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http://rosettacode.org/wiki/Undefined_values | Undefined values | #Lingo | Lingo | put var
-- <Void>
put var=VOID
-- 1
put voidP(var)
-- 1
var = 23
put voidP(var)
-- 0 |
|
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Logo | Logo | ; procedures
to square :x
output :x * :x
end
show defined? "x ; true
show procedure? "x ; true (also works for built-in primitives)
erase "x
show defined? "x ; false
show square 3 ; I don't know how to square
; names
make "n 23
show name? "n ; true
ern "n
show name? "n ; false
show :n ; n has no value |
|
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #C | C | #include <stdio.h>
#include <stdlib.h>
#include <locale.h>
/* wchar_t is the standard type for wide chars; what it is internally
* depends on the compiler.
*/
wchar_t poker[] = L"♥♦♣♠";
wchar_t four_two[] = L"\x56db\x5341\x4e8c";
int main() {
/* Set the locale to alert C's multibyte output routines */
if (!setlocale(LC_CTYPE, "")) {
fprintf(stderr, "Locale failure, check your env vars\n");
return 1;
}
#ifdef __STDC_ISO_10646__
/* C99 compilers should understand these */
printf("%lc\n", 0x2708); /* ✈ */
printf("%ls\n", poker); /* ♥♦♣♠ */
printf("%ls\n", four_two); /* 四十二 */
#else
/* oh well */
printf("airplane\n");
printf("club diamond club spade\n");
printf("for ty two\n");
#endif
return 0;
} |
http://rosettacode.org/wiki/Ultra_useful_primes | Ultra useful primes | An ultra-useful prime is a member of the sequence where each a(n) is the smallest positive integer k such that 2(2n) - k is prime.
k must always be an odd number since 2 to any power is always even.
Task
Find and show here, on this page, the first 10 elements of the sequence.
Stretch
Find and show the next several elements. (The numbers get really big really fast. Only nineteen elements have been identified as of this writing.)
See also
OEIS:A058220 - Ultra-useful primes: smallest k such that 2^(2^n) - k is prime
| #Raku | Raku | sub useful ($n) {
(|$n).map: {
my $p = 1 +< ( 1 +< $_ );
^$p .first: ($p - *).is-prime
}
}
put useful 1..10;
put useful 11..13; |
http://rosettacode.org/wiki/Ultra_useful_primes | Ultra useful primes | An ultra-useful prime is a member of the sequence where each a(n) is the smallest positive integer k such that 2(2n) - k is prime.
k must always be an odd number since 2 to any power is always even.
Task
Find and show here, on this page, the first 10 elements of the sequence.
Stretch
Find and show the next several elements. (The numbers get really big really fast. Only nineteen elements have been identified as of this writing.)
See also
OEIS:A058220 - Ultra-useful primes: smallest k such that 2^(2^n) - k is prime
| #Sidef | Sidef | say(" n k")
say("----------")
for n in (1..13) {
var t = 2**(2**n)
printf("%2d %d\n", n, {|k| t - k -> is_prob_prime }.first)
} |
http://rosettacode.org/wiki/Ultra_useful_primes | Ultra useful primes | An ultra-useful prime is a member of the sequence where each a(n) is the smallest positive integer k such that 2(2n) - k is prime.
k must always be an odd number since 2 to any power is always even.
Task
Find and show here, on this page, the first 10 elements of the sequence.
Stretch
Find and show the next several elements. (The numbers get really big really fast. Only nineteen elements have been identified as of this writing.)
See also
OEIS:A058220 - Ultra-useful primes: smallest k such that 2^(2^n) - k is prime
| #Wren | Wren | import "./big" for BigInt
import "./fmt" for Fmt
var one = BigInt.one
var two = BigInt.two
var a = Fn.new { |n|
var p = (BigInt.one << (1 << n)) - one
var k = 1
while (true) {
if (p.isProbablePrime(5)) return k
p = p - two
k = k + 2
}
}
System.print(" n k")
System.print("----------")
for (n in 1..10) Fmt.print("$2d $d", n, a.call(n)) |
http://rosettacode.org/wiki/Unprimeable_numbers | Unprimeable numbers | Definitions
As used here, all unprimeable numbers (positive integers) are always expressed in base ten.
───── Definition from OEIS ─────:
Unprimeable numbers are composite numbers that always remain composite when a single decimal digit of the number is changed.
───── Definition from Wiktionary (referenced from Adam Spencer's book) ─────:
(arithmetic) that cannot be turned into a prime number by changing just one of its digits to any other
digit. (sic)
Unprimeable numbers are also spelled: unprimable.
All one─ and two─digit numbers can be turned into primes by changing a single decimal digit.
Examples
190 isn't unprimeable, because by changing the zero digit into a three yields 193, which is a prime.
The number 200 is unprimeable, since none of the numbers 201, 202, 203, ··· 209 are
prime, and all the other numbers obtained by changing a single digit to
produce 100, 300, 400, ··· 900, or 210, 220, 230, ··· 290 which are all even.
It is valid to change 189 into 089 by changing the 1 (one) into
a 0 (zero), which then the leading zero can be removed, and then treated as if
the "new" number is 89.
Task
show the first 35 unprimeable numbers (horizontally, on one line, preferably with a title)
show the 600th unprimeable number
(optional) show the lowest unprimeable number ending in a specific decimal digit (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
(optional) use commas in the numbers where appropriate
Show all output here, on this page.
Also see
the OEIS entry: A118118 (unprimeable)
with some useful counts to compare unprimeable number
the Wiktionary entry (reference from below): (arithmetic definition) unprimeable
from the Adam Spencer book (page 200): Adam Spencer's World of Numbers (Xoum Publishing)
| #Delphi | Delphi |
// Unprimeable numbers. Nigel Galloway: May 4th., 2021
let rec fN i g e l=seq{yield! [0..9]|>Seq.map(fun n->n*g+e+l); if g>1 then let g=g/10 in yield! fN(i+g*(e/g)) g (e%g) i}
let fG(n,g)=fN(n*(g/n)) n (g%n) 0|>Seq.exists(isPrime)
let uP()=let rec fN n g=seq{yield! {n..g-1}|>Seq.map(fun g->(n,g)); yield! fN(g)(g*10)} in fN 1 10|>Seq.filter(fG>>not)|>Seq.map snd
|
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Factor | Factor | USE: locals
[let
1 :> Δ!
Δ 1 + Δ!
Δ .
] |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Forth | Forth | variable ∆
1 ∆ !
1 ∆ +!
∆ @ . |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #FreeBASIC | FreeBASIC | 'FB 1.05.0 Win64
Var delta = 1
delta += 1
Print delta '' 2
Sleep |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #C.23 | C# | using System;
namespace Unbias
{
internal class Program
{
private static void Main(string[] args)
{
// Demonstrate.
for (int n = 3; n <= 6; n++)
{
int biasedZero = 0, biasedOne = 0, unbiasedZero = 0, unbiasedOne = 0;
for (int i = 0; i < 100000; i++)
{
if (randN(n))
biasedOne++;
else
biasedZero++;
if (Unbiased(n))
unbiasedOne++;
else
unbiasedZero++;
}
Console.WriteLine("(N = {0}):".PadRight(17) + "# of 0\t# of 1\t% of 0\t% of 1", n);
Console.WriteLine("Biased:".PadRight(15) + "{0}\t{1}\t{2}\t{3}",
biasedZero, biasedOne,
biasedZero/1000, biasedOne/1000);
Console.WriteLine("Unbiased:".PadRight(15) + "{0}\t{1}\t{2}\t{3}",
unbiasedZero, unbiasedOne,
unbiasedZero/1000, unbiasedOne/1000);
}
}
private static bool Unbiased(int n)
{
bool flip1, flip2;
/* Flip twice, and check if the values are the same.
* If so, flip again. Otherwise, return the value of the first flip. */
do
{
flip1 = randN(n);
flip2 = randN(n);
} while (flip1 == flip2);
return flip1;
}
private static readonly Random random = new Random();
private static bool randN(int n)
{
// Has an 1/n chance of returning 1. Otherwise it returns 0.
return random.Next(0, n) == 0;
}
}
} |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
An untouchable are those numbers that are not in the image of the aliquot sum function. (From Wikipedia)
Untouchable numbers: impossible values for the sum of all aliquot parts function. (From OEIS: The On-line Encyclopedia of Integer Sequences®)
An untouchable number is a positive integer that is not the sum of the proper divisors of any number. (From MathWorld™)
Observations and conjectures
All untouchable numbers > 5 are composite numbers.
No untouchable number is perfect.
No untouchable number is sociable.
No untouchable number is a Mersenne prime.
No untouchable number is one more than a prime number, since if p is prime, then
the sum of the proper divisors of p2 is p + 1.
No untouchable number is three more than an odd prime number, since if p is an odd prime, then the
sum of the proper divisors of 2p is p + 3.
The number 5 is believed to be the only odd untouchable number, but this has not been proven: it would follow from a
slightly stronger version of the Goldbach's conjecture, since the sum of the
proper divisors of pq (with p, q being
distinct primes) is 1 + p + q.
There are infinitely many untouchable numbers, a fact that was proven
by Paul Erdős.
According to Chen & Zhao, their natural density is at least d > 0.06.
Task
show (in a grid format) all untouchable numbers ≤ 2,000.
show (for the above) the count of untouchable numbers.
show the count of untouchable numbers from unity up to (inclusive):
10
100
1,000
10,000
100,000
... or as high as is you think is practical.
all output is to be shown here, on this page.
See also
Wolfram MathWorld: untouchable number.
OEIS: A005114 untouchable numbers.
OEIS: a list of all untouchable numbers below 100,000 (inclusive).
Wikipedia: untouchable number.
Wikipedia: Goldbach's conjecture.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | f = DivisorSigma[1, #] - # &;
limit = 10^5;
c = Not /@ PrimeQ[Range[limit]];
slimit = 15 limit;
s = ConstantArray[False, slimit + 1];
untouchable = {2, 5};
Do[
val = f[i];
If[val <= slimit,
s[[val]] = True
]
,
{i, 6, slimit}
]
Do[
If[! s[[n]],
If[c[[n - 1]],
If[c[[n - 3]],
AppendTo[untouchable, n]
]
]
]
,
{n, 6, limit, 2}
]
Multicolumn[Select[untouchable, LessEqualThan[2000]]]
Count[untouchable, _?(LessEqualThan[2000])]
Count[untouchable, _?(LessEqualThan[10])]
Count[untouchable, _?(LessEqualThan[100])]
Count[untouchable, _?(LessEqualThan[1000])]
Count[untouchable, _?(LessEqualThan[10000])]
Count[untouchable, _?(LessEqualThan[100000])] |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
An untouchable are those numbers that are not in the image of the aliquot sum function. (From Wikipedia)
Untouchable numbers: impossible values for the sum of all aliquot parts function. (From OEIS: The On-line Encyclopedia of Integer Sequences®)
An untouchable number is a positive integer that is not the sum of the proper divisors of any number. (From MathWorld™)
Observations and conjectures
All untouchable numbers > 5 are composite numbers.
No untouchable number is perfect.
No untouchable number is sociable.
No untouchable number is a Mersenne prime.
No untouchable number is one more than a prime number, since if p is prime, then
the sum of the proper divisors of p2 is p + 1.
No untouchable number is three more than an odd prime number, since if p is an odd prime, then the
sum of the proper divisors of 2p is p + 3.
The number 5 is believed to be the only odd untouchable number, but this has not been proven: it would follow from a
slightly stronger version of the Goldbach's conjecture, since the sum of the
proper divisors of pq (with p, q being
distinct primes) is 1 + p + q.
There are infinitely many untouchable numbers, a fact that was proven
by Paul Erdős.
According to Chen & Zhao, their natural density is at least d > 0.06.
Task
show (in a grid format) all untouchable numbers ≤ 2,000.
show (for the above) the count of untouchable numbers.
show the count of untouchable numbers from unity up to (inclusive):
10
100
1,000
10,000
100,000
... or as high as is you think is practical.
all output is to be shown here, on this page.
See also
Wolfram MathWorld: untouchable number.
OEIS: A005114 untouchable numbers.
OEIS: a list of all untouchable numbers below 100,000 (inclusive).
Wikipedia: untouchable number.
Wikipedia: Goldbach's conjecture.
| #Nim | Nim | import math, strutils
const
Lim1 = 100_000 # Limit for untouchable numbers.
Lim2 = 14 * Lim1 # Limit for computation of sum of divisors.
proc sumdiv(n: uint): uint =
## Return the sum of the strict divisors of "n".
result = 1
let r = sqrt(n.float).uint
let k = if (n and 1) == 0: 1u else: 2u
for d in countup(k + 1, r, k):
if n mod d == 0:
result += d
let q = n div d
if q != d: result += q
var
isSumDiv: array[1..Lim2, bool]
isPrime: array[1..Lim1, bool]
# Fill both sieves in a single pass.
for n in 1u..Lim2:
let s = sumdiv(n)
if s <= Lim2:
isSumDiv[s] = true
if s == 1 and n <= Lim1:
isPrime[n] = true
isPrime[1] = false
# Build list of untouchable numbers.
var list = @[2, 5]
for n in countup(6, Lim1, 2):
if not (isSumDiv[n] or isPrime[n - 1] or isPrime[n - 3]):
list.add n
echo "Untouchable numbers ≤ 2000:"
var count, lcount = 0
for n in list:
if n <= 2000:
stdout.write ($n).align(5)
inc count
inc lcount
if lcount == 20:
echo()
lcount = 0
else:
if lcount > 0: echo()
break
const CountMessage = "There are $1 untouchable numbers ≤ $2."
echo CountMessage.format(count, 2000), '\n'
count = 0
var lim = 10
for n in list:
if n > lim:
echo CountMessage.format(count, lim)
lim *= 10
inc count
if lim == Lim1:
# Emit last message.
echo CountMessage.format(count, lim) |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #FreeBASIC | FreeBASIC | #include "dir.bi"
Sub ls(Byref filespec As String, Byval attrib As Integer)
Dim As String filename = Dir(filespec, attrib)
Do While Len(filename) > 0
Print filename
filename = Dir()
Loop
End Sub
Dim As String directory = "" ' Current directory
ls(directory & "*", fbDirectory)
Sleep |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Frink | Frink | for f = sort[files["."], {|a,b| lexicalCompare[a.getName[], b.getName[]]}]
println[f.getName[]] |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #Racket | Racket |
#lang racket
(define (dot-product X Y)
(for/sum ([x (in-vector X)] [y (in-vector Y)]) (* x y)))
(define (cross-product X Y)
(define len (vector-length X))
(for/vector ([n len])
(define (ref V i) (vector-ref V (modulo (+ n i) len)))
(- (* (ref X 1) (ref Y 2)) (* (ref X 2) (ref Y 1)))))
(define (scalar-triple-product X Y Z)
(dot-product X (cross-product Y Z)))
(define (vector-triple-product X Y Z)
(cross-product X (cross-product Y Z)))
(define A '#(3 4 5))
(define B '#(4 3 5))
(define C '#(-5 -12 -13))
(printf "A = ~s\n" A)
(printf "B = ~s\n" B)
(printf "C = ~s\n" C)
(newline)
(printf "A . B = ~s\n" (dot-product A B))
(printf "A x B = ~s\n" (cross-product A B))
(printf "A . B x C = ~s\n" (scalar-triple-product A B C))
(printf "A x B x C = ~s\n" (vector-triple-product A B C))
|
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #TI-89_BASIC | TI-89 BASIC | Prgm
InputStr "Enter a string", s
Loop
Prompt integer
If integer ≠ 75000 Then
Disp "That wasn't 75000."
Else
Exit
EndIf
EndLoop
EndPrgm |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Toka | Toka | needs readline
." Enter a string: " readline is-data the-string
." Enter a number: " readline >number [ ." Not a number!" drop 0 ] ifFalse is-data the-number
the-string type cr
the-number . cr |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #LOLCODE | LOLCODE | HAI 1.3
I HAS A foo BTW, INISHULIZD TO NOOB
DIFFRINT foo AN FAIL, O RLY?
YA RLY, VISIBLE "FAIL != NOOB"
OIC
I HAS A bar ITZ 42
bar, O RLY?
YA RLY, VISIBLE "bar IZ DEFIND"
OIC
bar R NOOB BTW, UNDEF bar
bar, O RLY?
YA RLY, VISIBLE "SHUD NEVAR C DIS"
OIC
KTHXBYE |
|
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Lua | Lua | print( a )
local b
print( b )
if b == nil then
b = 5
end
print( b ) |
|
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #C.23 | C# |
(defvar ♥♦♣♠ "♥♦♣♠")
(defun ✈ () "a plane unicode function")
|
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #Common_Lisp | Common Lisp |
(defvar ♥♦♣♠ "♥♦♣♠")
(defun ✈ () "a plane unicode function")
|
http://rosettacode.org/wiki/Unprimeable_numbers | Unprimeable numbers | Definitions
As used here, all unprimeable numbers (positive integers) are always expressed in base ten.
───── Definition from OEIS ─────:
Unprimeable numbers are composite numbers that always remain composite when a single decimal digit of the number is changed.
───── Definition from Wiktionary (referenced from Adam Spencer's book) ─────:
(arithmetic) that cannot be turned into a prime number by changing just one of its digits to any other
digit. (sic)
Unprimeable numbers are also spelled: unprimable.
All one─ and two─digit numbers can be turned into primes by changing a single decimal digit.
Examples
190 isn't unprimeable, because by changing the zero digit into a three yields 193, which is a prime.
The number 200 is unprimeable, since none of the numbers 201, 202, 203, ··· 209 are
prime, and all the other numbers obtained by changing a single digit to
produce 100, 300, 400, ··· 900, or 210, 220, 230, ··· 290 which are all even.
It is valid to change 189 into 089 by changing the 1 (one) into
a 0 (zero), which then the leading zero can be removed, and then treated as if
the "new" number is 89.
Task
show the first 35 unprimeable numbers (horizontally, on one line, preferably with a title)
show the 600th unprimeable number
(optional) show the lowest unprimeable number ending in a specific decimal digit (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
(optional) use commas in the numbers where appropriate
Show all output here, on this page.
Also see
the OEIS entry: A118118 (unprimeable)
with some useful counts to compare unprimeable number
the Wiktionary entry (reference from below): (arithmetic definition) unprimeable
from the Adam Spencer book (page 200): Adam Spencer's World of Numbers (Xoum Publishing)
| #F.23 | F# |
// Unprimeable numbers. Nigel Galloway: May 4th., 2021
let rec fN i g e l=seq{yield! [0..9]|>Seq.map(fun n->n*g+e+l); if g>1 then let g=g/10 in yield! fN(i+g*(e/g)) g (e%g) i}
let fG(n,g)=fN(n*(g/n)) n (g%n) 0|>Seq.exists(isPrime)
let uP()=let rec fN n g=seq{yield! {n..g-1}|>Seq.map(fun g->(n,g)); yield! fN(g)(g*10)} in fN 1 10|>Seq.filter(fG>>not)|>Seq.map snd
|
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Frink | Frink |
Δ = 1
Δ = Δ + 1
println[Δ]
|
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Go | Go | package main
import "fmt"
func main() {
Δ := 1
Δ++
fmt.Println(Δ)
} |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Groovy | Groovy | main = print ψ
where δΔ = 1
ψ = δΔ + 1 |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #Clojure | Clojure | (defn biased [n]
(if (< (rand 2) (/ n)) 0 1))
(defn unbiased [n]
(loop [a 0 b 0]
(if (= a b)
(recur (biased n) (biased n))
a)))
(for [n (range 3 7)]
[n
(double (/ (apply + (take 50000 (repeatedly #(biased n)))) 50000))
(double (/ (apply + (take 50000 (repeatedly #(unbiased n)))) 50000))])
([3 0.83292 0.50422]
[4 0.87684 0.5023]
[5 0.90122 0.49728]
[6 0.91526 0.5]) |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
An untouchable are those numbers that are not in the image of the aliquot sum function. (From Wikipedia)
Untouchable numbers: impossible values for the sum of all aliquot parts function. (From OEIS: The On-line Encyclopedia of Integer Sequences®)
An untouchable number is a positive integer that is not the sum of the proper divisors of any number. (From MathWorld™)
Observations and conjectures
All untouchable numbers > 5 are composite numbers.
No untouchable number is perfect.
No untouchable number is sociable.
No untouchable number is a Mersenne prime.
No untouchable number is one more than a prime number, since if p is prime, then
the sum of the proper divisors of p2 is p + 1.
No untouchable number is three more than an odd prime number, since if p is an odd prime, then the
sum of the proper divisors of 2p is p + 3.
The number 5 is believed to be the only odd untouchable number, but this has not been proven: it would follow from a
slightly stronger version of the Goldbach's conjecture, since the sum of the
proper divisors of pq (with p, q being
distinct primes) is 1 + p + q.
There are infinitely many untouchable numbers, a fact that was proven
by Paul Erdős.
According to Chen & Zhao, their natural density is at least d > 0.06.
Task
show (in a grid format) all untouchable numbers ≤ 2,000.
show (for the above) the count of untouchable numbers.
show the count of untouchable numbers from unity up to (inclusive):
10
100
1,000
10,000
100,000
... or as high as is you think is practical.
all output is to be shown here, on this page.
See also
Wolfram MathWorld: untouchable number.
OEIS: A005114 untouchable numbers.
OEIS: a list of all untouchable numbers below 100,000 (inclusive).
Wikipedia: untouchable number.
Wikipedia: Goldbach's conjecture.
| #Pascal | Pascal | program UntouchableNumbers;
program UntouchableNumbers;
{$IFDEF FPC}
{$MODE DELPHI} {$OPTIMIZATION ON,ALL} {$COPERATORS ON}
{$CODEALIGN proc=16,loop=4}
{$ELSE}
{$APPTYPE CONSOLE}
{$ENDIF}
uses
sysutils,strutils
{$IFDEF WINDOWS},Windows{$ENDIF}
;
const
MAXPRIME = 1742537;
//sqr(MaxPrime) = 3e12
LIMIT = 5*1000*1000;
LIMIT_mul = trunc(exp(ln(LIMIT)/3))+1;
const
SizePrDeFe = 16*8192;//*size of(tprimeFac) =16 byte 2 Mb ~ level 3 cache
type
tdigits = array [0..31] of Uint32;
tprimeFac = packed record
pfSumOfDivs,
pfRemain : Uint64;
end;
tpPrimeFac = ^tprimeFac;
tPrimeDecompField = array[0..SizePrDeFe-1] of tprimeFac;
tPrimes = array[0..1 shl 17-1] of Uint32;
var
{$ALIGN 16}
PrimeDecompField :tPrimeDecompField;
{$ALIGN 16}
SmallPrimes: tPrimes;
pdfIDX,pdfOfs: NativeInt;
TD : Int64;
procedure OutCounts(pUntouch:pByte);
var
n,cnt,lim,deltaLim : NativeInt;
Begin
n := 0;
cnt := 0;
deltaLim := 100;
lim := deltaLim;
repeat
cnt += 1-pUntouch[n];
if n = lim then
Begin
writeln(Numb2USA(IntToStr(lim)):13,' ',Numb2USA(IntToStr(cnt)):12);
lim += deltaLim;
if lim = 10*deltaLim then
begin
deltaLim *=10;
lim := deltaLim;
writeln;
end;
end;
inc(n);
until n > LIMIT;
end;
function OutN(n:UInt64):UInt64;
begin
write(Numb2USA(IntToStr(n)):15,' dt ',(GettickCount64-TD)/1000:5:3,' s'#13);
TD := GettickCount64;
result := n+LIMIT;
end;
//######################################################################
//gets sum of divisors of consecutive integers fast
procedure InitSmallPrimes;
//get primes. Sieving only odd numbers
var
pr : array[0..MAXPRIME] of byte;
p,j,d,flipflop :NativeUInt;
Begin
SmallPrimes[0] := 2;
fillchar(pr[0],SizeOf(pr),#0);
p := 0;
repeat
repeat
p +=1
until pr[p]= 0;
j := (p+1)*p*2;
if j>MAXPRIME then
BREAK;
d := 2*p+1;
repeat
pr[j] := 1;
j += d;
until j>MAXPRIME;
until false;
SmallPrimes[1] := 3;
SmallPrimes[2] := 5;
j := 3;
flipflop := (2+1)-1;//7+2*2->11+2*1->13 ,17 ,19 , 23
p := 3;
repeat
if pr[p] = 0 then
begin
SmallPrimes[j] := 2*p+1;
inc(j);
end;
p+=flipflop;
flipflop := 3-flipflop;
until (p > MAXPRIME) OR (j>High(SmallPrimes));
end;
function CnvtoBASE(var dgt:tDigits;n:Uint64;base:NativeUint):NativeInt;
//n must be multiple of base aka n mod base must be 0
var
q,r: Uint64;
i : NativeInt;
Begin
fillchar(dgt,SizeOf(dgt),#0);
i := 0;
n := n div base;
result := 0;
repeat
r := n;
q := n div base;
r -= q*base;
n := q;
dgt[i] := r;
inc(i);
until (q = 0);
//searching lowest pot in base
result := 0;
while (result<i) AND (dgt[result] = 0) do
inc(result);
inc(result);
end;
function IncByOneInBase(var dgt:tDigits;base:NativeInt):NativeInt;
var
q :NativeInt;
Begin
result := 0;
q := dgt[result]+1;
if q = base then
repeat
dgt[result] := 0;
inc(result);
q := dgt[result]+1;
until q <> base;
dgt[result] := q;
result +=1;
end;
procedure CalcSumOfDivs(var pdf:tPrimeDecompField;var dgt:tDigits;n,k,pr:Uint64);
var
fac,s :Uint64;
j : Int32;
Begin
//j is power of prime
j := CnvtoBASE(dgt,n+k,pr);
repeat
fac := 1;
s := 1;
repeat
fac *= pr;
dec(j);
s += fac;
until j<= 0;
with pdf[k] do
Begin
pfSumOfDivs *= s;
pfRemain := pfRemain DIV fac;
end;
j := IncByOneInBase(dgt,pr);
k += pr;
until k >= SizePrDeFe;
end;
function SieveOneSieve(var pdf:tPrimeDecompField):boolean;
var
dgt:tDigits;
i,j,k,pr,n,MaxP : Uint64;
begin
n := pdfOfs;
if n+SizePrDeFe >= sqr(SmallPrimes[High(SmallPrimes)]) then
EXIT(FALSE);
//init
for i := 0 to SizePrDeFe-1 do
begin
with pdf[i] do
Begin
pfSumOfDivs := 1;
pfRemain := n+i;
end;
end;
//first factor 2. Make n+i even
i := (pdfIdx+n) AND 1;
IF (n = 0) AND (pdfIdx<2) then
i := 2;
repeat
with pdf[i] do
begin
j := BsfQWord(n+i);
pfRemain := (n+i) shr j;
pfSumOfDivs := (Uint64(1) shl (j+1))-1;
end;
i += 2;
until i >=SizePrDeFe;
//i now index in SmallPrimes
i := 0;
maxP := trunc(sqrt(n+SizePrDeFe))+1;
repeat
//search next prime that is in bounds of sieve
if n = 0 then
begin
repeat
inc(i);
pr := SmallPrimes[i];
k := pr-n MOD pr;
if k < SizePrDeFe then
break;
until pr > MaxP;
end
else
begin
repeat
inc(i);
pr := SmallPrimes[i];
k := pr-n MOD pr;
if (k = pr) AND (n>0) then
k:= 0;
if k < SizePrDeFe then
break;
until pr > MaxP;
end;
//no need to use higher primes
if pr > maxP then
BREAK;
CalcSumOfDivs(pdf,dgt,n,k,pr);
until false;
//correct sum of & count of divisors
for i := 0 to High(pdf) do
Begin
with pdf[i] do
begin
j := pfRemain;
if j <> 1 then
pfSumOFDivs *= (j+1);
end;
end;
result := true;
end;
function NextSieve:boolean;
begin
dec(pdfIDX,SizePrDeFe);
inc(pdfOfs,SizePrDeFe);
result := SieveOneSieve(PrimeDecompField);
end;
function GetNextPrimeDecomp:tpPrimeFac;
begin
if pdfIDX >= SizePrDeFe then
if Not(NextSieve) then
Begin
writeln('of limits ');
EXIT(NIL);
end;
result := @PrimeDecompField[pdfIDX];
inc(pdfIDX);
end;
function Init_Sieve(n:NativeUint):boolean;
//Init Sieve pdfIdx,pdfOfs are Global
begin
pdfIdx := n MOD SizePrDeFe;
pdfOfs := n-pdfIdx;
result := SieveOneSieve(PrimeDecompField);
end;
//gets sum of divisors of consecutive integers fast
//######################################################################
procedure CheckRest(n: Uint64;pUntouch:pByte);
var
k,lim : Uint64;
begin
lim := 2*LIMIT;
repeat
k := GetNextPrimeDecomp^.pfSumOfDivs-n;
inc(n);
if Not(ODD(k)) AND (k<=LIMIT) then
pUntouch[k] := 1;
// showing still alive not for TIO.RUN
// if n >= lim then lim := OutN(n);
until n >LIMIT_mul*LIMIT;
end;
var
Untouch : array of byte;
pUntouch: pByte;
puQW : pQword;
T0:Int64;
n,k : NativeInt;
Begin
if sqrt(LIMIT_mul*LIMIT) >=MAXPRIME then
Begin
writeln('Need to extend count of primes > ',
trunc(sqrt(LIMIT_mul*LIMIT))+1);
HALT(0);
end;
setlength(untouch,LIMIT+8+1);
pUntouch := @untouch[0];
//Mark all odd as touchable
puQW := @pUntouch[0];
For n := 0 to LIMIT DIV 8 do puQW[n] := $0100010001000100;
InitSmallPrimes;
T0 := GetTickCount64;
writeln('LIMIT = ',Numb2USA(IntToStr(LIMIT)));
writeln('factor beyond LIMIT ',LIMIT_mul);
n := 0;
Init_Sieve(n);
pUntouch[1] := 1;//all primes
repeat
k := GetNextPrimeDecomp^.pfSumOfDivs-n;
inc(n);//n-> n+1
if k <= LIMIT then
begin
If k <> 1 then
pUntouch[k] := 1
else
begin
//n-1 is prime p
//mark p*p
pUntouch[n] := 1;
//mark 2*p
//5 marked by prime 2 but that is p*p, but 4 has factor sum = 3
pUntouch[n+2] := 1;
end;
end;
until n > LIMIT-2;
//unmark 5 and mark 0
puntouch[5] := 0;
pUntouch[0] := 1;
//n=limit-1
k := GetNextPrimeDecomp^.pfSumOfDivs-n;
inc(n);
If (k <> 1) AND (k<=LIMIT) then
pUntouch[k] := 1
else
pUntouch[n] := 1;
//n=limit
k := GetNextPrimeDecomp^.pfSumOfDivs-n;
If Not(odd(k)) AND (k<=LIMIT) then
pUntouch[k] := 1;
n:= limit+1;
writeln('runtime for n<= LIMIT ',(GetTickCount64-T0)/1000:0:3,' s');
writeln('Check the rest ',Numb2USA(IntToStr((LIMIT_mul-1)*Limit)));
TD := GettickCount64;
CheckRest(n,pUntouch);
writeln('runtime ',(GetTickCount64-T0)/1000:0:3,' s');
T0 := GetTickCount64-T0;
OutCounts(pUntouch);
end. |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #FunL | FunL | import io.File
for f <- sort( list(File( "." ).list()).filterNot(s -> s.startsWith(".")) )
println( f ) |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Furor | Furor |
###sysinclude dir.uh
###sysinclude stringextra.uh
###define COLORS
// delete the COLORS directive above if you do not want colored output!
{ „vonal” __usebigbossnamespace myself "-" 90 makestring() }
{ „points” __usebigbossnamespace myself "." 60 makestring() }
#g argc 3 < { "." }{ 2 argv } sto mypath
@mypath 'd !istrue { ."The give directory doesn't exist! Exited.\n" end }
@mypath getdir { ."Cannot load the dir! Aborted.\n" end } sto mydir
@mydir ~d {
."Directories:\n"
@mydir ~d {| #s
@mydir 'd {} octalrights dup print free SPACE
@mydir 'd {} getfilename dup 37 stub print SPACE drop
@mydir 'd {} groupname ': !+
@mydir 'd {} ownername dup sto temp + dup 10 stub print free @temp free
@mydir 'd {} mtime dup print free
NL |}
@points sprint
@mydir ~d { ."Total: " @mydir ~d #g print ." subdirectories.\n" }
@vonal sprint
}
@mydir ~r {
."Regular files:\n"
@mydir ~r {| #s
@mydir 'r {} octalrights dup print free SPACE
@mydir 'r {} getfilesize sbr §ifcolored
@mydir 'r {} executable { ." >" }{ ." " } SPACE
@mydir 'r {} getfilename dup 37 stub print SPACE drop
@mydir 'r {} groupname ': !+
@mydir 'r {} ownername dup sto temp + dup 10 stub print free @temp free
@mydir 'r {} mtime dup print free
NL |}
@points sprint
@mydir ~r { ."Total: " @mydir ~r #g print ." regular files. "
."TotalSize = " @mydir 'r totalsize sbr §ifcolored NL
}
@vonal sprint
}
@mydir ~L {
."Symlinks:\n"
@mydir ~L {| #s
@mydir 'L {} octalrights dup print free SPACE
@mydir 'L {} executable { .">" }{ SPACE } SPACE
@mydir 'L {} getfilename dup 67 stub print SPACE drop
@mydir 'L {} broken { ."--->" }{ ."===>" } SPACE
@mydir 'L {} destination dup 30 stub print drop
NL |}
@points sprint
@mydir ~L { ."Total: " @mydir ~L #g print ." symlinks.\n"
}
}
@vonal sprint
."Size, alltogether = " @mydir alltotal sbr §ifcolored NL
@vonal sprint
@mydir free
."Free spaces: /* Total size of the filesystem is : " @mypath filesystemsize dup sto filsize sbr §ifcolored ." */\n"
." for non-privilegized use: " @mypath freenonpriv dup sbr §ifcolored
#g 100 * @filsize / ." ( " print ."% ) " NL
." All available free space: " @mypath totalfree dup sbr §ifcolored
#g 100 * @filsize / ." ( " print ."% ) " NL
end
ifcolored:
###ifdef COLORS
coloredsize
###endif
###ifndef COLORS
#g !(#s) 21 >|
###endif
dup sprint free
rts
{ „filsize” }
{ „mydir” }
{ „mypath” }
{ „temp” }
{ „makestring” #s * dup 10 !+ swap free #g = }
|
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #Raku | Raku | sub infix:<⋅> { [+] @^a »*« @^b }
sub infix:<⨯>([$a1, $a2, $a3], [$b1, $b2, $b3]) {
[ $a2*$b3 - $a3*$b2,
$a3*$b1 - $a1*$b3,
$a1*$b2 - $a2*$b1 ];
}
sub scalar-triple-product { @^a ⋅ (@^b ⨯ @^c) }
sub vector-triple-product { @^a ⨯ (@^b ⨯ @^c) }
my @a = <3 4 5>;
my @b = <4 3 5>;
my @c = <-5 -12 -13>;
say (:@a, :@b, :@c);
say "a ⋅ b = { @a ⋅ @b }";
say "a ⨯ b = <{ @a ⨯ @b }>";
say "a ⋅ (b ⨯ c) = { scalar-triple-product(@a, @b, @c) }";
say "a ⨯ (b ⨯ c) = <{ vector-triple-product(@a, @b, @c) }>"; |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #TUSCRIPT | TUSCRIPT |
$$ MODE TUSCRIPT
LOOP
ASK "Enter a string": str=""
ASK "Enter an integer": int=""
IF (int=='digits') THEN
PRINT "int=",int," str=",str
EXIT
ELSE
PRINT/ERROR int," is not an integer"
CYCLE
ENDIF
ENDLOOP
|
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #UNIX_Shell | UNIX Shell | #!/bin/sh
read string
read integer
read -p 'Enter a number: ' number
echo "The number is $number" |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | a
-> a
a + a
-> 2 a
ValueQ[a]
-> False
a = 5
-> 5
ValueQ[a]
-> True |
|
http://rosettacode.org/wiki/Undefined_values | Undefined values | #MATLAB_.2F_Octave | MATLAB / Octave | global var; |
|
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #D | D | import std.stdio;
import std.uni; // standard package for normalization, composition/decomposition, etc..
import std.utf; // standard package for decoding/encoding, etc...
void main() {
// normal identifiers are allowed
int a;
// unicode characters are allowed for identifers
int δ;
char c; // 1 to 4 byte unicode character
wchar w; // 2 or 4 byte unicode character
dchar d; // 4 byte unicode character
writeln("some text"); // strings by default are UTF8
writeln("some text"c); // optional suffix for UTF8
writeln("こんにちは"c); // unicode charcters are just fine (stored in the string type)
writeln("Здравствуйте"w); // also avaiable are UTF16 string (stored in the wstring type)
writeln("שלום"d); // and UTF32 strings (stored in the dstring type)
// escape sequences like what is defined in C are also allowed inside of strings and characters.
} |
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #DWScript | DWScript | public program()
{
var 四十二 := "♥♦♣♠"; // UTF8 string
var строка := "Привет"w; // UTF16 string
console.writeLine:строка;
console.writeLine:四十二;
} |
http://rosettacode.org/wiki/Unprimeable_numbers | Unprimeable numbers | Definitions
As used here, all unprimeable numbers (positive integers) are always expressed in base ten.
───── Definition from OEIS ─────:
Unprimeable numbers are composite numbers that always remain composite when a single decimal digit of the number is changed.
───── Definition from Wiktionary (referenced from Adam Spencer's book) ─────:
(arithmetic) that cannot be turned into a prime number by changing just one of its digits to any other
digit. (sic)
Unprimeable numbers are also spelled: unprimable.
All one─ and two─digit numbers can be turned into primes by changing a single decimal digit.
Examples
190 isn't unprimeable, because by changing the zero digit into a three yields 193, which is a prime.
The number 200 is unprimeable, since none of the numbers 201, 202, 203, ··· 209 are
prime, and all the other numbers obtained by changing a single digit to
produce 100, 300, 400, ··· 900, or 210, 220, 230, ··· 290 which are all even.
It is valid to change 189 into 089 by changing the 1 (one) into
a 0 (zero), which then the leading zero can be removed, and then treated as if
the "new" number is 89.
Task
show the first 35 unprimeable numbers (horizontally, on one line, preferably with a title)
show the 600th unprimeable number
(optional) show the lowest unprimeable number ending in a specific decimal digit (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
(optional) use commas in the numbers where appropriate
Show all output here, on this page.
Also see
the OEIS entry: A118118 (unprimeable)
with some useful counts to compare unprimeable number
the Wiktionary entry (reference from below): (arithmetic definition) unprimeable
from the Adam Spencer book (page 200): Adam Spencer's World of Numbers (Xoum Publishing)
| #Factor | Factor | USING: assocs formatting io kernel lists lists.lazy
lists.lazy.examples math math.functions math.primes math.ranges
math.text.utils prettyprint sequences tools.memory.private ;
: one-offs ( n -- seq )
dup 1 digit-groups [
swapd 10^ [ * ] keep [ - ] dip
2dup [ 9 * ] [ + ] [ <range> ] tri*
] with map-index concat ;
: (unprimeable?) ( n -- ? )
[ f ] [ one-offs [ prime? ] none? ] if-zero ;
: unprimeable? ( n -- ? )
dup prime? [ drop f ] [ (unprimeable?) ] if ;
: unprimeables ( -- list ) naturals [ unprimeable? ] lfilter ;
: ?set-at ( value key assoc -- )
2dup key? [ 3drop ] [ set-at ] if ;
: first-digits ( -- assoc )
unprimeables H{ } clone [ dup assoc-size 10 = ]
[ [ unswons dup 10 mod ] dip [ ?set-at ] keep ] until nip ;
"The first 35 unprimeable numbers:" print bl bl
35 unprimeables ltake [ pprint bl ] leach nl nl
"The 600th unprimeable number:" print bl bl
599 unprimeables lnth commas print nl
"The first unprimeable number ending with" print
first-digits [ commas " %d: %9s\n" printf ] assoc-each |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Haskell | Haskell | main = print ψ
where δΔ = 1
ψ = δΔ + 1 |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #J | J | int Δ = 1;
double π = 3.141592;
String 你好 = "hello";
Δ++;
System.out.println(Δ); |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #CoffeeScript | CoffeeScript |
biased_rand_function = (n) ->
# return a function that returns 0/1 with
# 1 appearing only 1/Nth of the time
cap = 1/n
->
if Math.random() < cap
1
else
0
unbiased_function = (f) ->
->
while true
[n1, n2] = [f(), f()]
return n1 if n1 + n2 == 1
stats = (label, f) ->
cnt = 0
sample_size = 10000000
for i in [1...sample_size]
cnt += 1 if f() == 1
console.log "ratio of 1s: #{cnt / sample_size} [#{label}]"
for n in [3..6]
console.log "\n---------- n = #{n}"
f_biased = biased_rand_function(n)
f_unbiased = unbiased_function f_biased
stats "biased", f_biased
stats "unbiased", f_unbiased
|
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #Common_Lisp | Common Lisp | (defun biased (n) (if (zerop (random n)) 0 1))
(defun unbiased (n)
(loop with x do
(if (/= (setf x (biased n)) (biased n))
(return x))))
(loop for n from 3 to 6 do
(let ((u (loop repeat 10000 collect (unbiased n)))
(b (loop repeat 10000 collect (biased n))))
(format t "~a: unbiased ~d biased ~d~%" n (count 0 u) (count 0 b)))) |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
An untouchable are those numbers that are not in the image of the aliquot sum function. (From Wikipedia)
Untouchable numbers: impossible values for the sum of all aliquot parts function. (From OEIS: The On-line Encyclopedia of Integer Sequences®)
An untouchable number is a positive integer that is not the sum of the proper divisors of any number. (From MathWorld™)
Observations and conjectures
All untouchable numbers > 5 are composite numbers.
No untouchable number is perfect.
No untouchable number is sociable.
No untouchable number is a Mersenne prime.
No untouchable number is one more than a prime number, since if p is prime, then
the sum of the proper divisors of p2 is p + 1.
No untouchable number is three more than an odd prime number, since if p is an odd prime, then the
sum of the proper divisors of 2p is p + 3.
The number 5 is believed to be the only odd untouchable number, but this has not been proven: it would follow from a
slightly stronger version of the Goldbach's conjecture, since the sum of the
proper divisors of pq (with p, q being
distinct primes) is 1 + p + q.
There are infinitely many untouchable numbers, a fact that was proven
by Paul Erdős.
According to Chen & Zhao, their natural density is at least d > 0.06.
Task
show (in a grid format) all untouchable numbers ≤ 2,000.
show (for the above) the count of untouchable numbers.
show the count of untouchable numbers from unity up to (inclusive):
10
100
1,000
10,000
100,000
... or as high as is you think is practical.
all output is to be shown here, on this page.
See also
Wolfram MathWorld: untouchable number.
OEIS: A005114 untouchable numbers.
OEIS: a list of all untouchable numbers below 100,000 (inclusive).
Wikipedia: untouchable number.
Wikipedia: Goldbach's conjecture.
| #Perl | Perl | use strict;
use warnings;
use enum qw(False True);
use ntheory qw/divisor_sum is_prime/;
sub sieve {
my($n) = @_;
my %s;
for my $k (0 .. $n+1) {
my $sum = divisor_sum($k) - $k;
$s{$sum} = True if $sum <= $n+1;
}
%s
}
my(%s,%c);
my($max, $limit, $cnt) = (2000, 1e5, 0);
%s = sieve 14 * $limit;
!is_prime($_) and $c{$_} = True for 1..$limit;
my @untouchable = (2, 5);
for ( my $n = 6; $n <= $limit; $n += 2 ) {
push @untouchable, $n if !$s{$n} and $c{$n-1} and $c{$n-3};
}
map { $cnt++ if $_ <= $max } @untouchable;
print "Number of untouchable numbers ≤ $max : $cnt \n\n" .
(sprintf "@{['%6d' x $cnt]}", @untouchable[0..$cnt-1]) =~ s/(.{84})/$1\n/gr . "\n";
my($p, $count) = (10, 0);
my $fmt = "%6d untouchable numbers were found ≤ %7d\n";
for my $n (@untouchable) {
$count++;
if ($n > $p) {
printf $fmt, $count-1, $p;
printf($fmt, scalar @untouchable, $limit) and last if $limit == ($p *= 10)
}
} |
http://rosettacode.org/wiki/Ukkonen%E2%80%99s_suffix_tree_construction | Ukkonen’s suffix tree construction | Suffix Trees are very useful in numerous string processing and computational biology problems.
The task is to create a function which implements Ukkonen’s algorithm to create a useful Suffix Tree as described:
Part 1
Part 2
Part 3
Part 4
Part 5
Part 6
Using Arithmetic-geometric mean/Calculate Pi generate the first 1000, 10000, and 100000 decimal places of pi. Using your implementation with an alphabet of 0 through 9 (plus $ say to make the tree explicit) find the longest repeated string in each list. Time your results and demonstrate that your implementation is linear (i.e. that 10000 takes approx. 10 times as long as 1000). You may vary the size of the lists of decimal places of pi to give reasonable answers.
| #Go | Go | package main
import (
"fmt"
"math/big"
"time"
)
var maxChar = 128
type Node struct {
children []*Node
suffixLink *Node
start int
end *int
suffixIndex int
}
var (
text string
root *Node
lastNewNode *Node
activeNode *Node
activeEdge = -1
activeLength = 0
remainingSuffixCount = 0
leafEnd = -1
rootEnd *int
splitEnd *int
size = -1
)
func newNode(start int, end *int) *Node {
node := new(Node)
node.children = make([]*Node, maxChar)
node.suffixLink = root
node.start = start
node.end = end
node.suffixIndex = -1
return node
}
func edgeLength(n *Node) int {
if n == root {
return 0
}
return *(n.end) - n.start + 1
}
func walkDown(currNode *Node) bool {
if activeLength >= edgeLength(currNode) {
activeEdge += edgeLength(currNode)
activeLength -= edgeLength(currNode)
activeNode = currNode
return true
}
return false
}
func extendSuffixTree(pos int) {
leafEnd = pos
remainingSuffixCount++
lastNewNode = nil
for remainingSuffixCount > 0 {
if activeLength == 0 {
activeEdge = pos
}
if activeNode.children[text[activeEdge]] == nil {
activeNode.children[text[activeEdge]] = newNode(pos, &leafEnd)
if lastNewNode != nil {
lastNewNode.suffixLink = activeNode
lastNewNode = nil
}
} else {
next := activeNode.children[text[activeEdge]]
if walkDown(next) {
continue
}
if text[next.start+activeLength] == text[pos] {
if lastNewNode != nil && activeNode != root {
lastNewNode.suffixLink = activeNode
lastNewNode = nil
}
activeLength++
break
}
temp := next.start + activeLength - 1
splitEnd = &temp
split := newNode(next.start, splitEnd)
activeNode.children[text[activeEdge]] = split
split.children[text[pos]] = newNode(pos, &leafEnd)
next.start += activeLength
split.children[text[next.start]] = next
if lastNewNode != nil {
lastNewNode.suffixLink = split
}
lastNewNode = split
}
remainingSuffixCount--
if activeNode == root && activeLength > 0 {
activeLength--
activeEdge = pos - remainingSuffixCount + 1
} else if activeNode != root {
activeNode = activeNode.suffixLink
}
}
}
func setSuffixIndexByDFS(n *Node, labelHeight int) {
if n == nil {
return
}
if n.start != -1 {
// Uncomment line below to print suffix tree
// fmt.Print(text[n.start: *(n.end) +1])
}
leaf := 1
for i := 0; i < maxChar; i++ {
if n.children[i] != nil {
// Uncomment the 3 lines below to print suffix index
//if leaf == 1 && n.start != -1 {
// fmt.Printf(" [%d]\n", n.suffixIndex)
//}
leaf = 0
setSuffixIndexByDFS(n.children[i], labelHeight+edgeLength(n.children[i]))
}
}
if leaf == 1 {
n.suffixIndex = size - labelHeight
// Uncomment line below to print suffix index
//fmt.Printf(" [%d]\n", n.suffixIndex)
}
}
func buildSuffixTree() {
size = len(text)
temp := -1
rootEnd = &temp
root = newNode(-1, rootEnd)
activeNode = root
for i := 0; i < size; i++ {
extendSuffixTree(i)
}
labelHeight := 0
setSuffixIndexByDFS(root, labelHeight)
}
func doTraversal(n *Node, labelHeight int, maxHeight, substringStartIndex *int) {
if n == nil {
return
}
if n.suffixIndex == -1 {
for i := 0; i < maxChar; i++ {
if n.children[i] != nil {
doTraversal(n.children[i], labelHeight+edgeLength(n.children[i]),
maxHeight, substringStartIndex)
}
}
} else if n.suffixIndex > -1 && (*maxHeight < labelHeight-edgeLength(n)) {
*maxHeight = labelHeight - edgeLength(n)
*substringStartIndex = n.suffixIndex
}
}
func getLongestRepeatedSubstring(s string) {
maxHeight := 0
substringStartIndex := 0
doTraversal(root, 0, &maxHeight, &substringStartIndex)
// Uncomment line below to print maxHeight and substringStartIndex
// fmt.Printf("maxHeight %d, substringStartIndex %d\n", maxHeight, substringStartIndex)
if s == "" {
fmt.Printf(" %s is: ", text)
} else {
fmt.Printf(" %s is: ", s)
}
k := 0
for ; k < maxHeight; k++ {
fmt.Printf("%c", text[k+substringStartIndex])
}
if k == 0 {
fmt.Print("No repeated substring")
}
fmt.Println()
}
func calculatePi() *big.Float {
one := big.NewFloat(1)
two := big.NewFloat(2)
four := big.NewFloat(4)
prec := uint(325 * 1024) // enough to calculate Pi to 100,182 decimal digits
a := big.NewFloat(1).SetPrec(prec)
g := new(big.Float).SetPrec(prec)
// temporary variables
t := new(big.Float).SetPrec(prec)
u := new(big.Float).SetPrec(prec)
g.Quo(a, t.Sqrt(two))
sum := new(big.Float)
pow := big.NewFloat(2)
for a.Cmp(g) != 0 {
t.Add(a, g)
t.Quo(t, two)
g.Sqrt(u.Mul(a, g))
a.Set(t)
pow.Mul(pow, two)
t.Sub(t.Mul(a, a), u.Mul(g, g))
sum.Add(sum, t.Mul(t, pow))
}
t.Mul(a, a)
t.Mul(t, four)
pi := t.Quo(t, u.Sub(one, sum))
return pi
}
func main() {
tests := []string{
"GEEKSFORGEEKS$",
"AAAAAAAAAA$",
"ABCDEFG$",
"ABABABA$",
"ATCGATCGA$",
"banana$",
"abcpqrabpqpq$",
"pqrpqpqabab$",
}
fmt.Println("Longest Repeated Substring in:\n")
for _, test := range tests {
text = test
buildSuffixTree()
getLongestRepeatedSubstring("")
}
fmt.Println()
pi := calculatePi()
piStr := fmt.Sprintf("%v", pi)
piStr = piStr[2:] // remove initial 3.
numbers := []int{1e3, 1e4, 1e5}
maxChar = 58
for _, number := range numbers {
start := time.Now()
text = piStr[0:number] + "$"
buildSuffixTree()
getLongestRepeatedSubstring(fmt.Sprintf("first %d d.p. of Pi", number))
elapsed := time.Now().Sub(start)
fmt.Printf(" (this took %s)\n\n", elapsed)
}
} |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Gambas | Gambas | Public Sub Main()
Dim sDir As String[] = Dir(User.Home &/ "test").Sort()
Print sDir.Join(gb.NewLine)
End |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Go | Go | package main
import (
"fmt"
"log"
"os"
"sort"
)
func main() {
f, err := os.Open(".")
if err != nil {
log.Fatal(err)
}
files, err := f.Readdirnames(0)
f.Close()
if err != nil {
log.Fatal(err)
}
sort.Strings(files)
for _, n := range files {
fmt.Println(n)
}
} |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #REXX | REXX | /*REXX program computes the products: dot, cross, scalar triple, and vector triple.*/
a= 3 4 5
b= 4 3 5 /*(positive numbers don't need quotes.)*/
c= "-5 -12 -13"
call tellV 'vector A =', a /*show the A vector, aligned numbers.*/
call tellV 'vector B =', b /* " " B " " " */
call tellV 'vector C =', c /* " " C " " " */
say
call tellV ' dot product [A∙B] =', dot(a, b)
call tellV 'cross product [AxB] =', cross(a, b)
call tellV 'scalar triple product [A∙(BxC)] =', dot(a, cross(b, c) )
call tellV 'vector triple product [Ax(BxC)] =', cross(a, cross(b, c) )
exit 0 /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
cross: procedure; arg $1 $2 $3,@1 @2 @3; return $2*@3 -$3*@2 $3*@1 -$1*@3 $1*@2 -$2*@1
dot: procedure; arg $1 $2 $3,@1 @2 @3; return $1*@1 + $2*@2 + $3*@3
/*──────────────────────────────────────────────────────────────────────────────────────*/
tellV: procedure; parse arg name,x y z; w=max(4,length(x),length(y),length(z)) /*max W*/
say right(name,40) right(x,w) right(y,w) right(z,w); /*show vector.*/ return |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Ursa | Ursa | #
# user input
#
# in ursa, the type of data expected must be specified
decl string str
decl int i
out "input a string: " console
set str (in string console)
out "input an int: " console
set i (in int console)
out "you entered " str " and " i endl console |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #VBA | VBA | Public Sub text()
Debug.Print InputBox("Input a string")
Debug.Print InputBox("Input the integer 75000", "Input an integer", 75000, Context = "Long")
End Sub |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #MUMPS | MUMPS | IF $DATA(SOMEVAR)=0 DO UNDEF ; A result of 0 means the value is undefined
SET LOCAL=$GET(^PATIENT(RECORDNUM,0)) ;If there isn't a defined item at that location, a null string is returned |
|
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Nim | Nim | var a {.noInit.}: array[1_000_000, int]
# For a proc, {.noInit.} means that the result is not initialized.
proc p(): array[1000, int] {.noInit.} =
for i in 0..999: result[i] = i |
|
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #Elena | Elena | public program()
{
var 四十二 := "♥♦♣♠"; // UTF8 string
var строка := "Привет"w; // UTF16 string
console.writeLine:строка;
console.writeLine:四十二;
} |
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #Elixir | Elixir | var i int
var u rune
for i, u = range "voilà" {
fmt.Println(i, u)
} |
http://rosettacode.org/wiki/Unprimeable_numbers | Unprimeable numbers | Definitions
As used here, all unprimeable numbers (positive integers) are always expressed in base ten.
───── Definition from OEIS ─────:
Unprimeable numbers are composite numbers that always remain composite when a single decimal digit of the number is changed.
───── Definition from Wiktionary (referenced from Adam Spencer's book) ─────:
(arithmetic) that cannot be turned into a prime number by changing just one of its digits to any other
digit. (sic)
Unprimeable numbers are also spelled: unprimable.
All one─ and two─digit numbers can be turned into primes by changing a single decimal digit.
Examples
190 isn't unprimeable, because by changing the zero digit into a three yields 193, which is a prime.
The number 200 is unprimeable, since none of the numbers 201, 202, 203, ··· 209 are
prime, and all the other numbers obtained by changing a single digit to
produce 100, 300, 400, ··· 900, or 210, 220, 230, ··· 290 which are all even.
It is valid to change 189 into 089 by changing the 1 (one) into
a 0 (zero), which then the leading zero can be removed, and then treated as if
the "new" number is 89.
Task
show the first 35 unprimeable numbers (horizontally, on one line, preferably with a title)
show the 600th unprimeable number
(optional) show the lowest unprimeable number ending in a specific decimal digit (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
(optional) use commas in the numbers where appropriate
Show all output here, on this page.
Also see
the OEIS entry: A118118 (unprimeable)
with some useful counts to compare unprimeable number
the Wiktionary entry (reference from below): (arithmetic definition) unprimeable
from the Adam Spencer book (page 200): Adam Spencer's World of Numbers (Xoum Publishing)
| #FreeBASIC | FreeBASIC |
Function isprime(n As Ulongint) As boolean
If (n=2) Or (n=3) Then Return 1
If n Mod 2 = 0 Then Return 0
If n Mod 3 = 0 Then Return 0
Dim As Ulongint limit=Sqr(N)+1
For I As Ulongint = 6 To limit Step 6
If N Mod (i-1) = 0 Then Return 0
If N Mod (i+1) = 0 Then Return 0
Next I
Return 1
End Function
Sub getnonprimeables(a() As Long)
Dim As String s,g
Dim As Long count,lim=1300000
Redim a(1 To lim)
For num As Long=1 To lim
g=Str(num)
s=g
For n As Long=0 To Len(s)-1
For m As Long=48 To 57
s[n]=m
If isprime(Vallng(s)) Then Goto lbl
Next m
s=g
Next n
count+=1
a(count)=num
lbl:
Next num
Redim Preserve a(1 To count)
End Sub
Function endings(n As String,a() As Long) As Long
For m As Long=1 To Ubound(a)
If Right(Str(a(m)),1)=n Then Return a(m)
Next m
End Function
Redim As Long n()
getnonprimeables(n())
print " First 35"
For m As Long=1 To 35
Print n(m);
Next
Print
Print "600th number ";n(600)
For z As Long=0 To 9
Print "first umprimable number ending in ";z; " is ";endings(Str(z),n())
Next z
sleep
|
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Java | Java | int Δ = 1;
double π = 3.141592;
String 你好 = "hello";
Δ++;
System.out.println(Δ); |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #JavaScript | JavaScript | var ᾩ = "something";
var ĦĔĽĻŎ = "hello";
var 〱〱〱〱 = "too less";
var जावास्क्रिप्ट = "javascript"; // ok that's JavaScript in hindi
var KingGeorgeⅦ = "Roman numerals.";
console.log([ᾩ, ĦĔĽĻŎ, 〱〱〱〱, जावास्क्रिप्ट, KingGeorgeⅦ]) |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #jq | jq | { "Δ": 1 } | .["Δ"] |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #D | D | import std.stdio, std.random, std.algorithm, std.range, std.functional;
enum biased = (in int n) /*nothrow*/ => uniform01 < (1.0 / n);
int unbiased(in int bias) /*nothrow*/ {
int a;
while ((a = bias.biased) == bias.biased) {}
return a;
}
void main() {
enum M = 500_000;
foreach (immutable n; 3 .. 7)
writefln("%d: %2.3f%% %2.3f%%", n,
M.iota.map!(_=> n.biased).sum * 100.0 / M,
M.iota.map!(_=> n.unbiased).sum * 100.0 / M);
} |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
An untouchable are those numbers that are not in the image of the aliquot sum function. (From Wikipedia)
Untouchable numbers: impossible values for the sum of all aliquot parts function. (From OEIS: The On-line Encyclopedia of Integer Sequences®)
An untouchable number is a positive integer that is not the sum of the proper divisors of any number. (From MathWorld™)
Observations and conjectures
All untouchable numbers > 5 are composite numbers.
No untouchable number is perfect.
No untouchable number is sociable.
No untouchable number is a Mersenne prime.
No untouchable number is one more than a prime number, since if p is prime, then
the sum of the proper divisors of p2 is p + 1.
No untouchable number is three more than an odd prime number, since if p is an odd prime, then the
sum of the proper divisors of 2p is p + 3.
The number 5 is believed to be the only odd untouchable number, but this has not been proven: it would follow from a
slightly stronger version of the Goldbach's conjecture, since the sum of the
proper divisors of pq (with p, q being
distinct primes) is 1 + p + q.
There are infinitely many untouchable numbers, a fact that was proven
by Paul Erdős.
According to Chen & Zhao, their natural density is at least d > 0.06.
Task
show (in a grid format) all untouchable numbers ≤ 2,000.
show (for the above) the count of untouchable numbers.
show the count of untouchable numbers from unity up to (inclusive):
10
100
1,000
10,000
100,000
... or as high as is you think is practical.
all output is to be shown here, on this page.
See also
Wolfram MathWorld: untouchable number.
OEIS: A005114 untouchable numbers.
OEIS: a list of all untouchable numbers below 100,000 (inclusive).
Wikipedia: untouchable number.
Wikipedia: Goldbach's conjecture.
| #Phix | Phix | constant limz = {1,1,8,9,18,64} -- found by experiment
procedure untouchable(integer n, cols=0, tens=0)
atom t0 = time(), t1 = t0+1
bool tell = n>0
n = abs(n)
sequence sums = repeat(0,n+3)
for i=1 to n do
integer p = get_prime(i)
if p>n then exit end if
sums[p+1] = 1
sums[p+3] = 1
end for
sums[5] = 0
integer m = floor(log10(n))
integer lim = limz[m]*n
for j=2 to lim do
integer y = sum(factors(j,-1))
if y<=n then
sums[y] = 1
end if
if platform()!=JS and time()>t1 then
progress("j:%,d/%,d (%3.2f%%)\r",{j,lim,(j/lim)*100})
t1 = time()+1
end if
end for
if platform()!=JS then progress("") end if
if tell then
printf(1,"The list of all untouchable numbers <= %d:\n",{n})
end if
string line = " 2 5"
integer cnt = 2
for t=6 to n by 2 do
if sums[t]=0 then
cnt += 1
if tell then
line &= sprintf("%,8d",t)
if remainder(cnt,cols)=0 then
printf(1,"%s\n",line)
line = ""
end if
end if
end if
end for
if tell then
if line!="" then
printf(1,"%s\n",line)
end if
printf(1,"\n")
end if
string t = elapsed(time()-t0,1," (%s)")
printf(1,"%,20d untouchable numbers were found <= %,d%s\n",{cnt,n,t})
for p=1 to tens do
untouchable(-power(10,p))
end for
end procedure
untouchable(2000, 10, 6-(platform()==JS))
|
http://rosettacode.org/wiki/Ukkonen%E2%80%99s_suffix_tree_construction | Ukkonen’s suffix tree construction | Suffix Trees are very useful in numerous string processing and computational biology problems.
The task is to create a function which implements Ukkonen’s algorithm to create a useful Suffix Tree as described:
Part 1
Part 2
Part 3
Part 4
Part 5
Part 6
Using Arithmetic-geometric mean/Calculate Pi generate the first 1000, 10000, and 100000 decimal places of pi. Using your implementation with an alphabet of 0 through 9 (plus $ say to make the tree explicit) find the longest repeated string in each list. Time your results and demonstrate that your implementation is linear (i.e. that 10000 takes approx. 10 times as long as 1000). You may vary the size of the lists of decimal places of pi to give reasonable answers.
| #Julia | Julia | const oo = typemax(Int)
"""The suffix-tree's node."""
mutable struct Node
children::Dict{Char, Int}
start::Int
ending::Int
suffixlink::Int
suffixindex::Int
end
Node() = Node(Dict(), 0, oo, 0, -1)
Node(start, ending) = Node(Dict(), start, ending, 0, -1)
""" Ukkonen Suffix-Tree """
mutable struct SuffixTree
nodes::Vector{Node}
text::Vector{Char}
root::Int
position::Int
currentnode::Int
needsuffixlink::Int
remainder::Int
activenode::Int
activelength::Int
activeedge::Int
end
edgelength(st, n::Node) = min(n.ending, st.position + 1) - n.start
function newnode(st, start, ending)
st.currentnode += 1
st.nodes[st.currentnode] = Node(start, ending)
return st.currentnode
end
function SuffixTree(str::String)
nodes = [Node() for _ in 1:length(str) * 2]
st = SuffixTree(nodes, [c for c in str], 1, 0, 0, 0, 0, 1, 1, 1)
st.root = newnode(st, 0, 0)
st.activenode = st.root
for i in 1:length(st.text)
extendsuffixtree(st, i)
end
setsuffixindexbyDFS(st, st.nodes[st.root], 0)
return st
end
function addsuffixlink(st, nodenum::Int)
if st.needsuffixlink > 0
st.nodes[st.needsuffixlink].suffixlink = nodenum
end
st.needsuffixlink = nodenum
end
activeedge(st) = st.text[st.activeedge]
function walkdown!(st, currnode::Int)
len = edgelength(st, st.nodes[currnode])
st.activelength < len && return false
st.activeedge += len
st.activelength -= len
st.activenode = currnode
return true
end
function extendsuffixtree(st, pos)
st.position = pos
st.needsuffixlink = 0
st.remainder += 1
while st.remainder > 0
st.activelength == 0 && (st.activeedge = st.position)
if !haskey(st.nodes[st.activenode].children, activeedge(st))
nodenum = newnode(st, st.position, oo)
st.nodes[st.activenode].children[activeedge(st)] = nodenum
addsuffixlink(st, st.activenode)
else
next = st.nodes[st.activenode].children[activeedge(st)]
walkdown!(st, next) && continue
if st.text[st.nodes[next].start + st.activelength] == st.text[pos]
addsuffixlink(st, st.activenode)
st.activelength += 1
break
end
splt = newnode(st, st.nodes[next].start, st.nodes[next].start + st.activelength)
st.nodes[st.activenode].children[activeedge(st)] = splt
nodenum = newnode(st, st.position, oo)
st.nodes[splt].children[st.text[pos]] = nodenum
st.nodes[next].start += st.activelength
st.nodes[splt].children[st.text[st.nodes[next].start]] = next
addsuffixlink(st, splt)
end
st.remainder -= 1
if st.activenode == st.root && st.activelength > 0
st.activelength -= 1
st.activeedge = st.position - st.remainder + 1
elseif st.activenode != st.root
st.activenode = st.nodes[st.activenode].suffixlink
end
end
end
function setsuffixindexbyDFS(st, node, labelheight, verbose=false)
verbose && node.start > 0 && print(st.text[node.start:min(node.ending, length(st.text))])
isleaf = true
for child in map(v -> st.nodes[v], collect(values(node.children)))
verbose && isleaf && node.start > 0 && println(" [", node.suffixindex, "]")
isleaf = false
setsuffixindexbyDFS(st, child, labelheight + edgelength(st, child))
end
if isleaf
idx = length(st.text) - labelheight
node.suffixindex = idx
verbose && println(" [$idx]")
end
end
function dotraversal(st)
maxheight, substringstartindices = 0, [0]
function traversal(node::Node, labelheight)
if node.suffixindex == -1
for child in map(v -> st.nodes[v], collect(values(node.children)))
traversal(child, labelheight + edgelength(st, child))
end
elseif maxheight < labelheight - edgelength(st, node)
maxheight = labelheight - edgelength(st, node)
substringstartindices = [node.suffixindex + 1]
elseif maxheight == labelheight - edgelength(st, node)
push!(substringstartindices, node.suffixindex + 1)
end
end
traversal(st.nodes[st.root], 0)
return maxheight, substringstartindices
end
function getlongestrepeatedsubstring(st::SuffixTree, label="", printresult=true)
len, starts = dotraversal(st)
substring = len == 0 ? "" :
join(unique(map(x -> String(st.text[x:x+len-1]), starts)), " (or) ")
if printresult
print(" ", label == "" ? String(st.text) : label, ": ")
println(len == 0 ? "No repeated substring." : substring)
end
return substring
end
function testsuffixtree()
tests = [
"CAAAABAAAABD\$",
"GEEKSFORGEEKS\$",
"AAAAAAAAAA\$",
"ABCDEFG\$",
"ABABABA\$",
"ATCGATCGA\$",
"banana\$",
"abcpqrabpqpq\$",
"pqrpqpqabab\$",
]
println("Longest Repeated Substring in:\n")
for test in tests
st = SuffixTree(test)
getlongestrepeatedsubstring(st)
end
println()
sπ = ""
setprecision(4000000) do
sπ = string(BigFloat(π))[3:end]
end
for number in [1000, 10000, 100000, 1000000]
text = sπ[1:number] * "\$"
@time begin
st = SuffixTree(text)
getlongestrepeatedsubstring(st, "first $number d.p. of π")
end
end
end
testsuffixtree()
|
http://rosettacode.org/wiki/Ukkonen%E2%80%99s_suffix_tree_construction | Ukkonen’s suffix tree construction | Suffix Trees are very useful in numerous string processing and computational biology problems.
The task is to create a function which implements Ukkonen’s algorithm to create a useful Suffix Tree as described:
Part 1
Part 2
Part 3
Part 4
Part 5
Part 6
Using Arithmetic-geometric mean/Calculate Pi generate the first 1000, 10000, and 100000 decimal places of pi. Using your implementation with an alphabet of 0 through 9 (plus $ say to make the tree explicit) find the longest repeated string in each list. Time your results and demonstrate that your implementation is linear (i.e. that 10000 takes approx. 10 times as long as 1000). You may vary the size of the lists of decimal places of pi to give reasonable answers.
| #Phix | Phix | -- demo/rosetta/Ukkonens_Suffix_Tree.exw
with javascript_semantics
integer maxChar = 'z'
sequence children = {},
suffixLinks = {},
starts = {},
endIndices = {},
suffixIndices = {},
leaves = {}
function new_leaf(integer v=0)
leaves = append(leaves,v)
return length(leaves)
end function
string text
integer splitEndIdx,
rootEndIdx,
leafEndIdx = new_leaf(),
root = NULL,
lastNewNode,
activeNode,
activeEdge = -1,
activeLength = 0,
remainingSuffixCount = 0,
size = -1
function newNode(integer start, finishIdx, bool bKids=false)
children = append(children,iff(bKids?repeat(NULL,maxChar):0))
suffixLinks = append(suffixLinks,root)
starts = append(starts,start)
endIndices = append(endIndices,finishIdx)
suffixIndices = append(suffixIndices,-1)
return length(children)
end function
function edgeLength(integer n)
return iff(n==root?0:leaves[endIndices[n]] - starts[n] + 1)
end function
function walkDown(integer currNode)
integer l = edgeLength(currNode)
if activeLength >= l then
activeEdge += l
activeLength -= l
activeNode = currNode
return true
end if
return false
end function
procedure extendSuffixTree(integer pos)
leaves[leafEndIdx] = pos
remainingSuffixCount += 1
lastNewNode = NULL
while remainingSuffixCount > 0 do
if activeLength == 0 then
activeEdge = pos
end if
integer ta = text[activeEdge]
bool ca0 = children[activeNode]=0
integer next = iff(ca0?NULL:children[activeNode][ta])
if next==null then
if ca0 then
children[activeNode] = repeat(NULL,maxChar)
end if
children[activeNode][ta] = newNode(pos, leafEndIdx)
if lastNewNode!=NULL then
suffixLinks[lastNewNode] = activeNode
lastNewNode = NULL
end if
else
if walkDown(next) then
continue
end if
integer tp = text[pos]
if text[starts[next]+activeLength] == tp then
if lastNewNode!=NULL and activeNode!=root then
suffixLinks[lastNewNode] = activeNode
lastNewNode = NULL
end if
activeLength += 1
exit
end if
integer temp = starts[next] + activeLength - 1
splitEndIdx = new_leaf(temp)
integer splitnode = newNode(starts[next], splitEndIdx, true)
ta = text[activeEdge]
children[activeNode][ta] = splitnode
children[splitnode][tp] = newNode(pos, leafEndIdx)
starts[next] += activeLength
children[splitnode][text[starts[next]]] = next
if lastNewNode!=NULL then
suffixLinks[lastNewNode] = splitnode
end if
lastNewNode = splitnode
end if
remainingSuffixCount -= 1
if activeNode==root and activeLength>0 then
activeLength -= 1
activeEdge = pos - remainingSuffixCount + 1
elsif activeNode!=root then
activeNode = suffixLinks[activeNode]
end if
end while
end procedure
procedure setSuffixIndexByDFS(integer n, labelHeight)
if n!=NULL then
if children[n]=0 then
suffixIndices[n] = size - labelHeight
else
bool leaf = true
for i=1 to maxChar do
integer nci = children[n][i]
if nci!=NULL then
leaf = false
setSuffixIndexByDFS(nci, labelHeight+edgeLength(nci))
end if
end for
if leaf then ?9/0 end if -- (sanity check)
end if
end if
end procedure
procedure buildSuffixTree()
size = length(text)
rootEndIdx = new_leaf(-1)
root = newNode(-1, rootEndIdx)
activeNode = root
for i=1 to size do
extendSuffixTree(i)
end for
integer labelHeight = 0
setSuffixIndexByDFS(root, labelHeight)
end procedure
procedure doTraversal(integer n, labelHeight, maxHeightIdx, substringStartIndex)
if n!=NULL then
integer nsi = suffixIndices[n], newHeight
if nsi == -1 then
for i=1 to maxChar do
integer nci = children[n][i]
if nci!=NULL then
newHeight = labelHeight+edgeLength(nci)
doTraversal(nci, newHeight, maxHeightIdx, substringStartIndex)
end if
end for
elsif nsi > -1 then
newHeight = labelHeight-edgeLength(n)
if leaves[maxHeightIdx]<newHeight then
leaves[maxHeightIdx] = newHeight
leaves[substringStartIndex] = nsi
end if
end if
end if
end procedure
function getLongestRepeatedSubstring()
integer maxHeightIdx = new_leaf(),
substringStartIndex = new_leaf()
doTraversal(root, 0, maxHeightIdx, substringStartIndex)
integer maxHeight = leaves[maxHeightIdx],
start = leaves[substringStartIndex]
string t = iff(maxHeight=0?"No repeated substring"
:text[start+1..start+maxHeight])
return t
end function
constant tests = {"CAAAABAAAABD$",
"GEEKSFORGEEKS$",
"AAAAAAAAAA$",
"ABCDEFG$",
"ABABABA$",
"ATCGATCGA$",
"banana$",
"abcpqrabpqpq$",
"pqrpqpqabab$"}
printf(1,"Longest Repeated Substring in:\n")
for i=1 to length(tests) do
text = tests[i]
buildSuffixTree()
printf(1," %s is: %s\n", {text,getLongestRepeatedSubstring()})
end for
printf(1,"\n")
include mpfr.e
string piStr
if platform()=JS then
mpfr pi = mpfr_init(0,-1001) -- (set precision to 1,000 dp, plus the "3.")
mpfr_const_pi(pi)
piStr = mpfr_get_fixed(pi,1000) -- (all we can really manage under pwa/p2js)
else
-- gmp crashes when I try 100,000 dp, so just get from file
piStr = get_text(`E:\downloads\misc\arm\pi-10million.txt`)
end if
piStr = piStr[3..$] -- discard leading "3."
maxChar = '9'
for i=3 to iff(platform()=JS?3:6) do
atom t0 = time()
integer n = power(10,i)
text = piStr[1..n] & "$"
buildSuffixTree()
string r = getLongestRepeatedSubstring(),
e = elapsed(time()-t0)
printf(1," first %,d d.p. of Pi is: %s (%s)\n", {n,r,e})
end for
|
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Haskell | Haskell | import Control.Monad
import Data.List
import System.Directory
dontStartWith = flip $ (/=) . head
main = do
files <- getDirectoryContents "."
mapM_ putStrLn $ sort $ filter (dontStartWith '.') files |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #J | J | dir '' NB. includes properties
>1 1 dir '' NB. plain filename as per task |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #Ring | Ring |
# Project : Vector products
d = list(3)
e = list(3)
a = [3, 4, 5]
b = [4, 3, 5]
c = [-5, -12, -13]
see "a . b = " + dot(a,b) + nl
cross(a,b,d)
see "a x b = (" + d[1] + ", " + d[2] + ", " + d[3] + ")" + nl
see "a . (b x c) = " + scalartriple(a,b,c) + nl
vectortriple(a,b,c,d)
def dot(a,b)
sum = 0
for n=1 to len(a)
sum = sum + a[n]*b[n]
next
return sum
func cross(a,b,d)
d = [a[2]*b[3]-a[3]*b[2], a[3]*b[1]-a[1]*b[3], a[1]*b[2]-a[2]*b[1]]
func scalartriple(a,b,c)
cross(b,c,d)
return dot(a,d)
func vectortriple(a,b,c,d)
cross(b,c,d)
cross(a,d,e)
see "a x (b x c) = (" + e[1] + ", " +e[2] + ", " + e[3] + ")"
|
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Vedit_macro_language | Vedit macro language | Get_Input(1, "Enter a string: ")
#2 = Get_Num("Enter a number: ") |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Visual_Basic_.NET | Visual Basic .NET | Dim i As Integer
Console.WriteLine("Enter an Integer")
i = Console.ReadLine() |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #OCaml | OCaml | (* There is no undefined value in OCaml,
but if you really need this you can use the built-in "option" type.
It is defined like this: type 'a option = None | Some of 'a *)
let inc = function
Some n -> Some (n+1)
| None -> failwith "Undefined argument";;
inc (Some 0);;
(* - : value = Some 1 *)
inc None;;
(* Exception: Failure "Undefined argument". *) |
|
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Oforth | Oforth | declare X in
thread
if {IsFree X} then {System.showInfo "X is unbound."} end
{Wait X}
{System.showInfo "Now X is determined."}
end
{System.showInfo "Sleeping..."}
{Delay 1000}
{System.showInfo "Setting X."}
X = 42 |
|
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #Erlang | Erlang | var i int
var u rune
for i, u = range "voilà" {
fmt.Println(i, u)
} |
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #Go | Go | var i int
var u rune
for i, u = range "voilà" {
fmt.Println(i, u)
} |
http://rosettacode.org/wiki/Unprimeable_numbers | Unprimeable numbers | Definitions
As used here, all unprimeable numbers (positive integers) are always expressed in base ten.
───── Definition from OEIS ─────:
Unprimeable numbers are composite numbers that always remain composite when a single decimal digit of the number is changed.
───── Definition from Wiktionary (referenced from Adam Spencer's book) ─────:
(arithmetic) that cannot be turned into a prime number by changing just one of its digits to any other
digit. (sic)
Unprimeable numbers are also spelled: unprimable.
All one─ and two─digit numbers can be turned into primes by changing a single decimal digit.
Examples
190 isn't unprimeable, because by changing the zero digit into a three yields 193, which is a prime.
The number 200 is unprimeable, since none of the numbers 201, 202, 203, ··· 209 are
prime, and all the other numbers obtained by changing a single digit to
produce 100, 300, 400, ··· 900, or 210, 220, 230, ··· 290 which are all even.
It is valid to change 189 into 089 by changing the 1 (one) into
a 0 (zero), which then the leading zero can be removed, and then treated as if
the "new" number is 89.
Task
show the first 35 unprimeable numbers (horizontally, on one line, preferably with a title)
show the 600th unprimeable number
(optional) show the lowest unprimeable number ending in a specific decimal digit (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
(optional) use commas in the numbers where appropriate
Show all output here, on this page.
Also see
the OEIS entry: A118118 (unprimeable)
with some useful counts to compare unprimeable number
the Wiktionary entry (reference from below): (arithmetic definition) unprimeable
from the Adam Spencer book (page 200): Adam Spencer's World of Numbers (Xoum Publishing)
| #Go | Go | package main
import (
"fmt"
"strconv"
)
func isPrime(n int) bool {
switch {
case n < 2:
return false
case n%2 == 0:
return n == 2
case n%3 == 0:
return n == 3
default:
d := 5
for d*d <= n {
if n%d == 0 {
return false
}
d += 2
if n%d == 0 {
return false
}
d += 4
}
return true
}
}
func commatize(n int) string {
s := fmt.Sprintf("%d", n)
le := len(s)
for i := le - 3; i >= 1; i -= 3 {
s = s[0:i] + "," + s[i:]
}
return s
}
func main() {
fmt.Println("The first 35 unprimeable numbers are:")
count := 0 // counts all unprimeable numbers
var firstNum [10]int // stores the first unprimeable number ending with each digit
outer:
for i, countFirst := 100, 0; countFirst < 10; i++ {
if isPrime(i) {
continue // unprimeable number must be composite
}
s := strconv.Itoa(i)
le := len(s)
b := []byte(s)
for j := 0; j < le; j++ {
for k := byte('0'); k <= '9'; k++ {
if s[j] == k {
continue
}
b[j] = k
n, _ := strconv.Atoi(string(b))
if isPrime(n) {
continue outer
}
}
b[j] = s[j] // restore j'th digit to what it was originally
}
lastDigit := s[le-1] - '0'
if firstNum[lastDigit] == 0 {
firstNum[lastDigit] = i
countFirst++
}
count++
if count <= 35 {
fmt.Printf("%d ", i)
}
if count == 35 {
fmt.Print("\n\nThe 600th unprimeable number is: ")
}
if count == 600 {
fmt.Printf("%s\n\n", commatize(i))
}
}
fmt.Println("The first unprimeable number that ends in:")
for i := 0; i < 10; i++ {
fmt.Printf(" %d is: %9s\n", i, commatize(firstNum[i]))
}
} |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Julia | Julia | julia> Δ = 1 ; Δ += 1 ; Δ
2 |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Kotlin | Kotlin | fun main(args: Array<String>) {
var Δ = 1
Δ++
print(Δ)
} |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Lily | Lily | var Δ = 1
Δ += 1
print(Δ.to_s()) |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Lingo | Lingo | Δ = 1
Δ = Δ + 1
put Δ
-- 2 |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #Elena | Elena | import extensions;
extension op : IntNumber
{
bool randN()
= randomGenerator.nextInt(self) == 0;
get bool Unbiased()
{
bool flip1 := self.randN();
bool flip2 := self.randN();
while (flip1 == flip2)
{
flip1 := self.randN();
flip2 := self.randN()
};
^ flip1
}
}
public program()
{
for(int n := 3, n <= 6, n += 1)
{
int biasedZero := 0;
int biasedOne := 0;
int unbiasedZero := 0;
int unbiasedOne := 0;
for(int i := 0, i < 100000, i += 1)
{
if(n.randN()) { biasedOne += 1 } else { biasedZero += 1 };
if(n.Unbiased) { unbiasedOne += 1 } else { unbiasedZero += 1 }
};
console
.printLineFormatted("(N = {0}):".padRight(17) + "# of 0"$9"# of 1"$9"% of 0"$9"% of 1", n)
.printLineFormatted("Biased:".padRight(15) + "{0}"$9"{1}"$9"{2}"$9"{3}",
biasedZero, biasedOne, biasedZero / 1000, biasedOne / 1000)
.printLineFormatted("Unbiased:".padRight(15) + "{0}"$9"{1}"$9"{2}"$9"{3}",
unbiasedZero, unbiasedOne, unbiasedZero / 1000, unbiasedOne / 1000)
}
} |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #Elixir | Elixir | defmodule Random do
def randN(n) do
if :rand.uniform(n) == 1, do: 1, else: 0
end
def unbiased(n) do
{x, y} = {randN(n), randN(n)}
if x != y, do: x, else: unbiased(n)
end
end
IO.puts "N biased unbiased"
m = 10000
for n <- 3..6 do
xs = for _ <- 1..m, do: Random.randN(n)
ys = for _ <- 1..m, do: Random.unbiased(n)
IO.puts "#{n} #{Enum.sum(xs) / m} #{Enum.sum(ys) / m}"
end |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
An untouchable are those numbers that are not in the image of the aliquot sum function. (From Wikipedia)
Untouchable numbers: impossible values for the sum of all aliquot parts function. (From OEIS: The On-line Encyclopedia of Integer Sequences®)
An untouchable number is a positive integer that is not the sum of the proper divisors of any number. (From MathWorld™)
Observations and conjectures
All untouchable numbers > 5 are composite numbers.
No untouchable number is perfect.
No untouchable number is sociable.
No untouchable number is a Mersenne prime.
No untouchable number is one more than a prime number, since if p is prime, then
the sum of the proper divisors of p2 is p + 1.
No untouchable number is three more than an odd prime number, since if p is an odd prime, then the
sum of the proper divisors of 2p is p + 3.
The number 5 is believed to be the only odd untouchable number, but this has not been proven: it would follow from a
slightly stronger version of the Goldbach's conjecture, since the sum of the
proper divisors of pq (with p, q being
distinct primes) is 1 + p + q.
There are infinitely many untouchable numbers, a fact that was proven
by Paul Erdős.
According to Chen & Zhao, their natural density is at least d > 0.06.
Task
show (in a grid format) all untouchable numbers ≤ 2,000.
show (for the above) the count of untouchable numbers.
show the count of untouchable numbers from unity up to (inclusive):
10
100
1,000
10,000
100,000
... or as high as is you think is practical.
all output is to be shown here, on this page.
See also
Wolfram MathWorld: untouchable number.
OEIS: A005114 untouchable numbers.
OEIS: a list of all untouchable numbers below 100,000 (inclusive).
Wikipedia: untouchable number.
Wikipedia: Goldbach's conjecture.
| #Raku | Raku | # 20210220 Raku programming solution
sub propdiv (\x) {
my @l = 1 if x > 1;
(2 .. x.sqrt.floor).map: -> \d {
unless x % d { @l.push: d; my \y = x div d; @l.push: y if y != d }
}
@l
}
sub sieve (\n) {
my %s;
for (0..(n+1)) -> \k {
given ( [+] propdiv k ) { %s{$_} = True if $_ ≤ (n+1) }
}
%s;
}
my \limit = 1e5;
my %c = ( grep { !.is-prime }, 1..limit ).Set; # store composites
my %s = sieve(14 * limit);
my @untouchable = 2, 5;
loop ( my \n = $ = 6 ; n ≤ limit ; n += 2 ) {
@untouchable.append(n) if (!%s{n} && %c{n-1} && %c{n-3})
}
my ($c, $last) = 0, False;
for @untouchable.rotor(10) {
say [~] @_».&{$c++ ; $_ > 2000 ?? ( $last = True and last ) !! .fmt: "%6d "}
$c-- and last if $last
}
say "\nList of untouchable numbers ≤ 2,000 : $c \n";
my ($p, $count) = 10,0;
BREAK: for @untouchable -> \n {
$count++;
if (n > $p) {
printf "%6d untouchable numbers were found ≤ %7d\n", $count-1, $p;
last BREAK if limit == ($p *= 10)
}
}
printf "%6d untouchable numbers were found ≤ %7d\n", +@untouchable, limit |
http://rosettacode.org/wiki/Two_bullet_roulette | Two bullet roulette | The following is supposedly a question given to mathematics graduates seeking jobs on Wall Street:
A revolver handgun has a revolving cylinder with six chambers for bullets.
It is loaded with the following procedure:
1. Check the first chamber to the right of the trigger for a bullet. If a bullet
is seen, the cylinder is rotated one chamber clockwise and the next chamber
checked until an empty chamber is found.
2. A cartridge containing a bullet is placed in the empty chamber.
3. The cylinder is then rotated one chamber clockwise.
To randomize the cylinder's position, the cylinder is spun, which causes the cylinder to take
a random position from 1 to 6 chamber rotations clockwise from its starting position.
When the trigger is pulled the gun will fire if there is a bullet in position 0, which is just
counterclockwise from the loading position.
The gun is unloaded by removing all cartridges from the cylinder.
According to the legend, a suicidal Russian imperial military officer plays a game of Russian
roulette by putting two bullets in a six-chamber cylinder and pulls the trigger twice.
If the gun fires with a trigger pull, this is considered a successful suicide.
The cylinder is always spun before the first shot, but it may or may not be spun after putting
in the first bullet and may or may not be spun after taking the first shot.
Which of the following situations produces the highest probability of suicide?
A. Spinning the cylinder after loading the first bullet, and spinning again after the first shot.
B. Spinning the cylinder after loading the first bullet only.
C. Spinning the cylinder after firing the first shot only.
D. Not spinning the cylinder either after loading the first bullet or after the first shot.
E. The probability is the same for all cases.
Task
Run a repeated simulation of each of the above scenario, calculating the percentage of suicide with a randomization of the four spinning, loading and firing order scenarios.
Show the results as a percentage of deaths for each type of scenario.
The hand calculated probabilities are 5/9, 7/12, 5/9, and 1/2. A correct program should produce results close enough to those to allow a correct response to the interview question.
Reference
Youtube video on the Russian 1895 Nagant revolver [[1]]
| #11l | 11l | UInt32 seed = 0
F nonrandom(n)
:seed = 1664525 * :seed + 1013904223
R Int(:seed >> 16) % n
V cylinder = [0B] * 6
F rshift()
V t = :cylinder[5]
L(i) (4..0).step(-1)
:cylinder[i + 1] = :cylinder[i]
:cylinder[0] = t
F unload()
L(i) 6
:cylinder[i] = 0B
F load()
L :cylinder[0]
rshift()
:cylinder[0] = 1B
rshift()
F spin()
L 1..nonrandom(6)
rshift()
F fire()
V shot = :cylinder[0]
rshift()
R shot
F method(s)
unload()
L(c) s
S c
‘L’
load()
‘S’
spin()
‘F’
I fire()
R 1
R 0
F mstring(s)
[String] l
L(c) s
S c
‘L’
l [+]= ‘load’
‘S’
l [+]= ‘spin’
‘F’
l [+]= ‘fire’
R l.join(‘, ’)
V tests = 100000
L(m) [‘LSLSFSF’, ‘LSLSFF’, ‘LLSFSF’, ‘LLSFF’]
V sum = 0
L 0 .< tests
sum += method(m)
V pc = Float(sum) * 100 / tests
print(‘#<40 produces #2.3% deaths.’.format(mstring(m), pc)) |
http://rosettacode.org/wiki/Ukkonen%E2%80%99s_suffix_tree_construction | Ukkonen’s suffix tree construction | Suffix Trees are very useful in numerous string processing and computational biology problems.
The task is to create a function which implements Ukkonen’s algorithm to create a useful Suffix Tree as described:
Part 1
Part 2
Part 3
Part 4
Part 5
Part 6
Using Arithmetic-geometric mean/Calculate Pi generate the first 1000, 10000, and 100000 decimal places of pi. Using your implementation with an alphabet of 0 through 9 (plus $ say to make the tree explicit) find the longest repeated string in each list. Time your results and demonstrate that your implementation is linear (i.e. that 10000 takes approx. 10 times as long as 1000). You may vary the size of the lists of decimal places of pi to give reasonable answers.
| #Wren | Wren | import "/big" for BigRat
import "/dynamic" for Struct
import "/trait" for ByRef
import "io" for File
var maxChar = 128
var Node = Struct.create("Node", ["children", "suffixLink", "start", "pEnd", "suffixIndex"])
var text = ""
var root = null
var lastNewNode = null
var activeNode = null
var activeEdge = -1
var activeLength = 0
var remainingSuffixCount = 0
var pLeafEnd = ByRef.new(-1)
var pRootEnd = null
var pSplitEnd = null
var size = -1
var newNode = Fn.new { |start, pEnd|
var children = List.filled(maxChar, null)
var suffixLink = root
var suffixIndex = -1
return Node.new(children, suffixLink, start, pEnd, suffixIndex)
}
var edgeLength = Fn.new { |n|
if (n == root) return 0
return n.pEnd.value - n.start + 1
}
var walkDown = Fn.new { |currNode|
var el = edgeLength.call(currNode)
if (activeLength >= el) {
activeEdge = activeEdge + el
activeLength = activeLength - el
activeNode = currNode
return true
}
return false
}
var extendSuffixTree = Fn.new { |pos|
pLeafEnd.value = pos
remainingSuffixCount = remainingSuffixCount + 1
lastNewNode = null
while (remainingSuffixCount > 0) {
if (activeLength == 0) activeEdge = pos
if (!activeNode.children[text[activeEdge].bytes[0]]) {
activeNode.children[text[activeEdge].bytes[0]] = newNode.call(pos, pLeafEnd)
if (lastNewNode) {
lastNewNode.suffixLink = activeNode
lastNewNode = null
}
} else {
var next = activeNode.children[text[activeEdge].bytes[0]]
if (walkDown.call(next)) continue
if (text[next.start + activeLength] == text[pos]) {
if (lastNewNode && activeNode != root) {
lastNewNode.suffixLink = activeNode
lastNewNode = null
}
activeLength = activeLength + 1
break
}
var temp = next.start + activeLength - 1
pSplitEnd = ByRef.new(temp)
var split = newNode.call(next.start, pSplitEnd)
activeNode.children[text[activeEdge].bytes[0]] = split
split.children[text[pos].bytes[0]] = newNode.call(pos, pLeafEnd)
next.start = next.start + activeLength
split.children[text[next.start].bytes[0]] = next
if (lastNewNode) lastNewNode.suffixLink = split
lastNewNode = split
}
remainingSuffixCount = remainingSuffixCount - 1
if (activeNode == root && activeLength > 0) {
activeLength = activeLength - 1
activeEdge = pos - remainingSuffixCount + 1
} else if (activeNode != root) {
activeNode = activeNode.suffixLink
}
}
}
var setSuffixIndexByDFS // recursive
setSuffixIndexByDFS = Fn.new { |n, labelHeight|
if (!n) return
if (n.start != -1) {
// Uncomment line below to print suffix tree
// System.write(text[n.start..n.pEnd.value])
}
var leaf = 1
for (i in 0...maxChar) {
if (n.children[i]) {
// Uncomment the 3 lines below to print suffix index
// if (leaf == 1 && n.start != -1) {
// System.print(" [%(n.suffixIndex)]")
// }
leaf = 0
setSuffixIndexByDFS.call(n.children[i], labelHeight + edgeLength.call(n.children[i]))
}
}
if (leaf == 1) {
n.suffixIndex = size - labelHeight
// Uncomment line below to print suffix index
// System.print(" [%(n.suffixIndex)]")
}
}
var buildSuffixTree = Fn.new {
size = text.count
var temp = -1
pRootEnd = ByRef.new(temp)
root = newNode.call(-1, pRootEnd)
activeNode = root
for (i in 0...size) extendSuffixTree.call(i)
var labelHeight = 0
setSuffixIndexByDFS.call(root, labelHeight)
}
var doTraversal // recursive
doTraversal = Fn.new { |n, labelHeight, pMaxHeight, pSubstringStartIndex|
if (!n) return
if (n.suffixIndex == -1) {
for (i in 0...maxChar) {
if (n.children[i]) {
doTraversal.call(n.children[i], labelHeight + edgeLength.call(n.children[i]),
pMaxHeight, pSubstringStartIndex)
}
}
} else if (n.suffixIndex > -1 && (pMaxHeight.value < labelHeight - edgeLength.call(n))) {
pMaxHeight.value = labelHeight - edgeLength.call(n)
pSubstringStartIndex.value = n.suffixIndex
}
}
var getLongestRepeatedSubstring = Fn.new { |s|
var maxHeight = 0
var substringStartIndex = 0
var pMaxHeight = ByRef.new(maxHeight)
var pSubstringStartIndex = ByRef.new(substringStartIndex)
doTraversal.call(root, 0, pMaxHeight, pSubstringStartIndex)
maxHeight = pMaxHeight.value
substringStartIndex = pSubstringStartIndex.value
// Uncomment line below to print maxHeight and substringStartIndex
// System.print("maxHeight %(maxHeight), substringStartIndex %(substringStartIndex)")
if (s == "") {
System.write(" %(text) is: ")
} else {
System.write(" %(s) is: ")
}
var k = 0
while (k < maxHeight) {
System.write(text[k + substringStartIndex])
k = k + 1
}
if (k == 0) {
System.write("No repeated substring")
}
System.print()
}
var tests = [
"GEEKSFORGEEKS$",
"AAAAAAAAAA$",
"ABCDEFG$",
"ABABABA$",
"ATCGATCGA$",
"banana$",
"abcpqrabpqpq$",
"pqrpqpqabab$",
]
System.print("Longest Repeated Substring in:\n")
for (test in tests) {
text = test
buildSuffixTree.call()
getLongestRepeatedSubstring.call("")
}
System.print()
// load pi to 100,182 digits
var piStr = File.read("pi_100000.txt")
piStr = piStr[2..-1] // remove initial 3.
var numbers = [1e3, 1e4, 1e5]
maxChar = 58
for (number in numbers) {
var start = System.clock
text = piStr[0...number] + "$"
buildSuffixTree.call()
getLongestRepeatedSubstring.call("first %(number) d.p. of Pi")
var elapsed = (System.clock - start) * 1000
System.print(" (this took %(elapsed) ms)\n")
} |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Java | Java |
package rosetta;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
public class UnixLS {
public static void main(String[] args) throws IOException {
Files.list(Path.of("")).sorted().forEach(System.out::println);
}
}
|
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #JavaScript | JavaScript | const fs = require('fs');
fs.readdir('.', (err, names) => names.sort().map( name => console.log(name) )); |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #Ruby | Ruby | require 'matrix'
class Vector
def scalar_triple_product(b, c)
self.inner_product(b.cross_product c)
end
def vector_triple_product(b, c)
self.cross_product(b.cross_product c)
end
end
a = Vector[3, 4, 5]
b = Vector[4, 3, 5]
c = Vector[-5, -12, -13]
puts "a dot b = #{a.inner_product b}"
puts "a cross b = #{a.cross_product b}"
puts "a dot (b cross c) = #{a.scalar_triple_product b, c}"
puts "a cross (b cross c) = #{a.vector_triple_product b, c}" |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Vlang | Vlang | import os
fn main() {
s := os.input('Enter string').int()
if s == 75000 {
println('good')
} else {
println('bad')
}
} |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Input_conversion_with_Error_Handling | Input conversion with Error Handling | import os
import strconv
fn main() {
s := strconv.atoi(os.input('Enter string')) ?
if s == 75000 {
println('good')
} else {
println('bad $s')
}
} |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Oz | Oz | declare X in
thread
if {IsFree X} then {System.showInfo "X is unbound."} end
{Wait X}
{System.showInfo "Now X is determined."}
end
{System.showInfo "Sleeping..."}
{Delay 1000}
{System.showInfo "Setting X."}
X = 42 |
|
http://rosettacode.org/wiki/Undefined_values | Undefined values | #PARI.2FGP | PARI/GP | v == 'v |
|
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #Haskell | Haskell | '♥♦♣♠'
♥♦♣♠ |
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #J | J | '♥♦♣♠'
♥♦♣♠ |
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for Unicode?
Task
Discuss and demonstrate its unicode awareness and capabilities.
Some suggested topics:
How easy is it to present Unicode strings in source code?
Can Unicode literals be written directly, or be part of identifiers/keywords/etc?
How well can the language communicate with the rest of the world?
Is it good at input/output with Unicode?
Is it convenient to manipulate Unicode strings in the language?
How broad/deep does the language support Unicode?
What encodings (e.g. UTF-8, UTF-16, etc) can be used?
Does it support normalization?
Note
This task is a bit unusual in that it encourages general discussion rather than clever coding.
See also
Unicode variable names
Terminal control/Display an extended character
| #Java | Java | --raw-input | -R :: each line of input is converted to a JSON string;
--ascii-output | -a :: every non-ASCII character that would otherwise
be sent to output is translated to an equivalent
ASCII escape sequence;
--raw-output | -r :: output strings as raw strings, e.g. "a\nb" is
output as:
|
http://rosettacode.org/wiki/Unprimeable_numbers | Unprimeable numbers | Definitions
As used here, all unprimeable numbers (positive integers) are always expressed in base ten.
───── Definition from OEIS ─────:
Unprimeable numbers are composite numbers that always remain composite when a single decimal digit of the number is changed.
───── Definition from Wiktionary (referenced from Adam Spencer's book) ─────:
(arithmetic) that cannot be turned into a prime number by changing just one of its digits to any other
digit. (sic)
Unprimeable numbers are also spelled: unprimable.
All one─ and two─digit numbers can be turned into primes by changing a single decimal digit.
Examples
190 isn't unprimeable, because by changing the zero digit into a three yields 193, which is a prime.
The number 200 is unprimeable, since none of the numbers 201, 202, 203, ··· 209 are
prime, and all the other numbers obtained by changing a single digit to
produce 100, 300, 400, ··· 900, or 210, 220, 230, ··· 290 which are all even.
It is valid to change 189 into 089 by changing the 1 (one) into
a 0 (zero), which then the leading zero can be removed, and then treated as if
the "new" number is 89.
Task
show the first 35 unprimeable numbers (horizontally, on one line, preferably with a title)
show the 600th unprimeable number
(optional) show the lowest unprimeable number ending in a specific decimal digit (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
(optional) use commas in the numbers where appropriate
Show all output here, on this page.
Also see
the OEIS entry: A118118 (unprimeable)
with some useful counts to compare unprimeable number
the Wiktionary entry (reference from below): (arithmetic definition) unprimeable
from the Adam Spencer book (page 200): Adam Spencer's World of Numbers (Xoum Publishing)
| #Haskell | Haskell | import Control.Lens ((.~), ix, (&))
import Data.Numbers.Primes (isPrime)
import Data.List (find, intercalate)
import Data.Char (intToDigit)
import Data.Maybe (mapMaybe)
import Data.List.Split (chunksOf)
import Text.Printf (printf)
isUnprimable :: Int -> Bool
isUnprimable = all (not . isPrime) . swapdigits
swapdigits :: Int -> [Int]
swapdigits n = map read $ go $ pred $ length digits
where
digits = show n
go (-1) = []
go n'' = map (\x -> digits & (ix n'') .~ intToDigit x) [0..9] <> go (pred n'')
unPrimeable :: [Int]
unPrimeable = filter isUnprimable [1..]
main :: IO ()
main = do
printf "First 35 unprimeable numbers:\n%s\n\n" $ show $ take 35 unPrimeable
printf "600th unprimeable number: %d\n\n" $ unPrimeable !! 599
mapM_ (uncurry (printf "Lowest unprimeable number ending with %d: %10s\n")) $ mapMaybe lowest [0..9]
where
thousands = reverse . intercalate "," . chunksOf 3 . reverse
lowest n = do
x <- find (\x -> x `mod` 10 == n) unPrimeable
pure (n, thousands $ show x) |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #LiveCode | LiveCode | put 1 into Δ
add 1 to Δ
put Δ
-- result is 2 |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #LOLCODE | LOLCODE | I HAS A SRS "Δ" ITZ 1
SRS "Δ" R SUM OF SRS ":(394)" AN 1
VISIBLE SRS ":[GREEK CAPITAL LETTER DELTA]" |
http://rosettacode.org/wiki/Unicode_variable_names | Unicode variable names | Task
Describe, and give a pointer to documentation on your languages use of characters beyond those of the ASCII character set in the naming of variables.
Show how to:
Set a variable with a name including the 'Δ', (delta character), to 1
Increment it
Print its value.
Related task
Case-sensitivity of identifiers
| #Lua | Lua | ∆ = 1
∆ = ∆ + 1
print(∆) |
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #ERRE | ERRE | PROGRAM UNBIAS
FUNCTION RANDN(N)
RANDN=INT(1+N*RND(1))=1
END FUNCTION
PROCEDURE UNBIASED(N->RIS)
LOCAL A,B
REPEAT
A=RANDN(N)
B=RANDN(N)
UNTIL A<>B
RIS=A
END PROCEDURE
BEGIN
PRINT(CHR$(12);) ! CLS
RANDOMIZE(TIMER)
FOR N=3 TO 6 DO
BIASED=0
UNBIASED=0
FOR I=1 TO 10000 DO
IF RANDN(N) THEN biased+=1
UNBIASED(N->RIS)
IF RIS THEN unbiased+=+1
END FOR
PRINT("N =";N;" : biased =";biased/100;", unbiased =";unbiased/100)
END FOR
END PROGRAM
|
http://rosettacode.org/wiki/Unbias_a_random_generator | Unbias a random generator |
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
P
0
{\displaystyle P_{0}}
P
0
{\displaystyle P_{0}}
P
1
{\displaystyle P_{1}}
Task details
Use your language's random number generator to create a function/method/subroutine/... randN that returns a one or a zero, but with one occurring, on average, 1 out of N times, where N is an integer from the range 3 to 6 inclusive.
Create a function unbiased that uses only randN as its source of randomness to become an unbiased generator of random ones and zeroes.
For N over its range, generate and show counts of the outputs of randN and unbiased(randN).
The actual unbiasing should be done by generating two numbers at a time from randN and only returning a 1 or 0 if they are different. As long as you always return the first number or always return the second number, the probabilities discussed above should take over the biased probability of randN.
This task is an implementation of Von Neumann debiasing, first described in a 1951 paper.
| #Euphoria | Euphoria | function randN(integer N)
return rand(N) = 1
end function
function unbiased(integer N)
integer a
while 1 do
a = randN(N)
if a != randN(N) then
return a
end if
end while
end function
constant n = 10000
integer cb, cu
for b = 3 to 6 do
cb = 0
cu = 0
for i = 1 to n do
cb += randN(b)
cu += unbiased(b)
end for
printf(1, "%d: %5.2f%% %5.2f%%\n", {b, 100 * cb / n, 100 * cu / n})
end for |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
An untouchable are those numbers that are not in the image of the aliquot sum function. (From Wikipedia)
Untouchable numbers: impossible values for the sum of all aliquot parts function. (From OEIS: The On-line Encyclopedia of Integer Sequences®)
An untouchable number is a positive integer that is not the sum of the proper divisors of any number. (From MathWorld™)
Observations and conjectures
All untouchable numbers > 5 are composite numbers.
No untouchable number is perfect.
No untouchable number is sociable.
No untouchable number is a Mersenne prime.
No untouchable number is one more than a prime number, since if p is prime, then
the sum of the proper divisors of p2 is p + 1.
No untouchable number is three more than an odd prime number, since if p is an odd prime, then the
sum of the proper divisors of 2p is p + 3.
The number 5 is believed to be the only odd untouchable number, but this has not been proven: it would follow from a
slightly stronger version of the Goldbach's conjecture, since the sum of the
proper divisors of pq (with p, q being
distinct primes) is 1 + p + q.
There are infinitely many untouchable numbers, a fact that was proven
by Paul Erdős.
According to Chen & Zhao, their natural density is at least d > 0.06.
Task
show (in a grid format) all untouchable numbers ≤ 2,000.
show (for the above) the count of untouchable numbers.
show the count of untouchable numbers from unity up to (inclusive):
10
100
1,000
10,000
100,000
... or as high as is you think is practical.
all output is to be shown here, on this page.
See also
Wolfram MathWorld: untouchable number.
OEIS: A005114 untouchable numbers.
OEIS: a list of all untouchable numbers below 100,000 (inclusive).
Wikipedia: untouchable number.
Wikipedia: Goldbach's conjecture.
| #REXX | REXX | /*REXX pgm finds N untouchable numbers (numbers that can't be equal to any aliquot sum).*/
parse arg n cols tens over . /*obtain optional arguments from the CL*/
if n='' | n=="," then n=2000 /*Not specified? Then use the default.*/
if cols='' | cols=="," | cols==0 then cols= 10 /* " " " " " " */
if tens='' | tens=="," then tens= 0 /* " " " " " " */
if over='' | over=="," then over= 20 /* " " " " " " */
tell= n>0; n= abs(n) /*N>0? Then display the untouchable #s*/
call genP n * over /*call routine to generate some primes.*/
u.= 0 /*define all possible aliquot sums ≡ 0.*/
do p=1 for #; _= @.p + 1; u._= 1 /*any prime+1 is not an untouchable.*/
_= @.p + 3; u._= 1 /* " prime+3 " " " " */
end /*p*/ /* [↑] this will also rule out 5. */
u.5= 0 /*special case as prime 2 + 3 sum to 5.*/
do j=2 for lim; if !.j then iterate /*Is J a prime? Yes, then skip it. */
y= sigmaP() /*compute: aliquot sum (sigma P) of J.*/
if y<=n then u.y= 1 /*mark Y as a touchable if in range. */
end /*j*/
call show /*maybe show untouchable #s and a count*/
if tens>0 then call powers /*Any "tens" specified? Calculate 'em.*/
exit cnt /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
commas: parse arg ?; do jc=length(?)-3 to 1 by -3; ?=insert(',', ?, jc); end; return ?
genSq: do _=1 until _*_>lim; q._= _*_; end; q._= _*_; _= _+1; q._= _*_; return
grid: $= $ right( commas(t), w); if cnt//cols==0 then do; say $; $=; end; return
powers: do pr=1 for tens; call 'UNTOUCHA' -(10**pr); end /*recurse*/; return
/*──────────────────────────────────────────────────────────────────────────────────────*/
genP: #= 9; @.1=2; @.2=3; @.3=5; @.4=7; @.5=11; @.6=13; @.7=17; @.8=19; @.9=23 /*a list*/
!.=0; !.2=1; !.3=1; !.5=1; !.7=1; !.11=1; !.13=1; !.17=1; !.19=1 !.23=1 /*primes*/
parse arg lim; call genSq /*define the (high) limit for searching*/
qq.10= 100 /*define square of the 10th prime index*/
do j=@.#+6 by 2 to lim /*find odd primes from here on forward.*/
parse var j '' -1 _; if _==5 then iterate; if j// 3==0 then iterate
if j// 7==0 then iterate; if j//11==0 then iterate; if j//13==0 then iterate
if j//17==0 then iterate; if j//19==0 then iterate; if j//23==0 then iterate
/*start dividing by the tenth prime: 29*/
do k=10 while qq.k <= j /* [↓] divide J by known odd primes.*/
if j//@.k==0 then iterate j /*J ÷ by a prime? Then ¬prime. ___ */
end /*k*/ /* [↑] only process numbers ≤ √ J */
#= #+1; @.#= j /*bump prime count; assign a new prime.*/
!.j= 1; qq.#= j*j /*mark prime; compute square of prime.*/
end /*j*/; return /*#: is the number of primes generated*/
/*──────────────────────────────────────────────────────────────────────────────────────*/
show: w=7; $= right(2, w+1) right(5, w) /*start the list of an even prime and 5*/
cnt= 2 /*count of the only two primes in list.*/
do t=6 by 2 to n; if u.t then iterate /*Is T touchable? Then skip it. */
cnt= cnt + 1; if tell then call grid /*bump count; maybe show a grid line. */
end /*t*/
if tell & $\=='' then say $ /*display a residual grid line, if any.*/
if tell then say /*show a spacing blank line for output.*/
if n>0 then say right( commas(cnt), 20) , /*indent the output a bit.*/
' untouchable numbers were found ≤ ' commas(n); return
/*──────────────────────────────────────────────────────────────────────────────────────*/
sigmaP: s= 1 /*set initial sigma sum (S) to 1. ___*/
if j//2 then do m=3 by 2 while q.m<j /*divide by odd integers up to the √ J */
if j//m==0 then s=s+m+j%m /*add the two divisors to the sum. */
end /*m*/ /* [↑] process an odd integer. ___*/
else do m=2 while q.m<j /*divide by all integers up to the √ J */
if j//m==0 then s=s+m+j%m /*add the two divisors to the sum. */
end /*m*/ /* [↑] process an even integer. ___*/
if q.m==j then return s + m /*Was J a square? If so, add √ J */
return s /* No, just return. */ |
http://rosettacode.org/wiki/Two_bullet_roulette | Two bullet roulette | The following is supposedly a question given to mathematics graduates seeking jobs on Wall Street:
A revolver handgun has a revolving cylinder with six chambers for bullets.
It is loaded with the following procedure:
1. Check the first chamber to the right of the trigger for a bullet. If a bullet
is seen, the cylinder is rotated one chamber clockwise and the next chamber
checked until an empty chamber is found.
2. A cartridge containing a bullet is placed in the empty chamber.
3. The cylinder is then rotated one chamber clockwise.
To randomize the cylinder's position, the cylinder is spun, which causes the cylinder to take
a random position from 1 to 6 chamber rotations clockwise from its starting position.
When the trigger is pulled the gun will fire if there is a bullet in position 0, which is just
counterclockwise from the loading position.
The gun is unloaded by removing all cartridges from the cylinder.
According to the legend, a suicidal Russian imperial military officer plays a game of Russian
roulette by putting two bullets in a six-chamber cylinder and pulls the trigger twice.
If the gun fires with a trigger pull, this is considered a successful suicide.
The cylinder is always spun before the first shot, but it may or may not be spun after putting
in the first bullet and may or may not be spun after taking the first shot.
Which of the following situations produces the highest probability of suicide?
A. Spinning the cylinder after loading the first bullet, and spinning again after the first shot.
B. Spinning the cylinder after loading the first bullet only.
C. Spinning the cylinder after firing the first shot only.
D. Not spinning the cylinder either after loading the first bullet or after the first shot.
E. The probability is the same for all cases.
Task
Run a repeated simulation of each of the above scenario, calculating the percentage of suicide with a randomization of the four spinning, loading and firing order scenarios.
Show the results as a percentage of deaths for each type of scenario.
The hand calculated probabilities are 5/9, 7/12, 5/9, and 1/2. A correct program should produce results close enough to those to allow a correct response to the interview question.
Reference
Youtube video on the Russian 1895 Nagant revolver [[1]]
| #AutoHotkey | AutoHotkey | methods =
(
load, spin, load, spin, fire, spin, fire
load, spin, load, spin, fire, fire
load, load, spin, fire, spin, fire
load, load, spin, fire, fire
)
for i, method in StrSplit(methods, "`n", "`r"){
death := 0
main:
loop 100000 {
sixGun := []
for i, v in StrSplit(StrReplace(method," "), ",")
if %v%()
continue, main
}
output .= Format("{1:0.3f}", death/1000) "% Deaths for : """ method """`n"
}
MsgBox % output
return
load(){
global
if !sixGun.Count()
sixGun := [0,1,0,0,0,0]
else
if sixGun[2]
sixGun[1] := 1
sixGun[2] := 1
}
fire(){
global
if bullet := sixGun[1]
death++
temp := sixGun[6]
loop, 5
sixGun[7-A_Index] := sixGun[6-A_Index]
sixGun[1] := temp
return bullet
}
spin(){
global
Random, rnd, 1, 12
loop, % rnd {
temp := sixGun[6]
loop, 5
sixGun[7-A_Index] := sixGun[6-A_Index]
sixGun[1] := temp
}
} |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Jsish | Jsish | # help File.glob
File.glob(pattern:regexp|string|null='*', options:function|object|null=void):array
Return list of files in dir with optional pattern match.
With no arguments (or null) returns all files/directories in current directory.
The first argument can be a pattern (either a glob or regexp) of the files to return.
When the second argument is a function, it is called with each path, and filter on false.
Otherwise second argument must be a set of options. |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:
/foo/bar
/foo/bar/1
/foo/bar/2
/foo/bar/a
/foo/bar/b
When the program is executed in `/foo`, it should print:
bar
and when the program is executed in `/foo/bar`, it should print:
1
2
a
b
| #Julia | Julia | # v0.6.0
for e in readdir() # Current directory
println(e)
end
# Same for...
readdir("~") # Read home directory
readdir("~/documents") |
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