#
# -------------------------------------------------------------
# make a map or list of good areas to mine here
if iy < H/4:
goodspots[ix] += value - hard/10.0
# (you will need a better idea than this)
goodshafts = [sum(goodspots[i-halfwidth : i+halfwidth+1]) for i in range(W)]
goodshafts[:halfwidth] = [-1000]*halfwidth # stop robot going outside bounds
goodshafts[-halfwidth:] = [-1000]*halfwidth
bestspot = goodshafts.index(max(goodshafts))
# -----------------------------------------------------------------
#
dirmap = dict(right=(1,0), left=(-1,0), up=(0,-1), down=(0,1))
logging = open('mylog.txt', 'wt')
logfmt = '%7s %7s %7s %7s %7s %7s %7s\n'
logging.write(logfmt % tuple('Seconds Cargo Battery Cutter x y Direc'.split()))
surface = None
plan = []
while True:
status = raw_input().split()
if status[0] in ('endshift', 'failed'):
# robot will be terminated soon
logging.close()
continue
logging.write(logfmt % tuple(status))
direction = status.pop(-1)
clock, cargo, battery, cutter, rx, ry = map(int, status)
if surface == None:
surface = ry # return to this level to buy equipment
#
# -----------------------------------------------------------------
# Decide here to choose direction, move, buy, or snapshot
if not plan and rx != bestspot:
plan.append('direction right' if bestspot > rx else 'direction left')
plan.append('move %u' % abs(bestspot - rx))
plan.append('direction down')
if plan:
action = plan.pop(0)
elif battery < 20 and cargo > minbatcost + mincutcost:
action = 'direction up'
move = 'move %u' % (ry - surface)
buybat = 'buy %s' % minbatname
buycut = 'buy %s' % mincutname
plan = [move, buybat, buycut, 'direction down', move]
else:
action = 'move 1'
# -----------------------------------------------------------------
#
print action
sys.stdout.flush()
```

] |
[Question]
[
I struggle to easily encode big numbers in ><>. If only there was a program that could find the best way for me?
## What is `><>`
[`><>`, pronounced "fish"](https://esolangs.org/wiki/Fish), is a esoteric 2dimentional programing language. We will consider a subset here, consisting of the following commands:
* `0123456789` push one number to the stack, equal to the value of the digit
* `abcdef` push one number to the stack. Interpreted as hex, so `a` will push `10`, `f` will push `15` etc.
* `*` multiply the top 2 numbers on the stack
* `+` add the top 2 numbers on the stack
* `-` subtract the top 2 numbers on the stack
* `,` divide the top 2 numbers on the stack
* `%` modulo the top 2 stack items
* `$` swap the top 2 stack values
* `@` move the top value of the stack back by 2
* `"` start string parsing mode. Push the character values of each encountered character to the stack until encountering another `"`. Only printable ASCII characters are allowed for the purpose of this challenge.
* `'` same as `"` but only ends with a `'` character.
* `~` delete the top element of the stack.
* `:` duplicate the top element of the stack
Only these commands may be used, so `/\-|#xlp.gnoi!?&><^v;[]{}()` are not allowed to be used, except inside strings. Inside strings, only ASCII printable characters may be used. Line breaks are not allowed to appear anywhere.
Your code must, when executed, push the specified number to the stack, and effect nothing else. Your snippet should be embed able in a bigger program in any place in any orientation.
You only need to handle positive integers. Your program should take at most `O(n)` time to complete encoding a single number.
## Some examples
`15` could be `f`
`32` could be `48*` or `" "`
`1111` could be `1e4f*+f*+`. This one likely can be made shorter.
You can test your programs by appending a `n;` at the end. It should print the correct number. Online interpreters include [this one](https://tio.run/#fish), [this one](https://suppen.no/fishlanguage/), and [this one](https://mousetail.github.io/Fish/). Score excludes the "printing the output" part.
## Scoring
Your score is your total length of the encoding your programs produces for the following test cases:
* all numbers between 1 and 1500 inclusive
* the first 1000 primes [(from wikipedia)](https://en.wikipedia.org/wiki/List_of_prime_numbers) whose value is greater than 1500
* All numbers of the form $$ 3^a+b $$ where `0<=a<30` and `-15<=b<=15`, whose value is greater than 1500 and not one of the first 1000 primes.
* All numbers of the form $$ 7^a + 5 \pm Fib(b)$$ for all `10 <= a < 18`, `0<=b<29`, and `Fib(x)` is the Fibonacci function, if they would not fall into any of the other categories. `Fib(0)=0`.
The [full list can be found here](https://gist.github.com/mousetail/fcd558c39f9d1a680db3de1c25e823de).
(When there is overlap only count that test case once)
Lowest score wins. First answer is tiebreaker. You don't need to golf your code.
[Answer]
# JavaScript (ES7), Score 29093
```
let cache = {};
function testSuite(list) {
let size = 0;
list.forEach(n => {
let res = solve(n).join('');
size += res.length;
console.log(n + ': ' + res);
});
console.log("Total size: " + size);
}
function solve(n, depth = 0) {
if(!cache[n]) {
cache[n] = solveNew(n, depth);
}
return cache[n];
}
function solveNew(n, depth = 0) {
if(n < 16) {
return [ n.toString(16) ];
}
if(n == 34) {
return [ `'"'` ];
}
if(n > 31 && n < 127) {
return [ '"' + String.fromCharCode(n) + '"' ];
}
if(depth > 1) {
return null;
}
let sol = [];
for(let d = Math.floor(n ** 0.5); d > 1; d--) {
if(!(n % d)) {
let r0 = solve(n / d, depth + 1),
r1 = solve(d, depth + 1);
if(r0 && r1) {
if(isAscii(r1[r1.length - 1]) && isAscii(r0[0])) {
[ r0, r1 ] = [ r1, r0 ];
}
sol.push([ ...r0, ...r1, "*" ]);
}
}
}
for(let o = -15; o <= 15; o++) {
if(o) {
let r0 = solve(n - o, depth + 1),
r1 = solve(Math.abs(o), depth + 1);
if(r0 && r1) {
if(o > 0 && isAscii(r1[r1.length - 1]) && isAscii(r0[0])) {
[ r0, r1 ] = [ r1, r0 ];
}
sol.push([ ...r0, ...r1, o < 0 ? "-" : "+" ]);
}
}
}
for(let j = 2; j <= 3; j++) {
let q = Math.floor(n ** (1 / j)),
op = ":".repeat(j - 1) + "*".repeat(j - 1);
if(q > 2) {
let r0, r1, d;
d = n - q ** j;
r0 = solve(q, depth + 1);
r1 = solve(d, depth + 1);
if(r0 && r1) {
sol.push([ ...(d ? r1 : []), ...r0, op, ...(d ? [ "+" ] : []) ]);
}
d = (q + 1) ** j - n;
r0 = solve(q + 1, depth + 1);
r1 = solve(d, depth + 1);
if(r0 && r1) {
sol.push([ ...r0, op, ...(d ? [ ...r1, "-" ] : []) ]);
}
}
}
if(!sol.length) {
return null;
}
sol = sol.map(mergeAscii);
sol.sort((a, b) => a.join('').length - b.join('').length);
return sol[0];
}
function mergeAscii(a) {
if(isAscii(a[0]) && isAscii(a[1])) {
let b0 = a[0].slice(1, -1),
b1 = a[1].slice(1, -1);
if(!b0.match(a[1][0])) {
return [ a[1][0] + b0 + b1 + a[1][0], ...a.slice(2) ];
}
if(!b1.match(a[0][0])) {
return [ a[0][0] + b0 + b1 + a[0][0], ...a.slice(2) ];
}
}
return a;
}
function isAscii(v) {
return v[0] == '"' || v[0] == "'";
}
```
[Try it online!](https://tio.run/##xVbbjts2EH3fr5gIaCytbFWymwZZr7cogj62KLB9EwyEsui1DFn0SvQm6Mbfvj1DibrYTpqiKPpgkCbP3M7McLQVT6JaldleTwqVypeXXGpaidVG0oKej/Orq/WhWOlMFaRlpe8PmZZunlXao@crIkZX2Z8MDoHFAa6CtSp/gQq3oMWdgdXAUlbAVSp/km7hBVuVFe5o5M0NwGjxFwwKclk86E19vlIFJGSQqwfo82l0QyMsgBnBo2fM9lHOH0qL3Ci8IQdY3gF27MXSODGmVO71hr2v48nW7isTfVwsvcZ1@9/6/pv82ErWPuBXSn0oixZ7wVpfbGCwoFuKfrTWGkUxFYFW97rMigeXb5fWkpFYLGj2w5nIh5Ez@nCCvKNZRK9fk7EyfXsmAxFQVBsK1qXavd@I8j1KASliunHdV1i7f0fRiaLikOc1zFaFyhFlvDTpQUG4fJji6FehN8E6Vzgq6PqawuCNN8cNdGKZTKxiTgUQ31Hq2aOmjMKuiuh7Si2nPpwaNzjjWdTiBhjjUWMBusBNGXUWzHFW/Vytsswto7iMmnKkCUWoCcDb2zAOl15flEBoGY7ZNJcL/kRj9nc5byHHdgfXgv2h2rgxBUHAYrxAwLl2aOlZkVrgaLm1VCron0Rv5tjcLshsfL/HnfoKaRNS30CaSZRIKqj6h/QpJDMcMPW/8Ahm4MZP5EwcwkvgfwOrW1ibzrGA0xnWjlK@fbxQvm6EGtx6PRLVHjDnxglKuZdCu1uOmHsJeR2eNVSCsUcwNj3N2NiEnbaEc/dw8h7Z7tZG0svs4zBP/64NhrS6KYiEqhu0tDe2RKv9uL2Ma4ZrxIDpnvsIlG2bABBJcSkIRvx3gZy7bbtuctn7QZ3wo8T66lL@2htYv3@M3Ym9u5PlgzTVbjTzcaVK7bpiTInHY1K087Drk@T0rI61MQcl6JvhpOnsuKIdMLbPBLdZv/FEHHV9xzWXcBoYFlR5tpIuaJn034ckMvfR8L4r41dJiHA1Rj@Dhl3dTpzmCrmDOZ91@vbMpEU0yqee7fdjpz9q9Ydf1h9e0B/@jf7eEBdDTi1bT7WtBvTEJjCGeUB@/tz@dUYOpF96wr@X2c4M0@fe8J6elI4uD3Iwtm9pymrrCTj1TuBrkVdyMG534tOXZuvpAJ7xtMX7BhHe@T1vLs7cU5tnfNXOwxW2wB@A/E7Jj3QvtcvmrXFEzjO@YONv30XvsLXvax0zz7Ew5Lg72try5A9LkaY4qgM/doqF@fzEckszXq1We5/YWZnYWZkMH3b2bMaECS6Yrp7584ld6r3MQzcsF3Cm@zyOUWSMW571OPe0581f/gI "JavaScript (Node.js) – Try It Online")
[Answer]
# Python 3, score 28806
```
import functools
import itertools
#import sympy
import math
STRINGABLE = sorted(b'0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&()*+,-./:;<=>?@[\\]^_`{|}~ ', reverse=True)
MAX = max(STRINGABLE)
ONECHAR = [*STRINGABLE, *range(15, 0, -1)]
MULTIPLES_O = {a*b:(a,b) for a in ONECHAR for b in ONECHAR}
SUMS_O = {a+b:(a,b) for a in ONECHAR for b in ONECHAR}
MM = {*range(16), *STRINGABLE}
def stringify(n):
infix = ''
prefix = ''
postfix = ''
options = []
while True:
if n < 16:
postfix = hex(n)[2:] + postfix
break
if n in STRINGABLE:
prefix += chr(n)
break
if n in SUMS_O:
a,b = SUMS_O[n]
postfix = '+' + postfix
if a < 16:
postfix = hex(a)[2:] + postfix
else:
prefix += chr(a)
if b < 16:
postfix = hex(b)[2:] + postfix
else:
prefix += chr(b)
break
if n in MULTIPLES_O:
a,b = MULTIPLES_O[n]
postfix = '*' + postfix
if a < 16:
postfix = hex(a)[2:] + postfix
else:
prefix += chr(a)
if b < 16:
postfix = hex(b)[2:] + postfix
else:
prefix += chr(b)
break
for i in ONECHAR:
if n+i in SUMS_O or n+i in MULTIPLES_O or n+i in ONECHAR:
n += i
postfix = '-' + postfix
if i < 16:
postfix = hex(i)[2:] + postfix
else:
prefix += chr(i)
break
if n-i in SUMS_O or n-i in MULTIPLES_O or n-i in ONECHAR:
n -= i
postfix = '+' + postfix
if i < 16:
postfix = hex(i)[2:] + postfix
else:
prefix += chr(i)
break
else:
for i in ONECHAR:
c = set(range(n%i, MAX+1, i)) & MM
if c:
if 0 in c:
prefix += chr(i)
postfix = '*' + postfix
n //= i
break
j = max(c)
if j in STRINGABLE:
prefix += chr(j)
postfix = '+' + postfix
else:
postfix = hex(j)[2:] + '+' + postfix
if i in STRINGABLE:
prefix += chr(i)
postfix = '*' + postfix
else:
postfix = hex(i)[2:] + '*' + postfix
n = (n-j) // i
break
# make n smaller ...
options.append("'" + prefix + "'" + most(n,0) + postfix)
options.append("'" + prefix + "'" + postfix)
return min(options, key=len)
def evaluate(s):
import io
s = io.StringIO(s)
stack = []
while True:
c=s.read(1)
if c=='': break
if c in '0123456789abcdef':
stack.append(int(c, 16))
elif c in '*+-%':
stack.append(eval(f'{stack.pop()}{c}{stack.pop()}'))
elif c == ':':
stack.append(stack[-1])
elif c == '~':
stack.pop()
elif c == '$':
stack.append(stack.pop(-2))
elif c == '@':
stack.insert(-2, stack.pop())
elif c == '"':
while True:
c = s.read(1)
if c == '"': break
stack.append(ord(c))
elif c == "'":
while True:
c = s.read(1)
if c == "'": break
stack.append(ord(c))
elif c == ',':
raise NotImplementedError
return stack
def factor(n):
from collections import Counter
p = 2
l = []
while n > 1:
if p*p > n:
l.append(n)
break
if n%p:
p += 1 + p%2
else:
l.append(p)
n //= p
return Counter(l)
#factor = sympy.factorint
def two_squares(n):
C = factor(n)
for i in C:
if i%4 == 3 and C[i]%2: return False
return True
def product(l):
z = 1
for i in l:
z *= i
return z
def divisors(n):
F, C = zip(*factor(n).items())
for t in itertools.product(*(range(i+1) for i in C)):
yield product(i**j for i,j in zip(F, t))
#from sympy import divisors
@functools.lru_cache(None)
def power(n):
if n < 2: return ''
options = [':'+power(n-1)+'*']
for i in divisors(n):
if 1 < i*i <= n:
options.append(power(i)+power(n//i))
return min(options, key=len)
def nth_root(k, p):
x = int(k**(1./p))+1
x1 = x-1
while x1 < x:
x = x1
xp1 = x**(p-1)
x1 = ((p-1)*x+k//xp1)//p
return x
#nth_root = lambda k,p:sympy.integer_nthroot(k, p)[0]
def massage(x, p):
options = [most(x) + power(p)]
if p%2 and p > 2:
options.append(most(x*x) + power(p//2) + most(x) + '*')
return min(options, key=len)
def powerful(n):
possibilities = []
for p in range(2, n):
x = nth_root(n, p)
if x == 1:
d2 = (x+1)**p-n
if d2 < n and x+1 < n: possibilities.append((d2,x+1,p,'-'))
break
d1 = n-x**p
if d1 == 0:
if x < n: possibilities.append((d1,x,p,None))
continue
d2 = (x+1)**p-n
if d1 < n and x < n: possibilities.append((d1,x,p,'+'))
if d2 < n and x+1 < n: possibilities.append((d2,x+1,p,'-'))
options = [most(d,0) + massage(x, p) + s if d else massage(x, p) for d,x,p,s in sorted(possibilities)[:2]]
return min(options, key=len)
def power2(n):
possibilities = []
for b in range(2, 20):
bc = 1
for c in range(1, n):
bc *= b
a = n//bc
if a*bc == n:
possibilities.append((a,b,c,None,''))
continue
d = (a+b)*bc - n
possibilities.append((a+1,b,c,d,'-'))
if a == 0: break
d = n - a*bc
possibilities.append((a,b,c,d,'+'))
a,b,c,d,s = min(possibilities, key=lambda t:t[0]+t[1]+(t[3]or 0))
postfix = most(a) + '*' if a > 1 else ''
if d is None: return most(b) + power(c) + postfix
return most(d) + most(b) + power(c) + postfix + s
def split(n):
D = sorted(i for i in divisors(n) if 1 < i*i <= n)
if len(D) == 0: return
options = []
for d in D[-3:]:
options.append(most(d,0) + most(n//d,0) + '*')
options.append(most(d,0) + ':' + most(n//d - d) + '+*')
options.append(most(n//d,0) + ':' + most(n//d - d) + '$-*')
return min(options, key=len)
def optimize(s):
return s.replace("''", '')
winners = [0,0,0]
@functools.lru_cache(None)
def most(n, depth=1):
if n < 16:
return hex(n)[2:]
if n < 31:
return hex(n-15)[2:] + 'f+'
if depth:
return stringify(n)
options = [stringify(n), powerful(n), split(n)]#, power2(n)]
options = [(optimize(s),i) if s else (s,i) for i,s in enumerate(options)]#list(map(optimize, filter(None, options)))
s,i = min(options, key=lambda t:len(t[0]) if t[0] else 1000000000)
winners[i] += 1
return s
#most(7**2)
def fib(n):
a,b = 0,1
for _ in range(n):
a,b = b,a+b
return a
if __name__ == '__main__':
L = sorted(I for I in {*range(1, 1501), *[i for i in range(1501, 7920) if list(factor(i).values()) == [1]], *[3**a+b for a in range(30) for b in range(-15, 16)], *[7**a + 5 + m*fb for fb in [fib(b) for b in range(30)] for a in range(10, 18) for m in [1,-1]]} if I > 0)
O = [most(i,0) for i in L]
for i,j in zip(O, L):
if evaluate(i)[0] != j:
print(i, j, evaluate(i))
break
print(f'{j}: {i}')
else:
print('Success!')
s = ''.join(O)
print(len(s))
print('\n' in s)
print(winners)
```
[Try it online!](https://tio.run/##7Vlbd9vGEX7nr1hLVoAFAZKgIjthzdSOLCdqJCu17DYtzbIAuLSWAhYIAFqUFOWvu7MXXAleXOel55R6ERY7929mZxbRbXoVskMruo1uP32iQRTGKZotmJeGoZ@01AJNSSwX9tVKchtEt9nrwEmvWq3Lt29OX//w4vuzEzRECayTqe5qPbt/@PXRk6fffOu43pTMPlzR@bUfsDD6NU7Sxceb5e3di@@PX568@uHH07/8dHb@@uLnv765fPvub3//5R//fLS3//jgKx0bbdPqdAd/ejb87s/PR@/fj/81@ff9bw@/I81EMflI4oQM38YLglvnL34B8YGz1At9cOvi9cnxjy/ewJuRUaybyIgd9oHo9pGJeiaybDxunb87e3v689nJ5eQCtt87hjvQHdPFaBbGyEGUoYwZX3BLCw@ty3fnGVn7M8jOzzlJpssTDHoVSj60WuA2lKQxZR/o7FZneNBC8KNsRpdAqGniMYpJ9TlM0spCGKU0ZAn3wVgs3FxRnyDuNslQMJ0hhp4h@0mxVGV2RZagwag/GKN2tlzZ6sbEua7yA1sLe2qMpdbtIfKuYmC8Cyvh5Cob8DToJt@M2HiN7lpbW6M08HYazF413dlkOvET0sCgYqKD64LdnQS7XyrY3cW3JfA3Obj0eoOXjf97udnLPPNpKfMHdSVZmxYIR7BbLZRrUrHayIX/GNeGbjBVs9aFSClC13hr1WN0k8fWe23VcxSvbKp6L/ORVfeR1egja5uPrC0@av8P@miV0WbM8Z/Hj2uS6vL4YQfURHCItm0TUYzRV@j8vMl6r1lfeNPj0ta83smkzykp1ZB2u00xXQ@n7DdXLYOH1xk133SIrbduvpN17W3WrcfHKtjmGdi2sxUg/q/s@oOi9jl25Um0nS0DEp1ZcwyAWIOHKhb2IfrXBOiSwPF9EqNOp5O/VH1Tx4kiwqb6nrbHxSt3IPkYgDY6M3u40Ay3diWuEMQkXcQMBZTpitZE1@R26BNojkQnSD46/sJJiZ5kjaBq0kPxxBs8GnYuRb94egG75HLqeNebez9vmHTALVPdxuXGwBsONW2w2jB4HDor/b1WjacQm1lPWap7JhRNjEsVK2dltK2DTeTccH2m3cvFKIx0/HDvPVSetVXWQ0DiYBNf8TCy7HEj6e@NpEJa0/bHWyUJWqvfrOjzRnLKEhjAgMgsi29ksFdj0BToSuVfCXklxIrlmtpZMS6Mp1BAm5QCmP/RSnGWX6aUZtY8FTs0Ieh1mJ4GkU8CwmCAPYnjMC7npWAu83DmwJAc5@PYLA4D5IVQPjw5Z6m0PA4XwEkyicC2vvjPr6ciQ98huzKHRUYEa6yqpJ8ZtnVUOohqkxav3TYvNwf9Df1CLiCqCpCHa1T2hbJM96Ew7Utv8Njxm4GOfISEl75Kb8JJ8uvCiUmSO@wYNuc@bFV6leOKI@jB1zxgh8hhU3Q8ouOD/iDT4ZUDFpSV4qCSMqM4nC68FNST3O5Anl2V4xdy7pCR9Q6K051kM6UfaRLGhd6vTKH6HY10I9e/Q1MSJFlOcgEpF5BfnHQybQzVZ9G2jUsGY1yockuJP83Vp4YxlxtN0YRwuaBCioXXOeiExzO4Zeq2Ws/za5yOHy8mnuNdEf11yAiW7glvSIFeNfcXjl29NIAi2lZElo3bcAyPq95c8ZRibANjakC7PKyjuXY6Su4UZ2K6XYp3PRVZejWJwzDVr00UKfm8deBnzrVh6HanG2HclgBY2vBmadml/FtyLZeFepx2aRePkSABRpFVKkuCkS7WjGX7utuFfbjbraTJEuKUaQe7fSdwpw66NqOBTBXQkHwg8QT2FAaMemNpV@AkiQN4WRZmlWIi@o6l7Dq4yyI8zsIJaS4ShheR/mBdNyMZGGUW3W4fZy2NWIdI7xoFwWK28HMIQG@TUJf6NKWkdPXEMRNxzMhkgHOtjBnu@zyejBtehtOSFwO7CqRpn8dhCTllGJHF6jMjvH4G@ObugD38/0FVs8wd@rRvwg4zMmFExptK7JRHnlmAiKisHF8eot7KZL/cKNQ2lyBS5GZVpheylLIFaW0zVIrOjdxBGowHuOLXL3JSHZNT2QtX0AvPiRAkjp3aO46IqVAs4bhQ98cV@Xg06I/Hn4PE/i44dCs47PdKQHS9/MzIdnvFbruKWkUAx4hbvTrjQOl2XW/lLsxwRSfCGm@lGvzumK7pCZiYWh2djWgRiOGAcdou5tIsxFo7yIHgcknThiwQd3gC4g3tF5fFQAi3rLWrPdMSFLMVHiIe3AqdCrGsn@kghRrZTkf2uK2no8MxxKanuBSDo8Cio4qY1B3aLIk/dcIJQNIEcbfmp5@gc4ui6OHayFneN83L5RoKDnx1ix@BKTkoXxYfSmjjMVo/PXGmMeBcf4lVHKQuzXf8Iq0415cj63Aw3nwOZEkrhtluVz3m5X8LGfQHZWKAgXCM1t5GXxK1hsVja/cjiC8H9K4Yj7POHWaKyHc8AkO4tmdC@IHghjJGYuGvngl/461tk5r00ZRE6dXQrrZP5etAJbb4XlLeeGg3b7Tso/yaY9YuAMqFrVCUPwnVo19@Z5aPZTPH4HjfLKrkuM5AL/nRpAKJicwbPeHPsiMVtZqwRUBifiOh6IG1T8FNgRPlbEw0oz6fFkT5yiRhlbHAUmV8NapZrnO883wXevB/pCp2L/tJNiqcMCKIYacSfujCROyeGkZfQWVG3TwX5QeOnllMCJOi0pfLvNzomlBSy/ydVgtUm0yYE5DJRAyYk0ngUDaZqDnzrMj2UyHglAvIP/uZyD7q2fzb36hUDLLvkz14//RbOJxE9nPnqtGD4g6/DyJ89uBSoR6OOY9DwwANi6@PktFhD9fPPIt//LSfYEEFznEAe0c8C42ZJJ@JzSPuLHeFGhiO60LsHjD8Rm4NBK1tWqDWA9f9FAqwitZF3i1Qs1cahs5Kc0Ux81yY6Kw6V@QXYZS3y@jREM3rHxd5909NNDfLmze1dZJkpt3PHwbonj6oslOdk@Um7XLheSRJHqk9ifjU2pmHgOILdRCJjRy8CS6vaO@ZJrqc8qICL259@vQf "Python 3 (PyPy) – Try It Online")
There are three methods this uses.
The first is to try to express the number using a single string of characters, and several multiplications/additions (more or less, it can also use single digits (0-f) outside of the string).
The next is to try to find a power that is close to the number, and express the number as `a^p + b`.
The third is to express the number as a product of two numbers (of similar magnitude).
It also removes any occurrences of `''` (this saves nearly 200 bytes!)
[Answer]
# Python, score=28800
```
import requests
import string
import itertools
real_printables = {ord(i) for i in (
set(string.printable) - set('\n\t\r\x0b\x0c'))}
def get_factors(num, quote):
quote_free_printables = real_printables - {ord(quote)}
terms = []
factors = []
while num > 0:
if num <= 15:
terms.append(num)
break
if num in quote_free_printables:
terms.append(num)
break
for factor in sorted(quote_free_printables,
reverse=True):
if num % factor == 0:
break
else:
for factor in sorted(quote_free_printables, reverse=True):
if num % factor in quote_free_printables:
break
else:
for factor in range(15, 4, -1):
if num % factor == 0:
break
else:
factor = 15
assert factor != 1
terms.append(num % factor)
factors.append(factor)
num //= factor
return terms, factors
def encode_char_safe(char, quote):
if char in real_printables - {ord(quote)}:
return chr(char)
elif 0 <= char <= 15:
return f"{quote}{'0123456789abcdef'[char]}{quote}"
else:
raise ValueError(f"invalid char: {char}")
def encode_naive(num, quote):
string = ''
multiplication_section = ''
terms, multiples = get_factors(num, quote)
# print(terms, multiples)
for index, (term, multiple) in enumerate(zip(terms, multiples)):
if term != 0:
string += encode_char_safe(term, quote) + encode_char_safe(multiple, quote)
if index == 0:
multiplication_section = '+' + multiplication_section
else:
multiplication_section = '+*' + multiplication_section
else:
string += encode_char_safe(multiple, quote)
if index != 0:
multiplication_section = '*' + multiplication_section
assert len(terms) == len(multiples) + 1
assert 1 not in multiples
if terms[-1] != 1 or len(terms)==1:
string += encode_char_safe(terms[-1], quote)
if len(multiples) > 0:
multiplication_section = '*' + multiplication_section
return f"{quote}{string}{quote}{multiplication_section}".replace(
quote*2, "")
def encode_maybe_power(num, quote):
return min(
(
encode_naive(int(num ** (1/a)), quote)+b for a, b in zip(
(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18),
('', ':*', '::**', ':*:*', '::::****', ':*::**',
'::::::******', ':*:*:*', '::**::**', ':*::::****',
'::::::::::**********', ':*:*::**',
'::::::::::::************', ':*::::::******',
'::**::::****', ':*:*:*:*',
':::::::::::::::****************',
':*::**::**'
))
if int(num ** (1/a))**a == num
),
key=len
)
def encode_maybe_divide(num, quote):
return min(
(
(
encode_maybe_power(num, quote) if i == 1
else
(
quote + encode_char_safe(i, quote) + quote +
encode_maybe_power(num//i, quote) + '*'
).replace(quote*2, '')
)
for i in itertools.chain(
range(1, 16),
real_printables - {ord(quote)}
)
if num % i == 0
),
key=len
)
def number_with_subtraction(num, sub, quote):
if sub == 0:
return encode_maybe_divide(num, quote).replace(quote*2, '')
elif sub > 0:
return (
quote + encode_char_safe(abs(sub), quote) + quote +
encode_maybe_divide(num-sub, quote)
).replace(quote*2, '')+'+'
elif sub > -16:
return (
encode_maybe_divide(num-sub, quote) + quote +
encode_char_safe(abs(sub), quote) + quote
).replace(quote*2, '')+f'-'
else:
return (
quote + encode_char_safe(abs(sub), quote) + quote +
encode_maybe_divide(num-sub, quote)
).replace(quote*2, '')+f'$-'
def encode(num):
if num < 16:
return '0123456789abcdef'[num]
return min((
number_with_subtraction(num, b, quote).replace(quote*2, '')
for quote in ('"', "'")
for b in itertools.chain(range(-15, 16), *(
(i, -i) for i in real_printables - {ord(quote)}
))
if num-b > 0
), key=len)
# test_cases = range(500, 510)
test_cases = requests.get(
"https://gist.githubusercontent.com/mousetail/"
"fcd558c39f9d1a680db3de1c25e823de/raw/"
"c91113d663cf4d3f3cef7ad44d5ced22239f964e/test_cases.csv").text.split("\n")
total_length = 0
for test_case in test_cases:
res = encode(int(test_case))
total_length += len(res)
print(f"{test_case:>8}\t{res:>8}")
print(total_length)
```
Technically runs in `O(log N)`.
Basically runs in 3 steps:
* Try adding or subtracting every printable character to try to make it a perfect multiple
* The dividing by every printable to make it a perfect power
* If it is a perfect power try rooting it. This is the most important saving, and the main goal of the top 2 steps.
* Now the main part of the loop. Basically we want to convert the remaining number to base `ord('~')`. However, if this would lead to digits that are not printable we take a smaller base instead. Base is adjusted for each individual digit.
The score for just the last step would be `33749`.
] |
[Question]
[
This is a challenge to write bots to play the 1st and 2nd players in the following simple poker game.
## Rules of the poker game
There are two players, A and B. Each antes $10 into the pot, and is dealt a card, which is a real number in the range [0, 1).
Player A goes first, and may pass or bet. If A passes, then there is a showdown; the cards are revealed, and whichever player had the higher card wins the pot.
If A bets, A chooses an amount \$b\$ to bet. \$b\$ must be an integer multiple of $1, in the range [$1, $50], and no greater than the amount of money A has at the time.
**EDIT (19 Aug 2020)**: Moreover, \$b\$ must be no greater than the amount of money B has at the time, to enable B to go all-in to call, if B wants to.
A adds \$b\$ to the pot.
Then B may fold or call.
If B folds, A wins the pot with no showdown.
If B calls, B adds \$b\$ to the pot, and there is a showdown.
**EDIT (19 Aug 2020)** Note that B will always have enough money to call, as A is not allowed to bet so much that B would not have enough.
## Rules of the tournament, matches and sessions
The bots which are the entries to this contest will compete in an all-play-all tournament consisting of matches. Every pair of entries go head to head in a match.
Each match has two contestants (call them X and Y). Each match consists of \$n\$ sessions, where \$n\$ is a number I will choose, depending on how many entries there are and how much time I feel like devoting to running the engine.
At the start of each session, the tournament controller gives each contestant $100. There then follow a series of games. The games in each match alternate games where X's A-bot plays Y's B-bot, and games where Y's A-bot plays X's B-bot. Each session will continue until either 50 games in the session have been played, or one contestant no longer has enough money to start a further game (specifically, to put a $10 ante into the pot).
Where a session contained \$g\$ games, and the winner gained an amount \$m\$ of money, that winner is awarded \$m/\sqrt{g}\$ points, and the loser loses the same amount of points. (The amount of points is higher, the lower \$g\$ is, so as to reward bots that consistently beat their opponents and thus win their opponent's entire stack quickly. However, I don't want very quick sessions to dominate the scoring too much, so I divide only by \$\sqrt{g}\$ and not by \$g\$.)
The winning bot is the one who won most points over the course of all the matches it played in the tournament (as described in the previous paragraph).
## Interfaces of procedures in an entry
An entry should contain C procedures which have the following prototypes:
```
int a(const Bot *bot);
int b(const Bot *bot, const int aBet);
```
where types are defined as follows:
```
typedef float Card;
typedef long Money;
typedef Money (*AProcType)(const void* bot);
typedef int (*BProcType)(const void* bot, const Money aBet);
typedef struct Bot
{
AProcType a;
BProcType b;
Card card, opponentsPreviousCard;
Money money, opponentsMoney;
float f[50]; // scratch area for bots to use as they will
} Bot;
```
Where `bot` points to an entrant's bot, just before `bot->a` or `bot->b` is called, the card dealt to that bot and the amount of money it has are assigned to `bot->card` and `bot->money`.
If a game ended in a showdown, then, afterwards, each bot's card is assigned to the other bot's `bot->opponentsPreviousCard`. By contrast, if the game ended with one player folding, then the controller does not reveal the cards: instead, a negative value is assigned to `bot->opponentsPreviousCard`.
In my sandbox proposal for this KotH, I asked whether or not the controller should *unconditionally* reveal both cards to both bots. It got a comment that in online poker "the winner has the choice whether they show or hide their cards". Seeing as a bot can't possibly do worse by hiding its card than by revealing it, I have opted instead to never reveal the cards dealt in a game where one player folded.
The array `f` is provided to enable a bot to maintain state between games.
In a game where the bot `bot` is the A-player, the controller will call the function `bot->a(bot)`.
`0. <= bot->card < 1.0`. `a` must return the amount (in $) the bot is to bet. If `a` returns 0 or a negative value, that means the bot will pass. Otherwise, the bot will bet the value returned by `a`, $50, or all the player's money, whichever is the smallest.
In a game where the bot `bot` is the B-player, the controller will call the function `bot->b(bot, aBet)` where the A-player has just bet an amount $`aBet`.
`0. <= bot->card < 1.0`. The controller calls `bot->b` only if both the following conditions are true:
* `aBet > 0` because if A had passed, B does not get to act.
* `bot->money >= aBet` because, if A had bet but B could not afford to call, B must fold.
`bot->b` must return 0 if the bot is to fold, and any other value if the bot is to call.
X and Y will never be the same entry. So, even if you think each of your bots would be able to tell if its match-opponent is your other bot... it won't be.
My sandbox proposal for this KotH expressed the game in terms of dealing cards from a pack. In such a game, if cards were not returned to the pack, the value of each card would change depending on how many cards above it and below it had not yet been seen, which would depend on the play. The proposal got a comment that cards are returned to the pack after each round. But in that case the above effect does not occur. So the cards might as well be independent variates from the uniform distribution on the interval [0, 1).
Each entry's tournament score will be the sum of its match-scores. [Note that each entry is pitted against every other entry, so all entries play equal numbers of matches.]
Loopholes are forbidden, as is trying to cheat. No bot may try to read or write or tamper with anything external to it, including the controller or other bots. However, calls to `rand` (in reasonable quantities) are allowed.
**EDIT** Tue 11 Aug 20 to clarify that using `rand` is allowed, and to give direct read-access to the amount of the opponent's money.
The following is a controller, provided just so that entrants can test their bots. My actual controller might contain additional code as required.
```
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
// Return codes from playVonNeumannPokerGame
#define G_FOLD 0
#define G_SHOWDOWN 1
#define G_MAYNOTBOTHPLAY 2
#define ANTE 10
#define BET_LIMIT 50
#define INIT_STACK 100
typedef float Point, Card;
typedef long Index, Money, Stat;
typedef Money (*AProcType)(const void* bot);
typedef int (*BProcType)(const void* bot, const Money aBet);
typedef struct Bot
{
AProcType a;
BProcType b;
Card card, opponentsPreviousCard;
Money money;
float f[50]; // scratch area for bots to use as they will
} Bot;
#define GAME_NAME_MAX 31
typedef struct Entrant
{
Bot *bot;
char name[GAME_NAME_MAX+1];
Point vp;
Money mny;
} Entrant, *PEntrant;
long nEntrants;
Entrant *plr;
#define NSESSIONSPERMATCH 500
#define MAXNGAMESPERSESSION 50
unsigned long nGamesInTotal, prngSeed;
static void playVonNeumannPokerTournament();
static void playVonNeumannPokerMatch(PEntrant c1, PEntrant c2);
static long playVonNeumannPokerGame(PEntrant a, PEntrant b);
static void initBots();
static void tournament2Init(long nPlayers);
static void tournament2MatchPlayers(long *pi1, long *pi2);
static float fRand();
static int cmpByVP(const Entrant* e1, const Entrant* e2);
// <nEntrants> <seed>
int main(int argc, char** argv)
{
sscanf_s(argv[1], "%ul", &nEntrants); // for public engine
sscanf_s(argv[2], "%ul", &prngSeed);
srand(prngSeed);
playVonNeumannPokerTournament();
} // main
static void playVonNeumannPokerTournament()
{
long pi, pj;
PEntrant e;
nGamesInTotal = 0;
//nEntrants = sizeof(aProc)/sizeof(aProc[0]); // works only if engine includes bot data
plr = (PEntrant)calloc(nEntrants, sizeof(Entrant));
for(pi=0; pi<nEntrants; ++pi) // Initialise the entrants
{
e = &plr[pi];
e->vp = 0;
}
initBots(); // Connect each entrant to its bot
for(pj=1; pj<nEntrants; ++pj) // all-play-all tournament
for(pi=0; pi<pj; ++pi)
playVonNeumannPokerMatch(&plr[pi], &plr[pj]);
} // playVonNeumannPokerTournament
static void playVonNeumannPokerMatch(PEntrant c1, PEntrant c2)
{
long si, mgi=0, sgi, r;
Point win1, win2;
c1->bot->opponentsPreviousCard = -1.0;
c2->bot->opponentsPreviousCard = -1.0;
for(si=0; si<NSESSIONSPERMATCH; ++si)
{
c1->mny = INIT_STACK;
c2->mny = INIT_STACK;
for(sgi=0; sgi<MAXNGAMESPERSESSION; ++sgi)
{
if(mgi&1) // c1 & c2 swap roles in the match's every game
r = playVonNeumannPokerGame(c2, c1); // c2 is A; c1 is B
else // even-numbered game
r = playVonNeumannPokerGame(c1, c2); // c1 is A; c2 is B
++mgi;
if(r==G_MAYNOTBOTHPLAY)
break; // one player can't afford to continue the session
if(r==G_SHOWDOWN)
{
c1->bot->opponentsPreviousCard = c2->bot->card;
c2->bot->opponentsPreviousCard = c1->bot->card;
}
else
{
c1->bot->opponentsPreviousCard = -1.0;
c2->bot->opponentsPreviousCard = -1.0;
}
}
win1 = (c1->mny - INIT_STACK +0.0)/sqrt(sgi); // sgi must > 0. Take sqrt so as not to over-reward quick wins
win2 = (c2->mny - INIT_STACK +0.0)/sqrt(sgi);
c1->vp += win1;
c2->vp += win2;
} // for each session in the match
} // playVonNeumannPokerMatch
static long playVonNeumannPokerGame(PEntrant a, PEntrant b)
{
_Bool bCalls;
Card ax, bx;
Money aBet;
long r=G_SHOWDOWN;
// Unless each of the game's players can afford their ante, they cannot play a game.
if(a->mny < ANTE || b->mny < ANTE)
return G_MAYNOTBOTHPLAY; // players may not both play
a->bot->card = ax = fRand();
b->bot->card = bx = fRand();
a->bot->money = b->bot->opponentsMoney = a->mny;
b->bot->money = a->bot->opponentsMoney = b->mny;
// Call A's bot to find out how much money A wants to bet.
aBet = a->bot->a(a->bot);
// But A may not bet more money than A has, nor yet more than the bet-limit
aBet = aBet < 0 ? 0 : a->mny < aBet ? a->mny : aBet;
aBet = aBet > BET_LIMIT ? BET_LIMIT : aBet;
// EDIT 19 Aug 2020: A may not bet more money than B has.
aBet = aBet > b->mny ? b->mny : aBet;
// [If B cannot afford to call, B must fold; there is no need to call B's bot in such a case. Otherwise,] call B's bot to find B's reply (fold or call)
// Treat A passing as A betting 0 and B calling
bCalls = aBet < 1 ? 1 : b->mny < aBet ? 0 : b->bot->b(b->bot, aBet);
if(!bCalls) // B folds
{
a->mny += ANTE;
b->mny -= ANTE;
r = G_FOLD;
}
else if(ax>bx) // B calls A's bet; A wins the showdown
{
a->mny += ANTE+aBet;
b->mny -= ANTE+aBet;
}
else // B calls A's bet; B wins the showdown
{
a->mny -= ANTE+aBet;
b->mny += ANTE+aBet;
}
return r;
} // playVonNeumannPokerGame
/*#############################################################################
Bots
This section is subject to change, and has my copies of user-submitted code for bots' a- and b-procedures
###############################################################################
*/
// This bot is so naive, it never bluffs.
static Money naiveA(const Bot *bot)
{
Card x=bot->card;
return 50.*x-25.;
}
static int naiveB(const Bot *bot, const Money aBet)
{
return bot->card>.5;
}
// This bot treats it like 3-card Kuhn poker
static Money kuhn3A(const Bot *bot)
{
Card x=bot->card;
Money m=bot->money;
Money bet = 10;
if(m<bet)
bet = m;
return 9.*x<1. || 3.*x>2. ? bet : 0;
}
static int kuhn3B(const Bot *bot, const Money aBet)
{
return bot->money>=aBet && 9.*bot->card>5.;
}
typedef char *String;
static String botName[] = {"naive", "Kuhn3"};
static AProcType aProc[] = {naiveA, kuhn3A};
static BProcType bProc[] = {naiveB, kuhn3B};
static void initBots()
{
Bot *pBot;
long i, j;
for(i=0; i<nEntrants; ++i)
{
pBot = (Bot*)calloc(1, sizeof(Bot));
pBot->a = aProc[i];
pBot->b = bProc[i];
for(j=0; j<50; ++j)
pBot->f[j] = 0.0;
plr[i].bot = pBot;
strncpy_s(plr[i].name, GAME_NAME_MAX+1, botName[i], GAME_NAME_MAX);
}
} // initBots
static float fRand()
{
float r = rand();
return r / RAND_MAX;
}
static int cmpByVP(const Entrant* e1, const Entrant* e2)
{
return e2->vp > e1->vp ? 1 : -1; // map from floats to int +-1
}
```
[Answer]
# LikeMe Bot
Here's a simple bot. It mostly just assumes that the other bot bets roughly like it does.
```
int likemea(const Bot *bot){
// Always go big if we can't play again if we lose.
if (bot->money < 10) return bot->money;
// Force an all-in if there's a decent change we win.
if (bot->card > 0.5 && bot->opponentsMoney <= 50) return bot->opponentsMoney;
float max_pass = 0.5;
float min_max_bet = 0.9;
// Increase risk tolerance when in the lead.
float lead = bot->money / (bot->opponentsMoney + 20);
if (lead > 1){
// Don't go crazy.
lead = lead / 2 + 1;
if (lead > 1.5) lead = 1.5;
max_pass /= lead;
min_max_bet /= lead;
}
if (bot->card < max_pass) return 0;
if (bot->card > min_max_bet) return 50;
return (int)((bot->card - max_pass) / (min_max_bet - max_pass) * 50);
}
int likemeb(const Bot *bot, const int aBet){
// Get what I would have bet if I was a.
int my_bet = likemea(bot);
if (bot->money < 50){
// If I'm being pushed all-in, assume the other bot is playing riskier.
my_bet = (int)(my_bet * 1.2);
}
if (my_bet >= aBet) return aBet;
return 0;
}
```
Please have mercy on my C. It's been a while, and I've never done much C anyway.
[Answer]
# Con-stats Bot
Uses the power of probabilities and brute-force to choose better numbers than just '50%' or '50 money', the right constant stats to con you.
```
static Money constatsA(const Bot* bot)
{
Card x = bot->card;
Money money = bot->money - ANTE; // ANTE is not taken out before call
Money oppMoney = bot->opponentsMoney - ANTE; // same as above
// Going all in is a bad strat normally?
// Just put a minimum card, that'll fix it
if (x > 0.72 && money < ANTE) return money;
// If my card is over 0.71, I have an optimial chance of winning
// make sure not to bet all _my_ money
// BET_LIMIT + ANTE means that I can bet even harder, as they
// don't need to go to 0, just low enough they can't ANTE anymore.
if (x > 0.71 && oppMoney <= BET_LIMIT + ANTE && oppMoney < money)
return oppMoney;
// yep, 1.
// Turns out, most bots self-destruct under their own weight?
// Or they just get confused by the quite low bet.
return 1;
}
static int constatsB(const Bot* bot, const Money aBet)
{
Card x = bot->card;
Money money = bot->money - ANTE;
if (x > 0.90) return true;
// if it has enough for two more rounds
// and a 55% of winning, go for it
return x > 0.55 && money >= aBet + 2 * ANTE;
}
```
Well, it was this, or making a neural network and exporting it to C. Never actually used C before, but C++ is close enough to know all this.
Also, the controller's `Bot` struct is missing it's `opponentsMoney`.
] |
[Question]
[
I recently saw [this](https://esolangs.org/wiki/MarioLANG) language in a challenge and it's awesome. Does anyone have some tips for [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'")ing in it?
Your tips should be at least somewhat specific to MarioLANG.
Please post one tip per answer.
[Answer]
# Use the fall at the end for instructions
This is a pretty simple tip but many MarioLANG programs end something like this, ending with Mario falling down:
```
.....
=====
```
and this can be written instead as this:
```
....
===.
```
saving two bytes.
If your program has an elevator near an end like this you can often improve even further. This:
```
]!......
=#======
<
="
```
goes to this:
```
]!.
=#.
.
.
<.
=".
```
You do have to be careful with the last one though, since the added spaces to get to the final instructions can in many situations be more costly than just writing it largely on one line.
[Answer]
# Duplicate input
Sometimes, you will need multiple copies of a given input - here is a 27 byte snippet that will do this.
```
>[!
"=#
- )
( +
( )
!+<
#="
```
Alternate 39 byte horizontal version:
```
> [!
"=======#
!-((+)+)<
#======="
```
Before:
```
Memory Pointer: ˅
Cell : n 0 0
```
After:
```
Memory Pointer: ˅
Cell : 0 n n
```
] |
[Question]
[
In this variant of the [Four fours puzzle](http://en.wikipedia.org/wiki/Four_fours) your should use up to `x` `x's` (and no other number) and a defined set of operations to reach every number from 0 to 100. If `x = 4` then you can use up to four `4s` and this question becomes the classic four fours puzzle (except you can use up to four 4s rather than having to use exactly four of them). We assume `1 < x <= 9`.
In this version, only the following operators are allowed:
* Addition (`+`), Subtraction (`-`), Multiplication (`*`), Division (`/`). Note this is real division, so that `5/2 = 2.5`.
* Exponentiation (e.g. 4^4) as this would involve no extra symbols if written normally by hand.
* You can make new integers by concatenating `xs`. E.g. you can make the integers `4, 44, 444, 4444`.
You may also use parentheses to group numbers simply in order to control the order of evaluation of the operators. You can't for example combine parentheses with concatenation as in `(4/4)(4/4) = (1)(1) = 11`.
No other symbols may be used and standard order of operations applies.
Your program should generate, given an `x` in the defined range and an `n` between `0` and `100` inclusive, a correct solution for that input if it exists. Otherwise your code must output something to indicate no such solution exists.
You must be able to run your submission to completion on your machine for any input values of `x` and `n` in the allowed range. This is code golf, so shortest solution wins.
This old [related question](https://codegolf.stackexchange.com/questions/12063/four-fours-puzzle) uses more operators (and only 4s) and hence all numbers from 0 to 100 are solvable which won't be true for this challenge.
**Input and output**
Your code takes two integers `x` and `n` as input and should output a solution (or an indication there is no solution) in any human readable format you find convenient. Input `4 6` would mean "Using up to four 4s, make the number 6" for example. So if the input is `4 6` the output could be `(4+4)/4+4`.
[Answer]
# [Python 3](https://docs.python.org/3/), 265 bytes
```
def f(x,n):
for e in g(x,x-(x>7)):
try:
if eval(e)==n:return e
except:1
g=lambda x,d:{str(x)*-~i for i in range(d)}|{s%(a,b)for a in g(x,d-1)for b in g(x,d-a.count(str(x)))for s in'%s**%s (%s/%s) (%s+%s) (%s-%s) %s*%s %s/%s'.split()['**'in a+b:]}if d else{}
```
[Try it online!](https://tio.run/##rZHfaoMwFMbv8xQHhpjY2M3aP5vgnkMYu4hNdIJLJUmHxXav7pK4MmH0rleH3/nId87J153Mx0Gm48hFBRXuqSQZguqgQEAjobadPsb96464Phh1cgWaCsQXa7EgeS4zJcxRSRBWEf1edCZLUJ237LPkDHrKs0EbhXsSxd@N926ct2KyFpiTy3nQAWa0JE5i17E8Tnyj/Guw5f5wlAZPbsTL2sphoKMo0IAD/Rho4urit8auWtmqXgyXumsbg8lbGEWhdWaLMnu/2Hs4iFaL4TJ2qrEzKryiK0LQlVK6ndGaJskMNzTdzXBLN08z3NH1ZobPEz5c@cXz3QNAyDn6j3Mvi3z6NQQqH4obSSDny92Af1H4qTfyKKbdANQ5n2d5n2zsxtN56gc "Python 3 – Try It Online")
Works for *all* numbers in the [reference](https://arxiv.org/pdf/1502.03501.pdf) linked by Engineer Toast.
Runs up to `x=8` on tio, `x=9` takes a couple of minutes on my machine.
---
The function `g` returns a set of all combinations with at most `x` number of `x`'s. `f` then loops through them and returns the first which evaluates to the number `n`.
The number of possible values i found for each `x` are:
```
x possible numbers
------
2 5
3 17
4 35
5 56
6 83
7 101
8 101
9 101
```
All the numbers above can be generated from `(a+b)`, `(a-b)`, `(a+b)`, `a*b`, `a/b`, `(a/b)`, and `a^b`.
`a+b` and `a-b` do not give more numbers.
`a^b` is also only used once, as otherwise huge numbers are created (this is also verified in the reference document above)
---
An alternate version which short-circuits as soon as it finds a solution (not as golfed):
This is much faster as for `x=7..9` all numbers can be created.
# [Python 3](https://docs.python.org/3/), ~~338~~ 289 bytes
```
def f(x,n,d=-1):
d=[d,x][d<0];X=str(x);r=set()
for E in{X*-~i for i in range(d)}|{s%(a,b)for a in[0]*d and f(x,n,d-1)for b in f(x,n,d-a.count(X))for s in'%s**%s (%s/%s) (%s+%s) (%s-%s) %s*%s %s/%s'.split()['**'in a+b:]}:
try:e=eval(E)
except:e=-1
if e==n:exit(E)
r|={E}
return r
```
[Try it online!](https://tio.run/##TY/BboMwDIbvPEWkCZHQ0EEp7UaXY98BCXEITdiQqoCSdKKi7NWZYaPiZH3@ZPt3e7dfjYrHUcgKVbijigoWRCR1kGC5oF2Ri4@wOGXMWI07ctLMSIuJg6pGozOqVZ/5wU89Yw2INFefEgsyPHrjYk5LMikOKg8LXyCuxHII7kyunMaWFt9empuyOCOzM@A81/i@axB2zatryFQ3/zWYKmiws/S2pr3WkC/3fN@DtXxTpsUA3yCr76lk8ptf8RniI9ldZGuhFURAdYUkYyqVHUzPXj9Yfx4cpKW9aXhrfGl1DcEqvKM7QpwnxvSwxj2NojUnND6u@UCTcM1Huk/W/PbHC77POP4C "Python 3 – Try It Online")
] |
[Question]
[
## Introduction:
You are a worker, who is in charge of managing a set of bridges, connecting a square grid of "nodes":
```
N - N - N
| | |
N - N - N
| | |
N - N - N
```
(the grid here is 3 by 3, but they can be larger).
Each of the bridges has a set capacity from `1` to `10`, and each of the bridges has a number of cars over them, also from `1` to `10`.
* If a bridge has a higher capacity than the number of cars on that bridge, then it is considered "safe", and you can cross over it.
* If a bridge's capacity and number of cars going over it are equal, then it is considered "stable". It won't collapse, but you can't cross over it.
* If a bridge has a lower capacity than the number of cars on that bridge, then it is considered "collapsing", and you only have a limited amount of time to fix it.
When a bridge has `n` capacity and `m` cars, with `n` smaller than `m`, the time it takes to collapse is:
```
m + n
ceil( ----- )
m - n
```
You must take materials (and therefore reduce the bridge's capacity) from other bridges and arrive to those bridges on time to fix them! To get materials from a bridge, you must cross over it. For example, take this small arrangement:
```
A - B
```
The bridge between `A` and `B` (which we'll call `AB`) has `3` capacity, and let's say you're on `A`, and want to take `1` material. To take the material, simply cross from `A` to `B`.
*Note*: You don't have to cross the bridge multiple times to get multiple materials, you can take as much material as you want from a bridge in one go, as long as it doesn't cause the bridge to start to collapse.
Now, `AB` has `2` capacity, and you have `1` material on you. You may only cross over bridges that are "safe", though (or if you're fixing a bridge, which is explained in the next paragraph).
To fix a bridge, you must go over it, thereby depositing all materials needed to fix the bridge. For example, in the example above, if `AB` had `1` capacity and `2` cars currently on it, and you had `2` material on you, once you cross the bridge you will have `1` material, because that is all that's required to fix the bridge.
You must fully cross a collapsing bridge before the bridge collapses, otherwise it will break. Each crossing of a bridge takes `1` hour, and the time it takes for the bridge to collapse is shown in the formula above. For example:
```
A
|
B
|
C - D
```
In this example, if your starting node was `A`, and `CD` only had a "lifespan" of 2 hours, the bridge would collapse before you can get to it (crossing `AB` takes 1 hour, crossing `BC` takes another hour).
## Task:
Your task is to make a program that calculates, given a list of bridges, which are represented themselves as lists of two elements (first element is capacity, second element is cars on the bridge), whether or not it's possible to fix all of the bridges. The bridges work from top-to-bottom, left-to-right - so an input of
```
[[3 2] [3 2] [2 5] [5 1]]
```
means that the actual grid looks like this:
```
3
A --- B
| 2 |
3|2 2|5
| 5 |
C --- D
1
```
So `AB` has a capacity of `3` and `2` cars, `AC` has a capacity of `3` and `2` cars, `BD` has a capacity of `2` and `5` cars, and `CD` has a capacity of `5` and `1` car.
## Rules / Specs:
* Your program must work for, at least, `10 * 10` grids.
* Your program may accept the input as either a string with any delimiter, or a list of lists (see example I/O).
* Your program must output the same value for true for all true values, and it must output the same value for false for all false values.
* You can either submit a full program or a function.
## Example I/O:
```
[[5 5] [5 5] [1 1] [3 3]] => true
[[2 5] [2 2] [3 3] [1 2]] => false
[[3 2] [3 2] [2 5] [5 1]] => true
NOTE, you can take the input like this as well:
[[3, 2], [3, 2], [2, 5], [5, 1]] (Python arrays)
3,2,3,2,2,5,5,1 (Comma-separated string)
3 2 3 2 2 5 5 1 (Space-separated string)
```
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so shortest code in bytes wins!
[Answer]
# Python3, 560 bytes:
```
R=range
def V(b,x,y,X,Y):
try:return[(b[x][y],b[x+X][y+Y])]
except:return[]
def f(r):
K,w=0,int(len(r)**.5);b=[[K:=K+1for _ in R(w)]for _ in R(w)];e=dict(zip([l for x in R(w)for y in R(w)for l in V(b,x,y,0,1)+V(b,x,y,1,0)],r));q=[(e,0)]
while q:
e,c=q.pop(0);E=e.values()
if all(a>=b for a,b in E):return 1
if c<min(-(-((b+a)/(b-a))//1)for a,b in E if a<b):
for(j,k),(a,b)in e.items():
if a>b:
for J,K in e:
if(j,k)!=(J,K)and{j,k}&{J,K}:
for s in R(a-b):
Q=eval(str(e));Q[j,k][0]-=s;Q[J,K][0]+=s;q+=(Q,c+1),
return 0
```
[Try it online!](https://tio.run/##XVHBTuMwEL3nK8xlNUOmbdKq0qrF3LhsT@WwAlkWslNnyW5IUzdsGxDfXsZpAuzGh/Hze2@ex6nb5nFbzb7X/nS6ld5Uv1y0cbn4CZaO1NId3eMiEo1vF941z75SYNVRq1YT1/iOd/G9Rh0Jd8xc3Qwq3XXJwQf3ig4yoaJqoHQVH11ejue4tFKp1UKu4jTfevEgikrcwgH1v2jp5KbIGngpalClCORxIANov4IygOHqCaUYDyClBDV5xOVOKnABReLwWJRO7PiGwlEmd@N6W0OCyxvpxn9N@ez2gMwVuTBlCeZa2i7fkA05N9gPK9KzKLt6KioY8QIbG5yAHRnEySTFr66u3ZUN7yJCO/hNf5CAaWTajYvGPXFuR3faa3ved9k/aBW6uP6IBZ3/QgIzaKrNK8O3b6@M3gZNZ9yf38mM@uTuW0vHc8K@8eD4adaKzVoleiT3DLhHADGDXSxhTVmcIkWinzo51T780xyUmpOYaxIfNSWRhjojMdMaMfqUTnsJ1@mH5GyZ/iedfUqmvWVISYP09A4)
] |
[Question]
[
Wikipedia says about [Polar Coordinates](https://en.wikipedia.org/wiki/Polar_coordinate_system):
>
> In mathematics, the polar coordinate system is a two-dimensional coordinate system in which each point on a plane is determined by a distance from a reference point and an angle from a reference direction.
>
>
>
This seems perfect for describing hexagonal grids. Take the following hexagonal grid for example:
```
A B C
D E F G
H I J K L
M N O P
Q R S
```
Our reference point will be the center of the hexagon ('J'), and our reference angle will be to the top left corner of the hexagon ('A'). However, we'll describe the angle in terms of the number of *clockwise steps* around the outside of the hexagon from this point, not in angles. So we'll call it "Step number" instead of angle.
For example, 'C' is at (2, 2) because it has a radius of 2 (since it is two rings away from the center, 'J'), and an step number of 2 (2 clockwise steps forward from 'A'). Similarly, 'O' is at (1, 3), because it is one ring away from the center, and three clockwise steps forward from 'E' (which is on the reference angle).
For completeness, 'J' is at (0, 0), since you need 0 steps out and 0 steps clockwise to reach it.
Now, you can also describe a hexagonal with [Cartesian Coordinates](https://en.wikipedia.org/wiki/Cartesian_coordinate_system), but because of the offset this is a little weird. Just like with our polar coordinates, we will put the center at (0, 0). Each space takes up a coordinate also, so 'K' is at (2, 0), not (1, 0). This would put 'A' at (-2, 2), and 'O' at (1, -1).
# The challenge
Given polar hexagonal coordinates, output the same coordinates in Cartesian coordinates. You may take these coords, and the output the answer in any reasonable format. This means that you may reverse the order of the inputs if you like. This also means you could output the coords as (Y, X), but if you do, please mention this in your answer to avoid confusion.
You do not have to handle negative radii, but you may get negative angles, or angles that go more than a full revolution around the hexagon. For example, you may receive (1, 10), or (1, -2) as input. These would both correspond to 'N' in our previous hexagon. You do *not* have to handle non-integers for input.
# Sample IO
```
#Polar #Cartesian
(0, 0) (0, 0)
(1, 2) (2, 0)
(6, 0) (-6, 6)
(2, -3) (-3, -1)
(4, 23), (-5, 3)
(5, -3), (-8, 2)
(10, 50), (-20, 0)
(6, 10), (10, 2)
(8, 28), (0, -8)
(8, -20), (0, -8)
```
[Answer]
# JavaScript (ES6), 93 bytes
```
(r,d)=>[...Array(d+r*6)].map((_,i)=>x+="431013"[y+="122100"[i=i/r%6|0]-1,i]-2,x=y=-r)&&[x,-y]
```
Test snippet:
```
f=(r,d)=>[...Array(d+r*6)].map((_,i)=>x+="431013"[y+="122100"[i=i/r%6|0]-1,i]-2,x=y=-r)&&[x,-y]
g=([r,d],e)=>console.log(`f(${r},${d}):`, `[${f(r,d)}]`, "expected:", `[${e}]`)
g([0,0],[0,0])
g([1,2],[2,0])
g([6,0],[-6,6])
g([2,-3],[-3,-1])
g([4,23],[-5,3])
g([5,-3],[-8,2])
g([10,50],[-20,0])
g([6,10],[10,2])
g([8,28],[0,-8])
g([8,-20],[0,-8])
```
[Answer]
## JavaScript (ES6), 95 bytes
```
f=(r,t,x=-r,y=r,d=2,e=0)=>t<0?f(r,t+r*6):t>r?g(r,t-r,x+r*d,y+r*e,d+e*3>>1,e-d>>1):[x+t*d,y+t*e]
```
Explanation: The solution for a zero angle is simply `-r,r`, so we start at that point. If the angle is negative, we add on a whole hexagon and call ourselves recursively, otherwise we start walking around the hexagon with a `d,e=2,0` step. Where possible, we leap `r` such steps, then rotating the step using the formula `d+e*3>>1,e-d>>1` to progress to the next side. Finally we take any remaining steps to reach our destination.
] |
[Question]
[
A couple months ago, we had a [discussion on meta](http://meta.codegolf.stackexchange.com/q/7683/42545) about increasing the reputation awarded for upvotes on questions. Here's the basics of our current reputation system for votes:1
* A question upvote `U` is worth 5 reputation.
* An answer upvote `u` is worth 10 reputation.
* A question or answer downvote `d` is worth -2 reputation.
There have been many different suggestions for a new system, but the current most popular is identical to the above, but with question upvotes scaled to +10 rep. This challenge is about calculating how much more rep you would earn if this system were put into place.
Let's look at an example. If the voting activity was `UUUUuuuuUUUUUduuudUU`, then you'd earn 121 under the current system:
```
U x 4 x 5 = 20 = 20
u x 4 x 10 = 40 = 60
U x 5 x 5 = 25 = 85
d x 1 x -2 = -2 = 83
u x 3 x 10 = 30 = 113
d x 1 x -2 = -2 = 111
U x 2 x 5 = 10 = 121
Total: 121
```
But the same activity would earn 176 under the new system:
```
U x 4 x 10 = 40 = 40
u x 4 x 10 = 40 = 80
U x 5 x 10 = 50 = 130
d x 1 x -2 = -2 = 128
u x 3 x 10 = 30 = 158
d x 1 x -2 = -2 = 156
U x 2 x 10 = 20 = 176
Total: 176
```
You would gain **55 rep** from this scenario.
So far, calculating the changed rep isn't that hard; just count the number of `U`s and multiply by 5. Fortunately, the rep system isn't that simple: there is also a **rep cap**, which is the most reputation you can earn from votes in one UTC day. This is set to 200 on all sites.
Also, the rep cap applies in real time: if you have already earned 196 rep and you receive an answer upvote, you will now have 200 rep. If you get a downvote right after that, the 2 rep will be subtracted from 200, so you will have 198 rep.
With the voting activity `UUUuuuuUUUUuuuuUUUUUUUd`, you would earn 148 rep under the current system:
```
U x 3 x 5 = 15 = 15
u x 4 x 10 = 40 = 55
U x 4 x 5 = 20 = 75
u x 4 x 10 = 40 = 115
U x 7 x 5 = 35 = 150
d x 1 x -2 = -2 = 148
Total: 148
```
But you would earn 198 under the new system:
```
U x 3 x 10 = 30 = 30
u x 4 x 10 = 40 = 70
U x 4 x 10 = 40 = 110
u x 4 x 10 = 40 = 150
U x 7 x 10 = 70 = 200 (rep capped)
d x 1 x -2 = -2 = 198
Total: 198
```
Thus, the increase is **50 rep**.
## Challenge
Your challenge is to write a program or function that takes in a multi-line string and outputs the total rep that would be gained with the above algorithm. Each line counts as 1 UTC day, so the rep cap only applies once per line.
### Test cases
(One or more lines of input, followed by the output integer.)
```
UUUuudd
15
UUUuUUUUuUuuUUUUudUUUUuU
57
UUUuUUUUuUuuUUUUudUUUUuU
UUUuudd
72
uuuuuuu
uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu
uuuuuuuuuuuuuuuuuuuu
UUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU
UUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU
0
UUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUU
5
(empty string)
0
UUUuuuuuUUUuuUUUUUUuuuUUUuuUUUUuuuuUUUdddddddUU
4
UUUuuuuuUUUuuUUUUUUuuuUUUuuUUUUuuuuUUUdddddddUU
UuuUUUudUU
UUUUUUUUUuuuuuuUUUUUUuuUUUUUUuuuuuUUUUUUUUuUUUuuuuUUUUuuuUUUuuuuuuUUUUUUUUuuUUUuuUU
UUu
U
d
UU
UUUUUUUUUUUU
119
```
**This is code golf, so shortest code in bytes wins.**
Related challenges: [Calculate the bounded cumulative sum of a vector](https://codegolf.stackexchange.com/q/61684/42545), [Calculate your stack exchange reputation](https://codegolf.stackexchange.com/q/25047/42545)
1 This is a highly simplified version of the system. You also lose 1 rep for downvoting an answer, and there exist unupvotes, which [are weird and follow rules of their own](http://chat.stackexchange.com/transcript/message/27282054#27282054); and undownvotes, which [don't even have rules to follow](http://chat.stackexchange.com/transcript/message/25083191#25083191).
[Answer]
# Haskell, ~~98~~ 93 bytes
Thanks to BlackCap to golf this further. Now, I think to try lambda in later challenges, now.
```
x#'U'=x
_#'u'=10
_#'d'=(-2)
a&b=foldl1(\d g->min 200$d+a#g)
g=sum.map(\x->(10&x)-(5&x)).lines
```
The first 3 lines is the scoring, a&b is is the score, f is the difference and the g is the function sastifying the specification.
Usage:
```
g"UUUuuuuuUUUuuUUUUUUuuuUUUuuUUUUuuuuUUUdddddddUU" -- 4
```
[Answer]
## ES6, 104 bytes
```
s=>s.split`
`.map(l=>(g=U=>[...l].map(c=>(r+=eval(c))>200?r=200:0,r=0)|r,t+=g(10)-g(5)),u=10,d=-2,t=0)|t
```
Calculates the before and after rep for each line. My first use of `eval`!
[Answer]
# Lua, 196 Bytes
This program takes a single multi-line argument as input, and print the total difference in rep'
```
e,f,a=0,0,{u=10,U=10,d=-2}arg[1]:gsub(".-\n",function(s)x=0 y=0 s:gsub("[^\n]",function(c)t=x+a[c]x,t=t>199 and 200 or t,y+a[c]-(c<"V"and 5 or 0)y=t>199 and 200 or t end)e=e+x f=f+y end)print(e-f)
```
I assumed I am allowed to ask for a trailing new line in the input, if I'm not, here's a 204 Bytes solution that doesn't need it.
```
e,f,a=0,0,{u=10,U=10,d=-2}(arg[1].."\n"):gsub(".-\n",function(s)x=0 y=0 s:gsub("[^\n]",function(c)t=x+a[c]x,t=t>199 and 200 or t,y+a[c]-(c<"V"and 5 or 0)y=t>199 and 200 or t end)e=e+x f=f+y end)print(e-f)
```
### Ungolfed and explanations
```
a={u=10,U=10,d=-2} -- define the table containing the vote values
e,f=0,0 -- initialize the total sums of rep'
arg[1]:gsub(".-\n",function(s)-- iterate over each line
x=0 -- score by the new scoring method for this UTC day
y=0 -- score by the old method
s:gsub("[^\n]",function(c) -- iterate over each non new-line character
t=x+a[c] -- new score for today
x=t>199 and 200 or t -- reduce it to 200 if >=200
-- Do the same thing with the old scoring method
t=y+a[c]-(c<"V"and 5 or 0)-- if c=="U", this question vote gives only 5
y=t>199 and 200 or t
end)
e=e+x f=f+y -- sum the scores over multiple days
end)
print(e-f) -- output the difference
```
[Answer]
## Perl, ~~104~~ 91 + 2 = 93 bytes
```
sub f{200*$.>$_[0]?$_[0]:200*$.}for(/./g){$a=/d/?-2:10;$s=f$s+$a;$o=f$o+$a-5*/U/}}{$_=$s-$o
```
Requires the `-p` flag:
```
$ echo UUUuUUUUuUuuUUUUudUUUUuU | perl -p recalc.pl
57
$ echo "UUUuUUUUuUuuUUUUudUUUUuU
UUUuudd" | perl -p recalc.pl
72
```
Breakdown:
```
sub f {
# '$.' contains the line number (1, 2, ... n)
200*$. > $_[0] ? $_[0] : 200*$.
}
for(/./g){
$a= /d/ ? -2 : 10;
$s=f( $s + $a );
# /U/ returns `1` if true
$o=f( $o + $a - 5*/U/ )
}
}{ # Eskimo exit while loop (do this after the outer (from -p) iteration)
$_=$s-$o
```
] |
[Question]
[
Someone's given us a string, but all bracket-like characters have been changed into normal ones, and we don't know which, or even how many there were. All we know is that if `L1,L2,L3,...,LN` were different kinds of left brackets and `R1,R2,R3,...,RN` were different corresponding kinds of right brackets, all being distinct (2N distinct bracket characters), a string would be valid iff it is one of (+ is normal string concatenation):
* `L1+X+R1`,`L2+X+R2`,...,`LN+X+RN`, where `X` is a valid string,
* `X+Y`, where `X` and `Y` are valid strings,
* Any single character that is not a bracket character.
* The empty string
We know they started out with a valid string before they changed the brackets, and they didn't change them into any characters that already existed in the string. At least one pair existed for each bracket as well. Can you reconstruct which characters were originally left and right bracket pairs (find the `Li` and `Ri` following the given conditions)?
Output the pairs of characters that were brackets. For example, if `(){}[]` were actually bracket characters, you might output `(){}[]` or `{}[]()` or `[](){}`, etc. There may be multiple ways to do this for a string, you only need to return one such that there is no bracket assignment with more pairs (see examples). Note that the output string should always have an even length.
Examples:
`abcc` - `c` cannot be a bracket, since there is no other character with two occurrences, but `ab` can be a bracket pair, so you would output exactly `ab`.
`fffff` - any string with at most one character cannot have brackets, so you would return the empty string or output nothing.
`aedbedebdcecdec` - this string cannot have any brackets because there is 1 a, 2 bs, 3 cs, 4 ds, and 5 es, so no two characters occur the same number of times, which is a requirement to have brackets.
`abcd` - possible assignments are `ab`, `cd`, `abcd`, `cdab`, `adbc`, `bcad`, `ac`, `ad`, `bc` and `bd`, (as well as the empty assignment, which all of them have) but you must return one of the longest assignments, so you must return `abcd`, `cdab`, `adbc`, or `bcad`.
`aabbcc`,`abc` - these both have `ab`, `ac`, and `bc` as valid pairs. You must return one of these pairs, doesn't matter which.
`abbac` - a and b have the same character count, but they can't actually work, since one of them occurs to both the left and right of all occurrences of the other. Return nothing.
`aabcdb` - `cd` and `ab` are the exact two bracket pairs, so output either `cdab` or `abcd`.
`abcdacbd` - only one pair can be achieved at once, but `ab`,`ac`,`bd`,`cd`, and `ad` are all of the possible pairs you can return. No matter which pair you choose, it has an instance where a single other character is within it, which prohibits any other pairs, except in the case of `ad`, where the other pairs `bc` and `cb` are not possible alone either, and so can't be possible with `ad`.
This is code golf, so shortest code in bytes wins. Input is from STDIN if possible for your language. If it isn't possible, indicate the input method in your answer.
[Answer]
## Ruby, 373 bytes
```
i=gets.chomp
b=[*(i.chars.group_by{|x|x}.group_by{|x,y|y.size}.map{|x|s=x[1].size
x[1][0...s-s%2].map{|x|x[0]}*''}*'').chars.each_slice(2)]
puts [*[*b.size.downto(1).map{|n|b.combination(n).map{|t|[t*'',(h=Hash[t]
s=[]
o=1
i.each_char{|c|s.push(c)if h.keys.include?c
(o=false if s.empty?||!h[s.pop].eql?(c))if h.values.include?c}
o ?s.empty?: o)]}}.find{|x|x[0][1]}][0]][0]
```
This uses a golfed version of the stack parser [here](https://stackoverflow.com/a/25979589/1995101).
It can probably be simplified further, but I don't think my brain can handle any more.
**All test cases:** <http://ideone.com/gcqDkK>
**With whitespace:** <http://ideone.com/pLrsHg>
**Ungolfed (mostly):** <http://ideone.com/oM5gKX>
] |
[Question]
[
# A simple register calculator
This challenge involve a simple register calculator that works in the following way:
* It has some registers named `A,B,C,...,Z`, each of them can contain an integer, they are all initialized to `0`.
* It executes instructions of 3 characters: The first character of any instruction is one of `+,-,*,/,=` (add, subtract, multiple, divide, copy), the second character is the name of a register, and the third character is the name of a register or one of `0,1`. The meaning of the instruction should be quite clear, here some examples:
+ `+AB` means "set the value of the register `A` to the result of `A + B`", and similarly for `-AB,*AB,/AB`. The division `A / B` is done as in C.
+ `+A1` means "increment the register `A` of `1`", and similarly `-A1` decrements `A` of `1`.
+ `=AB` means "copy the value of `B` into the register `A`, similarly `=A0`, `=A1` sets `A` to `0`, `1`, respectively.
* It takes as input a string of consecutive instructions and it returns the result of the last operation, some examples:
+ Given `=A1+A1*AA` it returns `4`.
+ Given `+A1+A1=BA+A1*AB` it returns `6`.
+ Given `+A1+A1+A1*AA=BA-B1*AB` it returns `72`.
It is easy to write such a calculator in your preferred programming language, here an example in Python:
```
def compute(cmd):
opr = {"=": lambda x, y: y, "+": lambda x, y: x + y, "-": lambda x, y: x - y, "*": lambda x, y: x * y, "/": lambda x, y: x / y}
reg = {"0": 0, "1": 1, "A": 0, "B": 0, "C": 0, "D": 0, "E": 0}
ans = 0
i = 0
while i < len(cmd):
op = cmd[i]
r1 = cmd[i + 1]
r2 = cmd[i + 2]
reg[r1] = ans = opr[op](reg[r1], reg[r2])
i += 3
return ans
```
# The challenge
Write a program in any programming language that takes as input a positive integer `n` and returns a string of instructions that the calculator described above evaluates to `n`. For example, given `n = 13` a valid output for your program could be `+A1+A1+A1=BA+A1*AB+A1`. There are some restrictions:
* Standard [loopholes](https://codegolf.meta.stackexchange.com/questions/1061/loopholes-that-are-forbidden-by-default) are forbidden.
* The source code of your program should not exceed 1024 characters.
# How to compute your score
Run you program on each of the following 1000 random integers and sum the total number of operations in each output. For example, `+A1+A1+A1=BA+A1*AB+A1` consists of 6 operations, note that the copy instructions `=` are NOT operations and you should not count them.
```
3188162812
3079442899
158430004
2089722113
3944389294
2802537149
3129608769
4053661027
2693369839
420032325
2729183065
4214788755
680331489
3855285400
4233942695
4206707987
2357544216
457437107
2974352205
3469310180
3552518730
4140980518
2392819110
2329818200
662019831
2841907484
1321812679
2853902004
2272319460
133347800
1692505604
2767466592
3203294911
1179098253
2394040393
2013833391
3329723817
977510821
2383911994
1590560980
2045601180
1324377359
1586351765
1604998703
3016672003
3653230539
1466084071
2746018834
1056296425
3225491666
2113040185
918062749
3506683080
1809626346
3615092363
3944952222
4281084843
137951018
577820737
2304235902
4143433212
3183457224
294693306
1680134139
689588309
3657258008
2664563483
628899295
886528255
2539006585
2767153496
2742374091
2927873610
3725967307
2252643563
2716697503
1098010781
895335331
305272851
2605870648
3473538459
2739664556
2127000353
1774191919
3239195523
3120846790
3239808174
2588745068
3363081711
3105613110
3443977876
3233369379
949558184
2159450658
2930876206
1714955144
712790171
2472327763
3524210951
24655707
754856403
3220292764
708275816
2369186737
2485130017
404438291
1444836457
3936354990
3488645083
3881548856
1385884481
3750970390
1355492018
4246667593
791749996
1768738344
4014670055
3594141439
3111942631
2763557857
250495911
1635747286
1397550167
35044748
826650975
1249876417
2756572453
2014910140
1934230545
3893965263
1921703452
3479225211
232639352
1205471850
3147410912
4161504178
3896565097
336993337
898565456
1377983619
627866260
2972370545
2867339047
1517056183
3113779980
3650970589
105184832
3785364530
1892053898
2844419064
3581584776
773357885
1635965442
579795505
1082737975
4177210361
33726403
500010881
3770114942
1949554222
1808394144
2552929558
1679344177
4127951276
3703470385
2167661112
2012330972
3330988942
1625024662
4028645080
2268576559
1122753547
2801157103
2297468355
1248325165
3040195088
1505917132
1975920989
1331044994
1060195583
4053434779
1711909914
4165818150
1144987338
2582851730
159607843
4224173218
1122473605
4137009351
1859108466
140046799
3608276151
3755161872
1715239079
2210528921
4149673364
1683676925
3555426962
1903470380
1647594563
3992028616
831939758
1940233614
616234640
1033981562
989110726
3308560842
1362495884
2271865210
2497232294
2166547324
3134965769
1407359056
184303653
876724554
2257276636
1339263453
1505646879
4103125312
602341088
3411146479
4076735898
988798982
2881621101
3835638677
350262003
2083944362
793689959
1796614310
1722728365
1419496784
311460422
988078714
1191131280
685548336
2073528073
1341976830
1380421367
854492684
2349152
2760841279
3512440862
3492462961
955419776
134666263
1515743147
2802649615
343970838
5900423
3640581071
3690344254
33097513
3453017483
2702390881
2881748921
488817210
3179354661
3029418544
70044411
1956963103
1138956191
4099413570
113469500
2905850103
2267006431
990605747
2016466413
1406729175
457735529
1987564886
2555785209
2550678495
1324710456
1215784300
717815828
1894258881
2929394992
2793836849
1428923741
633224565
3516183531
221895161
2798935778
517240774
1906654368
3577752510
1412213936
978042011
741638677
1565247138
2333064112
2549498124
212184199
1539484727
3421514248
1918972072
933315257
1744663538
3834248593
1024107659
112895438
3354823598
3126205726
375723484
2105901209
287450971
669099946
1397558632
2606373532
125689337
3717502670
3258204174
1650199158
600374361
368452551
3686684007
3030953879
492919617
1203996049
863919924
2155962926
2878874316
1081637213
4025621502
969421830
906800845
732593812
3705231669
100350106
2062905253
2394749290
1537677769
2230238191
447840016
1442872240
2024556139
3023217942
4009927781
643221137
1779666873
3953330513
2024171749
795922137
997876381
1924314655
1177794352
3951978155
2649627557
1497778499
1718873438
1921453568
1327068832
2832829727
2225364583
1476350090
2647770592
3820786287
916013620
3982837983
3614316518
308109070
1800544679
2981621084
1428321980
4050055605
1492289670
2386916424
3191268731
580405899
2267245329
1732073940
1096029767
1295821464
3364564864
2652920150
3364522304
488005592
2192878399
160846995
218793067
300953008
3159368600
3645636269
2691580186
827223351
3050975392
1465133880
1478016997
1719998613
652363401
2555898614
4066532621
1765212455
34216921
1638964775
1371429240
838490470
82423487
1714800592
3494875381
3873346547
4054782046
3696936256
4275305812
2168667803
4160190912
3795501892
1459579204
3788779072
265527890
854488955
2942834006
2379627823
518232762
518434777
3944651255
3797616526
3707541025
322349517
474725696
3644506417
298197509
2568152353
2590844880
3117635513
1074315194
4084685556
2962342284
2653600388
3288534723
3794138452
1647860359
4009971876
2133083710
3370033103
47844084
1104447774
1945114365
3574343235
3780282459
3381199373
1018537272
1382098367
1412005134
1344062628
2346644176
722899092
2614932463
2145401890
827890946
255045026
1886847183
2717637818
1153049445
1367369036
2426902133
1836600086
3249356599
3406700718
2782602517
805660530
2582980208
2668716587
1318623475
3718765477
3906582528
2049615170
2266673144
693017899
1850804437
3662076224
1439399599
3609671497
3521926429
661675539
3211764017
3849411286
3961495122
3240515755
3110520252
3247223395
2601642984
531083777
1428656097
2621375427
1425006097
3346815151
1736182994
2749088925
3828456894
522766581
1596198864
1089234568
516631143
1714958540
550383692
2205580129
1129010921
2855807192
843448099
2537619198
2817077189
1862738454
1292393032
1867270512
3245153467
1330535377
63085178
476740794
3784629223
1469948976
2840691011
1501561593
2222500334
1417999206
1501666518
1146520258
853475958
688318779
2212745726
3697365636
4188412866
1971070414
2765322323
3338736319
4106229372
3547088973
3610171853
417218792
2645989082
2625322695
3788226977
866881900
3042410163
3339075441
1434921464
2037891551
4265507318
1488099724
573885128
528293886
863928770
2214944781
3913280213
3752689511
3519398632
549671367
662190591
3578320334
1609736323
1920189717
2049295962
1680309555
3056307661
237881083
1746281815
3988208157
2505692550
533953235
3859868829
3792904168
3181176191
764556169
78617399
3222196435
2366977555
608590681
303423450
559903926
1444205960
2795852572
3461738581
2509323146
2734638697
118860267
1918139288
2567665860
2153622033
3097512138
4224583193
1308314884
1348993134
3573313872
80532767
373807250
3963872687
1414605355
1390608957
1438723366
3335250816
3812365414
1257060108
1155935111
2101397457
1834783042
1751275025
1697354321
2932378401
1665717453
1378885897
3863913849
169333097
1073827664
777437131
3466174585
4046814722
2525749031
2116514103
2240001267
3455152569
579339098
2014028365
3808320943
1577950380
2691778801
3752766002
3849855789
1537004930
384431257
2179992010
36153591
4192751001
1804838630
987326618
4149586235
2231006803
3583701679
820347619
316668661
709355791
3570998394
1949820944
2602827205
4168457060
4281494037
3371936535
2794977651
2859282911
3673967898
13357998
1321990240
1432920498
2348123485
205633677
1467790392
3366396640
382875586
3791338683
478208002
2728443830
2837394277
3723656578
289818980
3607540282
1775363546
2183739548
4177115501
775276465
1690545788
1075449013
572714464
2769169223
3277515030
3206017211
763710358
2535539628
538656028
1428522787
2412864965
2447537924
3399886379
1955069748
73813115
2985639257
3129134081
2902917098
3832348869
2446124823
1520308572
2779582451
3152572003
284626848
2622927684
2243844449
2707184379
3996077339
1143205932
4249437886
4013946423
1243498130
2239561716
2454002725
3202102404
3489290520
568827898
2077682453
1973647425
2311090024
3452693414
566624799
1905493748
3381640023
3228957600
2097911855
3346084948
2492783447
2933529940
2933060277
509789087
4110089257
2789615392
2293641703
3346767700
2861425094
1325878754
2100601638
3154735442
1589556635
543727545
2077077585
2301440962
3562819978
3678224450
88375847
2286883432
810549767
4111034512
672827645
3538058849
3243887391
4260719631
3878976366
1173949115
522599614
2237854030
3700071391
3701211843
2474968151
1856102230
1612779479
417924004
1408725257
3663088753
1092263738
373569884
1394203899
2687184291
2200173651
16483411
2144831293
1953173328
2680701575
1891347549
594615324
2941482356
1349499420
2341998425
3246298001
3915604073
2598997329
2742107968
1706515316
3230227853
1698480626
3171621896
3553701103
3699504403
3264436517
789435265
1540974002
76880268
2021546521
228600347
3120127535
855819397
913492933
1706352147
3824217844
4254086533
4210176230
247387836
3028729765
1294455673
832399118
1989368151
3843532893
4058042419
4176223654
1871853736
2245388136
3396787616
453433399
3628835268
13531968
1038657709
2005262423
409396841
3236752715
504051173
1284135365
1498489066
1951495621
785956452
979254655
1255744440
2124184282
1791931889
2785197261
941345859
2272057653
105734226
1038331147
3859502227
1364397134
1151431380
3572487724
3440271596
3567083908
3969594482
2717167268
2070800249
565656056
2585323347
3710407107
1655322191
2871691151
1578274901
925898023
98152205
2387892947
3688205134
1060122118
3601926463
3963544592
2836575178
3517776876
1116673438
4141604495
3702313624
3321374643
3027449932
446202974
2704262583
1454829930
310100992
4167677094
4283752410
3749990846
3082431927
3668805960
4197104147
2921050366
40497657
1198947069
4265036060
3094866761
732821358
3734577383
3582534668
1453076357
881135315
3444396361
3113501566
2961866531
3235889511
2927326630
151940017
498024918
427292182
4276572621
2573590608
901394328
2351057309
1560851771
836443396
702781140
4143407241
3833119244
1092986235
3835147739
2801574120
2220928350
2773965488
1092717858
2314157136
4281370255
1044194898
4056801311
2672327460
2464844936
2964067147
535238874
34767265
4052881906
277239886
3205998707
4168364957
3390679324
3154285793
3493261782
1364027732
633131904
2306043313
253100060
3085422190
1571296680
1116733249
517969149
2063982173
1580514293
2306636650
211667764
43257052
2187912911
1419556982
2885452390
475014467
4276725894
2112535198
1381468052
3535769995
3030340194
2554618335
701632787
3621637286
200999835
2299787216
148189901
476612087
3139125858
1721355976
2863292989
270189306
1574116759
4001329945
616943685
3636040393
1361384267
1959022335
122277322
2067861043
2294386020
1121565222
1844367203
3119120617
1420612680
1541302975
3197481918
648483752
451388069
856130175
2960393334
988907653
1730735603
1640257249
1832729474
306034410
853922102
2001624344
3253510094
3906676405
37452680
3779097581
1958179154
2395885855
800614078
2085912
3020166783
2260099399
3490922778
2459139074
3886269878
3341685647
1050712773
59317986
3041690572
3236133509
2401182200
1535265086
1663785422
3664887088
3252400434
377629836
1024996414
1518007563
1821746700
1231613438
1709191483
2422047361
1393454235
2346354546
3263498417
3321719966
3652825361
948364811
371026554
2175702095
1880788290
4214724129
503657540
```
The same list of numbers [can also be found on Pastebin](http://pastebin.com/82iNkA7t).
The lower your score is, the better it is. Good luck!
**NOTES:**
* I choose random integers between 0 and 2^32-1, so that computations could be performed in C (unsigned long) or other languages without native support for arbitrary sized integers. However, be careful of overflows!
* When computing your score, check also that the output of your program is correct, it's easy to make errors.
* I wrote a script of 512 characters that got a score of 27782.
[Answer]
## Java, Total Score: 46009 operations
*Saved **2000** operations thanks to steveverrill and **1000** thanks to Bob!*
```
z->{String s=Integer.toBinaryString(z),r="=A1";for(int j=s.length()-1;j>=0;j--){if(s.charAt(j)=='1')r+="+CA";r+=j>0?"+AA":"";}return r;};
```
Test it with this full program:
```
public class Calculator {
public static void main (String[] args) {
A a = z->{String s=Integer.toBinaryString(z),r="=A1";for(int j=s.length()-1;j>=0;j--){if(s.charAt(j)=='1')r+="+CA";r+=j>0?"+AA":"";}return r;};
System.out.println(A.a(117));
}
public interface A {
void a(int c);
}
}
```
Caculates the strings based on the binary representations of the input numbers. Score calculated with this program:
```
public class Calculator
{
public static void main (String[] args) throws FileNotFoundException {
FileInputStream is = new FileInputStream(new File("test.txt"));
System.setIn(is);
int c = 0;
Scanner input = new Scanner (System.in);
while (input.hasNext()) {
c+=s(new Long(input.nextLine())).length()/3-3;
}
System.out.println(c);
}
public static String s(long z){String s=Long.toBinaryString(z),r="=A1";for(int j=s.length()-1;j>=0;j--){if(s.charAt(j)=='1')r+="+CA";r+=j>0?"+AA":"";}return r;}
}
```
[Answer]
Since the question got some votes, but only an answer was posted since so far, I post an answer (but not the 512 characters / 27782 score mentioned in the question).
# Python, Score: 35238
```
def f(n):
cmd = "=B1=C1+C1+C1"
while n > 0:
r = n % 3
n /= 3
if r == 1:
cmd += "+AB"
if r == 2:
cmd += "-AB"
n += 1
if n > 0:
cmd += "*BC"
return cmd
```
The idea is the same of GamrCorps's answer, but instead of using binary representation I used [balanced ternary representation](https://en.wikipedia.org/wiki/Balanced_ternary).
Why does it work better? Because a positive integer `n` has approximately `log(n)/log(2)` digits in base `2`, and on average half of them are `1`'s and the other half are `0`'s, hence about `(1/(2 log(2))) log(n) = 0.72... log(n)` instructions are required. In ternary balanced representation, `n` has about `log(n)/log(3)` digits, on average a third of them equal to `1`, and another third equal to `-1`, hence about `(2/(3 log(3))) log(n) = 0.60... log(n)` instructions are required.
] |
[Question]
[
# Write an interpreter for [2B](http://esolangs.org/wiki/2B)
I like [David Catt](http://esolangs.org/wiki/User:David.werecat)'s esoteric language 2B, having memory stored in a tape where each cell is a seperate tape of bytes (the 'subtape'). Write an interpreter for it!
## Language Specification
Official specification can be found [here](http://esolangs.org/wiki/2B#Instructions). In this specification, `"` means a number in the range `0-9` (`0` is interpreted as `10`), and `_` means a string of any length. Each cell stores a value in the range `0-255`, and overflow/underflow wraps around as it would a BF. (Thanks @MartinBüttner). To convert text to numbers `0-255`, use [ASCII codes](http://www.asciitable.com/). Because I can find no detail on this, I'm going to say that the tape length should be `255` minimum, but if you know otherwise please edit.
```
+-------------+----------------------------------------------------------------------------------------------------------------------------------------+
| Instruction | Description |
+-------------+----------------------------------------------------------------------------------------------------------------------------------------+
| 0 | Zeroes the current cell and clears the overflow/underflow flag. |
| { | If the current cell is zero, jump to the matching }. |
| } | A placeholder for the { instruction. |
| ( | Read a byte from the input stream and place it in the current cell. |
| ) | Write the value of the current cell to the console. |
| x | Store the value of the current cell in a temporary register. |
| o | Write the value of the temporary register to the console. |
| ! | If the last addition overflowed, add one to the current cell. If the last subtraction underflowed, subtract one from the current cell. |
| ? | Performs a binary NOT on the current cell. |
| +" | Adds an amount to the current cell. |
| -" | Subtracts an amount from the current cell. |
| ^" | Moves the subtape up a number of times. |
| V" | Moves the subtape down a number of times. |
| <" | Moves the tape left a number of times. |
| >" | Moves the tape right a number of times. |
| :_: | Defines a label of name _. |
| *_* | Jumps to a label of name _. |
| ~_~ | Defines a function of name _. |
| @_@ | Calls a function of name _. |
| % | Ends a function definition. |
| #_# | Is a comment. |
| [SPACE] | Is an NOP. |
| [NEWLINE] | Is treated as whitespace and removed. |
| [TAB] | Is treated as whitespace and removed. |
+-------------+----------------------------------------------------------------------------------------------------------------------------------------+
```
## Tests
```
+0+0+0+0+0+0+0+2)+0+0+9)+7))+3)-0-0-0-0-0-0-0-9)+0+0+0+0+0+0+0+0+7)-8)+3)-6)-8)-7-0-0-0-0-0-0)
```
Should output `Hello world!`
---
`+1:i:{()*i*}`
Sort of a `cat` program, just without a newline.
---
`+1:loop:{@ReadChar@*loop*}@PrintHello@@WriteAll@(~ReadChar~(x-0-3<2o^1>1+1>1%~PrintHello~+0+0+0+0+0+0+0+2)-1+0+0+0)+7))+3)+1-0-0-0-0-0-0-0-0)%~WriteAll~<1x:reverse:{<1v1>1-1*reverse*}o-1:print:{-1<1)^1>1*print*}%`
Should first accept a name, then, on press of `Return`, should output `Hello name` (where *name* is what was inputted).
Credit for that program goes to [David Catt](http://esolangs.org/wiki/User:David.werecat).
---
I'm working on a full test program.
## Rules
* [Standard loopholes](https://codegolf.meta.stackexchange.com/questions/1061/loopholes-that-are-forbidden-by-default) are forbidden
* Your interpreter must meet all the specifications, except for comments, which are not required.
## Scoring
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so fewest bytes wins!
* -10 bytes if your interpreter handles comments.
## Leaderboard
Here is a Stack Snippet to generate both a regular leaderboard and an overview of winners by language.
To make sure that your answer shows up, please start your answer with a headline, using the following Markdown template:
```
# Language Name, N bytes
```
where `N` is the size of your submission. If you improve your score, you *can* keep old scores in the headline, by striking them through. For instance:
```
# Ruby, <s>104</s> <s>101</s> 96 bytes
```
```
var QUESTION_ID=67123;function answersUrl(e){return"http://api.stackexchange.com/2.2/questions/"+QUESTION_ID+"/answers?page="+e+"&pagesize=100&order=desc&sort=creation&site=codegolf&filter="+ANSWER_FILTER}function getAnswers(){jQuery.ajax({url:answersUrl(page++),method:"get",dataType:"jsonp",crossDomain:!0,success:function(e){answers.push.apply(answers,e.items),e.has_more?getAnswers():process()}})}function shouldHaveHeading(e){var a=!1,r=e.body_markdown.split("\n");try{a|=/^#/.test(e.body_markdown),a|=["-","="].indexOf(r[1][0])>-1,a&=LANGUAGE_REG.test(e.body_markdown)}catch(n){}return a}function shouldHaveScore(e){var a=!1;try{a|=SIZE_REG.test(e.body_markdown.split("\n")[0])}catch(r){}return a}function getAuthorName(e){return e.owner.display_name}function process(){answers=answers.filter(shouldHaveScore).filter(shouldHaveHeading),answers.sort(function(e,a){var r=+(e.body_markdown.split("\n")[0].match(SIZE_REG)||[1/0])[0],n=+(a.body_markdown.split("\n")[0].match(SIZE_REG)||[1/0])[0];return r-n});var e={},a=1,r=null,n=1;answers.forEach(function(s){var t=s.body_markdown.split("\n")[0],o=jQuery("#answer-template").html(),l=(t.match(NUMBER_REG)[0],(t.match(SIZE_REG)||[0])[0]),c=t.match(LANGUAGE_REG)[1],i=getAuthorName(s);l!=r&&(n=a),r=l,++a,o=o.replace("{{PLACE}}",n+".").replace("{{NAME}}",i).replace("{{LANGUAGE}}",c).replace("{{SIZE}}",l).replace("{{LINK}}",s.share_link),o=jQuery(o),jQuery("#answers").append(o),e[c]=e[c]||{lang:c,user:i,size:l,link:s.share_link}});var s=[];for(var t in e)e.hasOwnProperty(t)&&s.push(e[t]);s.sort(function(e,a){return e.lang>a.lang?1:e.lang<a.lang?-1:0});for(var o=0;o<s.length;++o){var l=jQuery("#language-template").html(),t=s[o];l=l.replace("{{LANGUAGE}}",t.lang).replace("{{NAME}}",t.user).replace("{{SIZE}}",t.size).replace("{{LINK}}",t.link),l=jQuery(l),jQuery("#languages").append(l)}}var ANSWER_FILTER="!t)IWYnsLAZle2tQ3KqrVveCRJfxcRLe",answers=[],page=1;getAnswers();var SIZE_REG=/\d+(?=[^\d&]*(?:<(?:s>[^&]*<\/s>|[^&]+>)[^\d&]*)*$)/,NUMBER_REG=/\d+/,LANGUAGE_REG=/^#*\s*([^,]+)/;
```
```
body{text-align:left!important}#answer-list,#language-list{padding:10px;width:290px;float:left}table thead{font-weight:700}table td{padding:5px}
```
```
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script><link rel="stylesheet" type="text/css" href="//cdn.sstatic.net/codegolf/all.css?v=83c949450c8b"><div id="answer-list"> <h2>Leaderboard</h2> <table class="answer-list"> <thead> <tr><td></td><td>Author</td><td>Language</td><td>Size</td></tr></thead> <tbody id="answers"> </tbody> </table></div><div id="language-list"> <h2>Winners by Language</h2> <table class="language-list"> <thead> <tr><td>Language</td><td>User</td><td>Score</td></tr></thead> <tbody id="languages"> </tbody> </table></div><table style="display: none"> <tbody id="answer-template"> <tr><td>{{PLACE}}</td><td>{{NAME}}</td><td>{{LANGUAGE}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr></tbody></table><table style="display: none"> <tbody id="language-template"> <tr><td>{{LANGUAGE}}</td><td>{{NAME}}</td><td>{{SIZE}}</td><td><a href="{{LINK}}">Link</a></td></tr></tbody></table>
```
[Answer]
# Python2, ~~748~~ ~~736~~ ~~731~~ ~~709~~ ~~704~~ 691 bytes
This was a fun little challenge, I am sure I can make this code even shorter (maybe I'll do that at some point later).
```
from sys import*
w=stdout.write
p=open(argv[1],'r').read()
c,r,s,x,y,t,o=0,0,256,0,0,0,0
g=[[0]*s]*s
e=lambda d:p.find(d,c+1)
def h(i,j=0,k=0):global c,x,y;c+=1;n=1+(int(p[c])-1)%10;l=g[x][y]+n*i;g[x][y]=l%s;o=l/s;x=(x+n*j)%s;y=(y+n*k)%s
a="g[x][y]"
b="[p[c+1:i]]"
l={}
f={}
d={'0':a+"=0",'{':"if "+a+"<1:c=e('}')",'(':"i=stdin.read(1);"+a+"=ord(i)if i else 0",')':"w(chr("+a+"))",'x':"t="+a,'o':"w(chr(t))",'!':a+"+=o",'?':a+"=0if "+a+"else 1",'+':"h(1)",'-':"h(-1)",'^':"h(0,1)",'V':"h(0,-1)",'<':"h(0,0,-1)",'>':"h(0,0,1)",':':"i=e(':');l"+b+"=i;c=i",'*':"i=e('*');c=l"+b,'~':"i=e('~');f"+b+"=i;c=e('%')",'@':"i=e('@');r=i;c=f"+b,'%':"c=r"}
while c<len(p):
if p[c]in d:exec d[p[c]]
c+=1
```
This implementation requires for labels and functions to be declared (implemented) before being called. It works perfectly with the two tests given but it unfortunately doesn't work with the "SayHi.2b" program written by the author of the language (even after changing the order of declaration of the functions). I think this problem might have to do with the way I understood the tape and subtape system. When moving along the main tape, is the position on the corresponding subtape reset to 0? At the moment I am keeping the position on the subtape even when moving on the main tape.
Here is the more readable version:
```
#!/usr/bin/python
import sys
w=sys.stdout.write
p=open(sys.argv[1],'r').read()
c,r,s,x,y,t,o=0,0,256,0,0,0,0
# c is the current index in the program string
# r is the return index (for functions)
# s is the size of the tape, subtapes and modulo for ints (max int will be 255)
# x and y are the coordinates in the grid
# t is the temporary register
# o is overflow
g=[[0]*s]*s # initialise a grid 256x256 with 0
e=lambda d:p.find(d,c+1)
def n():global c;c+=1;i=int(p[c]);return i if i>0 else 10 # get the number specified
def h(i):j=g[x][y]+i;g[x][y]=j%s;o=j/s # handle addition and substraction
def m(i,j):global x,y;x=(x+i)%s;y=(y+j)%s # move current cell
a="g[x][y]" # string of current cell
b="[p[c+1:i]]" # key for label or function
l={} # dictionary of labels
f={} # dictionary of functions
d={'0':a+"=0",
'{':"if "+a+"<1:c=e('}')",
'(':"i=sys.stdin.read(1);"+a+"=ord(i)if i else 0",
')':"w(chr("+a+"))",
'x':"t="+a,
'o':"w(chr(t))",
'!':a+"+=o",
'?':a+"=0if "+a+"else 1",
'+':"h(n())",
'-':"h(-n())",
'^':"m(n(),0)",
'V':"m(-n(),0)",
'<':"m(0,-n())",
'>':"m(0,n())",
':':"i=e(':');l"+b+"=i;c=i",
'*':"i=e('*');c=l"+b,
'~':"i=e('~');f"+b+"=i;c=e('%')",
'@':"i=e('@');r=i;c=f"+b,
'%':"c=r",
'#':"c=e('#')"
}
while c<len(p): # loop while c is not EOF
# print c, p[c]
if p[c]in d:exec d[p[c]] # execute code kept as a string
c+=1 # increment index
```
Edit: Take into account the comments handling (-10 bytes), fixing an off by one error. This implementation doesn't support nested function calls (I could implement it if it is a required feature)
Edit2: Changed the handler function to do addition, substraction and cell movement. More lambdas! :D (The "more readable version" may be out of sync now)
Edit3: I just realized that handling comments costs me 5 bytes (taking into account the -10). So I just removed it, it's shame it now feels incomplete.
Edit4: moved definition of n from lambda to var inside the handler h()
] |
[Question]
[
The barbells at my gym look like this:
```
=========[]-----------------------[]=========
```
They can hold plates of five different sizes, 2.5 pounds, five pounds, ten pounds, 25 pounds, and 45 pounds:
```
.
. ! |
. ! | | |
| | | | |
' ! | | |
' ! |
'
```
For safety, we also add a clip `]` or `[` on the outside of all of our plates if there are any. The bar itself weighs 45 pounds. We always put the heaviest plates closest to the center, with no gaps between any plates, and put identical plates on both sides. We also always use the minimum number of plates possible, e.g. we never use two five-pound plates on one side instead of a single ten-pound plate. So if I want to lift 215 pounds, my bar looks like this:
```
. .
.!| |!.
!||| |||!
====]||||[]-----------------------[]||||[====
!||| |||!
'!| |!'
' '
```
Your code, a function or complete program, must take an integer from 45 to 575, always a multiple of 5, and output the bar that adds up to that weight. For example:
Input: `45`
Output (note there are no clips on an empty bar):
```
=========[]-----------------------[]=========
```
Input: `100`
Output:
```
! !
.| |.
======]||[]-----------------------[]||[======
'| |'
! !
```
Input: `575`
Output:
```
..... .....
.!||||| |||||!.
!||||||| |||||||!
]||||||||[]-----------------------[]||||||||[
!||||||| |||||||!
'!||||| |||||!'
''''' '''''
```
You can have trailing spaces on each line or not, but your output cannot have leading or trailing empty lines (the output for 45 should be one line, for 50 should be three lines, for 65 should be five lines, and so on.)
This is code golf, shortest code wins!
[Answer]
# Python 2, 295 bytes
```
i=input()-45
w=90,50,20,10,5;p=".|||||'"," !|||! "," .|||' "," !|! "," .|' "
a=[' '*46]
b=zip(*a*3+['='*9+'[]'+'-'*24+'[]'+'='*9]+a*3)
v=8
j=0
while i:
if i>=w[j]:i-=w[j];b[v]=b[-v-1]=p[j];v-=1
else:j+=1
if v<8:b[v]=b[10];b[-v-1]=b[9]
for l in zip(*b):
L=''.join(l).rstrip()
if L:print L
```
Builds the bar vertically, then rotates and prints non-empty lines.
[Answer]
# Pyth, 126 bytes
```
K[Z5TyT50 90)jfrT6.e::++J+?qk3\=dsm@bxKdhfqQ+45sTSSM^K8?qk3r"[]23-[]"9*27d_J"=\|""]|""\|=""|["c7s@L". !|='"jC"¾ª±À£¤¯aàI7"6
```
The source code contains unprintable characters, so here it is as an XXD dump:
```
0000000: 4b5b 5a35 5479 5435 3020 3930 296a 6672 K[Z5TyT50 90)jfr
0000010: 5436 2e65 3a3a 2b2b 4a2b 3f71 6b33 5c3d T6.e::++J+?qk3\=
0000020: 6473 6d40 6278 4b64 6866 7151 2b34 3573 dsm@bxKdhfqQ+45s
0000030: 5453 534d 5e4b 383f 716b 3372 225b 5d32 TSSM^K8?qk3r"[]2
0000040: 332d 5b5d 2239 2a32 3764 5f4a 223d 5c7c 3-[]"9*27d_J"=\|
0000050: 2222 5d7c 2222 5c7c 3d22 227c 5b22 6337 ""]|""\|=""|["c7
0000060: 7340 4c22 2e20 217c 3d27 226a 4322 04be s@L". !|='"jC"..
0000070: aa1f b1c0 a3a4 81af 61e0 4937 2236 ........a.I7"6
```
This code is **extremely slow**, to the point of no actual use. You can speed it up by about 1000 times by adding a `.{` (`set`) call in between, while keeping the code functionally equivalent. Here's a copy-paste friendly version of the resulting code:
```
K[Z5TyT50 90)jfrT6.e::++J+?qk3\=dsm@bxKdhfqQ+45sTS.{SM^K8?qk3r"[]23-[]"9*27d_J"=\|""]|""\|=""|["c7s@L". !|='"j96235640060099376576144045263159 6
```
[Answer]
# [Charcoal](https://github.com/somebody1234/Charcoal), 65 bytes
```
¹²[]P×=⁹≔⁻N⁴⁵θWΦ⟦⁵χ²⁰¦⁵⁰¦⁹⁰⟧¬›κθ«P|§⪪”{⊞⧴&β1←Z↶RΣ”,Lι→P[≧⁻⊟ιθ»‖B←
```
[Try it online!](https://tio.run/##TU9NT4NAED2XX7Hd02yymraRmNJ4qAdNk9I01XghPSAdYOJ2QViqRvztOMBBk53NfLx5816Sx1VSxKbr9hVZB/OFWnljKqOj5CJsjKNy6DzTGWuQd1KLpeLRuq4psxCSbWrY2LJxu@b8ihUoLW58/t4Z9JGTQQEPZBxPIl@L@UyLBYfPsZwdtdgVDh4rjHvAW7@llPj2Jv8uBy9YOUpio8XabewJP@GpNMQi27a91v2b6iFrp6xOasnXt2gzlwOpXuskLC4IwYGy3A3lH7mM5NCJy9HQgBldabEvSmYYrfx4B0wNJu6@caw1NV8QbDFlvq7zb/3u6mJ@AQ "Charcoal – Try It Online") Link is to verbose version of code. Explanation:
```
¹²[]P×=⁹
```
Print 12 `-`s, the `[]` and 9 `=`s. This comprises half of the bar. The cursor is left at the beginning of the `=`s.
```
≔⁻N⁴⁵θ
```
Subtract 45 from the input to allow for the weight of the bar.
```
WΦ⟦⁵χ²⁰¦⁵⁰¦⁹⁰⟧¬›κθ«
```
Filter a list of the possible weights of pairs of weights for those that are not greater than the input, and repeat while the list is not empty.
```
P|§⪪”{⊞⧴&β1←Z↶RΣ”,Lι
```
Split the string `|||.,|.,|!,||.,||!` on commas and select the piece corresponding to the heaviest possible weight, and print it both upwards and downwards. (Alternatively, it's possible to just print it upwards and reflect in the `¬` direction at the end; a number of variations have the same length.)
```
→P[
```
Print the clip (will get overwritten by the next weight if any).
```
≧⁻⊟ιθ»
```
Subtract the weight from the input.
```
‖B←
```
Reflect to complete the barbell.
] |
[Question]
[
I'm sure most of us have seen SQL results in a terminal, all neatly formatted into rows and columns. If you haven't, here's an example:
```
+----------+-----------+----------------+
| column 1 | column 2 | column 3 |
+----------+-----------+----------------+
| data | more data | even more data |
| etc | just goes | on and on |
+----------+-----------+----------------+
```
Your goal for this challenge is, given the columns and row data for a table, draw the table in this style. There should be a horizontal line at the top and bottom of the table, and one right below the header row. There should be vertical lines between every column, and one on both sides of the table. You should use pipes for vertical lines, hyphens for horizontal lines, and plusses for where they intersect.
## Specifics:
* The data can be entered via stdin, or as the argument to a function, but it must be in some form of string
* The data should be split by the string delimiter `;`
* The data will consist of only ASCII characters, is not quoted, and will not contain the delimiter.
* The first row of the data will be used for column headers
* The data will always have the same number of columns
* The input will always contain at least two rows (one header, one data). You do not have to handle empty sets.
* A trailing or preceding newline is permitted
* Each column should be as wide as the widest element, padding shorter elements on the right *(bonus -5% if you pad numbers on the left)*
* There should be 1 space of padding before and after the headers and data, except when the column is wider
* You are not allowed to use the actual `mysql` program to generate the table
* Standard loopholes apply
## Sample Input:
```
column 1;column 2;column 3
hello;world;test
longer data;foo;bar
```
## Output
```
+-------------+----------+----------+
| column 1 | column 2 | column 3 |
+-------------+----------+----------+
| hello | world | test |
| longer data | foo | bar |
+-------------+----------+----------+
```
## Scoring:
Lowest number of bytes wins, of course. -5% bonus for padding numbers on the left (see specifics).
[Answer]
# CJam, ~~67~~ 58 bytes
```
' qN/';f/ff+z_.{[z,):TS*'|+f.e|T'-*'++:T\(T@~T]}z{s_W=\N}/
```
Try it online in the [CJam interpreter](http://cjam.aditsu.net/#code='%20qN%2F'%3Bf%2Fff%2Bz_.%7B%5Bz%2C)%3ATS*'%7C%2Bf.e%7CT'-*'%2B%2B%3AT%5C(T%40~T%5D%7Dz%7Bs_W%3D%5CN%7D%2F&input=column%201%3Bcolumn%202%3Bcolumn%203%0Ahello%3Bworld%3Btest%0Alonger%20data%3Bfoo%3Bbar).
[Answer]
## JavaScript (ES6), 262 bytes
```
f=x=>{w=[],o=z=>y(`| ${z[m]((c,i)=>(c+' '.repeat(w[i]-c.length))).join` | `} |`),(d=x.split`
`[m='map'](r=>r.split`;`))[m](r=>r[m]((c,i)=>w[i]=Math.max(c.length,w[i]||0)));(y=console.log)(s=`+${w[m](c=>'-'.repeat(c+2)).join`+`}+`);o(d.shift());y(s);d[m](o);y(s)}
```
### Demo
Since it is ES6, this demo works in Firefox and Edge at this time. For some reason it does not work in Chrome/Opera even with experimental JavaScript features enabled.
```
// Snippet stuff
console.log = x => document.getElementsByTagName('output')[0].innerHTML += x + '\n';
document.getElementsByTagName('button')[0].addEventListener('click', () => {
f(document.getElementById('I').value);
});
// Actual code
f = x => {
w = [], o = z => y(`| ${z[m]((c,i)=>(c+' '.repeat(w[i]-c.length))).join` | `} |`), (d = x.split `
` [m = 'map'](r => r.split `;`))[m](r => r[m]((c, i) => w[i] = Math.max(c.length, w[i] || 0)));
(y = console.log)(s = `+${w[m](c=>'-'.repeat(c+2)).join`+`}+`);
o(d.shift());
y(s);
d[m](o);
y(s)
}
```
```
<p>
<textarea id=I cols=80 rows=15>column 1;column 2;column 3
hello;world;test
longer data;foo;bar</textarea>
</p>
<button type=button>Go</button>
<pre><output></output></pre>
```
] |
[Question]
[
### Introduction
After a long battle, you have managed to defeat a Sphinx in a contest of riddles. The Sphinx, impressed with your skill, wishes to give you a reward commensurate with your cleverness, and conjures into existence a strip of magical parchment divided into eight boxes, each containing a numeral.
"Crease the parchment," says the Sphinx, "such that the boxes overlap, and those boxes will merge either through addition or multiplication. When one box remains, its value will be your reward in gold coins."
### Task
You must write a program or function which takes as input a list/array/whatever of eight natural numbers, and returns/prints the maximum possible reward obtainable through a series of 'crease' operations.
### Mechanics
The 'crease' operation is performed on some number of cells, and with either `+` or `*` as the operator. The first n cells of the list are folded across and merged with their destination cells using the operator. Any cells which are not consumed in the merge operation are left unmodified.
Here is an example of creasing using n=3 cells:
[](https://i.stack.imgur.com/6BRPG.png)
using either addition, which would result in this:
[](https://i.stack.imgur.com/x7jtN.png)
or multiplication, which would result in this:
[](https://i.stack.imgur.com/7WrEs.png)
Note: For simplicity, creasing with fewer than 1 cell is disallowed, as is creasing with a number of cells greater than or equal to the length of the list. However, a list can by creased by more than half its cell count.
A list of 8 cells can be creased by 5, resulting in a new list of length 5:
`[0,1,2,3,4,5,6,7]` creased by 5 cells using the `+` operator would give `[9,9,9,1,0]`.
### Scoring
Standard code golf rules - the code which produces correct output and has the fewest number of bytes wins.
Bonus: If your code also returns/prints the sequence of crease operations which leads to the maximal reward, multiply your score by 0.8. Example output might look like:
```
crease 5 +
crease 2 *
crease 2 +
crease 1 *
```
### Examples
Test your code using these inputs and results, in the form of `input - maximum reward`:
```
[0, 1, 2, 3, 4, 5, 6, 7] - 7560
[0, 9, 0, 3, 2, 6, 1, 5] - 1944
[0, 1, 0, 3, 0, 2, 0, 4] - 36
[6, 0, 9, 1, 9, 0, 7, 3] - 11907
[0, 5, 2, 0, 1, 3, 8, 8] - 2560
```
[Answer]
# Pyth, 31 bytes
```
Le+bSyMsm,sMJ.T,_<bd>bdm*FkJtUb
```
This defines a function, `y`, which computes the crease value.
[Demonstration.](https://pyth.herokuapp.com/?code=Le%2BbSyMsm%2CsMJ.T%2C_%3Cbd%3Ebdm*FkJtUbyQ&input=%5B0%2C+5%2C+2%2C+0%2C+1%2C+3%2C+8%2C+8%5D&debug=0)
This uses the recusive method, taking the maximum of the score of every possible successor.
The base case of the recursion is implemented by concatenating the input to the sorted values of the possible successors, and then taking the end of the resultant list. If there is only 1 element in the input, there are no successors, and therefore the end of the list is the one element in the input.
[Answer]
## C#, 275 272 bytes
It's simply a recursive function that traverses every branch and returns the best score.
Indented for clarity:
```
using M=System.Math;
int F(int[]n){
int b=0,g,h,i=0,j,k,l=n.Length;
if(l<2)
return n[0];
for(;++i<l;){
int[]m=new int[k=M.Max(i,l-i)],o=new int[k];
for(j=0;j<k;j++){
m[j]=((g=i-j-1)<0?0:n[g])+((h=i+j)<l?n[h]:0);
o[j]=h<l&g>=0?n[g]*n[h]:m[j];
}
b=M.Max(b,M.Max(F(m),F(o)));
}
return b;
}
```
] |
[Question]
[
In [Chinese Checkers](https://en.wikipedia.org/wiki/Chinese_checkers), a piece can move by hopping over any other piece, or by making a sequence of such hops. Your task is to find the longest possible sequence of hops.
# Input
A sequence of 121 zeroes or ones, each representing a place on a board. A zero means the place is empty; a one means the place is occupied. Positions are listed from left to right; top to bottom. For example, the input of [this setup](https://upload.wikimedia.org/wikipedia/commons/1/18/Chinese_checkers_jump.svg) would be
```
1011110011000001000000000000000000000000100000000001000000000000000000000000000001000000000000000000000001000001100111111
```
Explanation:
>
> The top-most place is occupied by a green piece, so the first digit in the input is `1`. The second row has one empty position and then one occupied position, so `01` comes next. The third row is all occupied, so `111`. The fourth row has two empty and two occupied spaces (going left to right), so `0011`. Then comes five `0`'s, a `1`, and seven `0`'s for the next row, and so on.
>
>
>
Like in that setup, there is a corner pointing straight up. There may be any number of pieces on the board (from 1 to 121). Note that pieces of different colors are not represented differently.
# Output
The maximum length of a legal hop, using any piece on the board. You may not visit the same place more than once (including the starting and ending positions). However, you may hop over the same piece more than once. If there is no legal hop, output `0`. Do not consider whether there exists a legal non-hop move.
For example, the output to the setup described above is `3`.
Input and output may be done through stdin and stdout, through command-line arguments, through function calls, or any similar method.
# Test Cases
Input:
```
0100000010000000000000000100000000000000000000000000000001010010000000000000000000000101000000000000000000100000000100001
```
Output: `0` (no two pieces are next to each other)
---
Input:
```
0000000000111100000000011100000000011000000000100000000000000000000000000000000000000000000000000000000000000000000000000
```
Output: `1` (initial setup for one player in top-left corner)
[Answer]
## Perl, ~~345~~ 322
**Edit:** golfed, slightly.
More test cases would be nice, but for now it looks like it works. I'll add comments later if necessary. With newlines and indentation for readability:
```
$_=<>;
$s=2x185;
substr$s,(4,22,unpack'C5(A3)*','(:H[n129148166184202220243262281300')[$i++],0,$_
for unpack A.join A,1..4,13,12,11,10,9..13,4,3,2,1;
$_=$s;
sub f{
my(@a,%h)=@_;
$h{$_}++&&return for@a;
$-+=$#a>$-;
$s=~/^.{$a[0]}$_/&&f($+[1],@a)
for map{("(?=.{$_}1.{$_}(0))","(?<=(0).{$_}1.{$_}.)")}0,17,18
}
f$+[0]while/1/g;
print$-
```
[Answer]
# C,~~262~~ 260
**Golfed code** (debugging code and unnecessary whitespace removed. Changed from input via stdin to input via command line, and took advantage of the opportunity to declare variable i there. Latest edit: code moved into brackets of `for` loops to save two semicolons.)
```
t[420],j,l,x,y;f(p,d){int z,q,k;for(k=6;k--;t[q]&!t[p+z]?t[q]=0,f(q,d+1),t[q]=1:0)z="AST?-,"[k]-64,q=p+z*2;l=d>l?d:l;}main(int i,char**s){for(i=840;i--;x>3&y>5&x+y<23|x<13&y<15&x+y>13?i>420?t[i-420]=49-s[1][j++]:t[i]||f(i,0):0)x=i%20,y=i/20%21;printf("%d",l);}
```
**Explanation**
This relies on a 20x21 board which looks like this, initially filled with zeroes when the program starts (this ASCII art was generated by a modified version of the program, and as the `i` loop counts downwards, zero is in the bottom right corner):
```
....................
....................
...............#....
..............##....
.............###....
............####....
.......#############
.......############.
.......###########..
.......##########...
.......#########....
......##########....
.....###########....
....############....
...#############....
.......####.........
.......###..........
.......##...........
.......#............
....................
....................
```
Loop `i` runs through this board twice, using x and y to calculate whether a square actually belongs to the checkerboard or not (this requires 6 separate inequalities in x and y.)
If it does, the first time round it fills the squares, putting a `0` (falsy) for a `1` (occupied) and a `1` (truthy) for a `0` (unoccupied). This inversion is important, because all out-of-bounds squares already contain a 0, which means they resemble occupied squares and it is clear they can't be jumped into, without the need for a specific check.
The second time round, if the square is occupied (contains 0) it calls the function `f` that searches for the moves.
`f` searches recursively in the 6 possible directions encoded by +/-1 (horizontal), +/-20 (vertical) and +/-19 (diagonal) encoded in the expression `"AST?-,"[k]-64`. When it finds a hit, it sets that cell to a 0 (occupied) before calling itself recursively, then sets it back to 1 (empty) when the function is returned. The cell value must be changed before the recursive call to prevent hopping into that cell more than once.
**Ungolfed code**
```
char s[999]; //input string.
t[420],i,j,l,x,y; //t=board. i=board counter, j=input counter. l=length of longest hop found so far.
f(p,d){ //p=position, d= recursion depth.
//printf("%d,%d ",p,d); //debug code: uncomment to show the nodes visited.
int k,z,q; //k=counter,z=displacement,q=destination
for(k=6;k--;) //for each direction
z="AST?-,"[k]-64, //z=direction
q=p+z*2, //q=destination cell
t[q]&!t[p+z]? //if destination cell is empty (and not out of bounds) and intervening cell is full
t[q]=0,f(q,d+1),t[q]=1 //mark destination cell as full, recurse, then mark it as empty again.
:0;
l=d>l?d:l; //if d exceeds the max recorded recursion depth, update l
}
main(){
gets(s); //get input
for(i=840;i--;) //cycle twice through t
x=i%20, //get x
y=i/20%21, //and y coordinates
x>3&y>5&x+y<23|x<13&y<15&x+y>13? //if they are in the bounds of the board
i>420?
t[i-420]=49-s[j++] //first time through the array put 0 for a 1 and a 1 for a 0 ('1'=ASCII49)
:t[i]||f(i,0) //second time, if t[i]=0,call f().
//,puts("") //puts() formats debug output to 1 line per in-bounds cell of the board
:0;
printf("%d",l); //print output
}
```
] |
[Question]
[
**Closed**. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Add details and clarify the problem by [editing this post](/posts/16209/edit).
Closed 1 year ago.
[Improve this question](/posts/16209/edit)
I'm a bit of a romantic, I love taking my wife out to see the sunrises and sunsets in the place we are located. For the sake of this exercise let's say I don't have code that can tell me the time of either sunset or sunrise for whatever date, latitude and longitude I would happen to be in.
Your task, coders, is to generate the smallest code possible that takes a decimal latitude and longitude (taken in degrees N and W, so degrees S and E will be taken as negatives) and a date in the format YYYY-MM-DD (from Jan 1, 2000 onwards) and it will spit out two times in 24hr format for the sunrise and sunset.
e.g. For today in Sydney, Australia
```
riseset -33.87 -151.2 2013-12-27
05:45 20:09
```
Bonuses:
-100 if you can factor in elevation
-100 if you can factor daylight savings
The code MUST spit out times in the relevant time zone specified in the input based off the latitude and longitude OR in the client machine's own time zone.
[Answer]
I've spent quite some time writing this:
```
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from math import *
class RiseSet(object):
__ZENITH = {'official': 90.833,
'civil': '96',
'nautical': '102',
'astronomical': '108'}
def __init__(self, day, month, year, latitude, longitude, daylight=False,
elevation=840, zenith='official'):
''' elevation is set to 840 (m) because that is the mean height of land above the sea level '''
if abs(latitude) > 63.572375290155:
raise ValueError('Invalid latitude: {0}.'.format(latitude))
if zenith not in self.__ZENITH:
raise ValueError('Invalid zenith value, must be one of {0}.'.format
(self.__ZENITH.keys()))
self.day = day
self.month = month
self.year = year
self.latitude = latitude
self.longitude = longitude
self.daylight = daylight
self.elevation = elevation
self.zenith = zenith
def getZenith(self):
return cos(radians(self.__ZENITH[self.zenith]))
def dayOfTheYear(self):
n0 = floor(275*self.month/9)
n1 = floor((self.month + 9) / 12)
n2 = (1 + floor((self.year - 4*floor(self.year/4) + 2) / 3))
return n0 - (n1*n2) + self.day - 30
def approxTime(self):
sunrise = self.dayOfTheYear() + ((6 - (self.longitude/15.0)) / 24)
sunset = self.dayOfTheYear() + ((18 - (self.longitude/15.0)) / 24)
return (sunrise, sunset)
def sunMeanAnomaly(self):
sunrise = (0.9856 * self.approxTime()[0]) - 3.289
sunset = (0.9856 * self.approxTime()[1]) - 3.289
return (sunrise, sunset)
def sunTrueLongitude(self):
sma = self.sunMeanAnomaly()
sunrise = sma[0] + (1.916*sin(radians(sma[0]))) + \
(0.020*sin(radians(2*sma[0]))) + 282.634
if sunrise < 0:
sunrise += 360
if sunrise > 360:
sunrise -= 360
sunset = sma[1] + (1.916*sin(radians(sma[1]))) + \
(0.020*sin(radians(2*sma[1]))) + 282.634
if sunset <= 0:
sunset += 360
if sunset > 360:
sunset -= 360
return (sunrise, sunset)
def sunRightAscension(self):
stl = self.sunTrueLongitude()
sunrise = atan(radians(0.91764*tan(radians(stl[0]))))
if sunrise <= 0:
sunrise += 360
if sunrise > 360:
sunrise -= 360
sunset = atan(radians(0.91764*tan(radians(stl[1]))))
if sunset <= 0:
sunset += 360
if sunset > 360:
sunset -= 360
sunrise_stl_q = (floor(stl[0]/90)) * 90
sunrise_ra_q = (floor(sunrise/90)) * 90
sunrise = sunrise + (sunrise_stl_q - sunrise_ra_q)
sunrise = sunrise/15.0
sunset_stl_q = (floor(stl[1]/90)) * 90
sunset_ra_q = (floor(sunset/90)) * 90
sunset = sunrise + (sunset_stl_q - sunset_ra_q)
sunset /= 15.0
return (sunrise, sunset)
def sunDeclination(self):
sunrise_sin_dec = 0.39782 * sin(radians(self.sunTrueLongitude()[0]))
sunrise_cos_dec = cos(radians(asin(radians(sunrise_sin_dec))))
sunset_sin_dec = 0.39782 * sin(radians(self.sunTrueLongitude()[1]))
sunset_cos_dec = cos(radians(asin(radians(sunrise_sin_dec))))
return (sunrise_sin_dec, sunrise_cos_dec,
sunset_sin_dec, sunset_cos_dec)
def sunHourAngle(self):
sd = self.sunDeclination()
sunrise_cos_h = (cos(radians(self.getZenith())) - (sd[0]* \
sin(radians(self.latitude))) / (sd[1]* \
cos(radians(self.latitude))))
if sunrise_cos_h > 1:
raise Exception('The sun never rises on this location.')
sunset_cos_h = (cos(radians(self.getZenith())) - (sd[2]* \
sin(radians(self.latitude))) / (sd[3]* \
cos(radians(self.latitude))))
if sunset_cos_h < -1:
raise Exception('The sun never sets on this location.')
sunrise = 360 - acos(radians(sunrise_cos_h))
sunrise /= 15.0
sunset = acos(radians(sunrise_cos_h))
sunset /= 15.0
return (sunrise, sunset)
def localMeanTime(self):
sunrise = self.sunHourAngle()[0] + self.sunRightAscension()[0] - \
(0.06571*self.approxTime()[0]) - 6.622
sunset = self.sunHourAngle()[1] + self.sunRightAscension()[1] - \
(0.06571*self.approxTime()[1]) - 6.622
return (sunrise, sunset)
def convertToUTC(self):
sunrise = self.localMeanTime()[0] - (self.longitude/15.0)
if sunrise <= 0:
sunrise += 24
if sunrise > 24:
sunrise -= 24
sunset = self.localMeanTime()[1] - (self.longitude/15.0)
if sunset <= 0:
sunset += 24
if sunset > 24:
sunset -= 24
return (sunrise, sunset)
def __str__(self):
return None
```
Now it's not yet functional (I screwed up some calculations) - I'll come back to it later (if I'll still have the courage) to [complete it / comment it](http://williams.best.vwh.net/sunrise_sunset_algorithm.htm).
Also, some interesting resources that I found while researching the subject:
* [How to compute planetary positions](http://stjarnhimlen.se/comp/ppcomp.html)
* [How to adjust sunrise and sunset times according to altitude?](https://photo.stackexchange.com/questions/30259/how-to-adjust-sunrise-and-sunset-times-according-to-altitude)
* [How To Convert a Decimal to Sexagesimal](http://geography.about.com/library/howto/htdegrees.htm)
* [When is the right ascension of the mean sun 0?](https://physics.stackexchange.com/questions/46700/when-is-the-right-ascension-of-the-mean-sun-0)
* [How do sunrise and sunset times change with altitude?](http://curious.astro.cornell.edu/question.php?number=388)
* [What is the maximum length of latitude and longitude?](https://stackoverflow.com/questions/15965166/what-is-the-maximum-length-of-latitude-and-longitude)
* [Computation of Daylengths, Sunrise/Sunset Times, Twilight and Local
Noon](http://www.sci.fi/~benefon/sol.html)
* [Position of the Sun](http://www.stargazing.net/kepler/sun.html)
] |
[Question]
[
Let's call a non-empty list of strings a ***mesa*** if the following conditions hold:
>
> 1. Each listed string is non-empty and uses only characters that occur in the first string.
> 2. Each successive string is exactly one character longer than the preceding string.
> 3. No string in the list is a [subsequence](http://en.wikipedia.org/wiki/Substring#Subsequence) of any other string in the list.
>
>
>
The term "mesa" is from visualizing like this (where the `x`s are to be various characters):
```
xx..x
xx..xx
xx..xxx
.
.
.
xx..xxx..x
```
NB: It's a mathematical fact that only finitely many mesas begin with a given string. Note the distinction between *subsequence* vs. *substring*; e.g., 'anna' is a subsequence (but not a substring) of 'banana'.
### Challenge:
* Write the shortest program that takes an arbitrary non-empty alphanumeric input string and outputs the number of mesas that begin with that string.
### Input (stdin):
* Any non-empty alphanumeric string.
### Output (stdout):
* The number of mesas that begin with the input string.
### Scoring:
* The winner is the program with the least number of bytes.
### Example mesas
Only one mesa starts with `a`:
```
a
```
Only one mesa starts with `aa`:
```
aa
```
Many mesas start with `ab`:
```
ab ab ab ab (and so on)
baa aaa bbb
bbba bbaa
baaaa
aaaaaa
```
[Answer]
## GolfScript (106 103 chars)
```
n-..&1/:Z;]]0,\{.@+\{['']:E+.-2=,)E\{{`{+}+Z/}%}*{:x`{\1,+\{1$(@={\}*;}/0=!}+1$?!{.);[x]+\}*}/;}%.}do;,
```
Somewhere in the heart, of course, is some code from [Is string X a subsequence of string Y?](https://codegolf.stackexchange.com/questions/5529/is-string-x-a-subsequence-of-string-y)
[Answer]
### Ruby, 142 characters
```
m=->l{[*l[0].chars].repeated_permutation(l[-1].size+1).reduce(1){|s,x|l.any?{|y|x*''=~/#{[*y.chars]*'.*'}/}?s:s+m[l+[x*'']]}}
p m[[gets.chop]]
```
This algorithm is constructive, i.e. it builds all possible mesas for the input string and counts them. It makes the program really, really slow - but hey, it is codegolf.
Example runs:
```
> a
1
> aa
1
> ab
43
```
] |
[Question]
[
## Background
*Flow Free* is a series of puzzle games whose objective is to connect all the same-colored pairs of dots on the grid. *Flow Free: Warps* introduces the "warping" mechanic: a line connecting two dots can go through the border of the grid, which makes it re-enter through the opposite side of the grid (torus topology).
The following is an in-game screenshot of an initial grid and its complete solution, so that the readers can get some feel of the game.
 
Due to the warping nature, many of the lines should be drawn in multiple finger strokes. As in the screenshots, the game shows one-cell-wide extra border around the main grid whose cells act as "shadow" of the actual cells on the opposite side. The player can make any kind of moves on the shadow cells just like on the cells on the main grid.
The following shows the relationships between the shadow cells and their corresponding main cells on a 5x5 grid. Note that the shadow corner cells are also functional.
```
E5 | E1 E2 **E3 E4 E5** | **E1**
---+----------------+---
A5 | A1 A2 **A3** A4 A5 | A1
B5 | **B1 B2 B3** B5 | B1
C5 | C1 C5 | C1
D5 | D1 D5 | D1
E5 | E1 E2 E3 E4 E5 | E1
---+----------------+---
A5 | A1 A2 A3 A4 A5 | A1
```
For example, the path `B1 B2 B3 A3 E3 E4 E5 E1` can be drawn in one finger stroke by starting at main B1 and going `>>^^>>>`, finishing at the top right corner shadow E1.
Additionally, the game has a convenience feature: if you drop your finger at the cell (orthogonally) adjacent to the destination cell, the line is auto-connected with it. For example, if the destination of the above path is D1 instead, drawing the line through B1 to E1 is enough to complete the line, so the path still takes one finger stroke. But this feature only works between two cells adjacent *when only the main cells are considered*, e.g. dropping your finger at B5 (either main or shadow) won't auto-connect to B1.
Under these mechanisms, every single line shown in the above screenshot takes just one finger stroke. Note that you can start at either side of the line, and you can start or extend the line at any equivalent cell (out of the main and shadow cells).
To be precise, the player can do one of the following actions in one finger stroke:
* First stroke: Start drawing a line from one of the two dots, and draw it as far as possible, and release.
* Second and subsequent strokes: start drawing at the cell (or any of its shadows) where the last stroke stopped, and extend the line as far as possible, and release.
## Challenge
Given the description of a line on a grid of *Flow Free: Warps*, determine how many finger strokes will be needed to complete the line.
The line can be taken as input in a suitable, clear format. If the input is `B4 - B1 - B2 - A2 - D2` on a 4x4 grid, the following (and the respective equivalents according to Default I/O) are allowed:
* An ordered list of coordinates: `[(2, 4), (2, 1), (2, 2), (1, 2), (4, 2)]`
* A 2D grid where the path is marked with successive integers: `[[0, 4, 0, 0], [2, 3, 0, 1], [0, 0, 0, 0], [0, 5, 0, 0]]`
If you want to use a different input format, please ask in comments.
The line will always be valid in the following sense:
* It has a well-defined start cell and an end cell.
* Each adjacent pair of cells within the path are orthogonally adjacent on the grid, potentially through the border.
You can further assume the grid is rectangular and has at least 4 rows and 4 columns. The grid may be non-square.
You are *not* allowed to assume that the path does not touch itself. Many levels in the game contain some thin walls, which make some paths touch themselves by going through both sides of such walls.
Standard [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'") rules apply. The shortest code in bytes wins.
## Test cases
Since a line on a grid can be represented in multiple different ways, the test cases are presented in a visually clear style.
```
Input:
[[ 1, 2, 3, 4 ],
[ 8, 7, 6, 5 ],
[ 0, 0, 0, 0 ],
[ 0, 0, 0, 0 ]]
Output: 1
Input:
[[ 1, 2, 0, 0 ],
[ 0, 0, 0, 0 ],
[ 7, 8, 5, 6 ],
[ 0, 3, 4, 0 ]]
Output: 1 (start at bottom shadow of 1 and release finger at shadow 7)
Input:
[[ 0, 0, 0, 0 ],
[ 3, 4, 1, 2 ],
[ 6, 5, 8, 7 ],
[ 0, 0, 0, 0 ]]
Output: 2
Input:
[[ 0, 0, 0, 0 ],
[ 3, 4, 1, 2 ],
[ 6, 5, 0, 7 ],
[ 0, 0, 0, 0 ]]
Output: 1 (start at shadow 7 and release finger at shadow 2)
Input:
[[ 7, 8, 9, 0, 0, 0 ],
[ 0, 0, 0, 1, 2, 3 ],
[ 5, 0, 0, 0, 0, 4 ],
[ 6, 0, 0, 0, 0, 0 ]]
Output: 2 (first stroke can only go to 1..7 or 9..3)
Input:
[[ 0, 0, 4, 5, 0, 9 ],
[ 0, 0, 0, 6, 7, 8 ],
[ 0, 1, 0, 0, 0, 0 ],
[ 0, 2, 3, 0, 11, 10 ]]
Output: 1 (start at shadow 11 and release at shadow 2)
Input:
[[ 0, 0, 5, 0, 9, 0,15, 0,19 ],
[24,25, 6, 7, 8, 0,16,17,18 ],
[23, 1, 0, 0, 0, 0, 0, 0, 0 ],
[22, 2, 3, 0,11,12,13, 0,21 ],
[ 0, 0, 4, 0,10, 0,14, 0,20 ]]
Output: 5
```
[Answer]
# JavaScript (ES7), 194 bytes
Expects `(list, width, height)`, where `list` is an ordered list of 0-indexed coordinates.
```
(p,w,h)=>(m=g=([c,...p],N,X=-3,Y=X)=>1/X/Y?c?[0,1,2,3].map(k=>g(p,(X-([x,y]=c,P=k&1?x?~x+w?g:-1:w:x))**2<2&(Y-(Q=k&2?y?~y+h?g:-1:h:y))**2<2|!(p+p||k)?N:-~N,P,Q)):N>m?0:m=N:0)(p)|g(p.reverse())|m
```
[Try it online!](https://tio.run/##bY9Nk5pAEIbv/IrORWfWAZnxmw1ySo7Ubu1Fi@VAEJEoHwHXhYrxr5ueEXU3lWKq6H7ft5@e@Rkcgiosk2KvZ/kqOq/tMynYO9tQe05SO7aJFzLDMAqfuWxh6wO2tBfo8f6iv3RCxzMZZ4INfCMNCrK15zGOk4VOvJo1vh2yJ3vb4U7tnOreuxNbOrferZrShwfxVXTIUifPGBBO45ya3uYS2FhNGzh@IUWvOB631HEt/eSyJ/ZMqeXOU8e0Utu1TEoKesSdRhkdorKKCKXH9FxGv96SMiLdddWlaAWr78kuemmykJjU2Ocv@zLJYkKNqtgle9J9zV4zDK7z8lsQbkgF9hx@awBxmazAhuqew5R8qEpUBmLSG6UPvf7Fdd/SH1FJ6SMiimC/QYTnP7a82xZSMmioBJV37cCgVtoBOh0gcto7gA7cl5AaJ3x6AYd5VuW7yNjlMVmrIFN8z/SNXZTF175t5NAfeuYgYABDbQoTGMNIM0F9t78mAx@FCUxhBGPscUwGroZsMawhBSOTO@F/AfNjQCJnn/aqW2kjaCN4v/GtVkT8Iw1Bspi1Ap4x4DtgKgV@1eSRggC8soRz4AhprRahDFXzmSaGIEY3mBLHwCfAp5oY/EO@rxDi8w4BXNWCX3cNlaVqrmph/gU "JavaScript (Node.js) – Try It Online")
### How?
As illustrated below, there are up to 4 distinct ways of selecting some cells in the grid: the original position **P** and 3 shadow positions **S**.
```
. | . . . | .
---+-------+---
. | P . . | S
. | . . . | .
. | . . . | .
---+-------+---
. | S . . | S
```
The loop `[0,1,2,3].map(k=>...)` attempts to do one recursive call per possibility. However, if a given shadow is invalid, at least one of the coordinates will be set to a non-numeric value, causing the search to be aborted early thanks to the test `1/X/Y`.
We keep track of the current number of strokes in `N` and the minimum number of strokes in `m`.
If the last position used is not a shadow, the corresponding stroke is never counted, even if it's not adjacent to the penultimate position. The test is `|!(p+p||k)`.
Two searches are executed: from first to last point and from last to first point.
] |
[Question]
[
# Challenge
## Premise
Consider a mosaic of \$m\times n\$ tiles, in \$k\$ unique colours designated by integers. Example (\$3\times6\$, four colours):
```
4 1 3 2 4 2
1 2 4 2 1 3
4 3 2 1 4 4
```
My poor man's mirror is a pane of glass of width \$\sqrt{2}\cdot\min(m,n)\$. I stand it diagonally on the mosaic, like so:
```
4 1 3 M 4 2
1 2 M 2 1 3
4 M 2 1 4 4
```
For this example I can pretend it reflects exactly two full tiles:
```
x 1 x M x x
x 2 M x x x
x M 2 1 x x
```
No matter what diagonal I choose, this is the **greatest number** of full tiles I can fake-reflect. Yay.
## Task
Input: an integer matrix of \$m\$ rows and \$n\$ columns where \$2\leq m\leq1000,2\leq n\leq1000\$. The number of unique values is \$k\$ where \$3\leq k\ll mn\$.
Output: three integers, in any format. The first and second respectively represent the row coordinate and column coordinate of the matrix element ('mosaic tile') at the **left** end of the 45-degree diagonal where the fake mirror should be placed for 'best effect', effectiveness being defined as shown above. The third integer is 0 or 1, respectively meaning a rising (bottom left to top right) or falling (top left to bottom right) diagonal.
For clarity's sake, here are some simple test cases.
### Example 1
Input:
```
4 1 3 2 4 2
1 2 4 2 1 3
4 3 2 1 4 4
```
Output: `3 2 0`
### Example 2
Input:
```
3 6
4 7
5 8
1 2
2 1
```
Output: `4 1 1` or `5 1 0` (not both)
As you can see, **a unique solution isn't guaranteed**.
### Example 3
Input:
```
2 7 4 10 7 8 9 5 6 4 2 4 10 2 1 7 10 7 2 4 10 10 8 7
6 5 6 2 2 3 6 1 6 9 7 2 10 3 4 7 8 8 3 7 1 8 4 2
3 3 7 6 10 1 7 9 10 10 2 6 4 7 5 6 9 1 1 5 7 6 2 7
7 10 3 9 8 10 9 3 6 1 6 10 3 8 9 6 3 6 2 10 1 2 8 1
7 7 8 1 1 6 4 8 10 3 10 4 9 3 1 9 5 9 10 4 6 7 10 4
1 10 9 7 7 10 3 3 7 8 2 2 4 2 4 7 1 7 7 1 9 9 8 7
5 9 5 3 8 6 5 7 6 7 2 7 9 9 7 10 8 8 7 3 5 9 9 10
9 3 8 2 9 2 1 3 6 3 8 5 7 10 10 9 1 1 10 2 5 1 6 9
8 7 6 2 3 2 9 9 9 7 9 5 8 3 8 2 2 5 2 2 10 10 3 5
7 1 1 2 3 2 10 1 2 10 3 3 2 1 4 2 5 6 10 9 6 5 3 8
8 9 5 2 1 4 10 6 8 6 9 10 10 8 1 6 10 6 4 8 7 9 3 5
8 1 5 7 1 8 7 5 8 6 4 5 10 1 6 1 4 4 10 7 6 3 3 6
```
Output: `1 10 1`
## Edit - indexing
The example outputs are 1-indexed, but **0-indexing is allowed**.
# Remarks
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so fewest bytes wins.
* [Standard rules](https://codegolf.meta.stackexchange.com/questions/2419/default-for-code-golf-program-function-or-snippet/), [I/O rules](https://codegolf.meta.stackexchange.com/questions/2447/default-for-code-golf-input-output-methods) and [loophole rules](https://codegolf.meta.stackexchange.com/questions/1061/loopholes-that-are-forbidden-by-default) apply.
* If possible, link an online demo of your code.
* Please explain your code.
[Answer]
# [Charcoal](https://github.com/somebody1234/Charcoal), 91 bytes
```
≔⟦⟧θWS⊞θI⪪ι ≔L§θ⁰η≔⊖⌊⟦Lθη⟧ζF⁻LθζF⁻ηζF²⊞υ⟦Σ⭆⊕ζ⭆⊕ζ⁼§§θ⁺ι⎇λμ⁻ζμ⁺κξ§§θ⁺ι⎇λξ⁻ζξ⁺κμ⎇λι⁺ιζκλ⟧I✂⌈υ¹
```
[Try it online!](https://tio.run/##jVE9b4QwDN35FdZNjpRKhbJ1OvU6nFQkJLohhohLj6ghx0fSUv48dQAVOlTqlPj5@dnPLivRlTehp@nY9@pqMC84tOwx@KyUloBn0zib2U6ZKzIGqesrbDk8id5i1mhlUXE4wIExqlklXqS52gqP9mwucvD0e8Y4VBvjJMtO1tJYecFEGVW7GvO1rPXUwheMVPB268BTXI@7/Eij7DLVDonWIR2HPCPZZfZENGRlazqSyN@Z59YJ3f8Y2BlJNbUjx6@yM6L7Qs2h5rBMMdKf1sBW1juHwQf/Uxl2KsNvlVnUAzu62kRGnyKaLmhdKVmyuFxHq1JiIoZ5u45IoT/SNMUQwgNEEEMUhMvrkSCe0ZDiOJjuPvQ3 "Charcoal – Try It Online") Link is to verbose version of code. 0-indexed. Explanation:
```
≔⟦⟧θWS⊞θI⪪ι
```
Input the mosaic. (These 12 bytes could be avoided by requiring the input to be in JSON format, but I was too lazy to punctuate the example.)
```
≔L§θ⁰η
```
Get the width of the mosaic.
```
≔⊖⌊⟦Lθη⟧ζ
```
Get the inner size of the mirror, i.e. the distance from the first to the last character of the mirror in terms of diagonal steps.
```
F⁻Lθζ
```
Loop over the possible row(s) of the top left corner of the mirror's enclosing square.
```
F⁻ηζ
```
Loop over the possible column(s) of the top left corner of the mirror's square.
```
F²
```
Loop over the possible rotations of the mirror.
```
⊞υ⟦Σ⭆⊕ζ⭆⊕ζ⁼§§θ⁺ι⎇λμ⁻ζμ⁺κξ§§θ⁺ι⎇λξ⁻ζξ⁺κμ⎇λι⁺ιζκλ⟧
```
Calculate the number of tiles it reflects exactly. Exact matches are counted twice and the diagonal is also counted but this doesn't affect the relative score. Push this number along with the potential solution to the predefined empty list.
```
I✂⌈υ¹
```
Output the solution with the highest number of exactly reflected tiles.
[Answer]
# Python3, 557 bytes:
```
E=enumerate
V=lambda x,y,n,m:0<=x<n and 0<=y<m
U=lambda j,k,J,K,b,n,m:b[j][k]==b[J][K]if V(j,k,n,m)and V(J,K,n,m)else 0
def f(b):
n,m=len(b),len(b[0])
q,r=[i for x,u in E(b)for y,_ in E(u)for i in[(x,y,0,0,x,y)]*(x+1>=min(n,m)and y+min(n,m)<=m)+[(x,y,1,0,x,y)]*(x+1>=min(n,m)and y+1>=min(n,m))],[]
while q:
x,y,d,c,X,Y=q.pop(0)
if abs(X-x)+1==min(n,m):r+=[(*[[x,y],[X,Y]][d],d,c)];continue
q+=[(x,y,d,c+U(*[[X+1,Y+1,X-1,Y-1],[X+1,Y-1,X-1,Y+1]][d],b,n,m)+U(*[[X,Y+1,X-1,Y],[X,Y-1,X+1,Y]][d],b,n,m),X-1,Y+[1,-1][d])]
return max(r,key=lambda x:x[-1])
```
[Try it online!](https://tio.run/##fVRNb6MwED2vf8Wol5riVhgIH9mwt1660t5apfKiijREpQ0kIUSb/Prs2GbcrFStQsCeee/N@NmwPQ1vmy7Ktv35fF/U3aGt@2qo2VOxrtrFsoKjOIlOtNNgVhxnHVTdEnB4mrXskSDv4kM8iJ9iYYAL9V6qj7IoFuqhVD/LZgVPXEMw6Wn6E9dgPavX@xoCtqxXsOILb8oAo8W67nAizEMFpcdgJ/pCNbDa9NjOAZoO7hGhpyfxYqcHM21worhuOcAfPr3yhh99@aNom45TAyefZrOi9XxLkP8lXAS8UqiSwZ@3Zl3DDns2Fi3Fq5iL52J3t91seYBNAy68Wuz5/Pbo@bJw/GnvF4rfKIU0lEJSWaplqRW88vvrphua7lAjf6dxo7b/qBlzX4pn/M9v8XkrNds3IxvxpVUy@@CNlE@CLabBmnQJHelKChTFsIfr6@vh0HfQVkfei4/65M7D9KgQ5Z33sri6umIxSIgghBhCJu1TRzAemVEMMdO4fWjgESSYStkEMg1nCLHpyKRDgBSQAzLQgwwgB5gAJCYYUgoH0iAtzMXxQkrKEiKF5orMWJp7DiMDsZHh2TqZgaUGltlq2OwYS6y6GedUKaS2UqqWG7Y005TqpyylYrmRxnH@b082axebUCqkmqFlaRnbqiReTHqRuccwCkuyLad4Qm7FTFIHKcXcMjMyzHmdktEpqdo16A0ca9jOk4tFW39Tgtsi1uLU4CeUkgHLSSE0EbuzEfmQkay13Bls7Z@4TWXZheMRibn6ttPsopRlh85m48KEpVTAybg9cEbZFmPSSMjPxNnB3Ll1WIQkZFR@cVbdAXDbmdIuTlh2cZgkJSckE1sDAtIwEffqWP@0keb90t/YYfOy2FT9ku/xU/ttfMGVummrLW@6QTR3@@26GTh@4uhjCqtmPdQ9/7XpagH7EXD9u7tGEGPbHnl8xT@Vped5X4TDr8MRhs9/AQ)
] |
[Question]
[
[UTF-8](https://en.wikipedia.org/wiki/UTF-8) is a relatively simple way to encode Unicode codepoints in a variable-width format such that it doesn't easily confuse code that isn't Unicode aware.
## UTF-8 overview
* Bytes in the range of 1-0x7F, inclusive, are normally valid
* Bytes with the bit pattern `10XX XXXX` are considered continuation bytes, with the six least significant bits being used to encode part of a codepoint. These must not appear unless they are expected by a preceding byte.
* Bytes with the pattern `110X XXXX` expect one continuation byte afterward
* Bytes with the pattern `1110 XXXX` expect two continuation bytes afterward
* Bytes with the pattern `1111 0XXX` expect three continuation bytes afterward
* All other bytes are invalid and should not appear anywhere in a UTF-8 stream. 5, 6, and 7 byte clusters are possible in theory, but will not be allowed for the purposes of this challenge.
## Overlong encodings
UTF-8 also requires that a codepoint should be represented with the minimum number of bytes. Any byte sequence that could be represented with fewer bytes is not valid. Modified UTF-8 adds one exception to this for null characters (U+0000), which should be represented as `C0 80` (hex representation)), and instead disallows null bytes to appear anywhere in the stream. (This makes it compatible with null-terminated strings)
# Challenge
You are to make a program that, when given a string of bytes, will determine if that string represents valid Modified UTF-8 and will return a truthy value if valid and a falsy value otherwise. Note that you must check for overlong encodings and null bytes (since this is Modified UTF-8). You do not need to decode the UTF-8 values.
# Examples
```
41 42 43 ==> yes (all bytes are in the 0-0x7F range)
00 01 02 ==> no (there is a null byte in the stream)
80 7F 41 ==> no (there is a continuation byte without a starter byte)
D9 84 10 ==> yes (the correct number of continuation bytes follow a starter byte)
F0 81 82 41 ==> no (there are not enough continuation bytes after F0)
EF 8A A7 91 ==> no (too many continuation bytes)
E1 E1 01 ==> no (starter byte where a continuation byte is expected)
E0 80 87 ==> no (overlong encoding)
41 C0 80 ==> yes (null byte encoded with the only legal overlong encoding)
F8 42 43 ==> no (invalid byte 'F8')
```
# Rules
* Standard rules and loopholes apply
* Input and output can be in any convenient format as long as all values in the unsigned byte range (0-255) can be read in.
+ You may need to use an array or file rather than a null-terminated string. You need to be able to read null bytes.
* Shortest code wins!
* Note that using builtins to decode the UTF-8 is not guaranteed to conform to the requirements given here. You may need to work around it and create special cases.
EDIT: added bonus for not using builtins that decode UTF-8
EDIT2: removed bonus since only the Rust answer qualified and it's awkward to define.
[Answer]
# [Elixir](https://elixir-lang.org/), 69 bytes
```
import String
&valid? replace replace(&1,<<0>>,"\xFF"),"\xC0\x80","0"
```
[Try it online!](https://tio.run/##dY9RC4IwFIXf/RWyB1EYspngBFuINeiph159kdIYWMmy2L@3u0VENV@@y3bOPZfT9lJLNXXLcJLn4apGfz8qeTl5waPp5XHlq3bom0P7nmFAcVEQzjGqtRAoMrMitWYEYUTQFHnbXTzcx5vfxSE4dUoxIDFYcP4rY4qT/19IA38mzBJ1yOscFJYCKHHIwmwzc5clcxEbE85KQJkBcqfHRFg4VXvFInPItnf18sxVqD4R6dfT1pqe "Elixir – Try It Online")
Makes use of built-in string validation function. Takes input as Elixir binary.
[Answer]
# [APL (Dyalog Unicode)](https://www.dyalog.com/), ~~41~~ 39 [bytes](https://codegolf.meta.stackexchange.com/a/9429/43319 "When can APL characters be counted as 1 byte each?")[SBCS](https://github.com/abrudz/SBCS ".dyalog files using a single byte character set")
Anonymous tacit prefix function. Takes a Unicode string as argument where the characters' code points represent the input bytes.
```
{0::0⋄×⌊/'UTF-8'⎕UCS⍣2⎕UCS⍵}'À\x80'⎕R⎕A
```
[Try it online!](https://tio.run/##PY6xSgNBEIZ7n@LvNgGDs5fF26Q7LjlMJeSSziYgMUVAS0MIBCKHrl7QQrQURbBLIXmB5E3mRc451gsMw//Nv/PPjm6mjcvZaHp9VUw4e57z@rV3LoLAj3cQGsYp9Cm775pA51haVOf8l/PtYvejoPj@vcYPH@wydp/1Yk7tNsnq/o2f3IkaDpKGVT6G86@gUtuF2i8vbi2VXr8MLcZylfO1/4Bb7TZNzl6E0n4sfXDWS4sxJspomACmqY5KIgJpUODJEsIERnvqtGANNHlKCFbDBge7m8BGiEK0qoGGFFUk76VCT3I1LgeH5Njb5l/IlT8 "APL (Dyalog Unicode) – Try It Online")
`'À\x80'⎕R⎕A` **R**eplace `C0 80`s with the uppercase **A**lphabet
`{`…`}` apply the following anonymous function, where the argument is `⍵`:
`0::` if any error happens:
`0` return zero
`⋄` try:
`⎕UCS⍵` convert the string to code points
`'UTF-8'⎕UCS⍣2` interpret as UTF-8 bytes and convert resulting text back to bytes
`⌊/` lowest byte (zero if a null byte is present, positive if not, "infinity" if empty string)
`×` sign (zero if null byte is present, one if not)
[Answer]
# [Python 2](https://docs.python.org/2/), ~~104~~ 102 bytes
```
''.join(chr(int(c,16))for c in input().replace('00','-').replace('C0 80','0').split()).decode('utf-8')
```
[Try it online!](https://tio.run/##dZJBbsIwEEX3nGJEF04qQDaNSmjVRdXCthfoxphJSGU8keMUcno6hqIGQSMvovH8N9/frruwITc9vH28L16Gw@Eg@O4JX@Tz50GIyRdVLjEbn1QuJGakHtO0IA8GKserbkOSTjzWVhtMhJRiJMaiV3mTkMei5GJT24rb08kaDa15sw3FOBfpAfcG68Az1aD2PAfUGAfRCe7RQPR1Pz@ITEE2hexBQPzuoMMGEm0trLrAv9pj9BQ2CHIs97MleO1KTAfsCqQCOT0LHUHCbbGfZeDaX8ZZ3gSPesvCXAJjMvWP0JALlWt1qMidALuKo2wD7zVB@4D@WGbS@xzyDJS88B5nGfIeTWAT2xW3U3FNbaAga2l3TV1yuAry6cli318Mw1EAdNSWm1tMXUTQUjJmsYT8FV5nMO9hiGCrXXdDGhUKeMmLYPreYHdycSMiTg73NR8Z1xEUnwfksz6IvtFbciWb52dSuZL7@O5PL6mf39/FHTtxfcz/eIXkbAcWS23hGvcD "Python 2 – Try It Online")
Outputs via exit code
[Answer]
# Rust - ~~191 bytes~~ 313 bytes
Per comment below original did not work properly. New and improved version. No libraries are used, because The Mighty Rust Has No Need For You And Your Libraries. This code uses pattern matching with a state machine. By [shamelessly ripping off the UTF8 spec](http://www.unicode.org/versions/corrigendum1.html), after finding it via [reference and discussion by Jon Skeet](https://stackoverflow.com/questions/7113117/what-is-exactly-an-overlong-form-encoding), we can copy the spec almost character for character into a rust Match pattern match block. At the end, we add in Beefster's special Mutf8 requirement for C0 80 to be considered valid. Ungolfed:
```
/* http://www.unicode.org/versions/corrigendum1.html
Code Points 1st Byte 2nd Byte 3rd Byte 4th Byte
U+0000..U+007F 00..7F
U+0080..U+07FF C2..DF 80..BF
U+0800..U+0FFF E0 A0..BF 80..BF
U+1000..U+FFFF E1..EF 80..BF 80..BF
U+10000..U+3FFFF F0 90..BF 80..BF 80..BF
U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF
U+100000..U+10FFFF F4 80..8F 80..BF 80..BF
*/
let m=|v:&Vec<u8>|v.iter().fold(0, |s, b| match (s, b) {
(0, 0x01..=0x7F) => 0,
(0, 0xc2..=0xdf) => 1,
(0, 0xe0) => 2,
(0, 0xe1..=0xef) => 4,
(0, 0xf0) => 5,
(0, 0xf1..=0xf3) => 6,
(0, 0xf4) => 7,
(1, 0x80..=0xbf) => 0,
(2, 0xa0..=0xbf) => 1,
(4, 0x80..=0xbf) => 1,
(5, 0x90..=0xbf) => 4,
(6, 0x80..=0xbf) => 4,
(7, 0x80..=0x8f) => 4,
(0, 0xc0) => 8, // beefster mutf8 null
(8, 0x80) => 0, // beefster mutf8 null
_ => -1,
})==0;
```
[try it on the rust playground](https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=03a2127a05452312701fb98c44ebd8fd)
] |
[Question]
[
I work at a bakery that serves Wheat, Rye, Barley, Grain, and French bread, but the baker's a little weird - he stacks the loaves in random order, and sometimes just leaves some shelves at the end empty.
Each day, the same customer comes in and asks for one of each loaf of bread, but the tricky thing is, he's a germophobe, so when I fill his bag, I can't take loaves from two adjacent shelves in consecutive selections.
It takes one second to walk between adjacent shelves. It's a busy store; for any random configuration of loaves, I'd like to minimize the time it takes to get one of each unique loaf. I can start and end at any shelf.
If today's ordering is `W B W G F R W`, a possible path is `0, 3, 5, 1, 4`, for a total of 12 seconds: `abs(3-0) + abs(5-3) + abs(1-5) + abs(4-1) = 12`
(`1, 2, 3, 4, 5` doesn't work, because bread is picked consecutively from adjacent shelves.)
If it's `B W B G B F B R B W B F`, a possible path is `1, 3, 5, 7, 10`, for a total of 9 seconds.
The manager always makes sure there is a possible solution, so I don't need to worry about catching bad inputs. He usually sends me the order in a file, but if I want, I can type it to STDIN or read it a different way. I'd like the program to print out the indices of the best path, as well as its time, according to [default I/O rules](https://codegolf.meta.stackexchange.com/questions/2447).
In short:
1. 5 types of bread.
2. Loaf orders appears as strings of random order and length.
3. Must select one of each unique loaf.
4. Cannot make adjacent consecutive selections.
5. Minimize the distance between selection indices.
6. Don't need to worry about invalid inputs.
7. [Default I/O rules](https://codegolf.meta.stackexchange.com/questions/2447) apply.
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), shortest byte count wins.
[Answer]
# JavaScript (ES6), 114 bytes
*Saved 1 byte thanks to @Oliver*
Takes input as an array of characters. Outputs a comma-separated string where the first value is the total time and the next ones describe the path.
```
a=>(b=g=(r,s=o='',c,p)=>s[c>b|4]?o=(b=c)+r:a.map((v,i)=>s.match(v)||(d=p<i?i-p:p-i)<2||g([r,i],s+v,~~c+d,i))&&o)``
```
[Try it online!](https://tio.run/##XYyxDoIwEIZ3n8LJXkNhME7Eg6QD7i4OhIRSFGuQNpQwNbw6Uk0wYflyd///3UuMwspemSHsdH2fHzgLTKDCBqFnFjUSwiQzFBOby6RypyLVuOSSBn0sorcwACNTPl@WQT5hpM5BjeasUhWa2ISKno/ONZD3TBXMBiObJhnUi0QPB03Lcpa6s7q9R61u4AE5uRG2J9zjO108Mo/r71ZQuts6/zpfHb6KfLU3vcw/mz8 "JavaScript (Node.js) – Try It Online")
### Commented
```
a => ( // a[] = input array
b = // b = best score so far (initially a non-numeric value)
g = ( // g = recursive function taking:
r, // r = path
s = // s = string of collected loaves of bread
o = '', // o = final output
c, // c = current cost
p // p = index of the last visited shelf
) => //
s[c > b // if the final cost is not greater than our best score
| 4] ? // and we've successfully collected 5 loaves of bread:
o = (b = c) + r // update the current output and the best score
: // else:
a.map((v, i) => // for each loaf of bread v at shelf i in a[]:
s.match(v) || // if we've already collected this kind of bread
(d = // or the distance d
p < i ? i - p : p - i // defined as the absolute value of p - i
) < 2 || // is less than 2: stop recursion
g( // otherwise, do a recursive call to g() with:
[r, i], // r updated with the index of the current shelf
s + v, // s updated with the current loaf of bread
~~c + d, // c updated with the last distance
i // i as the index of the last shelf
) // end of recursive call
) // end of map()
&& o // return the current output
)`` // initial call to g() with r = [""]
```
[Answer]
# [Python 2](https://docs.python.org/2/), ~~212~~ 210 bytes
```
lambda s:min((sum(h(p)),p)for b in combinations(range(len(s)),5)for p in permutations(b)if(len(set(s[i]for i in p))==5)&all(d>1for d in h(p)))
h=lambda p:[abs(y-x)for x,y in zip(p,p[1:])]
from itertools import*
```
[Try it online!](https://tio.run/##RZCxboMwEIbn8BQ31eeKRkqlLEh0YKB7FwbKYIIdXGH7ZDtS6MtTm0Tqdvfdp7tfR2ucnX3fVP29LcKMk4BQGW0Rw83gjMR5SVw5DyNoCxdnRm1F1M4G9MJeJS7SYkjWebcoWyS9ucWnNXKtHpKMGHo9ZE3vGud1feYvYllw@jhlPmW@X@XFXD8DUdWLMeD6dt9P3Ms1W7@akErqT9XAh0J5Z0BH6aNzSwBtyPn4uk1SQZviVcUhQA3h6CUt4iKRASsZ48WBElbJSJXXNkIoKQ2OPy79IKeF/7j9aeBF0SLroIEOPqGFL@jSkoQyaBJqEmwSfvQt49sf "Python 2 – Try It Online")
2 bytes thx to [Jonathan Frech](https://codegolf.stackexchange.com/users/73111/jonathan-frech).
] |
[Question]
[
Dice Cricket is a game I was introduced to as a child and have used as a way to pass time for years since. I couldn't find a Wikipedia page so I'll explain the rules below.
# Dice Cricket Rules
## Premise
Dice Cricket is a game similar to scoring a game of [cricket](https://en.wikipedia.org/wiki/Cricket) as you watch it but rather than *watching* and recording the result, you are *rolling a die* and recording the result.
The results are recorded in a table as displayed at the bottom.
## Display
Dice Cricket uses a specific display to show all the information happening.
The table has 11 rows. Each row represents a batter. The layout of the row is explained below.
```
+------+------------------------------+---------+-----+
| Name | Runs | How Out |Score|
+------+------------------------------+---------+-----+
```
* Name: The name must be a string made up entirely of letters, upper or lower case
* Runs: A batter can face 30 balls. Each ball can be one of `1 2 4 6 . /`. This will be explained in more detail below
* How Out: The way the batter was out. Can be any of `Bowled, LBW (Leg Before Wicket), Caught, Retired or Not Out`
* Score: The sum of all numbers in `Runs`
## How the Game Works
In a game, there are always 2 batters out on the pitch. The first player is by default the current batter and the second in the "off" batter.
A game is made up of "balls": each ball in a cricket match is represented by a dice roll. Each roll does a different command:
* 1,2,4 and 6 make the batter score that much. If 1 is rolled, the current batter becomes the "off" batter and the "off" batter becomes the current
* 3 is a "dot ball", meaning that nothing happens. It is represented in the `Runs` section as a `.` and scores 0. A `0` may not be used to represent it.
* 5 is a wicket. If 5 is rolled, the current batter is "out", This means that a `/` is added to the runs and from then on, the batter cannot score anymore runs. The batter is then swapped with the next batter who has not batted. The `How Out` section is a random choice of the possible ways to get out: `Bowled, LBW, Caught`
Example for a wicket (this is just for clarity, this isn't how its outputted)
```
player a is on 4,6,2,6,4
player b is on 6,4,2,6,6
player c hasn't batted
player a is current batter
WICKET!!!
player a is on 4,6,2,6,4,/
player b in on 6,4,2,6,6
player c is on NOTHING
player c is current batter
```
Every 6 balls, the two batters switch; the current batter becomes the "off" batter and the "off" batter becomes the current batter
If the `Runs` section is filled (30 balls), the batter is out and the `How Out` section is set to `Retired`. A `/` **isn't** placed at the end of the `Runs` box.
# Actual Challenge (yes all that was rules of the game)
Your challenge is to output a completed table (like the example at the end), given a list of names. The contents of the output should contain only the table and/or leading or trailing whitespace.
## Rules
* [Standard loopholes](https://codegolf.meta.stackexchange.com/questions/1061/loopholes-that-are-forbidden-by-default) are disallowed
* All 11 players should have something in the `Runs` section.
* Only 1 player can be `Not Out`. Every other non-retired player should be out of a choice of `[Bowled, LBW, Caught]`
* The names can be any length between 1 and 6 that matches the regex `A-Za-z`
* The final line in the table should be the total line (see example)
* You don't have to align the text in the table in any way, but the row and column separators must be aligned.
## Example
```
Input:
['Fred', 'Sonya', 'David', 'Ben', 'Cody', 'Hazel', 'Nina', 'Kim', 'Cath', 'Lena', 'Will']
Output:
+------+------------------------------+---------+-----+
| Name | Runs | How Out |Total|
+------+------------------------------+---------+-----+
|Fred |.662/ | Caught | 14 |
+------+------------------------------+---------+-----+
|Sonya |1164/ | Caught | 12 |
+------+------------------------------+---------+-----+
|David |/ | LBW | 0 |
+------+------------------------------+---------+-----+
|Ben |424/ | LBW | 10 |
+------+------------------------------+---------+-----+
|Cody |62/ | Bowled | 8 |
+------+------------------------------+---------+-----+
|Hazel |/ | LBW | 0 |
+------+------------------------------+---------+-----+
|Nina |161.6226166..44261442/ | Caught | 64 |
+------+------------------------------+---------+-----+
|Kim |11/ | Caught | 2 |
+------+------------------------------+---------+-----+
|Cath |6.21/ | LBW | 9 |
+------+------------------------------+---------+-----+
|Lena |/ | Bowled | 0 |
+------+------------------------------+---------+-----+
|Will |2 | Not Out | 2 |
+------+------------------------------+---------+-----+
| Total Runs | 121 |
+-----------------------------------------------+-----+
```
[Answer]
# [Python 3](https://docs.python.org/3/), ~~650~~ ~~621~~ ~~582~~ ~~572~~ 588 bytes
```
from random import*
h=str
c=h.center
a='+'.join(map('-'.__mul__,[0,6,30,9,5,0]))+'\n'
b=lambda x,r=6:x.ljust(r,' ')
j=''.join
t=lambda a:sum(map(int,a[:-1].replace(*'.0')))
P=print
def s(i=30):
while i:x=choice('12.4/6');yield x;i=('/'!=x)*~-i
def f(n,T=0):
n=[*map(b,n)]
P(a+f'| Name | Runs{" "*25}| How Out |Total|')
for x in n[:-1]:S=j(s());T+=t(S);P(a,x,b(S,30),c(choice(['Bowled','LBW','Caught']),9),c(h(t(S)),5),sep='|',end='|\n')
S=j(s());P(a,n[-1],b(S,30),' Not Out ',c(h(t(S)),5),sep='|',end='|\n');P(a+f'|{15*" "}Total Runs{15*" "} |{c(h(T),5)}|\n+{47*"-"}+{5*"-"}+')
```
[Try it online!](https://tio.run/##hVBNj9owEL3nV7hcxk5MFpaFaoN8Yatqpa7oqiDtgSJkiNMYJXaUOCUsoX@d2oHutT74jebjvXlTHE2q1ehySUqdo5Kr2ILMC10a30tZZUpvx9JwJ5QRpccZBBDutVQ45wWGPoSbTV5nmw1dDeiEjgb0kY7pYE1IAD8VeFuW8Xwbc9TQkk2iJsz2dWVwSQEB8fYMrmye@dfHo6rOO3KpDOWrqD9ch6UoMr4T2IdwAIQQ75UVpa17sUhQhSUbDUjkoUMqM4Fk1LBdqqXth@F9@HA3ATI9SpHFqJlKhuEOPrGG@H/6sptPsKJL1hEotvKd9JYqsvbQK@ZBAi2a81ygFv2oVXXqoZ5/Pz636Fkf0PfaoHapDc9a6wYlukQNkgqpbu1owfa4woRMlwEzeEGmlpA2dIsX9lCE7vBtzRXM9CETMVB4mb3Z/4nXv1IDa0IfXVuK3TShY0IrUTBogQoVW7QXtrIfMo5erazyhwSguTbdmvA/nunN7Wk49q3Jc2fr6vmWQdfXnhzT0tGc7WRwevjs9/q9c3AaXxHIJbGevpbOEYKFVkfugi/8t@wyM6EcPOn46PCZv4vMBXOpusZvMu/q3KQOX8Q1/SazzN7k8hc "Python 3 – Try It Online")
Well, it's been over 24 hours and this took me about an hour to whip up, so I hope I'm not FGITW'ing anyone, and I haven't golfed in Python in a while, so this was fun (although this is the second time I've answered one of my own questions with a long Python answer)
Please feel free to post golf suggestions, Python isn't my best language for golfing.
-68 bytes thanks to [FlipTack](https://codegolf.stackexchange.com/users/60919/fliptack)!
-8 bytes thanks to [Mr. Xcoder](https://codegolf.stackexchange.com/users/59487/mr-xcoder)
+16 bytes due to a bug
[Answer]
# [Charcoal](https://github.com/somebody1234/Charcoal), ~~277~~ 255 bytes
```
≔E¹¹⟦⟦⟧⁰S⟧θ≔⮌θηW⊖Lη«≔⊟ηι≔‽12.4/6ζ⊞υζ⊞§ι⁰ζ≔⎇⁼ζ/⁺²‽³⁼³⁰L§ι⁰ζ¿ζ§≔ι¹ζ⊞ηι¿⊖Lη¿⁼¬﹪Lυ⁶¬εF⟦⊟η⊟η⟧⊞ηκ»”|⁴B\[⎇⁻℅↧T`⁵·5KMK⟲M≦»→´⁶_⭆∨R▷↥l⁹KG…≦”Fθ«◨⊟ι⁷◨Σ§ι⁰¦³²§⪪”(3⪪⪫⧴πZJL:∨XI±URD↗Σ9⟦FZ∕↖l⪪”⁷⊟ι◧IΣE⊟ιΣκ⁶⸿⸿»”|QºWPD⟧zNφ[v?Π'vG”◧IΣEυΣι²⁸J±¹±¹FE¹³⁻²⁷⊗ι«B⁵⁵ιB⁴⁹ι¿‹ι²⁷«B³⁹ιB⁸ι
```
[Try it online!](https://tio.run/##fVPBbhoxED2XrxjtBVvaNgUSSNVTIK2SFigCpBwIB5c1rBWvDbs2BCq@nXq86wiqKnuxZ@Z53syb2UXK8oVm8nS6KwqxUmTA1qTRiGE2m8fwOYZHtbZmYnKhVoTOaQwb@rVWYcd8y/OCk41zp869S4XkQO75IucZV4YnpM/VyqQkpRT@1D5U70Z67TwxCPcm@MZMJTojUaP56fqqHbnoAaMjW6TEnht35lEl/JUIV15AVTmmPFcs35NvG8tkQQ4xRFeYaSRtQZoxVBwt6nwVpuVarGq8SExpyC2WQA4USoozTKOKc1lw8JWlVUf44v8aUMBYRT3Uhgx0YqUOCOs420iMoQPClzoHMgt6leecvtG9OLpjbeSGY0g0ZBkHgLFVBbzzPegd/LIGYKoNk8/5cx65LJ5o44dUphuxZCxWqfHDEo68Q/0ILoMTm/2jWwyt5hkyBCdrKbBGbZB8zI3IedLVO8kT6DHrcrnS@t0ngAipyl4FveTs86UhPVaUvLipoTi0X8qhtc/eRKG9N5EutfASeMUQ9A6PLSlESdG8RY4fNltPNRnyFTOcNHBs4RoE9T9TK4aBULiBnRjutf3tei4zodpd/UpubqrNQeP6y9ka9XlRoLDNTon2iFZAeOu2Mo614@k0q393utZjqE@02jO83LOt8J4uV3j0dLLH84EduMTLUCgP/CkyH2cmxdPtpHc/CSnr89PHrfwL "Charcoal – Try It Online") Link is to verbose version of code. Explanation:
```
≔E¹¹⟦⟦⟧⁰S⟧θ
```
Read in the 11 names (input is flexible: JSON, space separated, or newline separated) and create an array `q` of 11 batters, represented by their balls (as an array), status (as an integer) and name.
```
≔⮌θη
```
Create a reversed copy of the batters `h`. This represents the batters that are not out. The last two elements are the off and current batters.
```
W⊖Lη«
```
Repeat while there are at least two batters available.
```
≔⊟ηι
```
Extract the current batter to `i`.
```
≔‽12.4/6ζ
```
Generate a random ball in `z`.
```
⊞υζ
```
Add it to the overall list of balls using the predefined empty list `u`.
```
⊞§ι⁰ζ
```
Add it to the current batter's balls.
```
≔⎇⁼ζ/⁺²‽³⁼³⁰L§ι⁰ζ
```
If the ball is a `/`, then generate a random status `2..4`, otherwise if this is the batter's 30th ball then set the status to `1` otherwise `0`.
```
¿ζ§≔ι¹ζ⊞ηι
```
If the batter is out then store the batter's status otherwise put the batter back in to bat.
```
¿⊖Lθ¿⁼¬﹪ΣEηLκ⁶¬ζ
```
If there are at least two batters left, and the batter was out xor 6 balls have been played, then...
```
F⟦⊟η⊟η⟧⊞ηκ»
```
...take the off and current batters and put them back in reverse order.
```
”|⁴B\[⎇⁻℅↧T`⁵·5KMK⟲M≦»→´⁶_⭆∨R▷↥l⁹KG…≦”
```
Print the header.
```
Fθ«
```
Loop over the batters.
```
◨⊟ι⁷
```
Print the batter's name.
```
◨Σ§ι⁰¦³²
```
Print the batter's balls.
```
§⪪”(3⪪⪫⧴πZJL:∨XI±URD↗Σ9⟦FZ∕↖l⪪”⁷⊟ι
```
Print the batter's status by indexing into the string `Not OutRetiredBowled Caught LBW` split into substrings of length 7.
```
◧IΣE⊟ιΣκ⁶
```
Print the batter's score.
```
⸿⸿»
```
Move to the start of the next line but one.
```
”|QºWPD⟧zNφ[v?Π'vG”◧IΣEυΣι²⁸
```
Print the total.
```
J±¹±¹FE¹³⁻²⁷⊗ι«B⁵⁵ιB⁴⁹ι¿‹ι²⁷«B³⁹ιB⁸ι
```
Draw boxes around everything.
] |
[Question]
[
I have a bunch of boards I need to stack in as small a space as possible. Unfortunately, the boards fall over if I stack them more than 10 high. I need a program to tell me how to stack the boards to take as little horizontal space as possible, without stacking boards more than ten high, or having boards hanging out over empty space.
## Your Task:
Write a program or function, that when given an array containing the lengths of boards, outputs as ASCII art the way to stack the boards to conserve as much horizontal space as possible, without stacking the boards more than 10 high or having any part of any board hanging out over empty space. Your ASCII art should show the configuration of the boards, with each one shown using a different character. There will be a maximum of 20 boards. For example, if the input was [2,2,4,2,2,4,4,4], a possible output is:
```
dhh
dgg
dff
dee
abc
abc
abc
abc
```
which is a stable configuration (although this would fall over in ~0.1 seconds in real life).
## Input:
An array containing up to 20 integers, showing the lengths of the boards.
## Output:
ASCII art showing the configurations of the boards, as outlined above.
## Test Cases:
Note that there may be other solutions for the test cases, and the characters shown for each board may be different.
```
[12,2,2,2,3,4,4,8,8] -> ffgghhiii
ddddeeeeeeee
bbbbbbbbcccc
aaaaaaaaaaaa
[4,4,4,4,4,4,4,4,4,4,4,4] -> llll
aaaa
cfghk
cfghk
cfghk
cfghk
debij
debij
debij
debij
[4,4,4,4,4,4,3,3,3,2,2,2,1] -> jjml
iiil
hhhk
gggk
ffff
eeee
dddd
cccc
bbbb
aaaa
```
## Scoring:
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), lowest score in bytes wins
[Answer]
# [Python 3](https://docs.python.org/3.6/), 513 512 511 509 499 497 485 465 459 458 444 bytes
Incredibly bad runtime, will finish at some point
```
e,j,c=enumerate,len,range
def f(n,p=[],o=97):
r,l,m=lambda x:min(b,f(n[:i]+n[i+1:],x,o+1),key=j),chr(o),j(p)
b=[p,l*(sum(n)*2+m)][n>[]]
for i,a in e(n):
for h,d in e(p):
if a<11-j(d):b=r([p[f]+l*a*(f==h)for f in c(m)])
if(j(d)<10)*all(j(x)==j(d)for x in p[h:h+a])*(a<=m-h):b=r([p[f]+l*(h<=f<h+a)for f in c(m)])
if a<11:b=r(p+[l*a])
b=r(p+[l]*a)
return["\n".join("".join(9-u<j(x)and x[9-u]or" "for x in b)for u in c(10)),b][o>97]
```
[Try it online!](https://tio.run/##bVDBjoMgFDzXryCeQF83a3vo1kh/hOWACouuAqGa2K93QdtNNtkTmXkzb4bnHpO25ryuEnpoqDTzKL2YJAzSgBfmSyatVEhhA44yDpZeL6RMDh4GGOkgxroVaCnHzuAagoqVHc8N6/Ki5LCAzQsC3/JBewKN9tgS6LEjyaGmzMGQ4fs8YkOyUz4SzsyNcZ4clPWoA4E6g2QYhrSN0tDulNuoQ6eQqIri2OOWlDX1mDmmeD5kIsOKUk2iSUVLg8N2sntwlFfFO8nEMASwEEojFcVLFDumS50LTjIsKjoe9d/lWFdUVUHwz/pno03vchaabPQL8kwE6OU0e8PST5O@9TbcLX2@1@NcxT7CtGhhAXHrU5T@Fqu3xHlPDB8gUHNmb9cLXxtxl3dEEWYFnDiw4gRn@Ajh0RGHmymKwuWc78yEIyIvoHZI1h8)
Edit: -2 -8 bytes thanks to [@Mr. Xcoder](https://codegolf.stackexchange.com/users/59487/mr-xcoder)
Edit: -8 bytes thanks to [@notjagan](https://codegolf.stackexchange.com/users/63641/notjagan)
## Explanation
```
e,j,c=enumerate,len,range
# These built-ins are used a lot
def f(n,p=[],o=97):
# n is the remaining blocks
# p is the current stack
# o is the ASCI code for the next letter to use
r,l,m=lambda x:min(b,f(n[:i]+n[i+1:],x,o+1),key=j),chr(o),j(p)
# r is the recursive call, that also selects the smallest stack found
# l is the letter to use next
# m is the length of the current stack
b=[p,l*(sum(n)*2+m)][n>[]]
# Sets the current best, if there are no remaining blocks, select the found stack, else we set it to be worse than the possible worst case
for i,a in e(n):
# Loop through all the remaining blocks
for h,d in e(p):
# Loop through all the columns in the current stack
if a<11-j(d):b=r([p[f]+l*a*(f==h)for f in c(m)])
# If we can place the current block vertically in the current column, try it
if(j(d)<10)*all(j(x)==j(d)for x in p[h:h+a])*(a<=m-h):b=r([p[f]+l*(h<=f<h+a)for f in c(m)])
# If we can place the current block horizontally starting in the current column, try it
if a<11:b=r(p+[l*a])
# If the current block is lower than 10, try place it vertically to the right of the current stack
b=r(p+[l]*a)
# Try to place the current horizontally to the right of the current stack
return["\n".join("".join(9-u<j(x)and x[9-u]or" "for x in b)for u in c(10)),b][o>97]
# Return the best choice if we aren't in the first call to the function, that is the next letter is a. Else return the found best option formatted as a string
```
# [Python 3](https://docs.python.org/3.6/), 587 bytes
Actually runnable on TIO for some of the test cases
```
e,j,c=enumerate,len,range
def f(n,p=[],o=97,b=[]):
if(not n):return p
if not b:b="a"*sum(n)*2
r,q,s,l,m=lambda x:q(f(n[:i]+n[i+1:],x,o+1,b)),lambda x:[b,x][j(b)>j(x)],b,chr(o),j(p)
if j(b)<=m:return b
for i,a in e(n):
for h,d in e(p):
if a<11-j(d):b=r([p[f]+l*a*(f==h)for f in c(m)])
if j(d)<10 and a<=m-h and all(map(lambda x:j(x)==j(d),p[h:h+a])):b=r([p[f]+l*(h<=f<h+a)for f in c(m)])
if s==b:
if a<11and m+1<j(b):b=r(p[:]+[l*a])
if m+a<j(b):b=r(p[:]+[l for r in c(a)])
return["\n".join("".join(map(lambda x:" "if u>=j(x)else x[u],b))for u in c(9,-1,-1)),b][o>97]
```
[Try it online!](https://tio.run/##bVHdbrQgEL3efQriFayzTXWbtGtkX4SPC1ixagQpamKffj9G203/MkbgzMw5Z8C/T83gTrebgQ6u3LjZmqAmA71xEJR7NfvK1KSmDjwXEgZ@fgYdd6zY79oIDxNxrAhmmoMjHjGCmC40T1RyGGdLHTvk@12ANxihB8t7ZXWlyFK80UggilamTrRpVkhYYEgz0IzBvUhoWKToqGaXji5MgoZrE@jAoKOerYKYLLn9dKH3u3oIpAVFWkdM1I9eV6iBaoP8CmGvKrPs2NGKRcOBCi9qmfYHdaA15w3DphpbrtQyyT56sLzMHolyVezn9ths276nVnl6t45@Ocdq8KIpmlRJ9l2HNiWvy5j4QykKjZzrr0ZRxaZZiQOvPF4UMhXR792bTdWvNEHysJGrlXy7KZH8c8lDN7SOJh/rN/8JSSLjfOE4iOlHQxYxS3weJJw3wjMcs/jFJ9NSDJfzs7xd1WhGwgkVOeTwBNs/hgSR5bDFaYVe4CWCT/Bn/Mic1ti6szgFmkCp1QdKiiKX8bp8aN1EEWGfh3o7stt/)
Both solutions could probably be golfed quite a bit.
[Answer]
# Python3, 1081 bytes
Rather long, but crunches every test case, including several additional ones, in ~0.184 seconds
```
E=enumerate
R=range
from itertools import*
G=lambda l:[[j for j,_ in b]for a,b in groupby(E(l),key=lambda x:x[1]=='')if a]
def C(l,L,H):
q=[([a],[i])for i,a in E(l)if a<=L]
while q:
A,I=q.pop(0)
if sum(A)<=L and(H==0 or sum(A)==L):yield(tuple(A),I)
for i,a in E(l[max(I)+1:],max(I)+1):
if sum(T:=A+[a])<=L:q+=[(T,I+[i])]
def P(b,l,Q,t):
for i,a in E(b):
if''in a:
F=0
B,Y=eval(str(b)),[]
for g in G(a):
if(O:=[*C(l,len(g),t)]):
F,d=1,{}
for J,K in O:d[J]=K
O=[*d.items()]
M=max(sum(A)for A,_ in O)
V,I=min([(o,p)for o,p in O if sum(o)==M],key=lambda x:len(x[0]));Y+=I
for v in V:
Q+=1
for _ in R(v):B[i][g.pop(0)]=chr(Q)
if F or t:return(B,[y for x,y in E(l)if x not in Y],Q)
def f(l):
I,Q=1 if max(l)<11 else max(l),96
while I:
q,S=[(B:=[[''for _ in R(I)]for _ in R(10)],[*l],96)],[B]
while q:
b,L,Q=q.pop(0)
if[]==L:return b
if(C:=P(b,L,Q,1))and C not in S:q+=[C];S+=[C]
if(C:=P([*map(list,zip(*b))],L,Q,0)):
B,L,Q=C;
if(B:=[*map(list,zip(*B))])not in S:q+=[(B,L,Q)];S+=[B]
I+=1
```
[Try it online!](https://tio.run/##dVPbbtpAEH3nK/aNXRhFOEQVdbIPGOXilIiSRJGi1aqyy0Kcri8Yk0KrfjudWZsUqlaLsGdnzpkzFxfb6iXP@oOi3O0upcnWqSmjyrTuZRllC9Oal3nKksqUVZ7bFUvSIi@rTuta2iiNZxGzvlKvbJ6X7BW@sCRjsSYjgpiMRZmvi3jLL7kV8M1s96iNv1GelrLdFsmcRZq1ZmbORtzCGG6E32JLqbiKNKhEC@JLICI@4iHAhRzrFvv@kljDlhjOhhDK5UmRF7wn0MSY1TrlQ4GBLMpm/EbKHkOe@lbKsfC3ibEzXq0La/AKQsIdp1JptOGh6Hq@hv0riXvnf/TlsIsyKY2/7KLmRwi7pFm7gj7zGCxMoSLUEXfseJJ5u41m5DivZI8eATxL8xZZvqpKDBOgNF0TekHYax7VGhDNJ75UHWqbNRlfCEykGye7gpn04Oev2iL4LXwigok/U7dafqodEySYneCA0xUXur67k1Rt3SoCDuvJTkTtfsJep0nGFc@hcAH4dAH7vuTY4Tt9PHBSuFE9LcT5c1eGf2S9EfSpUc2mXek1r@R0ie/5m/ADbKtaNCPW8utLyaeimcUVjbbyS1Oty4wHoLYOvIHtwdJsWJZXZD9rQCTNZ44eTBzCVHrEQ2VbceF5zNiVaUz4@GG/aiGpXMIDDjrAzqt2@0BjKPSB5aFIUB2rEU5vAfX2YGFZjKs@PdxZFKDwkxg3ZbC4vuMjX9IeYTR4QuAys9G@kge3dCN9/uAehwDVSaOC22RVwY@k4B3cJO04eqLZkMAJGJ3vd4kq@gsUIEgc5eIOJeqMrqYQB7YryiSr@JyrAbD618dBt96vT@EUzqD@x3Pk806hPn3nHMDgyH0G/zz/jem7UzN6GLX7DQ)
] |
[Question]
[
A superior highly composite number is an integer where the ratio of its count of divisors to some power of the number is as high as possible. Expressing this as a formula:
Let d(n) be the number of divisors of n, including the number itself. For a given integer n, if there exists a number e such that d(n)/n^e is greater than or equal to d(k)/k^e for every integer k, then n is a highly composite number.
For more, see [Superior highly composite number](https://en.wikipedia.org/wiki/Superior_highly_composite_number) at Wikipedia, or [A002201](https://oeis.org/A002201) at OEIS.
Here are the initial values:
```
2, 6, 12, 60, 120, 360, 2520, 5040, 55440, 720720, 1441440, 4324320, 21621600, 367567200, 6983776800, 13967553600, 321253732800, 2248776129600, 65214507758400, 195643523275200, 6064949221531200
```
Your challenge is to take an index n, and output the nth number in this sequence.
You may use 0 or 1 indexing, and you may make a program which is only correct up to the limits of your language's data type(s), as long as it can handle the first 10 values at a minimum.
This is code golf. [Standard loopholes](https://codegolf.meta.stackexchange.com/questions/1061/loopholes-that-are-forbidden-by-default) apply.
[Answer]
# Mathematica, 277 bytes
```
(A=AppendTo;p[f_]:=Module[{p=f[[1]],k=f[[2]]},N[Log[(k+2)/(k+1)]/Log[p]]];m=#;f={{2,1},{3,0}};o=1;l={2};x=Table[p[f[[i]]],{i,o+1}];For[n=2,n<=m,n++,i=Position[x,Max[x]][[1,1]];A[l,f[[i,1]]];f[[i,2]]++;If[i>o,o++;A[f,{Prime[i+1],0}];A[x,p[f[[-1]]]]];x[[i]]=p[f[[i]]]];Times@@l)&
```
input
>
> [21]
>
>
>
output
>
> 6064949221531200
>
>
>
input
>
> [50]
>
>
>
output
>
> 247899128073275948560051200231228551175691632580942972608000
>
>
>
] |
[Question]
[
# Backstory
You wake up dizzy in a chemistry laboratory, and you realize you have been kidnapped by a old mad chemist. Since he cannot see very well because of his age, he wants you to work for him and only then, you can escape the laboratory.
# Task
It is your task to return the [structural formulae](https://en.wikipedia.org/wiki/Structural_formula) of the molecules whose [chemical formula](https://en.wikipedia.org/wiki/Chemical_formula) will be given as input. Note that only the carbon (`C`), oxygen (`O`) and hydrogen (`H`) atoms will be used as input. Unlike in chemical formulas, a `0` is a valid quantifier and a `1` cannot be omitted (e.g. `C1H4O0` is valid input, but `CH4` isn't).
To prevent ambiguity, we assume double and triple bonds do not appear in the molecules. All carbon atoms need 4 single bonds, all oxygen atoms need 2, and hydrogen atoms need one. We also assume that `O-O` bonds do not exist as well. The molecule does not have to exist nor be stable.
The input will never contain more than `3` carbon atoms to ensure lightness in the output's display.
You only should display the molecules whose carbons atoms are arranged in a straight line without interruption. Ergo, no `C-O-C` bonds.
You must return **all** possible molecules not excluded by the previous rules. You do not need to handle invalid inputs.
The following example displays all the solutions you have to handle for that molecule.
A rotation by 180 degrees in the plane of the page of one of the molecule's formula is considered a redundancy and does not need to be displayed.
In the example below I'll show all of the possible formulae for a molecule, then point out the ones that do not need to be displayed.
# Example
Input: `C2H6O2`
First, here are all the possible formulae for this input (Thank you to @Jonathan Allan)
```
01 H
|
O H
| |
H - O - C - C - H
| |
H H
02 H
|
H O
| |
H - O - C - C - H
| |
H H
03 H H
| |
H - O - C - C - O - H
| |
H H
04 H H
| |
H - O - C - C - H
| |
H O
|
H
05 H H
| |
H - O - C - C - H
| |
O H
|
H
12 H H
| |
O O
| |
H - C - C - H
| |
H H
13 H
|
O H
| |
H - C - C - O - H
| |
H H
14 H
|
O H
| |
H - C - C - H
| |
H O
|
H
15 H
|
O H
| |
H - C - C - H
| |
O H
|
H
23 H
|
H O
| |
H - C - C - O - H
| |
H H
24 H
|
H O
| |
H - C - C - H
| |
H O
|
H
25 H
|
H O
| |
H - C - C - H
| |
O H
|
H
34 H H
| |
H - C - C - O - H
| |
H O
|
H
35 H H
| |
H - C - C - O - H
| |
O H
|
H
45 H H
| |
H - C - C - H
| |
O O
| |
H H
```
And here are the formulae that should be in the output if we take out the rotations of 180° in the plane of the page :
```
01 H
|
O H
| |
H - O - C - C - H
| |
H H
03 H H
| |
H - O - C - C - O - H
| |
H H
12 H H
| |
O O
| |
H - C - C - H
| |
H H
13 H
|
O H
| |
H - C - C - O - H
| |
H H
14 H
|
O H
| |
H - C - C - H
| |
H O
|
H
15 H
|
O H
| |
H - C - C - H
| |
O H
|
H
23 H
|
H O
| |
H - C - C - O - H
| |
H H
25 H
|
H O
| |
H - C - C - H
| |
O H
|
H
35 H H
| |
H - C - C - O - H
| |
O H
|
H
```
You do not need to output the labels of the formulae and you can output either of the rotations when two exist. For example you can output either 02 or 35.
Here are some valid inputs to test your code:
```
C3H8O2 C1H4O0 C2H6O2 C1H4O1 C2H6O2
```
The PC the chemist gave you to complete your task is quite old so you do not have a lot of memory on it to save your code, thus this is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'") and the shortest amount of byte wins!
[Answer]
# Ruby, 275
```
->s{(k=4<<2*c=s[1].to_i).times{|i|z=" "*8
t=(" H|O|"[i%2*2,4]+"C|"*c+"O|H "[i>>c&2^2,4]).chars.map{|j|z+j+z}
(c*2).times{|j|t[4+j&-2][j%2*10,7]=" H - O - H "[[i>>j/2-1&4,-7-(i>>c*2-j/2-1&4)][j%2],7]}
i*(k+1)>>c+1&k-1<i||("%b"%i).sum%16!=s[5].to_i||i%7>c*3||puts(t)}}
```
Combined formulas for left and right sidechains and eliminated variable `h`
# Ruby, 279
```
->s{(k=1<<h=2+2*c=s[1].to_i).times{|i|t=(" H|O|"[i%2*2,4]+"C|"*c+"O|H "[i>>c&2^2,4]).chars.map{|j|(z=" "*8)+j+z}
c.times{|j|t[4+j*2][0,7]=" H - O -"[i>>j-1&4,7]
t[4+j*2][10,7]="- O - H "[i>>h-j-3&4^4,7]}
i*(k+1)>>h/2&k-1<i||("%b"%i).sum%16!=s[5].to_i||i%7>c*3||puts(t)}}
```
**Ungolfed in test program**
```
f=->s{
(k=1<<h=2+2*c=s[1].to_i).times{|i| #c=number of C atoms. h=number of H (calculated)
#iterate i from 0 to (k=1<<h)-1
t=(" H|O|"[i%2*2,4]+"C|"*c+"O|H "[i>>c&2^2,4]). #compose a backbone string H-C...C-H. Insert O at the top where bit 0 of i set, and O at the bottom where bit c+1 of i set
chars.map{|j|(z=" "*8)+j+z} #convert string to an array of characters, pad each character left and right with 8 spaces
c.times{|j|t[4+j*2][0,7]=" H - O -"[i>>j-1&4,7] #overwrite spaces on left with H or HO according to bits 1 up to c
t[4+j*2][10,7]="- O - H "[i>>h-j-3&4^4,7]} #overwrite spaces on right with H or OH according to bits h-1 down to c+1
i*(k+1)>>h/2&k-1<i|| #rotate the bits of i by h/2. if this is less than i, do not output the structure (eliminates rotations by 180deg by outputtng the lexically highest)
("%b"%i).sum%16!=s[5].to_i|| #if the number of 1's in i differs from the number of O's indicated in the input, do not output
i%7>c*3|| #if i%7>c*3, do not output (empirical solution to avoid 90deg rotations for C=1)
puts(t) #if the above are all false, output the current structure.
}
}
f[gets]
```
**Output**
Spacing is as per question output. Backbone vertical instead of horizontal allowed per comments. Rotations of the entire display through 90 or 180 degrees considered equivalent.
```
C2H6O2
H
|
O
|
H - O - C - H
|
H - C - H
|
H
H
|
O
|
H - C - H
|
H - O - C - H
|
H
H
|
H - O - C - H
|
H - O - C - H
|
H
H
|
O
|
H - C - H
|
H - C - H
|
O
|
H
H
|
H - O - C - H
|
H - C - H
|
O
|
H
H
|
H - C - H
|
H - O - C - H
|
O
|
H
H
|
H - O - C - H
|
H - C - O - H
|
H
H
|
H - C - H
|
H - O - C - O - H
|
H
H
|
H - C - O - H
|
H - O - C - H
|
H
```
] |
[Question]
[
### Challenge:
Given a checkerboard, output the smallest amount of moves it would take (assuming black does not move at all) to king a red piece, if possible.
**Rules**:
Red's side will always be on the bottom, however their pieces may start in any row (even the king's row they need to get to). Black pieces are **stationary**, meaning they do not move in between red's movements, but they are removed from the board when captured. Note that pieces can start on *any* space on the board, including right next to each other. This is not how normal checkers is played, but your program must be able to solve these. (See input 5) However, checker pieces must only move **diagonally** (see input 3). Backward-capturing is allowed if the first capture is forward in the chain (see input 7).
**Input:**
An 8x8 checkerboard, with board spaces defined as the following characters(feel free to use alternatives as long as they're consistent):
. - Empty
R - Red piece(s)
B - Black piece(s)
**Output:**
The *smallest* number of moves it would take a red piece to be 'kinged' by entering the king's row on the top row of the board (black's side), 0 if no moves are required (a red piece started on king's row), or a negative number if it is impossible to king a red piece (ie black occupies it's entire first row).
Input 1:
```
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
R . . . . . . .
```
Output 1:
```
7
```
Input 2:
```
. . . . . . . .
. . . . . . . .
. . . . . B . .
. . . . . . . .
. . . B . . . .
. . . . . . . .
. B . . . . . .
R . . . . . . .
```
Output 2:
```
2
```
Input 3:
```
. B . B . B . B
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
R . . . . . . .
```
Output 3:
```
-1
```
Input 4:
```
. . . . . . . R
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
. . . . . . . .
R . . . . . . .
```
Output 4:
```
0
```
Input 5:
```
. . . . . . . .
. . . . . . . .
. . . . . . . .
. B . . B . . .
B . . . . B . .
. B . B . . . .
. . B . . B . .
. . . R R . . .
```
Output 5:
```
4
```
Input 6:
```
. . . . . . . .
. . . . . . . .
. B . . . . . .
. . B . . . . .
. B . B . . . .
. . . . R . . .
. . . B . . . .
. . . . R . . .
```
Output 6:
```
2
```
Input 7:
```
. . . . . . . .
. . . . . . . .
. . B . . . . .
. . . . . . . .
. . B . . . . .
. B . B . B . .
. . . . B . . .
. . . . . R . R
```
Output 7:
```
4
```
**Scoring:**
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so shortest code in bytes wins.
[Answer]
## JavaScript (ES6), ~~354~~ 322 bytes
Takes an array as input with:
* 0 = empty square
* 1 = red piece
* 2 = black piece
Returns the optimal number of moves, or 99 if there's no solution.
It's very fast but could be golfed much more.
```
F=(b,n=0,C=-1,i)=>b.map((v,f,X,T,x=f&7,y=f>>3)=>v-1||(y&&n<m?[-9,-7,7,9].map(d=>(N=c=X=-1,r=(d&7)<2,T=(t=f+d)>=0&t<64&&(x||r)&&(x<7||!r)?(!b[t]&d<0)?t:b[t]&1?N:b[t]&2&&(d<0&y>1|d>0&C==f)?(X=t,x>1||r)&&(x<6|!r)&&!b[t+=d]?c=t:N:N:N)+1&&(b[f]=b[X]=0,b[T]=1,F(b,n+!(C==f&c>N),c,1),b[f]=1,b[X]=2,b[T]=0)):m=n<m?n:m),m=i?m:99)|m
var test = [
[ 0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
1,0,0,0,0,0,0,0
],
[ 0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,2,0,0,
0,0,0,0,0,0,0,0,
0,0,0,2,0,0,0,0,
0,0,0,0,0,0,0,0,
0,2,0,0,0,0,0,0,
1,0,0,0,0,0,0,0
],
[ 0,2,0,2,0,2,0,2,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
1,0,0,0,0,0,0,0
],
[ 0,0,0,0,0,0,0,1,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
1,0,0,0,0,0,0,0
],
[ 0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,2,0,0,2,0,0,0,
2,0,0,0,0,2,0,0,
0,2,0,2,0,0,0,0,
0,0,2,0,0,2,0,0,
0,0,0,1,1,0,0,0
],
[ 0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,2,0,0,0,0,0,0,
0,0,2,0,0,0,0,0,
0,2,0,2,0,0,0,0,
0,0,0,0,1,0,0,0,
0,0,0,2,0,0,0,0,
0,0,0,0,1,0,0,0
],
[ 0,0,0,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,2,0,0,0,0,0,
0,0,0,0,0,0,0,0,
0,0,2,0,0,0,0,0,
0,2,0,2,0,2,0,0,
0,0,0,0,2,0,0,0,
0,0,0,0,0,1,0,1
]
];
test.forEach((b, n) => {
console.log("Test #" + (n + 1) + " : " + F(b));
});
```
] |
[Question]
[
*Inspired by [this question](https://math.stackexchange.com/q/1609248) over on Math.*
Let the prime factorization of a number, *n*, be represented as: \$P(n) = 2^a\times3^b\times5^c\times\cdots\$. Then the number of divisors of *n* can be represented as \$D(n) = (a+1)\times(b+1)\times(c+1)\times\cdots\$. Thus, we can easily say that the number of divisors of \$2n\$ is \$D(2n) = (a+2)\times(b+1)\times(c+1)\times\cdots\$,
the number of divisors of \$3n\$ is \$D(3n) = (a+1)\times(b+2)\times(c+1)\times\cdots\$,
and so on.
### Challenge
Write a program or function that uses these properties to calculate \$n\$, given certain divisor inputs.
### Input
A set of integers, let's call them \$w, x, y, z\$, with all of the following definitions:
* all inputs are greater than 1 -- \$w, x, y, z > 1\$
* \$x\$ and \$z\$ are distinct -- \$x\ne z\$
* \$x\$ and \$z\$ are prime -- \$P(x)=x, D(x)=2, P(z)=z \text{ and } D(z)=2\$
* \$w\$ is the number of divisors of \$xn\$ -- \$D(xn)=w\$
* \$y\$ is the number of divisors of \$zn\$ -- \$D(zn)=y\$
For the problem given in the linked question, an input example could be \$(28, 2, 30, 3)\$. This translates to \$D(2n)=28\$ and \$D(3n)=30\$, with \$n=864\$.
### Output
A single integer, \$n\$, that satisfies the above definitions and input restrictions. If multiple numbers fit the definitions, output the smallest. If no such integer is possible, output a [falsey](http://meta.codegolf.stackexchange.com/a/2194/42963) value.
### Examples:
```
(w, x, y, z) => output
(28, 2, 30, 3) => 864
(4, 2, 4, 5) => 3
(12, 5, 12, 23) => 12
(14, 3, 20, 7) => 0 (or some other falsey value)
(45, 13, 60, 11) => 1872
(45, 29, 60, 53) => 4176
```
### Rules:
* Standard code-golf rules and [loophole restrictions](http://meta.codegolf.stackexchange.com/q/1061/42963) apply.
* [Standard input/output rules](http://meta.codegolf.stackexchange.com/a/1326/42963) apply.
* Input numbers can be in any order - please specify in your answer which order you're using.
* Input numbers can be in any suitable format: space-separated, an array, separate function or command-line arguments, etc. - your choice.
* Similarly, if output to STDOUT, surrounding whitespace, trailing newline, etc. are all optional.
* *Input parsing and output formatting are not the interesting features of this challenge.*
* In the interests of sane complexity and integer overflows, the challenge number \$n\$ will have restrictions such that \$1 < n < 100000\$ -- i.e., you don't need to worry about possible answers outside this range.
### Related
* [Count the divisors of a number](https://codegolf.stackexchange.com/q/64944/42963)
* [Give the smallest number that has N divisors](https://codegolf.stackexchange.com/q/11080/42963)
* [Divisor sum from prime-power factorization](https://codegolf.stackexchange.com/q/53550/42963)
[Answer]
# [Jelly](http://github.com/DennisMitchell/jelly), ~~17~~ 16 [bytes](https://github.com/DennisMitchell/jelly/blob/master/docs/code-page.md)
```
×€ȷ5R¤ÆDL€€Z=Ḅi3
```
This is a brute force solution that tries all possible values up to 100,000. [Try it online!](http://jelly.tryitonline.net/#code=w5figqzItzVSwqTDhkRM4oKs4oKsWj3huIRpMw&input=&args=Miwz+MjgsMzA)
### Non-competing version
The latest version of Jelly has a bug fix that allows to golf down the above code to **15 bytes**.
```
ȷ5R×€³ÆDL€€=Ḅi3
```
[Try it online!](http://jelly.tryitonline.net/#code=yLc1UsOX4oKswrPDhkRM4oKs4oKsPeG4hGkz&input=&args=Miwz+MjgsMzA&debug=on)
### How it works
```
×€ȷ5R¤ÆDL€€Z=Ḅi3 Main link. Left input: x,z. Right input: w,y
¤ Combine the two atoms to the left into a niladic chain.
ȷ5 Yield 100,000 (1e5).
R Apply range. Yields [1, ..., 100,000].
x€ Multiply each r in the range by x and z.
This yields [[x, ..., 100,000x], [z, ..., 100,000z]].
ÆD Compute the divisors of each resulting integer.
L€€ Apply length to each list of divisors.
This counts the divisors of each integer in the 2D array.
Z Zip; group the divisors of kx and kz in pairs.
= Compare each [divisors(kx), divisors(kz)] with [w, y].
This yields a pair of Booleans.
Ḅ Convert each Boolean pair from binary to integer.
i3 Find the first index of 3. Yields 0 for not found.
```
] |
[Question]
[
## Challenge
Given two inputs, a positive ion and a negative ion, you must output the formula for the ionic compound which would be made from the two ions. This basically means balancing out the charges so they equal zero.
Do not bother with formatting the formula with subscript numbers, but you must have brackets for the multi-atom ions (such as `NO3`).
You do not have to account for any errors (for example, if someone inputs two negative ions, you can just let the program fail).
**Note:** Take Fe to have a charge of 3+
## Ions
All of the ions which need to be accounted for are found along with their charges on the second part of the [AQA GCSE Chemistry Data Sheet](http://filestore.aqa.org.uk/subjects/AQA-CHEMISTRY-DATA-SHEET.PDF).
### Positive ions
* H+
* Na+
* Ag+
* K+
* Li+
* NH4+
* Ba2+
* Ca2+
* Cu2+
* Mg2+
* Zn2+
* Pb2+
* Fe3+
* Al3+
### Negative ions
* Cl-
* Br-
* F-
* I-
* OH-
* NO3-
* O2-
* S2-
* SO42-
* CO32-
## Examples
Some examples:
**H** and **O** returns:- `H2O`
**Ca** and **CO3** returns:- `CaCO3`
**Al** and **SO4** returns:- `Al2(SO4)3`
Note the following case that you must account for:
**H** and **OH** returns:- `H2O` *not* `H(OH)`
[Answer]
# [Lua](https://www.lua.org/pil/contents.html), ~~174~~ 242 bytes
I forgot the brackets '-\_-, that got me up to 242. Oh well, it was a fun enough challenge at least.
```
i,c,a={Ba=2,Ca=2,Cu=2,Mg=2,Zn=2,Pb=2,Fe=3,Al=3,O=2,S=2,SO4=2,CO3=2},io.read(),io.read()
p,d=i[c]~=i[a],{SO4=1,NO3=1,OH=1,CO3=1}
k,m=p and i[c]or'',p and i[a]or''
a=k==m and a or (d[a]and'('..a..')'or a)
print(c..a=='HOH'and'H2O'or c..m..a..k)
```
[Try it online!](https://tio.run/nexus/lua#RY0/C8IwEMX3fIpsaeEItHW9QQXJohHclA5nUyTU/iHoVOpXr5eAONyPe@/e41YPDRDOO8IS9glvxvHBuA6M851xaLGC7ZNhWV3i2E3M2grLBfyoQ0suy/@bmMChvzX1h0k1zLFQwIkLBVjDiN1iER30OEkanIzpMSgFP0lJCsIOsU8eyTHIzPGFlcqU1qS1yhW7xC@DH15ZwyaiMtaoGDKljWd2@5Tu8nU1wpov "Lua – TIO Nexus")
Old version:
```
i,c,a={Ba=2,Ca=2,Cu=2,Mg=2,Zn=2,Pb=2,Fe=3,Al=3,O=2,S=2,SO4=2,CO3=2},io.read(),io.read()
p=i[c]~=i[a]
k,m=p and i[c]or'',p and i[a]or''
print(c..a=='HOH'and'H2O'or c..m..a..k)
```
Abusing Lua's tendency to initialize everything with a nil value we can cut down on storage costs. Still, Lua is still a bit clunky :(
[Answer]
# Java (~~619~~ ~~647~~ 667 bytes)
[Fixed] Update: H + OH returns HOH even though I hard coded it not to.... working on it
[Fixed] Update: Sometimes Parenthesis appear when they shouldn't
**Code**
```
String f(String[]a){if(Arrays.equals(a,new String[]{"H","OH"})|Arrays.equals(a,new String[]{"OH","H"}))return "H2O";List<String>b=Arrays.asList(new String[]{"H","Na","Ag","K","Li","NH4","Ba","Ca","Cu","Mg","Zn","Pb","Fe","Al","Cl","Br","F","I","OH","NO3","O","S","SO4","CO3"});Integer[]c={1,1,1,1,1,1,2,2,2,2,2,2,3,3,1,1,1,1,1,1,2,2,2,2},d={5,18,19,22,23};List<Integer>j=Arrays.asList(d);int e=b.indexOf(a[0]),f=b.indexOf(a[1]),g=c[e],h=c[f],i;if(f<e){String p=a[0];a[0]=a[1];a[1]=p;i=g;g=h;h=i;i=e;e=f;f=i;}boolean k=j.contains(e),l=j.contains(f),m=g==h,n=g==1,o=h==1;return (k&!m&!o?"("+a[0]+")":a[0])+(m?"":h==1?"":h)+(l&!m&!n?"("+a[1]+")":a[1])+(m?"":g==1?"":g);}
```
I wasn't sure how to do this without hard coding every ions charge, so it ended up being long. Lucky cause all the charges are 1, 2, or 3 so finding the amount of each ion is easy.
**Expanded**
```
import java.util.Arrays;
import java.util.List;
public class Compound {
public static void main(String[]a){
//System.out.println(f(a));
String[] pos = new String[]{"H","Na","Ag","K","Li","NH4","Ba","Ca","Cu","Mg","Zn","Pb","Fe","Al"};
String[] neg = new String[]{"Cl","Br","F","I","OH","NO3","O","S","SO4","CO3"};
for(int i = 0; i < pos.length; i++){
for(int j = 0; j < neg.length; j++){
System.out.println(pos[i] + " + " + neg[j] + " = " + f(new String[]{pos[i],neg[j]}));
System.out.println(neg[j] + " + " + pos[i] + " = " + f(new String[]{neg[j],pos[i]}));
}
}
}
static String f(String[]a){
if(Arrays.equals(a,new String[]{"H","OH"})|Arrays.equals(a,new String[]{"OH","H"}))
return "H2O";
List<String>b=Arrays.asList(new String[]{"H","Na","Ag","K","Li","NH4","Ba","Ca","Cu","Mg","Zn","Pb","Fe","Al","Cl","Br","F","I","OH","NO3","O","S","SO4","CO3"});
Integer[]c={1,1,1,1,1,1,2,2,2,2,2,2,3,3,1,1,1,1,1,1,2,2,2,2},d={5,18,19,22,23};
List<Integer>j=Arrays.asList(d);
int e=b.indexOf(a[0]),f=b.indexOf(a[1]),g=c[e],h=c[f],i;
if(f<e){String p=a[0];a[0]=a[1];a[1]=p;i=g;g=h;h=i;i=e;e=f;f=i;}
boolean k=j.contains(e),l=j.contains(f),m=g==h,n=g==1,o=h==1;
return (k&!m&!o?"("+a[0]+")":a[0])+(m?"":o?"":h)+(l&!m&!n?"("+a[1]+")":a[1])+(m?"":n?"":g);
}
}
```
[Try it here](http://ideone.com/RgXFkV)
**Data**
Let me know if any of them are wrong
```
H + Cl = HCl
Cl + H = HCl
H + Br = HBr
Br + H = HBr
H + F = HF
F + H = HF
H + I = HI
I + H = HI
H + OH = H2O
OH + H = H2O
H + NO3 = HNO3
NO3 + H = HNO3
H + O = H2O
O + H = H2O
H + S = H2S
S + H = H2S
H + SO4 = H2SO4
SO4 + H = H2SO4
H + CO3 = H2CO3
CO3 + H = H2CO3
Na + Cl = NaCl
Cl + Na = NaCl
Na + Br = NaBr
Br + Na = NaBr
Na + F = NaF
F + Na = NaF
Na + I = NaI
I + Na = NaI
Na + OH = NaOH
OH + Na = NaOH
Na + NO3 = NaNO3
NO3 + Na = NaNO3
Na + O = Na2O
O + Na = Na2O
Na + S = Na2S
S + Na = Na2S
Na + SO4 = Na2SO4
SO4 + Na = Na2SO4
Na + CO3 = Na2CO3
CO3 + Na = Na2CO3
Ag + Cl = AgCl
Cl + Ag = AgCl
Ag + Br = AgBr
Br + Ag = AgBr
Ag + F = AgF
F + Ag = AgF
Ag + I = AgI
I + Ag = AgI
Ag + OH = AgOH
OH + Ag = AgOH
Ag + NO3 = AgNO3
NO3 + Ag = AgNO3
Ag + O = Ag2O
O + Ag = Ag2O
Ag + S = Ag2S
S + Ag = Ag2S
Ag + SO4 = Ag2SO4
SO4 + Ag = Ag2SO4
Ag + CO3 = Ag2CO3
CO3 + Ag = Ag2CO3
K + Cl = KCl
Cl + K = KCl
K + Br = KBr
Br + K = KBr
K + F = KF
F + K = KF
K + I = KI
I + K = KI
K + OH = KOH
OH + K = KOH
K + NO3 = KNO3
NO3 + K = KNO3
K + O = K2O
O + K = K2O
K + S = K2S
S + K = K2S
K + SO4 = K2SO4
SO4 + K = K2SO4
K + CO3 = K2CO3
CO3 + K = K2CO3
Li + Cl = LiCl
Cl + Li = LiCl
Li + Br = LiBr
Br + Li = LiBr
Li + F = LiF
F + Li = LiF
Li + I = LiI
I + Li = LiI
Li + OH = LiOH
OH + Li = LiOH
Li + NO3 = LiNO3
NO3 + Li = LiNO3
Li + O = Li2O
O + Li = Li2O
Li + S = Li2S
S + Li = Li2S
Li + SO4 = Li2SO4
SO4 + Li = Li2SO4
Li + CO3 = Li2CO3
CO3 + Li = Li2CO3
NH4 + Cl = NH4Cl
Cl + NH4 = NH4Cl
NH4 + Br = NH4Br
Br + NH4 = NH4Br
NH4 + F = NH4F
F + NH4 = NH4F
NH4 + I = NH4I
I + NH4 = NH4I
NH4 + OH = NH4OH
OH + NH4 = NH4OH
NH4 + NO3 = NH4NO3
NO3 + NH4 = NH4NO3
NH4 + O = (NH4)2O
O + NH4 = (NH4)2O
NH4 + S = (NH4)2S
S + NH4 = (NH4)2S
NH4 + SO4 = (NH4)2SO4
SO4 + NH4 = (NH4)2SO4
NH4 + CO3 = (NH4)2CO3
CO3 + NH4 = (NH4)2CO3
Ba + Cl = BaCl2
Cl + Ba = BaCl2
Ba + Br = BaBr2
Br + Ba = BaBr2
Ba + F = BaF2
F + Ba = BaF2
Ba + I = BaI2
I + Ba = BaI2
Ba + OH = Ba(OH)2
OH + Ba = Ba(OH)2
Ba + NO3 = Ba(NO3)2
NO3 + Ba = Ba(NO3)2
Ba + O = BaO
O + Ba = BaO
Ba + S = BaS
S + Ba = BaS
Ba + SO4 = BaSO4
SO4 + Ba = BaSO4
Ba + CO3 = BaCO3
CO3 + Ba = BaCO3
Ca + Cl = CaCl2
Cl + Ca = CaCl2
Ca + Br = CaBr2
Br + Ca = CaBr2
Ca + F = CaF2
F + Ca = CaF2
Ca + I = CaI2
I + Ca = CaI2
Ca + OH = Ca(OH)2
OH + Ca = Ca(OH)2
Ca + NO3 = Ca(NO3)2
NO3 + Ca = Ca(NO3)2
Ca + O = CaO
O + Ca = CaO
Ca + S = CaS
S + Ca = CaS
Ca + SO4 = CaSO4
SO4 + Ca = CaSO4
Ca + CO3 = CaCO3
CO3 + Ca = CaCO3
Cu + Cl = CuCl2
Cl + Cu = CuCl2
Cu + Br = CuBr2
Br + Cu = CuBr2
Cu + F = CuF2
F + Cu = CuF2
Cu + I = CuI2
I + Cu = CuI2
Cu + OH = Cu(OH)2
OH + Cu = Cu(OH)2
Cu + NO3 = Cu(NO3)2
NO3 + Cu = Cu(NO3)2
Cu + O = CuO
O + Cu = CuO
Cu + S = CuS
S + Cu = CuS
Cu + SO4 = CuSO4
SO4 + Cu = CuSO4
Cu + CO3 = CuCO3
CO3 + Cu = CuCO3
Mg + Cl = MgCl2
Cl + Mg = MgCl2
Mg + Br = MgBr2
Br + Mg = MgBr2
Mg + F = MgF2
F + Mg = MgF2
Mg + I = MgI2
I + Mg = MgI2
Mg + OH = Mg(OH)2
OH + Mg = Mg(OH)2
Mg + NO3 = Mg(NO3)2
NO3 + Mg = Mg(NO3)2
Mg + O = MgO
O + Mg = MgO
Mg + S = MgS
S + Mg = MgS
Mg + SO4 = MgSO4
SO4 + Mg = MgSO4
Mg + CO3 = MgCO3
CO3 + Mg = MgCO3
Zn + Cl = ZnCl2
Cl + Zn = ZnCl2
Zn + Br = ZnBr2
Br + Zn = ZnBr2
Zn + F = ZnF2
F + Zn = ZnF2
Zn + I = ZnI2
I + Zn = ZnI2
Zn + OH = Zn(OH)2
OH + Zn = Zn(OH)2
Zn + NO3 = Zn(NO3)2
NO3 + Zn = Zn(NO3)2
Zn + O = ZnO
O + Zn = ZnO
Zn + S = ZnS
S + Zn = ZnS
Zn + SO4 = ZnSO4
SO4 + Zn = ZnSO4
Zn + CO3 = ZnCO3
CO3 + Zn = ZnCO3
Pb + Cl = PbCl2
Cl + Pb = PbCl2
Pb + Br = PbBr2
Br + Pb = PbBr2
Pb + F = PbF2
F + Pb = PbF2
Pb + I = PbI2
I + Pb = PbI2
Pb + OH = Pb(OH)2
OH + Pb = Pb(OH)2
Pb + NO3 = Pb(NO3)2
NO3 + Pb = Pb(NO3)2
Pb + O = PbO
O + Pb = PbO
Pb + S = PbS
S + Pb = PbS
Pb + SO4 = PbSO4
SO4 + Pb = PbSO4
Pb + CO3 = PbCO3
CO3 + Pb = PbCO3
Fe + Cl = FeCl3
Cl + Fe = FeCl3
Fe + Br = FeBr3
Br + Fe = FeBr3
Fe + F = FeF3
F + Fe = FeF3
Fe + I = FeI3
I + Fe = FeI3
Fe + OH = Fe(OH)3
OH + Fe = Fe(OH)3
Fe + NO3 = Fe(NO3)3
NO3 + Fe = Fe(NO3)3
Fe + O = Fe2O3
O + Fe = Fe2O3
Fe + S = Fe2S3
S + Fe = Fe2S3
Fe + SO4 = Fe2(SO4)3
SO4 + Fe = Fe2(SO4)3
Fe + CO3 = Fe2(CO3)3
CO3 + Fe = Fe2(CO3)3
Al + Cl = AlCl3
Cl + Al = AlCl3
Al + Br = AlBr3
Br + Al = AlBr3
Al + F = AlF3
F + Al = AlF3
Al + I = AlI3
I + Al = AlI3
Al + OH = Al(OH)3
OH + Al = Al(OH)3
Al + NO3 = Al(NO3)3
NO3 + Al = Al(NO3)3
Al + O = Al2O3
O + Al = Al2O3
Al + S = Al2S3
S + Al = Al2S3
Al + SO4 = Al2(SO4)3
SO4 + Al = Al2(SO4)3
Al + CO3 = Al2(CO3)3
CO3 + Al = Al2(CO3)3
```
**Note**
I started in Pyth, but then I got annoyed with the order and the parenthesis, [here](https://pyth.herokuapp.com/?code=%3DG%5B%22H%22+%22Na%22+%22Ag%22+%22K%22+%22Li%22+%22NH4%22+%22Ba%22+%22Ca%22+%22Cu%22+%22Mg%22+%22Zn%22+%22Pb%22+%22Fe%22+%22Al%22+%22Cl%22+%22Br%22+%22F%22+%22I%22+%22OH%22+%22NO3%22+%22O%22+%22S%22+%22SO4%22+%22CO3%22+1+1+1+1+1+1+2+2+2+2+2+2+3+3+1+1+1+1+1+1+2+2+2+2)J%40G%2B24xG%40QZK%40G%2B24xG%40Q1%40QZ%3FkqJKK%40Q1%3FkqJKJ&input=%22Al%22%2C%22SO4%22&debug=1) is what I had if anyone wants to finish it.
```
=G["H" "Na" "Ag" "K" "Li" "NH4" "Ba" "Ca" "Cu" "Mg" "Zn" "Pb" "Fe" "Al" "Cl" "Br" "F" "I" "OH" "NO3" "O" "S" "SO4" "CO3" 1 1 1 1 1 1 2 2 2 2 2 2 3 3 1 1 1 1 1 1 2 2 2 2)J@G+24xG@QZK@G+24xG@Q1@QZ?kqJKK@Q1?kqJKJ
```
[Answer]
# CJam, 176 bytes
```
"O S SO4 CO3 ""Cl Br F I OH NO3 """"H Na Ag K Li NH4 ""Ba Ca Cu Mg Zn Pb ""Fe Al "]_2{r\1$S+f#Wf=0#((z@}*_2$*_4=2*-_@/\@/@\]2/{~_({1$1>_el={'(@@')\}|0}&;}/]s"HOHH"1$#){;"H2O"}&
```
[Try it online](http://cjam.aditsu.net/#code=%22O%20S%20SO4%20CO3%20%22%22Cl%20Br%20F%20I%20OH%20NO3%20%22%22%22%22H%20Na%20Ag%20K%20Li%20NH4%20%22%22Ba%20Ca%20Cu%20Mg%20Zn%20Pb%20%22%22Fe%20Al%20%22%5D_2%7Br%5C1%24S%2Bf%23Wf%3D0%23((z%40%7D*_2%24*_4%3D2*-_%40%2F%5C%40%2F%40%5C%5D2%2F%7B~_(%7B1%241%3E_el%3D%7B'(%40%40')%5C%7D%7C0%7D%26%3B%7D%2F%5Ds%22HOHH%221%24%23)%7B%3B%22H2O%22%7D%26&input=Al%20SO4)
This was somewhat painful, particularly with all the special cases for parentheses, showing counts, the H2O, etc.
The data is not in a super compact format. It could be trimmed more, but the code needed to interpret it would probably compensate for the savings. So I went with an array of strings, where each string contains the atoms with the same charge, ordered from -2 to +3 (where the string for 0 is empty).
Explanation:
```
[..] Data, as explained above.
_ Duplicate data, will need it for both inputs.
2{ Loop over two inputs.
r Get input.
\ Swap data to top.
1$ Copy input to top (keep original for later).
S+ Add a space to avoid ambiguity when searching in data.
f# Search for name in all strings of data.
Wf= Convert search results to truth values by comparing them to -1.
0# Find the 0 entry, which gives the index of the matching string.
(( Subtract 2, to get charge in range [-2, 3] from index.
z Absolute value, we don't really care about sign of charge.
@ Swap second copy of data table to proper position for next input.
}* End loop over two inputs.
_2$* Multiply the two charges.
_4= We need the LCM. But for the values here, only product 4 is not the LCM.
2*- So change it to 2.
_@/ Divide LCM by first charge to get first count.
\@/ Divide LCM by second charge to get second count.
@\]2/ Make pairs of name/count for both ions...
{ ... and loop over the pairs.
~ Unpack the pair.
_( Check if count is > 1.
{ Handle count > 1.
1$ Get copy of name to top of stack.
1> Slice off first character to check if rest contains upper case.
_el Create lower case copy.
= If they are different, there are upper case letters.
{ Handle case where parentheses are needed.
'( Opening parentheses.
@@ Some stack shuffling to get values in place.
') Closing parentheses.
\ And one more swap to place count after parentheses.
}| End parentheses handling.
0 Push dummy value to match stack layout of other branch.
}& End count handling.
; Pop unused count off stack.
}/ End loop over name/count pairs.
]s Pack stack content into single string, for H2O handling.
"HOHH" String that contains both HOH and OHH, which need to be H2O.
1$#) Check if output is in that string.
{ If yes, replace with H2O.
; Drop old value.
"H2O" And make it H2O instead.
}& End of H2O handling.
```
[Answer]
## JavaScript (ES6), ~~316~~ 277 bytes
~~I've globalized the `p` and `n` variables (just like I did in CoffeeScript) for easier testing. Localizing the variables would not make a difference in character count.~~
```
f=(x,y)=>{i='indexOf',d='~NH4KNaAgLiBa~CaCuMgZnPbFeAlSO4CO3ClBrFIOHNO3',k=d[i](x),l=d[i](y),a=k<28?x:y,b=k<28?y:x,r=Math.ceil(k/11)-1,s=b=='F'?0:l<32;if(r==s)r=s=0;a=s&&a=='NH4'?'(NH4)':a;b=r&&/[A-Z]{2}/.test(b)?`(${b})`:b;return'H'==a&&b=='OH'?'H2O':a+(s?s+1:'')+b+(r?r+1:'')}
// Original attempt, 316 bytes
p={H:1,Na:1,Ag:1,K:1,Li:1,NH4:1,Ba:2,Ca:2,Cu:2,Mg:2,Zn:2,Pb:2,Fe:3,Al:3},n={Cl:1,Br:1,F:1,I:1,OH:1,NO3:1,O:2,S:2,SO4:2,CO3:2},f=(x,y)=>{a=p[x]?x:y,b=p[x]?y:x,z=p[a]==2&&n[b]==2,r=+z||n[b],s=+z||p[a];a=--r&&a=='NH4'?'(NH4)':a;b=--s&&/[A-Z]{2}/.test(b)?`(${b})`:b;return'H'==a&&b=='OH'?'H2O':a+(r?r+1:'')+b+(s?s+1:'')}
```
### ES5 variant, ~~323~~ 284 bytes
Not much changes apart from getting rid of the arrow function and template string:
```
f=function(x,y){i='indexOf',d='~NH4KNaAgLiBa~CaCuMgZnPbFeAlSO4CO3ClBrFIOHNO3',k=d[i](x),l=d[i](y),a=k<28?x:y,b=k<28?y:x,r=Math.ceil(k/11)-1,s=b=='F'?0:l<32;if(r==s)r=s=0;a=s&&a=='NH4'?'(NH4)':a;b=r&&/[A-Z]{2}/.test(b)?'('+b+')':b;return'H'==a&&b=='OH'?'H2O':a+(s?s+1:'')+b+(r?r+1:'')}
// Original attempt, 323 bytes
p={H:1,Na:1,Ag:1,K:1,Li:1,NH4:1,Ba:2,Ca:2,Cu:2,Mg:2,Zn:2,Pb:2,Fe:3,Al:3},n={Cl:1,Br:1,F:1,I:1,OH:1,NO3:1,O:2,S:2,SO4:2,CO3:2},f=function(x,y){a=p[x]?x:y,b=p[x]?y:x,z=p[a]==2&&n[b]==2,r=+z||n[b],s=+z||p[a];a=--r&&a=='NH4'?'(NH4)':a;b=--s&&/[A-Z]{2}/.test(b)?'('+b+')':b;return'H'==a&&b=='OH'?'H2O':a+(r?r+1:'')+b+(s?s+1:'')}
```
```
f=function(x,y){i='indexOf',d='~NH4KNaAgLiBa~CaCuMgZnPbFeAlSO4CO3ClBrFIOHNO3',k=d[i](x),l=d[i](y),a=k<28?x:y,b=k<28?y:x,r=Math.ceil(k/11)-1,s=b=='F'?0:l<32;if(r==s)r=s=0;a=s&&a=='NH4'?'(NH4)':a;b=r&&/[A-Z]{2}/.test(b)?'('+b+')':b;return'H'==a&&b =='OH'?'H2O':a+(s?s+1:'')+b+(r?r+1:'')}
;['H', 'Na', 'Ag', 'K', 'Li', 'NH4', 'Ba', 'Ca', 'Cu', 'Mg', 'Zn', 'Pb', 'Fe', 'Al'].forEach(function (q) {
['Cl', 'Br', 'F', 'I', 'OH', 'NO3', 'O', 'S', 'SO4', 'CO3'].forEach(function (w) {
document.body.innerHTML += '<p>' + q + ' + ' + w + ' = ' + f(q, w);
});
});
```
[Answer]
## CoffeeScript, ~~371~~ 333 bytes
This count includes newlines (some newlines can be replaced with semicolons but that wouldn't affect character count)
```
f=(x,y)->(i='indexOf';d='~NH4KNaAgLiBa~CaCuMgZnPbFeAlSO4CO3ClBrFIOHNO3';k=d[i] x;r=-1+Math.ceil k/11;l=d[i] y;a=if k<28then x else y
b=if k<28then y else x
s=if b=='F'then 0else 32>l
r=s=0if r==s;a='(NH4)'if'NH4'==a&&s;b='('+b+')'if/[A-Z]{2}/.test(b)&&r;if'H'==a&&b=='OH'then'H2O'else a+(if!s then''else 1+s)+b+(if!r then''else 1+r))
```
---
```
# Original attempt, 371 bytes
p={H:1,Na:1,Ag:1,K:1,Li:1,NH4:1,Ba:2,Ca:2,Cu:2,Mg:2,Zn:2,Pb:2,Fe:3,Al:3}
n={Cl:1,Br:1,F:1,I:1,OH:1,NO3:1,O:2,S:2,SO4:2,CO3:2}
f=(x,y)->(a=if p[x]then x else y
b=if p[x]then y else x
z=p[a]==n[b]==2;r=+z||n[b];s=+z||p[a];if--r&&a=='NH4'then a='(NH4)'
if--s&&/[A-Z]{2}/.test(b)then b='('+b+')'
if'H'==a&&b=='OH'then'H2O'else a+(if!r then''else r+1)+b+(if!s then''else s+1))
```
[Answer]
## CJam (137 bytes)
```
{{"SO4CO3ClBrFINO3OHNaAgKLiNH4BaCaCuMgZnPbFeAl":I\#~}$_s"HOH"="HO"1/@?_{I\#G-_0<B*-B/_W>+z}%_~1$=\1?f/W%[.{:T1>{_{'a<},,1>{'(\')}*T}*}]s}
```
This is an anonymous block (function) which takes two ions as strings wrapped in a list, and returns a string.
[Online demo](http://cjam.aditsu.net/#code=e%23%20Test%20cases%0A%22H%20OH%0A%20Ca%20CO3%0A%20CO3%20Ca%0A%20Al%20SO4%0A%20F%20Fe%22N%25%7BS%25_p%0A%0A%7B%7B%22SO4CO3ClBrFINO3OHNaAgKLiNH4BaCaCuMgZnPbFeAl%22%3AI%5C%23~%7D%24_s%22HOH%22%3D%22HO%221%2F%40%3F_%7BI%5C%23G-_0%3CB*-B%2F_W%3E%2Bz%7D%25_~1%24%3D%5C1%3Ff%2FW%25%5B.%7B%3AT1%3E%7B_%7B'a%3C%7D%2C%2C1%3E%7B'(%5C')%7D*T%7D*%7D%5Ds%7D%0A%0A~pNo%7D%2F).
### Dissection
```
{ e# Begin a block
{ e# Sort the input list
"SO4...Al" e# Ions in ascending order of charge
:I e# Stored as I for future reuse
\#~ e# Index and bit-invert to sort descending
}$
_s"HOH"="HO"1/@? e# Special case for water: replace ["H" "OH"] with ["H" "O"]
_{I\#G-_0<B*-B/_W>+z}% e# Copy the list and hash index in I to find the charges
_~1$=\1?f/ e# Replace [2 2] by [1 1]
W% e# Reverse the charges
[ e# Gather in an array
.{ e# Pairwise for each ion and its opponent's reduced charge...
:T1>{ e# If the charge (copied to T) is greater than 1
_{'a<},, e# Count the characters in the ion which are before 'a'
1>{'(\')}* e# If there's more than one, add some parentheses
T e# Append T
}*
}
]
s e# Flatten the list to a single string
}
```
[Answer]
# [Python 3](https://docs.python.org/3/), 364 bytes
Stores the ions by the absolute value of their charges as `index+1` in a 2-D array (0-index elements have +- 1 charge, etc.). Uses string.split() to save a few characters there. Handles the special case of `H + OH = H2O` first, then it calculates how many ions are needed of each sort as the LCM of their two charges divided by its charge. Then adds in parentheses if needed as well as the actual number of ions.
```
from math import*
o=["NH4 NO3 H Na Ag K Li OH I F Br Cl".split(),"CO3 SO4 Ba Ca Cu Mg Zn Pb S O".split(),["Fe","Al"]]
p=["H","OH"]
def c(i):
for h,k in enumerate(o):
if i in k:return-~h
def b(x,y):
if x in p and y in p:return"H20"
i,j=c(x),c(y);g=gcd(i,j);i//=g;j//=g;return((x,"(%s)"%x)[x[-1]in"34"]+str(j),x)[j==1]+((y,"(%s)"%y)[y[-1]in"34"]+str(i),y)[i==1]
```
[Try it online!](https://tio.run/##XZDBauMwFEXX1VdcNBSkVm2TODOLBC9SQ3GZaTzQXYUWjuM4ShPbyArYm/n1zFPSTmFACOnovPfEbQe/berodNq45oBD7rewh7Zx/oY1sebLdIplFiHFMseiwk/8sshSPOMJjw7Jnt937d56IRVPyHvNpnjMkdA64qXCW43fK7wi@/I0fyq54os9N4a1NCOlW5Zyw9blBoWwcsawaRy26h22RlkfD6XLfSma8AK7gQ38feZKf3T13Z/tuXIlejUEg4Q@CC3yeo3hfPxweToZcTLULi5EL1UhBjmv4qpYC2Jybh8e4mq@O@@XCkFdubjuJL/upe713djYmkdTbm4778ROKsK7OB6bWyGGT3WQevhftZK@p21QT77sfJF3ZYcYGt8Q/fjOrkRIAjzjUhFKJ1lASR4YRXuhSU7HwCk@4hT3hS/2E0EXGX21ST/7jJhhLAQapoY0/k2fsavW2dqLlQhMj4w6P@qxkfL0Fw "Python 3 – Try It Online")
] |
[Question]
[
# Programmer's Garden
Being a professional software developer, you cannot risk exposing yourself to the harsh non-artificial light of the sun, but you also have a soft spot for flowers, and want to keep your garden in good shape all year round.
To this end, a gardener is hired each month to tidy up the flowerbed at the foot of your house. However you need to make sure the gardener is doing his job properly, and work out a suitable payment for the hard working fellow. Naturally a software solution is best.
### Input
Your program will be fed input describing the flowerbed as it appears current, and details of items that need to be removed. The program must output the garden devoid of the clutter, and print out a breakdown of the gardeners pay. The input can be either be from STDIN, or as a single command line argument.
The first line of input is of the format
```
width height unwanted_item_type_count
```
where `width` is the width of the flowerbed, `height` is the height of the flowerbed (both in ASCII characters), and `unwanted_item_type_count` tells you how many lines will following containing a description of a type of item to be removed from the garden.
Each line for each unwanted type of item is of the format
```
width height string_representation name fee_per_item
```
where `width` is the width of the item, `height` is the height of the item (both in ASCII characters), `string_representation` is the string representation of the item without line breaks, `name` is an identifier for the type of item (spaces will be replaced with underscores), and `fee_per_item` is how much the gardener must be paid for the removal of each type of item.
For example
```
3 2 .R.\|/ rouge_flower 3
```
Represents an item type of name `rouge_flower`, which costs 3 to remove, and looks like this:
```
.R.
\|/
```
The items will not contain spaces, and no item may have a border consisting entirely of dots, and the string representation will also be the exact size described. Thusly, all of the following are invalid inputs:
```
3 1 ( ) space 0
1 1 . dot 0
2 1 .! bang 0
3 2 .@.\|/. plant 0
```
Note that 0 is however a valid fee (fees will always be integers greater than -1).
Note also that the flowerbed is predominately made up of dots (`.`) rather than spaces, and you can safely use whitespace as delimitation for all the inputs. The flowerbed is always bounded by dots itself.
After the unwanted item types are listed, then comes the ASCII representation of the flowerbed of given width and height.
### Output
Output should be to STDOUT, or suitable alternative if your language doesn't support it.
The output starts with a print-out of the flowerbed, but with all unwanted items removed (replaced with dots), so you can see how it should appear and check the gardener has done his job. Each item in the flowerbed will be surrounded by a rectangle of dots, and will be one-contiguous item (i.e. there will be no separating dots *inside* the item). For example
```
.....
.#.#.
.....
```
shows 2 separate items
```
.....
.\@/.
.....
```
shows 1 item
```
......
.#....
....|.
....|.
.o--/.
......
```
is invalid, as while the stone (#) can be matched, the snake (you couldn't tell it was a snake?) cannot because the stone interferes with the required surrounding of dots.
```
...
\@.
...
```
This is also invalid, as the snail is on the edge of the flowerbed, and the edge must always be bounded by dots in a valid input.
After this, there should be a listing of each type of unwanted item, giving the count, the cost per item, and costs for all the items (count \* cost per item), in the format:
```
<count> <name> at <cost_per_item> costs <cost>
```
After this, there should be a single line yielding the total cost (the sum of the costs for unwanted items):
```
total cost <total_cost>
```
### Example
For this given input
```
25 18 3
4 2 .\/.\\// weeds 5
2 1 \@ snails 2
1 1 # stones 1
.........................
.\@/.................\@..
............\/...........
......O....\\//..^|^.....
.#...\|/.........^|^.....
..................|......
.................\|/.....
..\@.....\/...........#..
........\\//....#........
....*....................
...\|/......\/......\@/..
...........\\//..........
..................*......
.......\@/.......\|/.....
...O.....................
..\|/.......*............
.......#...\|/....\@.....
.........................
```
The program should produce this output
```
.........................
.\@/.....................
.........................
......O..........^|^.....
.....\|/.........^|^.....
..................|......
.................\|/.....
.........................
.........................
....*....................
...\|/..............\@/..
.........................
..................*......
.......\@/.......\|/.....
...O.....................
..\|/.......*............
...........\|/...........
.........................
3 weeds at 5 costs 15
3 snails at 2 costs 6
4 stones at 1 costs 4
total cost 25
```
The output *must* be terminated by a line-break.
This is code-golf, may the shortest code win.
### Additional test case
*Edit: this used to contain Unicode, which isn't allowed in the flowerbed, far too modern. This has been rectified, sorry about that.*
```
25 15 5
5 3 ..@..\\|//.\|/. overgrown_plants 3
5 3 @-o....|...\|/. semi-articulated_plant 4
3 2 .|.\@/ mutant_plants 5
1 1 $ dollars 0
1 1 # stones 1
.........................
........@................
....$..\|/...........@...
............|.......\|/..
...#.......\@/...........
.........................
.........................
......@.......@......@...
.....\|/....\\|//...\|/..
.............\|/.........
.#....................#..
.........$.......|.......
...\/.......\/..\@/..\/..
..\\//.....\\//.....\\//.
.........................
```
Expected Output:
```
.........................
........@................
.......\|/...........@...
....................\|/..
.........................
.........................
.........................
......@..............@...
.....\|/............\|/..
.........................
.........................
.........................
...\/.......\/.......\/..
..\\//.....\\//.....\\//.
.........................
1 overgrown_plants at 3 costs 3
0 semi-articulated_plants at 4 costs 0
2 mutant_plants at 5 costs 10
2 dollars at 0 costs 0
3 stones at 1 costs 3
total cost 16
```
[Answer]
## Perl - 636
There is definitely some more golfing that can be done. And probably better ways to do it too.
```
<>;while(<>){if(/ /){chomp;push@v,$_}else{$t.=$_}}for(@v){r(split/ /)}say$t.$y."total cost $u";sub r{my($e,$w,$c,$h,$z)=@_;($i,$f,$q,$d)=(1,0,0,"."x$e);@m=($c=~/($d)/g);@l=split/\n/,$t;while($i>0){($g,$j)=(1,0);for(0..$#l){if($j==0&&$l[$_]=~/^(.*?)\.\Q$m[$j]\E\./){$j++;$l="."x length$1}elsif($j<@m&&$l[$_]=~/^$l\.\Q$m[$j]\E\./){$j++}elsif($j>0){$l[$_-1]=~s!.\Q$m[$j-1]\E.!" ".$m[$j-1]=~s/\./ /gr." "!e;($j,$g)=(0,0)}if($j==@m){$k=$j;for($f=$_;$f>$_-$j;$f--){$k--;$o="."x length$m[$k];$l[$f]=~s/^($l)\.\Q$m[$k]\E\./$1.$o./}($g,$j)=(0,0);$q++}}if($g){$i--}}$t=join("\n",@l)."\n";$t=~s/ /./g;$p=$z*$q;$u+=$p;$y.="$q $h at $z costs $p\n"}
```
635 characters + 1 for `-C` flag to handle the euros.
If you have the input stored in `input.txt` you can run it with:
```
cat input.txt | perl -C -E'<>;while(<>){if(/ /){chomp;push@v,$_}else{$t.=$_}}for(@v){r(split/ /)}say$t.$y."total cost $u";sub r{my($e,$w,$c,$h,$z)=@_;($i,$f,$q,$d)=(1,0,0,"."x$e);@m=($c=~/($d)/g);@l=split/\n/,$t;while($i>0){($g,$j)=(1,0);for(0..$#l){if($j==0&&$l[$_]=~/^(.*?)\.\Q$m[$j]\E\./){$j++;$l="."x length$1}elsif($j<@m&&$l[$_]=~/^$l\.\Q$m[$j]\E\./){$j++}elsif($j>0){$l[$_-1]=~s!\Q$m[$j-1]\E!$m[$j-1]=~s/\./ /gr!e;($j,$g)=(0,0)}if($j==@m){$k=$j;for($f=$_;$f>$_-$j;$f--){$k--;$o="."x length$m[$k];$l[$f]=~s/^($l)\.\Q$m[$k]\E\./$1.$o./}($g,$j)=(0,0);$q++}}if($g){$i--}}$t=join("\n",@l)."\n";$t=~s/ /./g;$p=$z*$q;$u+=$p;$y.="$q $h at $z costs $p\n"}'
```
Here is the deparsed version. I went through and added some comments to help explain things. Maybe I'll go make the variable names more readable sometime. There may be some edge cases this doesn't work with but it works with the examples at least.
```
BEGIN { # These are the features we get with -C and -E flags
$^H{'feature_unicode'} = q(1); # -C gives us unicode
$^H{'feature_say'} = q(1); # -E gives us say to save 1 character from print
$^H{'feature_state'} = q(1);
$^H{'feature_switch'} = q(1);
}
<ARGV>; # throw away the first line
while (defined($_ = <ARGV>)) { # read the rest line by line
if (/ /) { # if we found a space (the garden doesn't have spaces in it)
chomp $_; # remove the newline
push @v, $_; # add to our array
}
else { # else, we construct the garden
$t .= $_;
}
}
foreach $_ (@v) { # call the subroutine r by splitting our input lines into arguments
r(split(/ /, $_, 0)); # the arguments would be like r(3,2,".R.\|/","rouge_flower",3)
}
say $t . $y . "total cost $u"; # print the cost at the end
# this subroutine removes weeds from the garden and counts them
sub r {
BEGIN {
$^H{'feature_unicode'} = q(1);
$^H{'feature_say'} = q(1);
$^H{'feature_state'} = q(1);
$^H{'feature_switch'} = q(1);
}
my($e, $w, $c, $h, $z) = @_; # get our arguments
($i, $f, $q, $d) = (1, 0, 0, '.' x $e); # initialize some variables
@m = $c =~ /($d)/g; # split a string like this .R.\|/ into .R. and \|/
@l = split(?\n?, $t, 0); # split the garden into lines to process line by line
while ($i > 0) {
($g, $j) = (1, 0);
foreach $_ (0 .. $#l) { # go through the garden
if ($j == 0 and $l[$_] =~ /^(.*?)\.\Q$m[$j]\E\./) { # this matches the top part of the weed. \Q and \E make it so the weed isn't intepreted as a regex. Capture the number of dots in front of it so we know where it is
++$j;
$l = '.' x length($1); # this is how many dots we have
}
elsif ($j < @m and $l[$_] =~ /^$l\.\Q$m[$j]\E\./) { # capture the next line
++$j;
}
elsif ($j > 0) { # if we didn't match we have to reset
$l[$_ - 1] =~ s[.\Q$m[$j - 1]\E.][' ' . $m[$j - 1] =~ s/\./ /rg . ' ';]e; # this line replaces the dots next to the weed and in the weed with spaces
# to mark it since it didn't work but the top part matches
# that way when we repeat we go to the next weed
($j, $g) = (0, 0);
}
if ($j == @m) { # the whole weed has been matched
$k = $j;
for ($f = $_; $f > $_ - $j; --$f) { # remove the weed backwards line by line
--$k;
$o = '.' x length($m[$k]);
$l[$f] =~ s/^($l)\.\Q$m[$k]\E\./$1.$o./;
}
($g, $j) = (0, 0);
++$q;
}
}
if ($g) {
--$i; # all the weeds of this type are gone
}
}
$t = join("\n", @l) . "\n"; # join the garden lines back together
$t =~ s/ /./g; # changes spaces to dots
$p = $z * $q; # calculate cost
$u += $p; # add to sum
$y .= "$q $h at $z costs $p\n"; #get message
}
```
**Feel free to suggest improvements!**
[Answer]
# Python 3, 459 bytes
```
from re import*
E=input()
W,H,C=map(int,E[0].split())
B,T,O='\n'.join(E[~H:]),0,''
for L in E[1:~H]:
w,h,s,n,c=L.split();w,h,c=map(int,(w,h,c));r,t='.'*(w+2),0;a=[r]+['.%s.'%s[i:i+w]for i in range(0,w*h,w)]+[r]
for L in['(%s)'%'\\n'.join('.{%d})%s(.*'%(i,escape(b))for b in a)for i in range(W)]:t+=len(findall(L,B));B=sub(L,r.join('\\%d'%b for b in range(1,h+4)),B,MULTILINE)
O+='%d %s at %d costs %d\n'%(t,n,c,t*c);T+=t*c
print(B+O+'total cost',T)
```
Assumes the input will be given as a list of strings.
] |
[Question]
[
**Scenario**
I am using pattern matching lockscreen and I sadly forgot my pattern. I would like to know how much time I will need to unlock it. Here are the specifications of Google's lock screen, that we will use for this challenge.
* Every 5 wrong code, the user has to wait `30 seconds` before any further entry.
* A pattern must, at least, consist in `4 points` (see below)
* A point can be only used once, but you can go over it several times (see image right below):

Here, the center point is only used once, even if we go over it again for this particular pattern.
**Hypothesis & Facts**
We'll assume we're superheroes and that we can draw any pattern in `1 second`, we never need to eat or sleep. Yeah, we're superhumans.
I'm a very unlucky person. "Worst case scenario" is my daily life so the pattern I will attempt **last** will be the right one.
**What do we have to pwn?**
For those who don't know it, Android (and other phones now) offers the ability of unlocking the phone through drawing a pattern on a 9-point matrix. This matrix can be described as follow :
```
C(A) M(B) C(C)
M(D) X(E) M(F)
C(G) M(H) C(I)
```
* C standing for "corner point"
* M for "middle point"
* X for "center point"
* I have given identifiers to the points to make it easier
The permitted **direct** connections are as follows :
**Corner point :**

**Middle point :**

**Center point :**

However, as pointed out by steveverrill, "once the centre has been used (and therefore becomes unavailable) a direct connection between the bottom left and top right corner becomes unambiguous and therefore possible". Same goes for every "middle point", if e.g. the point B has already been counted, then a direct connection between A and C is possible. If e.g. F has already been counted, then a direct connection between C and I is possible. Etc...
**Rules**
* The point of this challenge is to return how much time (in human readable form, aka year/day/month/hour/whatever the time you find) I will need to unlock this damn phone.
* You can't hardcode the number of possible valid patterns (don't even Google it, you fool), calculate it (that's actually the fun part, isn't it ?)
* Shortest piece of code wins
* Good luck !
[Answer]
# [Rebmu](http://hostilefork.com/rebmu/): ~~197 175 168~~ 167 characters
Generates combinations as a series of numbers (ex. 12369 is top-left to top-right to bottom-right), checks if combination is valid, and increments a counter if it is. This might take a **while\*** to run. Returns the number of seconds needed to unlock the phone.
```
B[[2 13][4 17][6 39][8 79][5 19][5 28][5 37][5 46][a 0]]Fdz[Q1feCb[st[a]paStsC/1 Qa^Qa^e?NNfiAtsC/2 e?NNfiArvTSc/2]]rpJ987653088[StsADj1233iA^e?SuqSf[++K]]adKmp30dvK 5
```
Unmushed and commented:
```
; for each subarray c:
; the sequences c/2 and c/3 are invalid before the point c/1 is pressed
; a 0 - a is never in the sequence, therefore 0 is always invalid
b: [[2 13] [4 17] [6 39] [8 79] [5 19] [5 28] [5 37] [5 46] [a 0]]
; checks (most) conditions of validity
f: dz[
; set q to 1
q: 1
; foreach array in b as c
fe c b [
; set a to be portion of s before c/1
st [a] pa s ts c/1
; q = q and (a does not contain c/2) and (a does not contain reverse of c/2)
q: a^ q
a^ e? nn fi a ts c/2
e? nn fi a ts rv c/2
]
]
; repeat 98765308 times, with j = 1 to 98765308
; 987653088 = 987654321 (largest valid combination) - 1234 (smallest valid combination) + 1
rp j 987653088 [
; set s to j+1233 (smallest valid combination - 1) as a string
s: ts ad j 1233
; if f returns trues and s does not contain duplicates, increment k
i a^ e? s uq s
f
[++ k]
]
; print k (number of combinations) + 30 * (k/5) -> number of seconds needed
ad k mp 30 dv k 5
```
The program loops from 1 to (987654321-1233), checking 1233+loop counter (therefore checking 1234 to 987654321).
If the number `987653088` is replaced with, `9876-1233` or `8643`, then the program will find the time taken for all 4-point combinations.
Output for `9876-1233=8643` (4-point combinations):
```
>> rebmu %combinations.rebmu
== 11344
```
Output for `98765-1233=97532` (4 and 5-point combinations):
```
>> rebmu %combinations.rebmu
== 61426
```
Output for `987654-1233=986421` (4,5,6-point combinations):
```
>> rebmu %combinations.rebmu
== 243532
```
---
\*4/5-point took me about 8 seconds to run; 4-6 took about 77 seconds. It might take ~24 hours or longer depending on who runs this to calculate number of combinations for 4-9 point combinations.
] |
[Question]
[
Inspired by [this question](https://gamedev.stackexchange.com/questions/3488/saves-in-exe-file).
Create a program that prompts the user to store some data, and when the program is quitting, spit out the program itself, except the session data changed.
The user then open the newly generated program, and can recall the data from the previous program.
Commands
* `KEY VALUE`: sets session variable `KEY` to `VALUE`
* `*`: clear all data
* `! KEY`: delete `KEY`
* `? KEY`: query `KEY` (if not exist: print nothing and move on)
* otherwise, quit the program
Neither key or value cannot contain any spaces.
The newly generated program's filename must identify the version of the program, you can use dates or counters.
Example interaction:
```
name test store name = test
data is now { name: test }
0 1 data is now { name: test, 0: 1 }
? name output: test
! 0 delete 0
data is now { name: test }
hello good world data is now { name: test, hello: good }
the extra word "world" is ignored
egiwiwegiuwe the "otherwise" case: quit program
```
The user opens the newly generated program
```
? name output: test
name retest data is now { name: retest }
* clear
data is now { }
```
Sample implementation: <https://gist.github.com/1128876>
Rules
* You do not need to preserve comments or insignificant whitespaces in the quined program: just preserve the functionality and the data
* You cannot use any external storage.
* No cheating quines, like any other quine problems.
* Shortest code wins.
[Answer]
## Ruby 1.9, 159 156
This program generates files named "1", "2", "3" and so on.
```
b={}
I=1
eval T="loop{c,d=gets.split
c==?*?b={}:d ?c==?!?b.delete(d):c==???puts(b[d]):b[c]=d :break}
open(I.to_s,?w){|f|f<<'b=%p
I=%d
eval T=%p'%[b,I+1,T]}"
```
[Answer]
## D (419 chars)
```
enum c=q{string[string] m;import std.stdio;import std.array;void main(){foreach(string s;lines(stdin)){auto a=s.split;if(!a.length)goto e;switch(a[0]){case "*":m.clear;break;case "!":m.remove(a[1]);break;case "?":writeln(m.get(a[1],""));break;default:if(a.length<2){goto e;}m[a[0]]=a[1];}stdout.flush;}e:write("static this(){");foreach(i,v;m)writef("m[`%s`]=`%s`;",i,v);write("}enum c=q{",c,"};mixin(c);");}};mixin(c);
```
formatted:
```
enum c=q{
string[string] m;
import std.stdio;
import std.array;
void main(){
foreach(string s;lines(stdin)){
auto a=s.split;
if(!a.length)goto e;
switch(a[0]){
case "*":m.clear;break;
case "!":m.remove(a[1]);break;
case "?":writeln(m.get(a[1],""));break;
default:if(a.length<2){goto e;}m[a[0]]=a[1];
}
stdout.flush;
}
e:write("static this(){");
foreach(i,v;m)writef("m[`%s`]=`%s`;",i,v);
write("}enum c=q{",c,"};mixin(c);");
}
};mixin(c);
```
variant of my [D quine](https://codegolf.stackexchange.com/questions/69/golf-you-a-quine-for-great-good/2987#2987)
the `*` command relies on `m.clear;` to work correctly which it doesn't in dmd 2.52 (bug in the compiler)
the need for `stdout.flush;` depends whether auto flush is enabled (it isn't on my machine)
[Answer]
## JavaScript, 245
```
(function(o,N){while(a=prompt()){a=a.split(' ')
b=a[0]
c=a[1]
if(b=='*')o={}
else if(b=='?'){if(o[c]!=N)alert(o[c])}
else if(b=='!')delete o[a[1]]
else if(c!=N)o[b]=c
else break}alert('('+arguments.callee+')('+JSON.stringify(o)+')')}({}))
```
] |
[Question]
[
## Overview
Shue (Simplified Thue) is a language that was designed by AnttiP for [this challenge](https://codegolf.stackexchange.com/q/242897/107299). A Shue program consists of the possible outputs and a list of string replacements. For example, the following program prints "yes" if an unary string is even:
```
yes
no
11=2
12=1
22=2
1=no
2=yes
```
[Try it online!](https://tio.run/##lVWxbtswEN35FYQmsnbVytkECJ2SqUA6FF1staCps01AIgWSSmok/nb3SFmOrMRBqsW6u8fHu8dHud37ndE3R9W0xnpqYU7d3hELGS0wSqVpWlUDs@uEseXvonxerQr@ibNiHH1LOCEVbGinwUnRAlM8JxQfCx6J1kkSIyxi9DW@b4ylkipNVY8Mj9pEiNAVloqwbrVKXsonwtmpcJEfU8e4fk1WXOEq/p9KX2tLf4xrslooB/SXqDu4tdZYtkl@COvAUghhTrfGU7kTVkiPySd5oGIT3lAFfsl9Tbe@kWwEdvDmCHsPji1l2fNOu/1Qp7f337/c3t9Ne8QNOqvDD@nd0oaVZ6sgtlFaeGMddurAs9OyrobLTK10zKjUtbXyLMrOz66qg6si5qXvJto5Sxvh5Y7VfGy5Jt1a07Xshk8ECRs/F/SJnW09QDPO5/RV9oYvs7zk/PCOyqMpA/VbzIexWiP8vO@o1w7@guw8MDmnYwEHEI7bqyv7UTutHgBjzD@pfoPGVBj9tB3E8HGH9zwkR6JFxJ3AIc45DY9/RmQvhzKo74L6A@JydtQ6VmOj@WlA99HVoSzm6wCII15WB4SJdaG3wGrQzPFZxl8jh26WJjezgBO8DBdHvA2dDh5Ozi1zU87WM@Q4MeTl4erqidiTIxlzk2vXzJqtFc1wz7RBh7S1kNCA9o4KC7Q1zqk1niIaFj2CN6Cia9iJB2U6y8M3mkhT4Yb4PU6Oe7SSNiTLigXJFkVGFovwVmBuUWDxiCD08@esJETpNhz23qXOV0qnFkTFeAo68KEB8A8jWO5sSsyiL3XLSWuV9gzLaQU9mB8zfP4B "Python 3 – Try It Online")
The possible outputs here are listed as "yes" and "no". Then comes the list of replacements. Here, "11" is replaced with "2", "22" with "2", "12" with "1", "1" with "no", and "2" with "yes". All replacements are done non-deterministically. Once the program reaches a state where one of the replacements is the output, it terminates and prints the output.
## Exact definition of Shue
###### Copied from the original post
The source code is interpreted as a list of bytes. The only characters with special meaning are the newline, the equals sign and the backslash. `\n` corresponds to a literal newline, `\=` to a literal equals sign and `\\` to a literal backslash. Any other use of `\` is an error. Every line must contain 0 or 1 unescaped equals signs.
Or in other words, to be syntactically valid, the program has to match the following regex: `/([^\n=\\]|\\=|\\n|\\\\)*(=([^\n=\\]|\\=|\\n|\\\\)*)?(\n([^\n=\\]|\\=|\\n|\\\\)*(=([^\n=\\]|\\=|\\n|\\\\)*)?)*/`
Here is the mathematical definition of a Shue program:
A Shue program is a set of terminator strings \$T\_e\$, and a set of transformation rules \$T\_r\$, which are pairs of strings.
The execution of a Shue program on a input string \$i\$ is defined as follows. Let \$U\$ be the minimal set, so that \$i\in U\$ and \$\forall a,x,y,b: axb \in U \land (x,y) \in T\_r \rightarrow ayb \in U\$. Let \$S=U\cap T\_e\$.
If \$S=\{x\}\$, then the program will terminate, and \$x\$ will be printed to stdout.
If \$S=\emptyset\$ and \$|U|=\aleph\_0\$, then the program will enter an infinite loop.
In all other cases, the behavior is undefined (yes, Shue isn't memory safe).
However, since most esolangs cannot process byte arrays, you may take a string or a list of lines as input. See the linked original challenge for a better definition and more examples.
## Reference Implementation
Here is the Python reference implementation:
```
import re, sys
re1 = re.compile(rb"(([^=]|\\=)*)(=([^=]|\\=)*)?")
def unescape(i):
ret = b""
esc = 0
for c in i:
if esc and c == b"\\":
ret+= b"\\"
esc = 0
elif esc and c == b"=":
ret+= b"="
esc = 0
elif esc and c == b"n":
ret+= b"\n"
esc = 0
elif esc:
raise ValueError(f"Parser error: got character {c} after \\")
elif c == b"\\":
esc = 1
else:
ret+= bytes([c])
if esc:
raise ValueError(f"Parser error: got EOL/EOF after \\")
return ret
def parse(i):
terminators = set()
rules = set()
lines = i.split(b"\n")
for l in lines:
m = re1.match(l)
if m.group(3):
rules|= {(unescape(m.group(1)), unescape(m.group(3)[1:]))}
else:
terminators|= {unescape(m.group(1))}
return terminators, rules
def execute(c, i):
terms, rules = parse(c)
universe = {i}
mod = True
while mod:
mod = False
new_universe = set()
for s in universe:
if s in terms:return s
for s in universe:
for a,b in rules:
for o in range(len(s)+1):
if s[o:o+len(a)] == a:
new_universe|= {s[:o]+b+s[o+len(a):]}
mod = True
universe = new_universe
raise ValueError(f"Program error: no replacements are possible (undefined behaviour)")
code = input().encode()
inp = sys.stdin.read().encode()
res = execute(code, inp)
print(res.decode())
```
## Rules
* Standard loopholes are forbidden
* You may take input either as a byte list, a single string, or a list of lines.
* As this is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), shortest program in bytes wins.
[Answer]
# Python3, 264 bytes:
```
lambda x,y:next(M(x,p(y)))
def M(s,g):
if s in g[0]:yield s
for a,b in g[1]:
for i in range(len(s)):
if a==s[i:i+len(a)]:yield from M(s[:i]+b+s[i+len(a):],g)
def p(s):
d={}
for i in s.split('\n'):d[c]=d.get((c:='='in i),[])+[[i,i.split('=')][c]]
return d
```
[Try it online!](https://tio.run/##RY5BbsMgEEX3nAJlAyOjqLibCokj5ASEBQ7gIjkYAZFsVT27C2mjzmr05@n9SXv9XOP7R8qHl9djMffJGryxXUS3VXqhG0t0BwBknccXWtgMAuHgccEh4lm9abEHt1hcEPZrxoZNvweuG/eMQg@yibOji4u0QDfg7jBSFhVEGHpu4KXyeb33LiWCHqahIX@A0K3@@Ulqmmax8usb/ZeUc0lLqJRcIwFh1U1Le55dpfQmJJGkIQGY0jAoFVh40ZKAbqxGOLv6yBHbI@UQK/WU8DaEnU6n3RUUV8S5HBEfJUfj2DfZslG2Y0MAjh8)
[Answer]
# [JavaScript (Node.js)](https://nodejs.org), 198 bytes
```
c=>g=(a,...b)=>c.every(s=>([_,p,q,r]=s.match(/^((?:\\?.)*?)(=(.*))?$/).map(t=>t&&eval(`"${t.split`"`.join`\\"`}"`)),q?[...a].map((_,i)=>b.push(a.slice(0,i)+a.slice(i).replace(p,r))):a!=p))?g(...b):a
```
[Try it online!](https://tio.run/##NU7RbsIwDHzvX6xCYLNg1r4Nye2HUEZCFkpYaUKTIbFpv74ugOYXn@/kuzuqiwp6sD4uevduxj2PmquWQQki2iFXmszFDFcIXMF6K7w4i2HDgU4q6gMs3wDqVdPUhPMagYHmiPVkiUn3ELmK06m5qA5kPvmOFHxno8wlHZ3tZdPk8ieXiOJcr1Oc2ty/YCtsCt6R/wwHUBQ6qw28JPL5/7BIg/GdStCLARFX6ol9Sm7hXnulRu364DpDnWthDzK7mpD1LisKLrOi5CIryxvixJV8EyXFwZ4AHyVh1vQzRJgVRVrjr/PRJsdxEaLSH4tgvwy/PuYP "JavaScript (Node.js) – Try It Online")
Fixed and optimized tsh's (deleted) answer
] |
[Question]
[
Turn-based tactics games like Advance Wars, Wargroove, and Fire Emblem are made up of a square grid of varying terrain with units of differing movement classes requiring different costs for each terrain type. We'll be investigating a subset of that problem.
## Challenge
Your task is to determine if one location is reachable from another given a grid of terrain costs and a movement speed.
Units can only move orthogonally where the cost of moving onto a square is the value of the corresponding cell on the grid (moving off is free). For instance, moving from a cell valued 3 onto a cell valued 1 costs 1 movement, but going the other way requires 3. Some squares may be inaccessible.
### Example
```
1 [1] 1 1 1
1 2 2 3 1
2 3 3 3 4
1 3 <1> 3 4
```
Moving from `[1]` to `<1>` requires a minimum of 7 movement points by moving right one square and then down three. Thus, if given 6 or less as the movement speed, you should output a falsy answer.
## Example Test Cases
These will use top-left-origin zero-indexed (row, column) coordinates rather than bracketed cells for start and end to make parsing easier. Unreachable cells will be represented with `X`
Case 1a
```
1 1 2 1 X
1 2 2 1 1
2 1 1 2 1
X X X 1 2
Speed: 5
From (2, 3) to (0, 1)
Output: True
```
Case 1b
```
1 1 2 1 X
1 2 2 1 1
2 1 1 2 1
X X X 1 2
Speed: 4
From (2, 3) to (0, 1)
Output: False
```
Case 1c
```
1 1 2 1 X
1 2 2 1 1
2 1 1 2 1
X X X 1 2
Speed: 5
From (0, 1) to (2, 3)
Output: False
```
Case 2a
```
3 6 1 1 X 4 1 2 1 X
5 1 2 2 1 1 1 X 1 5
2 1 1 1 2 1 1 1 X 1
2 1 1 3 1 2 3 4 1 2
1 1 2 1 1 4 1 1 1 2
3 2 3 5 6 1 1 X 1 4
Speed: 7
From (3, 4) to (2, 1)
Output: True
```
Case 2b
```
3 6 1 1 X 4 1 2 1 X
5 1 2 2 1 1 1 X 1 5
2 1 1 1 2 1 1 1 X 1
2 1 1 3 1 2 3 4 1 2
1 1 2 1 1 4 1 1 1 2
3 2 3 5 6 1 1 X 1 4
Speed: 4
From (3, 4) to (2, 1)
Output: False
```
Case 2c
```
3 6 1 1 X 4 1 2 1 X
5 1 2 2 1 1 1 X 1 5
2 1 1 1 2 1 1 1 X 1
2 1 1 3 1 2 3 4 1 2
1 1 2 1 1 4 1 1 1 2
3 2 3 5 6 1 1 X 1 4
Speed: 7
From (1, 8) to (2, 7)
Output: True
```
Case 3a
```
2 1 1 2
2 3 3 1
Speed: 3
From (0, 0) to (1, 1)
Output: False
```
Case 3b
```
2 1 1 2
2 3 3 1
Speed: 3
From (1, 1) to (0, 0)
Output: True
```
## Rules, Assumptions, and Notes
* Standard loopholes are banned, I/O can be in any convenient format
* You may assume coordinates are all on the grid
* Movement speed will never be over 100
* Inaccessible cells may be represented with very large numbers (e.g. 420, 9001, 1 million) or with 0 or null, whichever is most convenient for you.
* All inputs will consist of positive integers (unless using null or 0 to represent unreachable cells)
[Answer]
# TSQL query, ~~205~~ 191 bytes
Input is a table variable @t
@x=start xpos, @y=start ypos
@i=end xpos , @j=end ypos
@ =speed
```
DECLARE @t table(x int,y int,v int)
INSERT @t
values
(0,0,1),(0,1,1),(0,2,2),(0,3,1),(0,4,null),
(1,0,1),(1,1,2),(1,2,2),(1,3,1),(1,4,1),
(2,0,2),(2,1,1),(2,2,1),(2,3,2),(2,4,1),
(3,0,null),(2,1,null),(2,2,null),(2,3,1),(2,4,2)
DECLARE @x INT=2,@y INT=3,@i INT=0,@j INT=1,@ INT=5;
WITH C as(SELECT @y f,@x r,@ s
UNION ALL
SELECT f+a,r+b,s-v FROM C
JOIN(values(1,0),(0,1),(-1,0),(0,-1))x(a,b)ON
s>0JOIN @t
ON f+a=x and r+b=y)SELECT
max(iif(S>=0and f=@j and r=@i,1,0))FROM c
```
**[Try it online](https://data.stackexchange.com/stackoverflow/query/1019423/terrain-reachability)** ungolfed version
[Answer]
# [Python 2](https://docs.python.org/2/), 220 bytes
```
def f(m,a,w,h,r,c,R,C):
T=[w*[999]for _ in' '*h];T[r][c]=0;P=[(r,c)];j,k=1,0
for u,v in P:exec"U,V=u+j,v+k;j,k=-k,j\nif h>U>-1<V<w:q=T[U][V];T[U][V]=min(T[u][v]+m[U][V],q);P+=[(U,V)]*(q>T[U][V])\n"*4
return a>=T[R][C]
```
[Try it online!](https://tio.run/##zZJNb@IwEIbP@FeMeokN0xUhoSzQcKnErRKqACEZa5UFI76ShiSE7q9nx4mB3Va99LKrWLJnPO8zH3HyK1@/xq3zealXsOIRhnjCNaa4wBd8Ej0G40Ce6rLb7arVawo/YBM74NTXqj@WqZILFTT7o0ByUgjV3@IucLHJwMQesaBoGPX0m17cTXAaHBtbLBq7Mux@h9t5vFnBejAZ3LuP08dT7xCM5UTJqYGXexBtYj6WRyUL1YgqHx5Ef9SglEQUqs4PAxss5vFd3WeQ6vyYxhAOiPai5JM6Pwf7MPq5DCHryShMuLWKHrUFVEIRBM7MAb3PNFWc80Jg/i1L9pucC1H2kptOMutz5rEjFDMjG/IMCyy7R24mhvot0YtcL2l2tQgCeOYky9NNQihWS3VGPjPoAvc65pFsKlGdxHXqrJakVAY1kiFceIwNueM4zAW4LWO1yuUZq9qr5Zs7rwwzFkmxg7yJLhXqYUvgOD1qcaO6RHFhxsxuToZmvWwG5qOzobSRt9ATlgVfxfgIxAECAZHAoIYh/YCvsKB9g1ygf8M8eCilM/Cv2DZcweWNC212sf7wWp9Xer1Kz24x/kVBOcx9@5rJraYOHSrKQ/Btce670f/L0vwPpf1nc3MRvtviOu8fm30MzKgpS6nxqofQFJX2Y0OfiWzwRWwTnX8D "Python 2 – Try It Online")
Takes an array `m` of integers, with `'X'` as a larger-than-100 value;, a speed `a`, `m` having width `w` and height `h`; and returns whteher we can start at the zero-indexed row/column cell `(r,c)` and get to the final cell `(R,C)`.
The algorithm is a modified flood-fill.
Slightly ungolfed code:
```
def f(m,a,w,h,r,c,R,C):
T = [w*[999]for _ in ' '*h] # make an array same size as m, with all
# values 999, whose values will represent
# the cost of getting to each cell.
T[r][c] = 0 # set the starting location to a cost of 0
P = [(r,c)] # initialize a set of cells whose neighbors'
# cost might need to be be updated
j,k = 1,0 # and also j,k which will take on values:
# (1,0), (0,1), (-1,0), (0,1), used to
# probe orthogonal neighbors
for u,v in P: # scan the cells in P
for _ in '1234': # look at each of 4 orthogonal positions
U,V = u+j,v+k # U and V get the indexes of a neighbor
# of the current cell.
j,k = -k,j # this 'rotates' the j,k pairing.
if h>U>-1<V<w: # if the coordinates are in bounds...
q = T[U][V] # save the current 'cost' of getting to cell (U,V)
# see if we can reduce that cost, which is calculated
# by taking the cost of the currently scanned cell
# + the value from m for the neighbor cell.
T[U][V] = min(T[u][v]+m[U][V] ,q)
# if we can reduce the cost, add the neighbor
# to P because **it's** neighbors might,
# in turn, need updating.
P += [(U,V)]*(q>T[U][V])
return a>=T[R][C] # return if speed is enough for the cost.
```
[Answer]
# JavaScript (ES7), ~~116~~ 113 bytes
Takes input as `(matrix)([endRow, endCol])(speed, startRow, startCol)`. Expects large values for unreachable squares. Returns \$0\$ or \$1\$.
```
m=>e=>o=g=(s,y,x)=>m.map((r,Y)=>r.map((v,X)=>r[s<v|(x-X)**2+(y-Y)**2-1||g(s-v,Y,X,r[X]=1/0),X]=v),o|=y+[,x]==e)|o
```
[Try it online!](https://tio.run/##fVLBjoIwFLzzFb3Z6kNtC@smu/WyZ@8YwoG4aHYD1lCXaMK/s9SiFkO5lLZvZpj3pr9plapd@XM6@0f5nTV70RRinYm1FAeBFVzhQsS6mBfpCeMStu2hNIcKIn2I1WdV44sfkemUzfDV3@qNT@v6gJVfwRYiKOMoEXSxJNB@KwKyFtdZDJdEiIzUstkggWIPoRghCqhbWLdreQlYRWYX2@VetK6eCFNsJW463XJHJF7y4Xk7eVQyz@a5PODJV6oyRCekd7vHG4JjzU4IDkFLc0LQYoHO5V/mhgY2dJ/magirEUZWs2ysZ42Fa8NvdoddJ8HYvMJ@8WVCtD@O0DFIOk51sHifyl@89hId@kMwZOLO4n3d0DUco@SKmQ3GzEx2K9DawWjM7BHzEzoS88rItqbeLVk7Zebo99mqGaurIz7YETU2@e2FLcdtaoTB0sdr1Dabfw "JavaScript (Node.js) – Try It Online")
### Commented
```
m => // m[] = matrix
e => // e[] = target coordinates
o = // o = success flag, initialized to a non-numeric value
g = ( // g = recursive depth-first search function taking:
s, // s = speed
y, x // y, x = starting coordinates
) => //
m.map((r, Y) => // for each row r[] at position Y in m[]:
r.map((v, X) => // for each value v at position X in r[]:
r[ // this statement ultimately updates r[X]:
s < v | // abort if s is less than v
(x - X) ** 2 + // or the quadrance between (x, y)
(y - Y) ** 2 - 1 // and (X, Y) is not equal to 1
|| g( // otherwise, do a recursive call to g:
s - v, // subtract v from s
Y, X, // pass (Y, X) as the new coordinates
r[X] = 1 / 0 // temporarily make this cell unreachable
), // end of recursive call
X // restore r[X] ...
] = v // ... to its original value
), // end of inner map()
o |= y + [, x] == e // set the flag o if (y + ',' + x) matches (e + '')
) | o // end of outer map(); return o
```
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), 59 bytes
```
+2¦µ_2ịæ.ؽœị$Ʋ+5ịƲ$4¦01Ñḣ3Ḋ⁼/Ɗ?ḣ2=/ẸƊoF<0ẸƊƊ?
çⱮØ.,U$;N$¤Ẹ
```
[Try it online!](https://tio.run/##zVI9S8NQFN37Kzpk66NN3kcr1tKtbjoJSigOmkVaIrYObtWlECd16aCTUgdFsKA0fizv0fyP5I/Em/tKElonXUp49953zr3nHh45cjqdszguUTmWb/s0/LxU47Iaye/ZDdRGMCkJyMHE4HJsWuoqnN6zcOpF51@VwGvCjTYq4cc08NzWhokFwAX1GL2@qFGZ7Bj1LUM@ABGH/pOIBre70eBO@o1mdPFsmabZy3Zt1oGW760Tt7tehK564mZ2HfqjwEuoYt9FmC3AvWPHOUSGJzJaZfu0f@B2HS2khhqEuqCGsHkvjm3b5kS0iU0Jg2gSq00EseCjSQRrWNIMyhFZIBSGl5X4/5RQQ@v92VMVbpAZ4SgFgjXCSBWnsI/nx0VOOV0lUmCB0FeGFcuE5pGnQwyPyG@10M8v7vjqubPIGrqrrdbbUUwm0Rbh6VgqkYww/HnmXcjr3uWu9g8 "Jelly – Try It Online")
Not terribly fast; tries all paths until the speed units are exhausted, even retracing its steps. However, this avoids the need to check whether spaces are visited. Input is provided as `[nrows, ncols],[start_row, start_col],[end_row, end_col],speed,flattened matrix column-major`
### Explanation
Helper link
```
+2¦ | add the right argument to the second item in the left argument (current location)
µ | start a new monadic chain with the modified left argument
4¦ | for the fourth item (speed)...
_ | subtract...
ịƲ$ | the item located at...
2ịæ.ؽœị$Ʋ | the dot product of the current position and (number of columns,
| right-padded with 1)
+5 | plus five
? | Now, if...
Ɗ | next three as a monad
ḣ2=/ẸƊ | either current row or current column are equal to nrows/ncolumns respectively
o | or
F<0ẸƊ | any value is negative
0 | return zero
? | else if...
ḣ3Ḋ⁼/Ɗ | the second and third items (current and end pos) are equal
1 | return 1
Ñ | else pass the current list back to the main link
```
Main link
```
ç | call the helper link with the current list...
Ɱ | and each of
Ø.,U$;N$¤ | [0,1],[1,0],[0,-1],[-1,0]
Ẹ | Check if any are true
```
[Answer]
# [Jelly](https://github.com/DennisMitchell/jelly), 38 bytes
```
ạƝṢ€Ḅ’¬Ạ
ŒṪ’ḟŒPŒ!€ẎW€j¥@€ÇƇḊ€‘œị⁸§Ṃ’<⁵
```
An extremely inefficient full program accepting the terrain (with unvisitables as 101) then the start and end co-ordinates then the speed.
**[Try it online!](https://tio.run/##y0rNyan8///hroXH5j7cuehR05qHO1oeNcw8tObhrgVcRyc93LkKyHu4Y/7RSQFHJymC5Hf1hQOprENLHYDU4fZj7Q93dAFZjxpmHJ38cHf3o8Ydh5Y/3NkE1GbzqHHr////o6MVFBQMdYCEEYgwjOXSgYkYGoAJJBGocGwsUBuQaRSroxAN1GYIFDAHAA "Jelly – Try It Online")** (not much point trying most of the test cases!)
### How?
Creates a list of all permutations of each of the power-set of "all terrain locations except the start & end", surrounds each of these with the start & end, filters to those which make only orthogonal moves of distance one, drops the start from each, indexes back into the terrain, sums each, takes the minimum, subtracts one and tests that this is less than the speed.
] |
[Question]
[
>
> Disclaimer: The story told within this question is entirely fictional, and invented solely for the purpose of providing an intro.
>
>
>
I have a friend who is an architect, and, after explaining the concept of code-golf and this site to him, he said that I should code something actually useful for a change. I asked him what he would consider useful, and, being an architect, he replied that he would enjoy having a floor planner that gave him all possible arrangements for rooms of certain sizes within a house of a certain size. I thought I would prove that code-golf wasn't useless after all, and give him this program in the smallest number of bytes possible.
## Your Task:
Write a program or function that, when given an array D containing the dimensions of the entire house, and a second array R containing the dimensions of the interior rooms, output as ASCII art, all possible configurations of the rooms inside the house.
All rooms and the exterior walls of the house should be formed as standard ASCII boxes, using the | symbol for vertical walls, the - symbol as horizontal walls, and the + symbol for corners. For example, a house with the dimensions [4,4] will look like:
```
+----+
| |
| |
| |
| |
+----+
```
As you can see, corners do not count as part of a set of dimensions. The number of - or | characters forming a side should equal the number given in the dimensions. Rooms may share walls, or share walls with the house. A room may not contain smaller rooms within itself.
For example, the configuration
```
+--+---+-+
| | | |
| | | |
+--+---+ |
| |
| |
+--------+
```
is valid for D=[5,8], and R=[[2,2],[2,3]].
## Input:
Two arrays, one of which contains two integers, the dimensions for the house, and the other of which contains a series of arrays containing the dimensions for rooms.
## Output:
Either an array of all possible houses as strings, or a string containing all possible houses, delimited in some consistent way. Note that rotations of the exact same configuration should only be counted once.
## Test Cases:
```
D R -> Output
[4,3] [[2,1],[4,1]] -> +-+-+ +-+-+ +-+-+ Note that though there is an option to switch which side the [2,1] room and the [4,1] room are on, doing so would merely be rotating the house by 180 degrees, and therefore these possibilities do not count.
| | | +-+ | | | |
+-+ | | | | | | |
| | | | | | +-+ |
| | | +-+ | | | |
+-+-+ +-+-+ +-+-+
[4,7] [[3,1],[4,2],[2,2] -> +----+--+ +----+--+ +----+--+ +----+--+ There are some more possiblities I didn't feel like adding, but it's the same four again, just with the [4,2] and the [2,2] room switched.
| | | | | | | | | | | |
| | | | | | | | | | | |
+---++--+ +--+-+-++ +-+--++-+ ++---+--+
| | | | | || | | | | || | |
+---+---+ +--+---++ +-+---+-+ ++---+--+
```
## Scoring:
This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), lowest score in bytes wins!
[Answer]
# [Python 2](https://docs.python.org/2/), ~~625~~ ~~607~~ ~~602~~ ~~563~~ 551 bytes
1. -5 bytes thanks to Mr.Xcoder.
2. -12 bytes when avoiding deep-copying.
3. -39 bytes with some list simplifications.
```
r,z=range,len
L,C=D;p,q,v,w=['+'],['|'],'*',' '
H=[p+['-']*C+p]
P=[[e[:]for e in H+[q+[w]*C+q]*L+H]]
def g(M,x,y,N):
m=[e[:]for e in M]
try:
for i in r(z(N)):
for j in r(z(N[0])):
if v==N[i][j]and w!=M[x+i][y+j]:return[]
m[x+i][y+j]=m[x+i][y+j]in[w,v,N[i][j]]and N[i][j]or'+'
except:return[]
return m
for l,c in R:
H=[p+['-']*c+p]
P=[g(U,x,y,[e[:]for e in H+[q+[v]*c+q]*l+H])for U in P for x in r(L+2)for y in r(C+2)]
F=[]
for m in P:
if[e[::-1]for e in m[::-1]]not in F:F+=[m]
for m in F:
print
for e in m:print''.join(e).replace(v,w)
```
[Try it online!](https://tio.run/##bVLBjoIwED3br@ieCraa1d0Tm540xIMaY@KpmYPB4kKgYMMKmP13dwpmcZO9kHnvzbzOvFC21Wdh5velVO/iDSjZS6XmYgYC8QzgbsVN2qM5a5FpQ9ZiIZcfpbiIq6ilYpxhI/vGLxszwSgjK6lKrtiEwXjBSyA79NMqgLiwVNPE0BVXF65qJ19gvOYrAHLSMT17G9GIVmz9gNBc/h3aAKGVbVGhjkscZ72bt/Vdd0@mv6R6BcePkphepdyqBFQKR3Oi9YvcqIYjbnkKgdXVlzUKyCgfWPlUJ0bVeOnDobN41IXF2wnVTaTLajCifUVz4jbKROR22uOKT7FELhaKuZy9Q3fxf/lcXR/mk2E@vtMOTtt1hzb9oWs@75S2hwuEQEKJWzg27/rx5SR2/sFkNjyR9xhMUTkYBiGXKn@aC3GutImpCB2Ggo5hbJoWifG0P7W6zI6R9vBX8O/3Hw "Python 2 – Try It Online")
**Some explanations**
It is a greedy approach:
1. Find all positions where the first room can be allocated
2. Find all possible positions where the next room can be allocated from the remaining free space of the house, and so on for the other rooms.
3. If the last room was successfully allocated the code output the configuration if it is not a 180°-rotation of a previous configuration.
] |
[Question]
[
One of the cool features introduced in the C++11 standard is the ability to declare a template parameter as being [variadic](https://en.wikipedia.org/wiki/Variadic_template); i.e. that parameter represents a sequence of an arbitrary number of arguments (including zero!).
For example, suppose the parameter pack `args` expands contains the sequence `A0, A1, A2`. To expand the pack, an expression is followed using the expansion operator `...`, and the expression is repeated for each argument with the parameter pack replaced by each element of the pack.
Some example expansions (assume `f` and `g` are not variadic packs):
```
args... -> A0, A1, A2
f(args)... -> f(A0), f(A1), f(A2)
args(f,g)... -> A0(f,g), A1(f,g), A2(f,g)
```
If the expansion operator is used on an expression which contains multiple un-expanded parameter packs, the packs are expanded in lock-step. Note that it is required that all parameter packs which participate in a single expansion operator must all have the same length.
For example, consider the packs `args0 -> A0, A1, A2` and `args1 -> B0, B1, B2`. Then the following expressions expand to:
```
f(args0, args1)... -> f(A0, B0), f(A1, B1), f(A2, B2)
g(args0..., args1)... -> g(A0, A1, A2, B0), g(A0, A1, A2, B1), g(A0, A1, A2, B2)
```
The goal of this challenge is given an expression and set of parameter packs, produce the expanded equivalent.
Note that there must be at least one un-expanded parameter pack as the argument to the expansion operator. All of the following are syntax errors (assume `args0 = A0, A1, A2`, `args1 = B0, B1`):
```
f(args0, args1)... // packs must have the same length
f(c)... // no un-expanded packs in expansion operator
f(args0...)... // no un-expanded packs in expansion operator
```
Your program needs not handle any expressions which result in a syntax error.
# Input
Your program/function should take as input a dictionary-like object which associates a parameter pack name with it's arguments, and an expression to be expanded (expression syntax explained later). For example, in Python-like syntax the dictionary of packs might look something like this:
```
{'args0': ['A0', 'A1', 'A2'],
'args1': [],
'args2': ['B0', 'A1', 'B2']}
```
Feel free to adapt the parameter pack input dictionary as desired. For example, it could be a list of strings where each string is a space-separated list and the first value is the pack name:
```
args0 A0 A1 A2
args1
args2 B0 A1 B2
```
Expressions to be expanded will contain only valid C++ identifiers (case-sensitive alpha-numerics and underscore), function call operators, parenthesis grouping, commas, and the expansion operator. Any identifiers in the expression which are not in the dictionary of parameter packs are not variadic. You may assume the given expression has a valid expansion.
It is your decision on what restrictions there are on how whitespace is used (for example, every token has a space between it and other tokens, or no whitespace at all).
The input may come from any source desired (stdin, function parameter, etc.)
# Output
The output of your program/function is a single string representing the expanded expression. You are allowed to remove/add any whitespace or parenthesis grouping so long as the expression is equivalent. For example, the expression `f(a,b,c,d)` is equivalent to all of the following:
```
(f(((a,b,c,d))))
f ( a, b, c , d )
f((a), (b), (c), (d))
```
The output can be to any source desired(stdout, function return value, etc.)
# Examples
All examples are formatted as such:
The dictionary of packs are expressed as lines of strings in the example format given above (space separated, first value is the pack name), followed by the expression, and the expected result.
case 1:
```
args0 A0
args2 B0 A0
args1
args0...
A0
```
case 2:
```
args0 A0
args2 B0 A0
args1
args1...
// nothing
```
case 3:
```
args0 A0
args2 B0 A0
args1
f(args1)...
// nothing
```
case 4:
```
args0 A0
args2 B0 A0
args1
f(args1...)
f()
```
case 5:
```
args0 A0
args2 B0 A0
args1
f(C0, args0..., args2)...
f(C0, A0, B0), f(C0, A0, A0)
```
case 6:
```
args0 A0 A1
args1 B0 B1
args2 C0 C1
f(args0, args1, args2)...
f(A0, B0, C0), f(A1, B1, C1)
```
case 7:
```
args0 A0 A1
args0(C0)...
A0(C0), A1(C0)
```
case 8:
```
args0 A0 A1
args1 B0 B1
args0(args1(f))...
A0(B0(f)), A1(B1(f))
```
case 9:
```
args0 A0 A1
args1 B0 B1
f_(c)
f_(c)
```
case 10:
```
args0
args1 A0 A1
f(args0..., args1)...
f(A0), f(A1)
```
# Scoring
This is code-golf; shortest code in bytes wins. Standard loop-holes apply. You may use any built-ins desired.
[Answer]
# [Python 3](https://docs.python.org/3/), 567 bytes
```
lambda v,q:w(g(v,p(q),-1))
def c(s):
a=[];b=0;l=""
for x in s:
if x!=","or b:l+=x;b+=~-")(".find(x)%3-1
else:a+=[p(l)];l=""
return a+[p(l)]
p=lambda s:(0,p(s[:-3]))if"..."==s[-3:]else(1,(2,s.split("(")[0]),c(s[s.find("(")+1:-1]))if")"==s[-1]else(2,s)
def g(v,q,i):
if q[0]>1:return q[1]if q[1]not in v or i<0else v[q[1]][i]
if q[0]:return(g(v,q[1],i),[g(v,k,i)for k in q[2]])
a=[];i=0
while 1:
try:a+=[g(v,q[1],i)];i+=1
except:return a
w=lambda k:",".join(q for q in[w(x)for x in k]if q)if type(k)==list else k if type(k)==str else k[0]+"("+w(k[1])+")"
```
[Try it online!](https://tio.run/##TVLLjtwgEDwPX0GQIoGMLTNz84RIST6DcPCs8S4x68GGzENR8uuTbtu72ltTTRdV1cR7fjmPh0evfz5C@3rqWnqRU3Plz/wiI5@ELJUQpHM9feJJNGTXamOPJ10fg2aM7PrzTG/UjzRBb@d7evukmWSAnppQ6NvxVOh/JROcVb0fO34Tnw@lgqsuJNe0hTaRB2E3ttnl3/NI22JFSdSbqNTwGvQk05QHK4TvWVVVTOtkykNjkYsryfcyVSkGnznjTJjaCgmqTVqfRqxQTalWArGOq3UaRlebaHySHq2CmwlIvqpm0zUZZRdQ2fGc0fWFglP/pUYOejHYscbb99ltcokTm0AsDR4GqDC7AVkms7dWbNl6XZPd9cUHRxVmmuf7ktMHCrhU6CXE25OL@U1eS65veQ0NLKH6dfYjnyi@M8E75grxvy9sWKxAEjTfo@OD0Dr4lOliBWR9wFOeNxgsFZBjceUDSBEFpPjwr/E8Z5ruiZCWaiyqlDs/VrNrOy7gMPvIBSEBuu26oeBHlxDrAPvzlxDUhSBKCwa3BOYHaCK4bRUi6gxqsICDgMYS4vAKrhFei6F9cpxRJiljwB1nP2be805SJ8SjnZ9TTb/VlGC1p9/xsNSK9PxHLelyA37WWu0FlP8B "Python 3 – Try It Online")
Could use a lot of golfing but I'm pretty happy with this answer. Tested on all 10 example cases.
-9 bytes thanks to Neil
[Answer]
# [Wolfram Language (Mathematica)](https://www.wolfram.com/wolframscript/), ~~267~~ 246 bytes
```
Reverse[R=StringReplace@{"("->"[",")"->"]","..."->"!",a:(WordCharacter|"_")..:>"\""<>a<>"\""},3]@ToString[a@ToExpression@R@#2//.a_String@b___:>a~q~b/.p@@@#//.a_?(FreeQ[_!])!:>(a//.s_/;FreeQ[s,p,{3,∞}]:>s~Thread~p/.p->(##&))/.q->Construct]&
a=""
```
[Try it online!](https://tio.run/##rVTditNAGL3vU7QTKBlI89O9i@0YN1gQRLS74EUcwrfpZBtok@zMVIQ0ufYpfDhfpH5J6tK1roj2IuTjHOac8538bEGvxRZ0lsAhnR@W4rOQSkTL@Y2WWX6/FOUGEhFUxCQTRiJiEdoOHAfbtttxRCzwzY@FXIVrkJBoIfckJtS2fUY@ETJjMOuG2rriwW3RC0eA4@svpRRKZUUeLANj6jg2xD0d3MVx7DNoHpo7xy6DIDA69qW5kEJ8iOIRpyOfmYCoip0XPaqs0qqurO9fv9XcZ6q5XUsBq6ZEhQkzDWNMqWM/TFhY5ErLXaL5eABzQg7v0VNHRhRNOZ@wx4wp2lpv8nKnF4Xccj5ubhLIm2pQzfYE5L1ysYCKvHJxt8FwOOywaYddu9jQU8JriXrPEOkPtwUifxEx71Jiqdkh9MJ6KEcvpBe61vBnf/00fTYtKnlnSr3FtXfuHbZEiMRp9qOd93deJ88Xk/5rsFOVjjZT@n9aaWwmv1U4O/jLKscS2rL/8GYs8MMvZAYbPPs2Uxpv@O8QoMXq3W6zebrRM5u0edv@z9d3HzPQ40XqQX34AQ "Wolfram Language (Mathematica) – Try It Online")
As far as I can tell there's no built-in way to `Thread` beyond the first level (or `Thread` heads, for that matter).
```
a="" (* ensures Reverse[R,3] works properly *)
R=StringReplace@{ (* parses input: *)
"("->"[",")"->"]", (* convert brackets to mathematica-style *)
"..."->"!", (* `...` is costly to manipulate, so instead use something that isn't. *)
a:(WordCharacter|"_")..:>"\""<>a<>"\""}; (* wrap symbols in quotes so they won't evaluate. *)
a@ToExpression@R@# (* parse input and wrap it with "" to allow multiple outputs *)
//.a_String@b___:>a~q~b (* convert expressions to a form suitable for calling Thread *)
/.p@@@# (* substitute packed arguments *)
//.a_?(FreeQ[_!])!]:> (* expand ...s from the bottom up: *)
(a//.s_/;FreeQ[s,p,{3,∞}]:>s~Thread~p (* thread over packed arguments from the bottom up, *)
/.p->(##&)) (* and unpack into sequences. *)
/.q->Construct (* convert back into an expression *)
Reverse[R,3]@ToString[ % ] (* convert to c-style output. *)
```
] |
[Question]
[
A [dual graph](https://en.wikipedia.org/wiki/Dual_graph) is defined such that for every "face" in a graph `G`, there is a corresponding vertex in the dual graph, and for every edge on the graph `G`, there is an edge in the dual graph connecting the vertices corresponding to the two faces on either side of the edge of the original graph. Note that the faces on both side may be the same face, for example the graph consisting of 2 vertices connected by a single edge (see case 3).
Here is a shamelessly borrowed example from Wikipedia:
[](https://i.stack.imgur.com/dPVR9.png)
Your goal is given a graph, find a dual graph for that graph. Note that there may not necessarily be a unique dual graph for a given graph; you need only find one. Assume all input graphs are undirected and planar.
# Input
Assume all vertices of the input graph have some consecutive integer numbering starting at any beginning integer value of your choice. An edge is described by an unordered pair of integers denoting the vertices the edge connects. For example, the blue graph shown above could be described with the following unordered multiset of edges (assuming the numbering of vertices starts at 0):
```
[(0,1), (0,2), (1,2), (2,3), (1,3), (1,4), (4,3)]
```
An alternative way to describe a multigraph is via an adjacency list. Here is an example adjacency list for the above graph:
```
[0:(1,2), 1:(0,2,3,4), 2:(0,1,3), 3:(1,2,4), 4:(1,3)]
```
Your program must take as input a multigraph of edges from any source (stdio, function parameter, etc.). You may assume the input graph is connected. You may use any notation desired so long as the no additional non-trivial information is communicated to your program. For example, having an extra parameter denoting the number of input edges is perfectly acceptable, but passing in a full or partially formed dual graph as an extra parameter is not. Similarly, passing in an unordered multiset of edges, adjacency list, or adjacency matrix is fine.
# Output
The output of your program should be in one of the formats allowed for the input; it needs not be the same as the input format. The output may be to any sink desired (stdio, return value, output parameter, etc.).
# Examples
All following examples use unordered multisets of edges with 0-based indices. One possible output is given. As a side note, all of the test case outputs are also valid inputs for your program, and an example output is the corresponding input.
**case 1:**
```
input:
[(0,1), (0,2), (1,2), (2,3), (1,3), (1,4), (4,3)]
output:
[(0,1), (0,2), (1,0), (0,3), (0,3), (1,2), (2,3)]
```
**case 2:**
```
input:
[(0,1),(0,2),(1,2)]
output:
[(0,1),(0,1),(0,1)]
```
**case 3:**
```
input:
[(0,1)]
output:
[(0,0)]
```
**case 4:**
```
input:
[]
output:
[]
```
**case 5:**
```
input:
[(0,1),(0,2),(2,1),(3,1),(3,4),(2,4)]
output:
[(0,2),(0,2),(1,0),(1,2),(1,2),(1,2)]
```
# Scoring
This is code golf; shortest code wins. Standard loopholes apply. You may use any built-ins not specifically designed to solve this problem.
[Answer]
# Python3, 416 bytes:
```
S=sorted
T=tuple
def C(n,o,l,p=[]):
if n==o and p:yield T(map(T,S(p)));return
for i in l[n]:
if(s:=S([n,i]))not in p:yield from C(i,o,l,p+[s])
def f(e):
K,s=0,{min(r,key=len)for i in e if(r:=[*C(i,i,e)])}
if not s and e:return[(0,0)]
E={(K:=K+1):set(i) for i in s}
l=[((a,b),j)for a in E for b in E if a<b and(j:=E[a]&E[b])]
return[(0,i)for i in E for _ in E[i]-{x for _,y in l for x in y}]+[a for a,_ in l]
```
[Try it online!](https://tio.run/##jVK7jhshFK09X0EVcWMS@VVEk1BFrlzaHUIWYxgFBwMCLO3I2m93eGzW2@wmzdz3Oedexk/pl7Prbz7c73saXUhKdgeart6oTqoR/cSWOGKIp4xD3yE9IkupQ8JK5PtJKyPRAV@Exweyxx4AvgeVrsF2aHQBaaQtMszyPJpncezpHjNLNAewLpXqX5QxuEum041uziKHqmDEqhDvSKQLcrtoiwP5rSZqlIVXClXAQ0/Z54KgiQIOz01tZolVruqbMoYXZAG8Q1t6w7ue7uZL6KNKWMNDc8zThjKMBRmAnCuTKIVt7Rmam/HFj6Gg43NPt0zwT1s28AL@4NIPmW34WF2m@ZfbU0uQqd6pBk/FnZ75nIkaC1L7Db/XC52cMeqUtLMR6YvPL4bylcTVJKlPqV4suaOQ56PRMWGTbzeTiL5twqUC3ayht11MbpvJvMBX4b3K@wxQE8NrQuREWwpVEAld54O2CY/4LWNZeQkEZbMqZtnMiqxb9GI2xWxylP8E@Aio4VSYf7S@X/5PjlX11y/fTc1sPmZd1PL9Dw)
] |
[Question]
[
This challenge is inspired by a picture that often roams on Facebook that looks like [this](https://i.stack.imgur.com/SM0I2.jpg). Except our base square will look more like this:
```
┌─┬───┬─┐
├─┼─┬─┼─┤
├─┼─┴─┼─┤
├─┼─┬─┼─┤
└─┴─┴─┴─┘
```
The square is made out of `n x m` 1x1 square, you have to count how many sub-squares (1x1, 2x2, 3x3, 4x4, 5x5, etc.) can fit within that square. Squares can be missing some grid lines (like in the example above) or be complete like in the example bellow. Which means a mathematical breakdown is *not* possible (as far as I know).
## Inputs:
* The amount of lines (`n`) of input to build the square;
* A square made from the following characters: `─` `┐` `┌` `└` `┴` `┘` `┬` `├` `┤` `┼` `|` across `n` lines of input.
## Output:
* The amount of squares of any size that can fit within the input square (we only want a single number here, not a number for each size).
## Winning criterion:
The smallest answer (number of bytes) wins.
## Test Cases:
**In:**
```
5
┌─┬─┬─┬─┐
├─┼─┼─┼─┤
├─┼─┼─┼─┤
├─┼─┼─┼─┤
└─┴─┴─┴─┘
```
**Out:** 30
---
**In:**
```
3
┌─┬─┐
├─┼─┤
└─┴─┘
```
**Out:** 5
---
**In:**
```
5
┌─┬─┐
├─┴─┤
├───┤
├─┬─┤
└─┴─┘
```
**Out:** 7
---
**In:**
```
4
┌─┬─┬─┬─┬─┬─┐
├─┼─┼─┼─┼─┼─┤
├─┼─┼─┼─┼─┼─┤
└─┴─┴─┴─┴─┴─┘
```
**Out:** 32
---
**In:**
```
2
┌─┐
└─┘
```
**Out:** 1
---
**In:**
```
4
┌─┬─┬─┬─┬─┬─┐
├─┴─┼─┼─┼─┴─┤
├─┬─┼─┼─┼─┬─┤
└─┴─┴─┴─┴─┴─┘
```
**Out:** 22
[Answer]
# JavaScript (ES6), [292](https://mothereff.in/byte-counter#%28h%2Cz%29%3D%3E%28o%3D%3E%7Br%3Dp%3D%3E%22%20%29%2C%E2%94%8C%28%E2%94%80%E2%94%90%E2%94%AC%27%E2%94%94%E2%94%82%E2%94%9C%E2%94%98%E2%94%B4%E2%94%A4%E2%94%BC%22.search%28z%5Bp%5D%29%3Bk%3D%28p%2Cd%2Cm%29%3D%3Er%28p%29%26r%28p%2Bs%2Ad%29%26m%3Bfor%28q%3Ds%3D0%3B%2B%2Bs%3Co%2F2%26s%3Ch%3B%29for%28y%3D0%3By%3C%28h-s%29%2Ao%3By%2B%3Do%29for%28x%3D0%3Bx%3Co-s%2A2%3Bq%2B%3D!n%2Cx%2B%3D2%29for%28n%3Di%3D0%2Ct%3Dx%2Cu%3Dy%3Bi%3C%3Ds%3Bt%2B%3D2%2Cu%2B%3Do%2Ci%2B%2B%29n%3Dn%7Ci%3Cs%26%28!k%28t%2By%2Co%2C1%29%7C!k%28x%2Bu%2C2%2C2%29%29%7Ci%3E0%26%28!k%28t%2By%2Co%2C4%29%7C!k%28x%2Bu%2C2%2C8%29%29%3B%7D%29%28-~z.search%60%0A%60%29%7Cq%0A) bytes ~~306 325~~
**Edit** I did the byte count totally wrong, ~~corrected now thx <http://bytesizematters.com/>~~ correct for the last time I hope thx Cᴏɴᴏʀ O'Bʀɪᴇɴ see <https://goo.gl/LSHC1U> (and 1 byte less using a literal newline insteads of '\n')
```
(h,z)=>(o=>{r=p=>" ),┌(─┐┬'└│├┘┴┤┼".search(z[p]);for(q=s=0;++s<o/2&s<h;)for(y=0;y<(h-s)*o;y+=o)for(x=0;x<o-s*2;q+=!n,x+=2)for(n=i=0,t=x,u=y;i<=s;t+=2,u+=o,i++)n|=i<s&(!(r(t+y)&r(t+y+s*o)&1)|!(r(x+u)&r(x+u+s*2)&2))|i>0&(!(r(t+y)&r(t+y+s*o)&4)|!(r(x+u)&r(x+u+s*2)&8))})(-~z.search`
`)|q
```
Longer than I expected (probably a few more byte can be shaved off)
All possible squares are checked and counted.
The `r` function map each character to a bitmap having
* 1 : horizontal line center to right
* 2 : vertical line center to bottom
* 4 : horizontal line center to left
* 8 : vertical line center to top
A square of any size must have
* 4 in all cells except the first in top and bottom row
* 1 in all cells except the last in top and bottom row
* 8 in all cells except the first in leftmost and rightmost column
* 2 in all cells except the last in leftmost and rightmost column
**Test**
```
f=(h,z)=>(o=>{r=p=>" ),┌(─┐┬'└│├┘┴┤┼".search(z[p]);k=(p,d,m)=>r(p)&r(p+s*d)&m;for(q=s=0;++s<o/2&s<h;)for(y=0;y<(h-s)*o;y+=o)for(x=0;x<o-s*2;q+=!n,x+=2)for(n=i=0,t=x,u=y;i<=s;t+=2,u+=o,i++)n=n|i<s&(!k(t+y,o,1)|!k(x+u,2,2))|i>0&(!k(t+y,o,4)|!k(x+u,2,8));})(-~z.search`
`)|q
console.log=(...x)=>O.textContent+=x+'\n'
// Less golfed
Uf=(h,z)=>{
o=-~z.search`\n`;
w=o/2;
r=p=>" ),┌(─┐┬'└│├┘┴┤┼".search(z[p]);
k=(p,d,m)=>r(p)&r(p+s*d)&m;
for(q=s=0;++s<w&s<h;)
for(y=0;y<(h-s)*o;y+=o)
for(x=0;x<(w-s)*2;q+=!n,x+=2)
for(n=i=0,t=x,u=y;i<=s;t+=2,u+=o,i++)
n|=i<s&(!k(t+y,o,1)|!k(x+u,2,2))
|i>0&(!k(t+y,o,4)|!k(x+u,2,8));
return q
}
;[[5,`┌─┬───┬─┐
├─┼─┬─┼─┤
├─┼─┴─┼─┤
├─┼─┬─┼─┤
└─┴─┴─┴─┘`,20]
,[5,`┌─┬─┬─┬─┐
├─┼─┼─┼─┤
├─┼─┼─┼─┤
├─┼─┼─┼─┤
└─┴─┴─┴─┘`,30]
,[3,`┌─┬─┐
├─┼─┤
└─┴─┘`,5]
,[5,`┌─┬─┐
├─┴─┤
├───┤
├─┬─┤
└─┴─┘`,7]
,[4,`┌─┬─┬─┬─┬─┬─┐
├─┼─┼─┼─┼─┼─┤
├─┼─┼─┼─┼─┼─┤
└─┴─┴─┴─┴─┴─┘`,32]
,[2,`┌─┐
└─┘`,1]
,[4,`┌─┬─┬─┬─┬─┬─┐
├─┴─┼─┼─┼─┴─┤
├─┬─┼─┼─┼─┬─┤
└─┴─┴─┴─┴─┴─┘`,22],
,[6,`┌─┬─────┐
├─┼─┬─┐ │
│ ├─┼─┼─┤
│ └─┼─┼─┤
│ └─┼─┤
└─────┴─┘`,12],
,[6,`┌─┬─┬─┬─┐
├─┴─┼─┼─┤
│ └─┼─┤
├─┬─┬─┼─┤
├─┼─┼─┼─┤
└─┴─┴─┴─┘`,23]]
.forEach(t=>{
var r=t[0],a=t[1],k=t[2],x=f(r,a)
console.log(x==k?'OK '+x:'KO '+x+' Expected '+k,'\n'+a)
})
```
```
<pre id=O></pre>
```
] |
[Question]
[
In [ValiDate ISO 8601 by RX](https://codegolf.stackexchange.com/questions/54555/validate-iso-8601-by-rx), the challenge was to use only standard regular expressions to **validate standard date formats *and* values** (the former is a common job for RX, the latter was unusual). The winning answer used 778 bytes. This challenge is to beat that using any language of your choosing, but **without special date functions or classes**.
# Challenge
Find the shortest code that
1. validates every possible date in the [*Proleptic*](https://en.wikipedia.org/wiki/Proleptic_Gregorian_calendar) Gregorian calendar (which also applies to all dates before its first adoption in 1582),
2. does not match any invalid date and
3. does not use any predefined functions, methods, classes, modules or similar for handling dates (and times), i.e. relies on string and numeric operations.
## Output
Output is truthy or falsey.
It’s not necessary to output or convert the date.
## Input
Input is a single string in any of 3 expanded [ISO 8601](http://en.wikipedia.org/wiki/ISO_8601) date formats – no times.
The first two are `±YYYY-MM-DD` (year, month, day) and `±YYYY-DDD` (year, day). Both need special-casing for the leap day. They are naively matched separately by these extended RXs:
```
(?<year>[+-]?\d{4,})-(?<month>\d\d)-(?<day>\d\d)
(?<year>[+-]?\d{4,})-(?<doy>\d{3})
```
The third input format is `±YYYY-wWW-D` (year, week, day). It is the complicated one because of the complex leap week pattern.
```
(?<year>[+-]?\d{4,})-W(?<week>\d\d)-(?<dow>\d)
```
# Conditions
A **leap year** in the Proleptic Gregorian calendar contains the **leap day** `…-02-29` and thus it is 366 days long, hence `…-366` exists. This happens in any year whose (possibly negative) ordinal number is divisible by 4, but not by 100 unless it’s also divisible by 400.
**Year zero** exists in this calendar and it is a leap year.
A **long year** in the ISO week calendar contains a 53rd week `…-W53-…`, which one could term a “**leap week**”. This happens in all years where 1 January is a Thursday and additionally in all leap years where it’s a Wednesday. `0001-01-01` and `2001-01-01` are Mondays. It turns out to occur every 5 or 6 years usually, in a seemingly irregular pattern.
A year has at least 4 digits. Years with more than 10 digits do not have to be supported, because that’s close enough to the age of the universe (ca. 14 billion years). The leading plus sign is optional, although the actual standard suggests it should be required for years with more than 4 digits.
Partial or truncated dates, i.e. with less than day-precision, must not be accepted.
Separating hyphens `-` are required in all cases.
(These preconditions make it possible for leading `+` to be always optional.)
# Rules
This is code-golf. The shortest code in bytes wins.
Earlier answer wins a tie.
# Test cases
## Valid tests
```
2015-08-10
2015-10-08
12015-08-10
-2015-08-10
+2015-08-10
0015-08-10
1582-10-10
2015-02-28
2016-02-29
2000-02-29
0000-02-29
-2000-02-29
-2016-02-29
+2016-02-29
200000-02-29
-200000-02-29
+200000-02-29
2016-366
2000-366
0000-366
-2000-366
-2016-366
+2016-366
2015-081
2015-W33-1
2015-W53-7
+2015-W53-7
+2015-W33-1
-2015-W33-1
2015-08-10
```
The last one is optionally valid, i.e. leading and trailing spaces in input strings may be trimmed.
## Invalid formats
```
-0000-08-10 # that's an arbitrary decision
15-08-10 # year is at least 4 digits long
2015-8-10 # month (and day) is exactly two digits long, i.e. leading zero is required
015-08-10 # year is at least 4 digits long
20150810 # though a valid ISO format, we require separators; could also be interpreted as a 8-digit year
2015 08 10 # separator must be hyphen-minus
2015.08.10 # separator must be hyphen-minus
2015–08–10 # separator must be hyphen-minus
2015-0810
201508-10 # could be October in the year 201508
2015 - 08 - 10 # no internal spaces allowed
2015-w33-1 # letter ‘W’ must be uppercase
2015W33-1 # it would be unambiguous to omit the separator in front of a letter, but not in the standard
2015W331 # though a valid ISO format we require separators
2015-W331
2015-W33 # a valid ISO date, but we require day-precision
2015W33 # though a valid ISO format we require separators and day-precision
2015-08 # a valid ISO format, but we require day-precision
201508 # a valid but ambiguous ISO format
2015 # a valid ISO format, but we require day-precision
```
## Invalid dates
```
2015-00-10 # month range is 1–12
2015-13-10 # month range is 1–12
2015-08-00 # day range is 1–28 through 31
2015-08-32 # max. day range is 1–31
2015-04-31 # day range for April is 1–30
2015-02-30 # day range for February is 1–28 or 29
2015-02-29 # day range for common February is 1–28
2100-02-29 # most century years are non-leap
-2100-02-29 # most century years are non-leap
2015-000 # day range is 1–365 or 366
2015-366 # day range is 1–365 in common years
2016-367 # day range is 1–366 in leap years
2100-366 # most century years are non-leap
-2100-366 # most century years are non-leap
2015-W00-1 # week range is 1–52 or 53
2015-W54-1 # week range is 1–53 in long years
2016-W53-1 # week range is 1–52 in short years
2015-W33-0 # day range is 1–7
2015-W33-8 # day range is 1–7
```
[Answer]
# JavaScript (ES6), 236
236 bytes allowing negative 0 year (`-0000`). Returns true or false
```
s=>!!([,y,w,d]=s.match(/^([+-]?\d{4,})(-W?\d\d)?(-\d{1,3})$/)||[],n=y%100==0&y%400!=0|y%4!=0,l=((l=y-1)+8-~(l/4)+~(l/100)-~(l/400))%7,l=l==5|l==4&!n,+d&&(-w?d>`0${2+n}0101001010`[~w]-32:w?(w=w.slice(2),w>0&w<(53+l)&d>-8):d[3]&&d>n-367))
```
Adding the check for negative 0 cut 2 bytes but adds 13. Note that in javascript the numeric value `-0` exists, and it is special cased to be equal to 0, but `1/-0` is `-Infinity`. This versione returns 0 or 1
```
s=>([,y,w,d]=s.match(/^([+-]?\d{4,})(-W?\d\d)?(-\d{1,3})$/)||[],n=y%100==0&y%400!=0|y%4!=0,l=((l=y-1)+8-~(l/4)+~(l/100)-~(l/400))%7,l=l==5|l==4&!n,+d&&(-w?d>`0${2+n}0101001010`[~w]-32:w?(w=w.slice(2),w>0&w<(53+l)&d>-8):d[3]&&d>n-367))&!(!+y&1/y<0)
```
**Test**
```
Check=
s=>!! // to obtain a true/false
(
// parse year in y, middle part in w, day in d
// day will be negative with 1 or 3 numeric digits and could be 0
// week will be '-W' + 2 digits
// month will be negative with2 digits and could be 0
// if the date is in format yyyy-ddd, then w is empty
[,y,w,d] = s.match(/^([+-]?\d{4,})(-W?\d\d)?(-\d{1,3})$/) || [],
n = y%100==0 & y%400!=0 | y%4!=0, // n: not leap year
l = ((l=y-1) + 8 -~(l/4) +~(l/100) -~(l/400)) % 7,
l = l==5| l==4 & !n, // l: long year (see http://mathforum.org/library/drmath/view/55837.html)
+d && ( // if d is not empty and not 0
-w // if w is numeric and not 0, then it's the month (negative)
? d > `0${2+n}0101001010`[~w] - 32 // check month length (for leap year too)
: w // if w is not empty, then it's the week ('-Wnn')
? ( w = w.slice(2), w > 0 & w < (53+l) & d >- 8) // check long year too
: d[3] && d > n-367 // else d is the prog day, has to be 3 digits and < 367 o 366
)
)
console.log=x=>O.textContent += x +'\n'
OK=['1900-01-01','2015-08-10','2015-10-08','12015-08-10','-2015-08-10','+2015-08-10'
,'0015-08-10','1582-10-10','2015-02-28','2016-02-29','2000-02-29'
,'0000-02-29','-2000-02-29','-2016-02-29','+2016-02-29','200000-02-29'
,'-200000-02-29','+200000-02-29','2016-366','2000-366','0000-366'
,'-2000-366','-2016-366','+2016-366','2015-081','2015-W33-1'
,'2015-W53-7','+2015-W53-7','+2015-W33-1','-2015-W33-1','2015-08-10']
KO=['-0000-08-10','15-08-10','2015-8-10','015-08-10','20150810','2015 08 10'
,'2015.08.10','2015–08–10','2015-0810','201508-10','2015 - 08 - 10','2015-w33-1'
,'2015W33-1','2015W331','2015-W331','2015-W33','2015W33','2015-08','201508'
,'2015','2015-00-10','2015-13-10','2015-08-00','2015-08-32','2015-04-31'
,'2015-02-30','2015-02-29','2100-02-29','-2100-02-29','2015-000'
,'2015-366','2016-367','2100-366','-2100-366','2015-W00-1'
,'2015-W54-1','2016-W53-1','2015-W33-0','2015-W33-8']
console.log('Valid')
OK.forEach(x=>console.log(Check(x)+' '+x))
console.log('Not valid')
KO.forEach(x=>console.log(Check(x)+' '+x))
```
```
<pre id=O></pre>
```
] |
[Question]
[
# Bob the Bowman
```
o
/( )\ This is Bob.
L L Bob wants to be an archer.
#############
.
/ \ <--- bow So he bought himself a
(c -)-> <--- arrow nice longbow and is about
( )/ <--- highly focused Bob shoot at a target.
L L
#############
___________________________________________________________________________________________
sky
Bob is a smart guy. He already knows what angle and
velocity his arrow has / will have. But only YOU know
the distance to the target, so Bob doesn't know if he
will hit or miss. This is where you have to help him.
. +-+
/ \ | |
(c -)-> | |
( )/ +++
L L |
###########################################################################################
```
---
## Task
Your task is to render an ASCII art picture of Bob hitting or missing the target. For the calculation:
* Your program will receive `arrow_x,angle,velocity,distance` as comma-separated input in any order you wish.
* One ASCII character equals `1m`.
* The first character in the last line has the coordinates `(0,0)`, so the ground (rendered as `#`) is at `y=0`.
* Bob always stands on the ground, his `y` position does not change.
* There is no max `y`. However, the arrows apex should fit within the rendered picture.
* All input is provided as decimal integer.
* During calculation, assume the arrow is a point.
* The arrow origin is the arrow head `>` of a shooting Bob (see above). So given `arrow_x`, you have to calculate `arrow_y`. The left foot of Bob in the output has to match the `x` coord. of the shooting Bob.
* `distance` is the `x` coordinate of the target's *foot*. (ie. the middle of the target).
* All measurements are supplied in meters and degrees respectively.
* Attention: *The shooting Bob is never rendered, only used for calculations! See below for the two valid output-Bobs*
* Hitting the target means the arrows path crosses either one of the two leftmost target walls (`|`) (That is either (distance-1,3) or (distance-1,4). If at some point the arrow is within those 2m², place the X instead of the wall it hits. The target is always the same height and only its x position can change.). Corner hits or an arrow falling from the sky onto the target does not count.
* Standard earth g applies (9.81 m/s^2).
* `distance+1` is the end of the field, after that, everything is a miss and no arrow should be rendered.
* If the arrow hits the target in any other way (`distance-1` etc.), no arrow should be rendered.
## Miss
This is an example rendering of Bob missing (arrow enters ground at 34m, angle is 45°, time in air is 10s, velocity is ~50 - but there are a lot more possible inputs to cause this output. Just show your program uses the usual formulas to calculate physically "accurate" results.):
```
+-+
| |
c\ | |
/( ) v +++
L L | |
###########################################################################################
```
## Hit
This is an example rendering of Bob scoring (arrow enters target (= crosses its path)):
```
+-+
>--X |
\c/ | |
( ) +++
L L |
###########################################################################################
```
## Example
* `arrow_x` is 7. `arrow_y` is always 3.
* `angle` is `30°` or `0.523598776` radians.
* `velocity` is `13m/s`.
* `distance` is 20.
So in order to hit the target, the arrow has to cross `(19,3)` or `(19,4)`. Everything else will be a miss. In this case, the arrow will enter the ground (means `y` will be `<1.0`) at `12.9358m = ~13m` after `1.149s`.
---
## Limits & Scoring
* This is [code-golf](/questions/tagged/code-golf "show questions tagged 'code-golf'"), so the shortest solution wins. There are no bonuses.
* Your *program* (as in *not function*) must accept input in the format described above, additional input is not permitted.
* You don't have to handle wrong/pointless/impossible inputs.
* Print to whatever is the shortest reasonable output for your language (std, file, ...).
* I don't care about trailing whitespace.
* *Tip:* Width of output is `distance+2`. The height is `apex+1`.
[Answer]
# Ruby, 482
```
include Math
def f s,e,l
[s,' '*(l-s.size-e.size),e].join
end
alias p puts
X,o,V,d=$*[0].split(?,).map &:to_i
o*=PI/180
L=X+d
B='| |'
S=''
G=' L L'
p f S,'+-+',L
d.times{|x|y=3+x*tan(o)-(9.81*x**2)/(2*(V*cos(o))**2)
if x==d-1&&(3..5)===y
s='>--X |'
m=(3..4)===y
p f S,m ?B: s,L
p f ' \c/',m ?s: B,L
p f ' ( )',?+*3,L
p f G,'| ',L
elsif y<=1 || x==d-1
p f S,B,L
p f ' c\\',B,L
print f '/( )', y<1? 'V':' ',x
p f S,?+*3,L-x
print f G, y<1? '|':' ',x
p f S,'| ',L-x
break
end}
p ?#*L
```
## Ungolfed
```
include Math
def fill s,e,l
[s,' '*(l-s.size-e.size),e].join
end
arrow_x,angle,velocity,distance = $*[0].split(',').map(&:to_i)
angle *= PI/180
length=arrow_x+distance
loss = '| |'
puts fill '','+-+',length
distance.times { |x|
y = 3 + x*tan(angle) - (9.81*x**2)/(2*(velocity*cos(angle))**2)
if x == distance-1 && (3..5)===y
puts fill '',(3..4)===y ? '| |':'>--X |',length
puts fill ' \c/',(3..4)===y ? '>--X |':'| |',length
puts fill ' ( )','+++',length
puts fill ' L L','| ',length
elsif y<=1 || x==distance-1
puts fill '',loss,length
puts fill ' c\\',loss,length
print fill '/( )', y<1? 'v': ' ', x
puts fill '','+++',length-x
print fill ' L L', y<1? '|': ' ', x
puts fill '',' | ',length-x
break
end
}
puts ?#*length
```
### Method
The main equation here is:
[](https://i.stack.imgur.com/OtNC8.png)
Note: image taken from <https://en.wikipedia.org/wiki/Trajectory_of_a_projectile>
Where,
```
y0: initial height (of arrow)
Ө: the angle
x: the position of the arrow
g: gravity (9.81)
v: velocity
```
What I'm doing is to loop through numbers from 0 to (distance -1) and in every iteration check to see if the arrow hits the ground (or the target)
] |
[Question]
[
**Closed**. This question needs [details or clarity](/help/closed-questions). It is not currently accepting answers.
---
**Want to improve this question?** Add details and clarify the problem by [editing this post](/posts/55239/edit).
Closed 2 years ago.
[Improve this question](/posts/55239/edit)
## Introduction
On BBC Radio 2, on Saturdays there's a show hosted by Tony Blackburn called [**Pick of the Pops**](http://www.bbc.co.uk/programmes/b006wqx7). Here, Tony selects a random week from a random year (in the range 1960-1989), and plays the songs which were in the top 20 charts at the time.
## Challenge
Given a list of songs played on one Pick of the Pops episode, you must determine the year which Tony has chosen.
## Further Information
### Input
The input will be given as a string (either by STDIN or function arguments), with each list item separated by a comma.
The input will sorted with the number one single first, carrying on in order until the list ends with the number 20 single.
On the actual show, Blackburn plays the charts for two different years. This will not be the case for your input, only the chart for your one year will be supplied.
If song usually has a comma in its name, then the comma will be omitted.
### Output
Your output should simply be the year in the format `YYYY` (`1989`, `2365`, `1901`).
If for any reason, multiple years are found (say if the charts are form the first week of the year), then either select the *first* year or output both, comma separated.
### Rules
You can read from either a file or the internet.
If you use the internet, you must only use pages on the website `officialcharts.com`.
***Note:* if you read from a Wikipedia page, the page must have been created before the 23rd of August 2015.**
The charts will be from the *national UK charts*, not international or of any other country.
Your output must be in the range of 1960 - 1989.
## Examples
### Input
```
Ticket to Ride,Here Comes the Night,The Minute You're Gone,Concrete and Clay,Little Things,Catch the Wind,For Your Love,King of the Road,The Last Time,Pop Go the Workers,Bring It On Home to Me,Stop in the Name of Love,Times They Are A-Changin',You're Breakin' My Heart,I Can't Explain,I'll Be There,Everybody's Gonna Be Happy,It's Not Usual,A World of Our Own,True Love Ways
```
### Output
```
1965
```
## Winning
The person with the shortest program in bytes wins.
## Note
At the moment, I'm still downloading all of the chart information, but you can use the following Python 2 code to retrieve the necessary information and create the file. (Requires the *requests* module)
```
import requests, re, datetime, time
date = datetime.date(1960,1,1)
prevyear=0
year = 1960
delay = # Set the delay yourself. So far 4 seconds still makes the download fail
while date.year != 1990:
response = requests.get("http://www.officialcharts.com/charts/singles-chart/%d%02d%02d"%(date.year, date.month, date.day)).text
time.sleep(delay)
tags = re.findall("<a href=\"/search/singles/.+\">.+</a>", response)[:20]
top20s = []
for i in tags[:]:
tag = re.sub("<a href=\"/search/singles/.+\">", "", i)
tag = re.sub("</a>","",tag)
top20s.append(tag)
top20s = list(map(lambda x:x.replace(",",""), top20s))
with open("songs.txt", "a") as f:
if year != prevyear:
string = str(year)+"\n"
else:
string = ""
chart = ",".join(top20s)
f.write(string+chart+"\n")
prevyear = year
date += datetime.timedelta(days=7)
year = date.year
```
[Answer]
## C# (~~277, 271,~~ 223 compacted bytes)
After six years, this deserves an answer, so I'm going to make some assumptions:
* The data is stored in the file: `C:\songs.txt`.
* The songs for each week are stored on a new line in the following format:
+ `yyyy:song,song,song,...`
---
```
var @in = Console.ReadLine();
var d = File.ReadAllText(@"C:\songs.txt");
foreach (var w in d.Split('\n')) {
var wd = w.Split(':');
if (wd[1].Split(',').Any(a => @in.Split(',').ToList().Any(i => i.Equals(a)))) {
Console.Write(wd[0]);
break;
}
}
```
---
***Note**: Compacted in this case means removing all line breaks and unnecessary whitespace. I'm retaining proper formatting for the sake of readability.*
] |
[Question]
[
## Introduction
[Tangrams](http://en.wikipedia.org/wiki/Tangram) are a classic puzzle involving arranging/fitting blocks into various shapes. From the Chinese 七巧板 - literally meaning "seven boards of skill". Let's take this idea and use the seven [Tetrominos](http://en.wikipedia.org/wiki/Tetris#Gameplay) pieces to fill a grid.
## Challenge
Write a function or program that takes an array of grid coordinates as input, and outputs a completed 10 by 20 grid filled with Tetris pieces except in the specified coordinates.
Optimize your score by attempting to keep the distribution of pieces uniform.
## Criteria
Use [this pastebin](http://pastebin.com/0QAgFT5f) of coordinates to accomplish your task. There are five sets of coordinates. Feel free to modify the format in which the coordinates are written, but not the values.
Data set #2 cannot be solved - in this case, simply output the grid with input cells filled in (i.e., `X`'s where the holes are).
## Input
Grid coordinates represent 'holes' in the grid. These are cells which cannot contain any part of a Tetromino.
**Grid coordinates:**
```
(0,0), (1,0), (2,0), ... (9,0)
(0,1), (1,1), (2,1), ... (9,1)
.
.
.
(0,19), (1,19), (2,19), ... (9,19)
```
* Use your programming language's array style of choice to input the coordinates.
* Represent holes in the grid with an `X` or other [printable ASCII](http://en.wikipedia.org/wiki/ASCII#ASCII_printable_characters).
## Output
Using a standard Tetris grid size of **10 cells wide by 20 cells tall**, print a solution grid if and only if the grid can be filled completely and perfectly using Tetromino pieces.
Pieces constructed with letters `I`, `O`, `L`, `J`, `T`, `Z`, `S` as follows:
```
I
I L J
I OO L J T ZZ SS
I OO LL JJ TTT ZZ SS
```
---
## Example
Output solution example with no input coordinates:
```
ZZIIIILLLI
JZZTTTLLLI
JJJSTLOOLI
SZZSSLOOLI
SSZZSLLJJI
TSOOSLLJII
TTOOSSLJII
TZOOSSLZII
ZZOOSSZZII
ZJJJJSZLLI
TTTJJOOILI
ITZJJOOILI
IZZTTTLIII
IZOOTZLIII
IJOOZZLLII
LJJJZSSTII
LLLTSSTTTI
LLLTTSSZJI
OOLTSSZZJI
OOIIIIZJJI
```
With distribution as follows:
```
I
I L J
I OO L J T ZZ SS
I OO LL JJ TTT ZZ SS
11 6 8 6 6 7 6
```
---
## Notes
Coordinates represent a single `X` and `Y` position on the grid. The grid is 0 based, meaning coordinate `(0,0)` should either be the top left or the bottom left cell, author's choice.
Bricks can:
* be selected at author's discretion.
* be rotated as author sees fit.
* be placed on the grid anywhere at author's discretion (aka: no Tetris gravity)
Bricks cannot:
* be placed outside the bounds of the grid.
* overlap an existing brick or hole in the grid.
* be a non-standard Tetris tetromino piece.
---
## Scoring
Your score is in the format:
**( 1000 - [bytes in code] ) \* ( M / 10 + 1 )**
Where M is a multiplier for the distribution of pieces used in your solution sets.
Highest score by the Ides of March wins.
To calculate M, add the lowest individual tetromino distribution value for each set and then take the average rounded down to calculate M.
For example:
```
Set 1: 5
Set 2: 4
Set 3: 5
Set 4: 6
Set 5: 3
```
6 + 4 + 5 + 4 + 4 = 21 / 5 = 4.6
So you would use `4` as your **M** value.
Note: If a set has no solution, do not factor that set into calculating M, since it would have no tetromino distribution.
[Answer]
# [Python 3](https://docs.python.org/3/), 819 bytes, M=0, Score=*181*
This is a brute force DFS program. It builds a numpy array, and inserts all the inputted holes. It then takes the leftmost unfilled tile on the highest row that has one, and places a tetromino. Recursively, we now do it again - when we can't either we found a solution, or we backtrack and try another piece at the first opportunity.
This has an **M** of 0, since it tries to use pieces in a determined order, and almost always finds a solution without the last one in the list. I tried using a randomly ordered list each cycle to make a more even distribution, but I only got an **M** of 2, which wasn't worth the bytes required to import *random.shuffle*.
I can't comment the below code, since in my golfing I've long forgotten what much of it does. The general idea:
* Import numpy and itertools product, with 1-letter names
* Rename some builtins to be 1-letter functions, and define a lambda to save bytes
* Build the array of possible tetrominos as numpy nd-arrays, all rotations included
* In the recursive function:
+ Get the position of the unfilled tile desired, and cycle through the pieces list
+ For each piece, cycle through translations of it (moving it up and down)
+ If something doesn't work (piece goes off the board, hits another piece, hits a hole, etc.), try the next translation or the next entire piece
+ If it works, great. Try it, then recursively call the function.
+ If that path didn't work, it will return 'a', so we just try again. If it did work, it returns the board, and we pass it up the line.
* Finally, the program. We build the 10x20 board as a numpy array of 1's.
* The input is of the form *(x1, y1);(x2,y2);...* We put a 9 for each hole in it, then get the result of running the function on it.
* The print statement then displays either the successful result or the empty, original board line by line, substituting the appropriate letters or symbols for the numbers.
```
import numpy as n
from itertools import product as e
m,s=range,len
p=[n.rot90(a,k)for a,r in[([[2,2]]*2,1),([[3]*3,[1,3,1]],4),([[0]*4],2),([[1,1,6],[6]*3],4),([[7,1,1],[7]*3],4),([[4,4,1],[1,4,4]],2),([[1,5,5],[5,5,1]],2)]for k in m(r)]
o=lambda a:e(m(s(a)),m(s(a[0])))
def t(l,d=0):
g=list(zip(*n.where(l==1)))[0]
for a in p:
for u,v in o(a):
w,x=l.copy(),0
for r,c in o(a):
if a[r,c]!=1:
i,j=g[0]+r-u,g[1]+c-v
if any([i<0,i>19,j<0,j>9])or l[i,j]!=1:
x=1
break
w[i,j]=a[r,c]
if x==0:
if len(w[w==1]):
f=t(w,d+1)
if type(f)==str:continue
return f
return w
return'a'
b=n.ones((20,10))
b[list(zip(*[eval(k)[::-1]for k in input().split(';')]))]=9
a=t(b)
for r in(a,b)[type(a)==str]:
print(''.join(map(dict(zip([0,2,3,4,5,6,7,9,1],'IOTZSLJX-')).get,r)))
```
[Try it online!](https://tio.run/##VVLBbtswDD1bX@GdLKWMYTlpi2TT7hsG7LAdhgk6KImcKrElQ5brZj@f0XbWdheJfHyknki2l/jk3ep6tU3rQ0xd37SXVHepI1XwTWqjCdH7uktvhDb4Q7@PI8WQBjoRtDsaqI0jrZAuDz5uCqrhzCofUg0htU5SKUsolVqUwBmgt1KLFUgOK@BKwXrCCrVYKygnmwOHBwXyAXn/4o@IccQe32FrWE8Yx3ut3rLv4R5RPKf6JVOjmDNKSRsamCJe1LrZHXSqt4Y2tKOaMZhulMEYIwdTpZHWcBAF25LkKGrbRfrHtnTh8uHJBENrIThSMYEk01/H8i2SJ6@H59H3WHmEkgFeRJ3vfXuhDIoRGVkB9v@xElulWiKqPgg@I4mFkzjiK3dh2cNRcnW3Xz7fQsh2FyrtpwLsZ76BExqnzxvFsHYtMfNdneRF8Ju1C0afZ3uYWGJ@lMw1X4QoXuXgZOkgB/ysumlMKhHpAIc7zl5lxEtraMWE6GLY7r2L1vVmjgYT@@DSirxzBnKzMp2RnXC5d6ajtCyAF9j9nXxrtzTPuqZnJrfbJX@bo3VtHynLu7a2kWYfM4ZzU2JDNIrbMTJ1F1m4ijsmJ3l6lqfwF22wDrOy/OSR0uiWHux@flAWUOJernF3HuARNuN@ZV@@//z949vXX8uMsfxoIgSc/PX6Fw "Python 3 – Try It Online")
Sample test:
```
In: (1,1);(8,1);(4,4);(5,8);(4,11);(5,15);(1,18);(8,18)
Out:
IIIIOOOOLL
TXOOOOOOXL
TTOOOOOOTL
TOOIOOOOTT
TOOIXOOTTI
TTTITOOTTI
TTTITTTTII
OOTTTTTTII
OOTTTXOOII
TTTTOOOOII
TTTTOOOOII
TTTTXTOOII
ITTTTTTTII
ITTTTTTTII
IITTTLLTTI
IITOOXLTTI
IITOOTLTTI
IITTLTTTTI
IXTLLTJTXI
ILLLLLJJJI
```
] |
[Question]
[
```
0000000000000000000000000000000000000000000000000000000000000000000000
0000000000000000000000000000000000000000000000000000000000000000000000
0000000000000000000000000000000000000000000000000000000000000000000000
0000001111111111111100000000000000000011111111111111100000000000000000
0000001111111111111100000000000000000011111111111111100000000000000000
0000001111111111111100000000000000000011111111111111100000000000000000
0000001111111111111100000000000000000011111111111111100000000000000000
0000000000000000000000000000000000000011111111111111100000000000000000
0000000000000000000000000000000000000011111111111111100000000000000000
0000000000011111100000000000000000000011111111111111100000000000000000
0000000000011111100000000000000000000011111111111111100000000000000000
0000000000011111100000000000000000000011111111111111100000000000000000
0000000000000000000000000000000000000011111111111111100000000000000000
0000000000000000000000000000000000000011111111111111100000000000000000
0000000000000111111000000000000000000011111111111111100000000000000000
0000000000000100001000000111111000000011111111111111100000000010000000
0000000000000100001000000111111000000000000000000000011000000000000000
0000000000000111111000000111111000000000000000000000011000000000000000
0000000000000000000000000000111111000000000000000000000000000000000000
0000000000000000000000000000111111000000000000000000000000000000000000
0000000000000000000000000000000000000000000000000000000000000000000000
```
Your are given a 2 dimensional array of bytes of size m x n. It is guaranteed that all the bytes are 1's or 0's.
Find the number of rectangles represented by 1's when viewed in 2d, as shown above.
Only fully filled rectangles are considered for counting.
Rectangles must be surrounded by 0's unless they are on edge(1's diagonally touching rectangles are Okay though (see example.)).
For example, in above array there are 5 valid rectangles.
You can use any language.
[Answer]
### GolfScript, 107 characters
```
.n?):L;'1'/{,}%{1$+)}*;][]\{:A{{+}+[1L.~)-1]%&}+1$\,.@^\[[[A]]+{|}*]+}/{.{L%}{%$..&1$,1$,/*$=}:C~\{L/}C&},,
```
The input must be given on STDIN.
Examples:
```
11
01
-
0
111
111
-
1
100
001
001
-
2
11100
10101
11100
-
1
101
010
101
-
5
```
] |
Subsets and Splits