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http://rosettacode.org/wiki/Sleep | Sleep | Task
Write a program that does the following in this order:
Input an amount of time to sleep in whatever units are most natural for your language (milliseconds, seconds, ticks, etc.). This unit should be noted in comments or in a description.
Print "Sleeping..."
Sleep the main thread for the given amount of time.
Print "Awake!"
End.
Related task
Nautical bell
| #Zoomscript | Zoomscript | print "Sleeping..."
wait 1
println
print "Awake!" |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Standard_ML | Standard ML | open XWindows ;
open Motif ;
val countWindow = fn () =>
let
val ctr = ref 0;
val shell = XtAppInitialise "" "demo" "top" [] [XmNwidth 300, XmNheight 150 ] ;
val main = XmCreateMainWindow shell "main" [XmNmappedWhenManaged true ] ;
val frame = XmCreateForm main "frame" [XmNwidth 390, XmNheight 290 ] ;
val text = XmCreateLabel frame "show" [XmNlabelString "No clicks yet" ] ;
val buttn = XmCreateDrawnButton frame "press" [XmNwidth 75 , XmNheight 30 ,
XmNlabelString "Click me" ,
XmNbottomAttachment XmATTACH_POSITION,XmNbottomPosition 98 ] ;
val report = fn (w,c,t) =>
(XtSetValues text [XmNlabelString (Int.toString (ctr:= !ctr +1; !ctr)) ] ; t )
in
(
XtSetCallbacks buttn [ (XmNactivateCallback , report) ] XmNarmCallback ;
XtManageChildren [ text,buttn ] ;
XtManageChildren [ frame ] ;
XtManageChild main ;
XtRealizeWidget shell
)
end;
|
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Tcl | Tcl | package require Tk
pack [label .l -text "There have been no clicks yet"]
set count 0
pack [button .b -text "click me" -command upd]
proc upd {} {
.l configure -text "Number of clicks: [incr ::count]"
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #C.23 | C# | using System;
class Program
{
static void Main()
{
Console.WriteLine(new DateTime());
}
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #C.2B.2B | C++ | #include <iostream>
#include <chrono>
#include <ctime>
int main()
{
std::chrono::system_clock::time_point epoch;
std::time_t t = std::chrono::system_clock::to_time_t(epoch);
std::cout << std::asctime(std::gmtime(&t)) << '\n';
return 0;
} |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Nim | Nim | import math
import imageman
const
Red = ColorRGBU [byte 255, 0, 0]
Green = ColorRGBU [byte 0, 255, 0]
Blue = ColorRGBU [byte 0, 0, 255]
Magenta = ColorRGBU [byte 255, 0, 255]
Cyan = ColorRGBU [byte 0, 255, 255]
Black = ColorRGBU [byte 0, 0, 0]
(W, H) = (640, 640)
Deg72 = degToRad(72.0)
ScaleFactor = 1 / ( 2 + cos(Deg72) * 2)
Palette = [Red, Green, Blue, Magenta, Cyan]
proc drawPentagon(img: var Image; x, y, side: float; depth: int) =
var (x, y) = (x, y)
var colorIndex {.global.} = 0
var angle = 3 * Deg72
if depth == 0:
for _ in 0..4:
let (prevx, prevy) = (x, y)
x += cos(angle) * side
y -= sin(angle) * side
img.drawLine(prevx.toInt, prevy.toInt, x.toInt, y.toInt, Palette[colorIndex])
angle += Deg72
colorIndex = (colorIndex + 1) mod 5
else:
let side = side * ScaleFactor
let dist = side * (1 + cos(Deg72) * 2)
for _ in 0..4:
x += cos(angle) * dist
y -= sin(angle) * dist
img.drawPentagon(x, y, side, depth - 1)
angle += Deg72
var image = initImage[ColorRGBU](W, H)
image.fill(Black)
var order = 5
let hw = W / 2
let margin = 20.0
let radius = hw - 2 * margin
let side = radius * sin(PI / 5) * 2
image.drawPentagon(hw, 3 * margin, side, order - 1)
image.savePNG("Sierpinski_pentagon.png", compression = 9) |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Perl | Perl | use ntheory qw(todigits);
use Math::Complex;
$sides = 5;
$order = 5;
$dim = 250;
$scale = ( 3 - 5**.5 ) / 2;
push @orders, ((1 - $scale) * $dim) * $scale ** $_ for 0..$order-1;
open $fh, '>', 'sierpinski_pentagon.svg';
print $fh qq|<svg height="@{[$dim*2]}" width="@{[$dim*2]}" style="fill:blue" version="1.1" xmlns="http://www.w3.org/2000/svg">\n|;
$tau = 2 * 4*atan2(1, 1);
push @vertices, cis( $_ * $tau / $sides ) for 0..$sides-1;
for $i (0 .. -1+$sides**$order) {
@base5 = todigits($i,5);
@i = ( ((0)x(-1+$sides-$#base5) ), @base5);
@v = @vertices[@i];
$vector = 0;
$vector += $v[$_] * $orders[$_] for 0..$#orders;
my @points;
for (@vertices) {
$v = $vector + $orders[-1] * (1 - $scale) * $_;
push @points, sprintf '%.3f %.3f', $v->Re, $v->Im;
}
print $fh pgon(@points);
}
sub cis { Math::Complex->make(cos($_[0]), sin($_[0])) }
sub pgon { my(@q)=@_; qq|<polygon points="@q" transform="translate($dim,$dim) rotate(-18)"/>\n| }
print $fh '</svg>';
close $fh; |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #C.23 | C# | using System;
using System.Collections;
namespace RosettaCode {
class SierpinskiTriangle {
int len;
BitArray b;
public SierpinskiTriangle(int n) {
if (n < 1) {
throw new ArgumentOutOfRangeException("Order must be greater than zero");
}
len = 1 << (n+1);
b = new BitArray(len+1, false);
b[len>>1] = true;
}
public void Display() {
for (int j = 0; j < len / 2; j++) {
for (int i = 0; i < b.Count; i++) {
Console.Write("{0}", b[i] ? "*" : " ");
}
Console.WriteLine();
NextGen();
}
}
private void NextGen() {
BitArray next = new BitArray(b.Count, false);
for (int i = 0; i < b.Count; i++) {
if (b[i]) {
next[i - 1] = next[i - 1] ^ true;
next[i + 1] = next[i + 1] ^ true;
}
}
b = next;
}
}
} |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | Sierpinski[n_] :=
Nest[Join @@ Table[With[{a = #[[i, 1]], b = #[[i, 2]], c = #[[i, 3]]},
{{a, (a + b)/2, (c + a)/2}, {(a + b)/2, b, (b + c)/2}, {(c + a)/2, (b + c)/2, c}}],
{i, Length[#]}] &, {{{0, 0}, {1/2, 1}, {1, 0}}}, n]
Graphics[{Black, Polygon /@ Sierpinski[8]}] |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #MATLAB | MATLAB | [x, x0] = deal(cat(3, [1 0]', [-1 0]', [0 sqrt(3)]'));
for k = 1 : 6
x = x(:,:) + x0 * 2 ^ k / 2;
end
patch('Faces', reshape(1 : 3 * 3 ^ k, 3, '')', 'Vertices', x(:,:)') |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #TI-89_BASIC | TI-89 BASIC | Prgm
Local clicks
0 → clicks
1 → ok © System variable also set by Dialog statement
While ok = 1
Dialog
Title "Rosetta Code"
Text "There have been " & string(clicks) & " OKs"
EndDlog
clicks + 1 → clicks
EndWhile
EndPrgm |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Unicon | Unicon |
import gui
$include "guih.icn"
class SimpleApp : Dialog (label)
# -- automatically called when the dialog is created
method component_setup()
# create and add the label
label := Label("label=There have been no clicks yet","pos=50%,33%", "align=c,c")
add (label)
# create and add the button
button := TextButton("label=Click me", "pos=50%,66%", "align=c,c")
button.connect(self, "clicked", ACTION_EVENT)
add (button)
# some cosmetic settings for the window
attrib("size=180,70", "bg=light gray")
end
method clicked ()
static count := 0
count +:= 1
label.set_label ("Clicked " || count || " times")
end
end
procedure main()
local d := SimpleApp ()
d.show_modal()
end
|
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Clojure | Clojure | (println (java.util.Date. 0)) |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #COBOL | COBOL | IDENTIFICATION DIVISION.
PROGRAM-ID. epoch.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 epoch-date.
03 year PIC 9(4).
03 month PIC 99.
03 dday PIC 99.
PROCEDURE DIVISION.
MOVE FUNCTION DATE-OF-INTEGER(1) TO epoch-date
DISPLAY year "-" month "-" dday
GOBACK
. |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Phix | Phix | --
-- demo\rosetta\SierpinskyPentagon.exw
-- ===================================
--
with javascript_semantics
include pGUI.e
Ihandle dlg, canvas
cdCanvas cddbuffer
constant title = "Sierpinski Pentagon",
scale_factor = 1/(2+cos(2*PI/5)*2),
side_factor = 1+cos(2*PI/5)*2,
angles = sq_mul(2*PI/5,tagset(7,3)),
cosangles = apply(angles,cos),
sinangles = apply(angles,sin)
integer level = 3
procedure drawPentagon(atom x, y, side, w, h, integer depth)
if depth=0 then
cdCanvasBegin(cddbuffer,CD_FILL)
for i=1 to 5 do
x += cosangles[i] * side
y -= sinangles[i] * side
cdCanvasVertex(cddbuffer, w+x, h-y)
end for
cdCanvasEnd(cddbuffer)
else
side *= scale_factor
atom distance = side*side_factor
for i=1 to 5 do
x += cosangles[i] * distance
y -= sinangles[i] * distance
drawPentagon(x, y, side, w, h, depth-1)
end for
end if
end procedure
function redraw_cb(Ihandle /*ih*/, integer /*posx*/, /*posy*/)
integer {w, h} = IupGetIntInt(canvas, "DRAWSIZE")
atom hw = min(w/2,h/2),
margin = 20,
radius = hw - 2*margin,
side = radius * sin(PI/5) * 2
cdCanvasActivate(cddbuffer)
cdCanvasClear(cddbuffer)
drawPentagon(hw, 3*margin, side, w/2-radius-2*margin, h, level)
cdCanvasFlush(cddbuffer)
return IUP_DEFAULT
end function
function map_cb(Ihandle ih)
cdCanvas cdcanvas = cdCreateCanvas(CD_IUP, ih)
cddbuffer = cdCreateCanvas(CD_DBUFFER, cdcanvas)
cdCanvasSetBackground(cddbuffer, CD_PARCHMENT)
cdCanvasSetForeground(cddbuffer, CD_BLUE)
return IUP_DEFAULT
end function
procedure set_dlg_title()
IupSetStrAttribute(dlg, "TITLE", "%s (level %d)",{title,level})
end procedure
function key_cb(Ihandle /*ih*/, atom c)
if c=K_ESC then return IUP_CLOSE end if
if find(c,"+-") then
if c='+' then
level = min(5,level+1)
elsif c='-' then
level = max(0,level-1)
end if
set_dlg_title()
IupRedraw(canvas)
end if
return IUP_CONTINUE
end function
procedure main()
IupOpen()
canvas = IupCanvas("RASTERSIZE=640x640")
IupSetCallbacks(canvas, {"MAP_CB", Icallback("map_cb"),
"ACTION", Icallback("redraw_cb")})
dlg = IupDialog(canvas)
IupSetCallback(dlg, "KEY_CB", Icallback("key_cb"))
set_dlg_title()
IupShow(dlg)
IupSetAttribute(canvas, "RASTERSIZE", NULL)
if platform()!=JS then
IupMainLoop()
IupClose()
end if
end procedure
main()
|
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #C.2B.2B | C++ | #include <iostream>
#include <string>
#include <list>
#include <algorithm>
#include <iterator>
using namespace std;
template<typename OutIt>
void sierpinski(int n, OutIt result)
{
if( n == 0 )
{
*result++ = "*";
}
else
{
list<string> prev;
sierpinski(n-1, back_inserter(prev));
string sp(1 << (n-1), ' ');
result = transform(prev.begin(), prev.end(),
result,
[sp](const string& x) { return sp + x + sp; });
transform(prev.begin(), prev.end(),
result,
[sp](const string& x) { return x + " " + x; });
}
}
int main()
{
sierpinski(4, ostream_iterator<string>(cout, "\n"));
return 0;
} |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Nim | Nim | import imageman
const
Black = ColorRGBU [byte 0, 0, 0] # For background.
Red = ColorRGBU [byte 255, 0, 0] # For triangle.
proc drawSierpinski(img: var Image; txy: array[1..6, float]; levelsYet: Natural) =
var nxy: array[1..6, float]
if levelsYet > 0:
for i in 1..6:
let pos = if i < 5: i + 2 else: i - 4
nxy[i] = (txy[i] + txy[pos]) / 2
img.drawSierpinski([txy[1], txy[2], nxy[1], nxy[2], nxy[5], nxy[6]], levelsYet - 1)
img.drawSierpinski([nxy[1], nxy[2], txy[3], txy[4], nxy[3], nxy[4]], levelsyet - 1)
img.drawSierpinski([nxy[5], nxy[6], nxy[3], nxy[4], txy[5], txy[6]], levelsyet - 1)
else:
img.drawPolyline(closed = true, Red,
(txy[1].toInt, txy[2].toInt), (txy[3].toInt, txy[4].toInt),(txy[5].toInt, txy[6].toInt))
var image = initImage[ColorRGBU](800, 800)
image.fill(Black)
image.drawSierpinski([400.0, 100.0, 700.0, 500.0, 100.0, 500.0], 7)
image.savePNG("sierpinski_triangle.png", compression = 9) |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Objeck | Objeck | use Game.SDL2;
use Game.Framework;
class Test {
@framework : GameFramework;
@colors : Color[];
@step : Int;
function : Main(args : String[]) ~ Nil {
Test->New()->Run();
}
New() {
@framework := GameFramework->New(GameConsts->SCREEN_WIDTH, GameConsts->SCREEN_HEIGHT, "Sierpinski Triangle");
@framework->SetClearColor(Color->New(0,0,0));
@colors := Color->New[1];
@colors[0] := Color->New(178,34,34);
}
method : Run() ~ Nil {
if(@framework->IsOk()) {
e := @framework->GetEvent();
quit := false;
while(<>quit) {
# process input
while(e->Poll() <> 0) {
if(e->GetType() = EventType->SDL_QUIT) {
quit := true;
};
};
@framework->FrameStart();
@framework->Clear();
Render(8, 20, 20, 450);
@framework->Show();
@framework->FrameEnd();
};
}
else {
"--- Error Initializing Environment ---"->ErrorLine();
return;
};
leaving {
@framework->Quit();
};
}
method : Render(level : Int, x : Int, y : Int, size : Int) ~ Nil {
if(level > -1) {
renderer := @framework->GetRenderer();
renderer->LineColor(x, y, x+size, y, @colors[0]);
renderer->LineColor(x, y, x, y+size, @colors[0]);
renderer->LineColor(x+size, y, x, y+size, @colors[0]);
Render(level-1, x, y, size/2);
Render(level-1, x+size/2, y, size/2);
Render(level-1, x, y+size/2, size/2);
};
}
}
consts GameConsts {
SCREEN_WIDTH := 640,
SCREEN_HEIGHT := 480
}
|
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Vedit_macro_language | Vedit macro language | Reg_Set(10, "There have been no clicks yet")
#1 = 0
repeat (ALL) {
#2 = Dialog_Input_1(3, "`Simple Windowed Application`,
`|@(10)`,
`[&Click me]`,`[&Exit]`",
APP+CENTER, 0, 0)
if (#2 != 1) { break } // ESC or Exit
#1++
Num_Str(#1, 10)
Reg_Set(10, "Clicked", INSERT)
Reg_Set(10, " times", APPEND)
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #CoffeeScript | CoffeeScript | console.log new Date(0).toISOString() |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Common_Lisp | Common Lisp | (multiple-value-bind (second minute hour day month year) (decode-universal-time 0 0)
(format t "~4,'0D-~2,'0D-~2,'0D ~2,'0D:~2,'0D:~2,'0D" year month day hour minute second)) |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #D | D | main() {
print(new Date.fromEpoch(0,new TimeZone.utc()));
} |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Processing | Processing |
float s_angle, scale, margin = 25, total = 4;
float p_size = 700;
float radius = p_size/2-2*margin;
float side = radius * sin(PI/5)*2;
void setup() {
float temp = width/2;
size(590, 590);
background(0, 0, 200);
stroke(255);
s_angle = 72*PI/180;
scale = 1/(2+cos(s_angle)*2);
for (int i = 0; i < total; i++) {
background(0, 0, 200);
drawPentagon(width/2, (height-p_size)/2 + 3*margin, side, total);
}
}
void drawPentagon(float x, float y, float side, float depth) {
float angle = 3*s_angle;
if (depth == 0) {
for (int i = 0; i < 5; i++) {
float px = x;
float py = y;
x = x+cos(angle)*side;
y = y-sin(angle)*side;
line(x, y, px, py);
angle += s_angle;
}
} else {
side *= scale;
float distance = side+side*cos(s_angle)*2;
for (int j = 0; j < 5; j++) {
x = x+cos(angle)*distance;
y = y-sin(angle)*distance;
drawPentagon(x, y, side, depth-1);
angle += s_angle;
}
}
} |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #Clojure | Clojure | (ns example
(:require [clojure.contrib.math :as math]))
; Length of integer in binary
; (copied from a private multimethod in clojure.contrib.math)
(defmulti #^{:private true} integer-length class)
(defmethod integer-length java.lang.Integer [n]
(count (Integer/toBinaryString n)))
(defmethod integer-length java.lang.Long [n]
(count (Long/toBinaryString n)))
(defmethod integer-length java.math.BigInteger [n]
(count (.toString n 2)))
(defn sierpinski-triangle [order]
(loop [size (math/expt 2 order)
v (math/expt 2 (- size 1))]
(when (pos? size)
(println
(apply str (map #(if (bit-test v %) "*" " ")
(range (integer-length v)))))
(recur
(dec size)
(bit-xor (bit-shift-left v 1) (bit-shift-right v 1))))))
(sierpinski-triangle 4) |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #OCaml | OCaml | open Graphics
let round v =
int_of_float (floor (v +. 0.5))
let middle (x1, y1) (x2, y2) =
((x1 +. x2) /. 2.0,
(y1 +. y2) /. 2.0)
let draw_line (x1, y1) (x2, y2) =
moveto (round x1) (round y1);
lineto (round x2) (round y2);
;;
let draw_triangle (p1, p2, p3) =
draw_line p1 p2;
draw_line p2 p3;
draw_line p3 p1;
;;
let () =
open_graph "";
let width = float (size_x ()) in
let height = float (size_y ()) in
let pad = 20.0 in
let initial_triangle =
( (pad, pad),
(width -. pad, pad),
(width /. 2.0, height -. pad) )
in
let rec loop step tris =
if step <= 0 then tris else
loop (pred step) (
List.fold_left (fun acc (p1, p2, p3) ->
let m1 = middle p1 p2
and m2 = middle p2 p3
and m3 = middle p3 p1 in
let tri1 = (p1, m1, m3)
and tri2 = (p2, m2, m1)
and tri3 = (p3, m3, m2) in
tri1 :: tri2 :: tri3 :: acc
) [] tris
)
in
let res = loop 6 [ initial_triangle ] in
List.iter draw_triangle res;
ignore (read_key ()) |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #11l | 11l | T Item
String name, date, category
F (name, date, category)
.name = name
.date = date
.category = category
F String()
R .name‘, ’(.date)‘, ’(.category)
V db_filename = ‘simdb.csv’
F load()
[Item] db
L(line) File(:db_filename).read().rtrim("\n").split("\n")
V item = line.split(‘, ’)
db.append(Item(item[0], item[1], item[2]))
R db
F store(item)
File(:db_filename, ‘a’).write(String(item)"\n")
F printUsage()
print(|‘
Usage:
simdb cmd [categoryName]
add add item, followed by optional category
latest print last added item(s), followed by optional category
all print all
For instance: add "some item name" "some category name’)
F addItem(args)
I args.len < 2
printUsage()
R
V date = Time().strftime(‘%Y-%m-%d %H:%M:%S’)
V cat = I args.len == 3 {args[2]} E ‘none’
store(Item(args[1], date, cat))
F printLatest(a)
V db = load()
I db.empty
print(‘No entries in database.’)
R
I a.len == 2
L(item) reversed(db)
I item.category == a[1]
print(item)
L.break
L.was_no_break
print(‘There are no items for category '’a[1]‘'’)
E
print(db.last)
F printAll()
V db = load()
I db.empty
print(‘No entries in database.’)
R
L(item) db
print(item)
:start:
I :argv.len C 2..4
S :argv[1].lowercase()
‘add’
addItem(:argv[1..])
‘latest’
printLatest(:argv[1..])
‘all’
printAll()
E
printUsage()
E
printUsage() |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #11l | 11l | F scs(String x, y)
I x.empty
R y
I y.empty
R x
I x[0] == y[0]
R x[0]‘’scs(x[1..], y[1..])
I scs(x, y[1..]).len <= scs(x[1..], y).len
R y[0]‘’scs(x, y[1..])
E
R x[0]‘’scs(x[1..], y)
print(scs(‘abcbdab’, ‘bdcaba’)) |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Visual_Basic | Visual Basic | VERSION 5.00
Begin VB.Form Form2
Caption = "There have been no clicks yet"
ClientHeight = 2940
ClientLeft = 60
ClientTop = 600
ClientWidth = 8340
LinkTopic = "Form1"
ScaleHeight = 2940
ScaleWidth = 8340
StartUpPosition = 3 'Windows Default
Begin VB.CommandButton Command1
Caption = "Click me!"
Height = 495
Left = 3600
TabIndex = 0
Top = 1200
Width = 1215
End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
'-----user-written code begins here; everything above this line is hidden in the GUI-----
Private clicked As Long
Private Sub Command1_Click()
clicked = clicked + 1
Me.Caption = clicked & " clicks."
End Sub
|
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Web_68 | Web 68 | @1Introduction.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public Licence as published by
the Free Software Foundation, either version 3 of the Licence, or
(at your option) any later version.
Copyright (c) 2012 Sian Mountbatten.
@m cvs simpleapp = "$Id: $"
@a@<Prelude@>
BEGIN
@<Included declarations@>
@<Plain values in the outer reach@>
@<Names in the outer reach@>
@<Procedures in the outer reach@>
@<Logic in the outer reach@>
END
@<Postlude@>
@ The local compiler requires a special prelude.@^system dependencies@>
@<Prel...@>=
PROGRAM simpleapp CONTEXT VOID
USE @<Library preludes@>
@ And a special postlude.@^system dependencies@>
@<Post...@>=
FINISH
@ The program requires the predefined forms and the standard prelude.
@<Library...@>=
simpleapp fd,standard
@ This Web 68 file provides the Xforms prelude.
@iforms.w@>
@1Initialisation.
The initial processing consists of initialising the Xforms library.
@<Logic...@>=
open(argf,"",arg channel);
fl initialize(argc,argv,"simpleapp",NIL,0);
@ Declare the !REF FILE!.
@<Names...@>=
FILE @!argf;
@1Main processing.
The form is created in !simpleapp fd! the source code of which is 108 lines long.
Firstly, define the callback for the button.
@<Proc...@>=
button cb:=(REF FLOBJECT obj,INT data)VOID:
(
clicks +:= 1;
fl set object label(text box OF click form,whole(clicks,0)+" click"+
(clicks=1|""|"s")+" on the button")
);
@ Declare !clicks!.
@<Plain...@>=
INT clicks:=0;
@ Create the form, show it and hand control to the Xforms library.
@<Logic...@>=
click form:=create form click;
fl show form(click OF click form,fl place center,fl full border,"SimpleApp");
fl do forms
@ Declare the form.
@<Names...@>=
REF FDCLICK click form;
@1Macro declarations.
All the macros used in the program are declared here.
@<Include...@>=
macro fl do forms;
macro fl initialize;
macro fl set object label;
macro fl show form;
@ To compile the program, use this command:
<pre>
ca -l mod -l forms simpleapp.w68
</pre>
The predefined form will have been compiled with this command:
<pre>
ca -m mod simpleappfd.w68
</pre>
The predefined form was created by the <b>fdesign</b> program for the Xforms library,
and the resulting form definition file was converted to Web 68 by the program
<b>fdtow68</b>. |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Dart | Dart | main() {
print(new Date.fromEpoch(0,new TimeZone.utc()));
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Delphi | Delphi | program ShowEpoch;
{$APPTYPE CONSOLE}
uses SysUtils;
begin
Writeln(FormatDateTime('yyyy-mm-dd hh:nn:ss.zzz', 0));
end. |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Erlang | Erlang | 2> calendar:universal_time().
{{2013,9,13},{8,3,16}}
3> calendar:datetime_to_gregorian_seconds(calendar:universal_time()).
63546278932
4> calendar:gregorian_seconds_to_datetime(63546278932).
{{2013,9,13},{8,8,52}}
11> calendar:gregorian_seconds_to_datetime(0).
{{0,1,1},{0,0,0}}
|
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Prolog | Prolog | main:-
write_sierpinski_pentagon('sierpinski_pentagon.svg', 600, 5).
write_sierpinski_pentagon(File, Size, Order):-
open(File, write, Stream),
format(Stream, "<svg xmlns='http://www.w3.org/2000/svg' width='~d' height='~d'>\n",
[Size, Size]),
write(Stream, "<rect width='100%' height='100%' fill='white'/>\n"),
Margin = 5,
Radius is Size/2 - 2 * Margin,
Side is Radius * sin(pi/5) * 2,
Height is Side * (sin(pi/5) + sin(2 * pi/5)),
X is Size/2,
Y is (Size - Height)/2,
Scale_factor is 1/(2 + cos(2 * pi/5) * 2),
sierpinski_pentagon(Stream, X, Y, Scale_factor, Side, Order),
write(Stream, "</svg>\n"),
close(Stream).
sierpinski_pentagon(Stream, X, Y, _, Side, 1):-
!,
write(Stream, "<polygon stroke-width='1' stroke='black' fill='blue' points='"),
format(Stream, '~g,~g', [X, Y]),
Angle is 6 * pi/5,
write_pentagon_points(Stream, Side, Angle, X, Y, 5),
write(Stream, "'/>\n").
sierpinski_pentagon(Stream, X, Y, Scale_factor, Side, N):-
Side1 is Side * Scale_factor,
N1 is N - 1,
Angle is 6 * pi/5,
sierpinski_pentagons(Stream, X, Y, Scale_factor, Side1, Angle, N1, 5).
write_pentagon_points(_, _, _, _, _, 0):-!.
write_pentagon_points(Stream, Side, Angle, X, Y, N):-
N1 is N - 1,
X1 is X + cos(Angle) * Side,
Y1 is Y - sin(Angle) * Side,
Angle1 is Angle + 2 * pi/5,
format(Stream, ' ~g,~g', [X1, Y1]),
write_pentagon_points(Stream, Side, Angle1, X1, Y1, N1).
sierpinski_pentagons(_, _, _, _, _, _, _, 0):-!.
sierpinski_pentagons(Stream, X, Y, Scale_factor, Side, Angle, N, I):-
I1 is I - 1,
Distance is Side + Side * cos(2 * pi/5) * 2,
X1 is X + cos(Angle) * Distance,
Y1 is Y - sin(Angle) * Distance,
Angle1 is Angle + 2 * pi/5,
sierpinski_pentagon(Stream, X1, Y1, Scale_factor, Side, N),
sierpinski_pentagons(Stream, X1, Y1, Scale_factor, Side, Angle1, N, I1). |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #CLU | CLU | sierpinski = proc (size: int) returns (string)
ss: stream := stream$create_output()
for i: int in int$from_to(0, size*4-1) do
c: int := 1
for j: int in int$from_to(1, size*4-1-i) do
stream$putc(ss, ' ')
end
for k: int in int$from_to(0, i) do
if c//2=0 then
stream$puts(ss, " ")
else
stream$puts(ss, " *")
end
c := c*(i-k)/(k+1)
end
stream$putc(ss, '\n')
end
return(stream$get_contents(ss))
end sierpinski
start_up = proc ()
stream$puts(
stream$primary_output(),
sierpinski(4)
)
end start_up |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #PARI.2FGP | PARI/GP |
\\ Sierpinski triangle fractal
\\ Note: plotmat() can be found here on
\\ http://rosettacode.org/wiki/Brownian_tree#PARI.2FGP page.
\\ 6/3/16 aev
pSierpinskiT(n)={
my(sz=2^n,M=matrix(sz,sz),x,y);
for(y=1,sz, for(x=1,sz, if(!bitand(x,y),M[x,y]=1);));\\fends
plotmat(M);
}
{\\ Test:
pSierpinskiT(9); \\ SierpT9.png
}
|
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #Bracmat | Bracmat | whl
' ( arg$:?command
& ( get'db
| (db=1)&lst$(db,db,NEW)
)
& !command
: ( add
& :?name:?tag:?date
& whl
' ( arg$:?argmnt
& arg$:?value
& (!argmnt.!value)
: ( (title|name.?name)
| (category|tag.?tag)
| (date.?date)
)
)
& ( !name:~
& !tag:~
& !date:~
& ( !db:?*!tag^(?+(!date.!name)+?)*?
& out$"This record already exists"
| !tag^(!date.!name)*!db:?db
& lst$(db,db,NEW)
)
| out$"invalid data"
)
| latest
& :?date
& nothing found:?latest
& ( !db
: ?
* ?tag
^ ( ?
+ ( (>!date:?date.?name)
& (!name,!tag,!date):?latest
& ~
)
+ ?
)
* ?
| out$!latest
)
| latest/category
& :?date:?latests:?latest
& ( !db
: ?
* ( ?tag
& !latests !latest:?latests
& :?latest:?date
)
^ ( ?
+ ( (>!date:?date.?name)
& (!name,!tag,!date):?latest
& ~
)
+ ?
)
* ?
| !latests !latest:?latests&out$!latests
)
| sorted
& 0:?sorted
& ( !db
: ?
* ?tag
^ ( ?
+ ( (?date.?name)
& (!date.!name,!tag,!date)+!sorted:?sorted
& ~
)
+ ?
)
* ?
| whl
' (!sorted:(?.?row)+?sorted&out$!row)
)
)
);
|
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #Ada | Ada | with Ada.Text_IO;
procedure Shortest is
function Scs (Left, Right : in String) return String is
Left_Tail : String renames Left (Left'First + 1 .. Left'Last);
Right_Tail : String renames Right (Right'First + 1 .. Right'Last);
begin
if Left = "" then return Right; end if;
if Right = "" then return Left; end if;
if Left (Left'First) = Right (Right'First) then
return Left (Left'First) & Scs (Left_Tail, Right_Tail);
end if;
declare
S1 : constant String := Scs (Left, Right_Tail);
S2 : constant String := Scs (Left_Tail, Right);
begin
return (if S1'Length <= S2'Length
then Right (Right'First) & S1
else Left (Left'First) & S2);
end;
end Scs;
procedure Exercise (Left, Right : String) is
use Ada.Text_Io;
begin
Put ("scs ( "); Put (Left); Put (" , "); Put (Right); Put ( " ) -> ");
Put (Scs (Left, Right));
New_Line;
end Exercise;
begin
Exercise ("abcbdab", "bdcaba");
Exercise ("WEASELS", "WARDANCE");
end Shortest; |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #ALGOL_68 | ALGOL 68 | BEGIN
PRIO SCS = 1;
# returns the shortest common supersequence of x and y #
OP SCS = ( STRING x, y )STRING:
IF x = "" THEN y
ELIF y = "" THEN x
ELIF x[ LWB x ] = y[ LWB y ]
THEN x[ LWB x ] + ( x[ LWB x + 1 : ] SCS y[ LWB y + 1 : ] )
ELIF STRING x y sub = x SCS y[ LWB y + 1 : ];
STRING x sub y = x[ LWB x + 1 : ] SCS y;
INT x y sub size = ( UPB x y sub - LWB x y sub ) + 1;
INT x sub y size = ( UPB x sub y - LWB x sub y ) + 1;
x y sub size <= x sub y size
THEN y[ LWB y ] + x y sub
ELSE x[ LWB x ] + x sub y
FI # SCS # ;
print( ( "abcbdab" SCS "bdcaba", newline ) )
END |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Wren | Wren | import "graphics" for Canvas, Color
import "input" for Mouse
import "dome" for Window
class SimpleWindowedApplication {
construct new(width, height) {
Window.title = "Simple windowed application"
_fore = Color.white
_clicks = 0
}
init() {
drawControls()
}
update() {
if (Mouse["left"].justPressed && insideButton) _clicks = _clicks + 1
}
draw(alpha) {
drawControls()
}
insideButton {
var p = Mouse.position
return p.x >= 120 && p.x <= 200 && p.y >= 90 && p.y <= 170
}
drawControls() {
Canvas.cls()
if (_clicks == 0) {
Canvas.print("There have been no clicks yet", 40, 40, _fore)
} else if (_clicks == 1) {
Canvas.print("The button has been clicked once", 30, 40, _fore)
} else {
Canvas.print("The button has been clicked %(_clicks) times", 10, 40, _fore)
}
Canvas.rectfill(120, 90, 80, 80, Color.red)
Canvas.rect(120, 90, 80, 80, Color.blue)
Canvas.print("click me", 130, 125, _fore)
}
}
var Game = SimpleWindowedApplication.new(600, 600) |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #F.23 | F# | printfn "%s" ((new System.DateTime()).ToString("u")) |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Factor | Factor | USING: calendar calendar.format io ;
0 micros>timestamp timestamp>ymdhms print |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Forth | Forth | include lib/longjday.4th
0 posix>jday .longjday cr |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Python | Python | from turtle import *
import math
speed(0) # 0 is the fastest speed. Otherwise, 1 (slow) to 10 (fast)
hideturtle() # hide the default turtle
part_ratio = 2 * math.cos(math.radians(72))
side_ratio = 1 / (part_ratio + 2)
hide_turtles = True # show/hide turtles as they draw
path_color = "black" # path color
fill_color = "black" # fill color
# turtle, size
def pentagon(t, s):
t.color(path_color, fill_color)
t.pendown()
t.right(36)
t.begin_fill()
for i in range(5):
t.forward(s)
t.right(72)
t.end_fill()
# iteration, turtle, size
def sierpinski(i, t, s):
t.setheading(0)
new_size = s * side_ratio
if i > 1:
i -= 1
# create four more turtles
for j in range(4):
t.right(36)
short = s * side_ratio / part_ratio
dist = [short, s, s, short][j]
# spawn a turtle
spawn = Turtle()
if hide_turtles:spawn.hideturtle()
spawn.penup()
spawn.setposition(t.position())
spawn.setheading(t.heading())
spawn.forward(dist)
# recurse for spawned turtles
sierpinski(i, spawn, new_size)
# recurse for parent turtle
sierpinski(i, t, new_size)
else:
# draw a pentagon
pentagon(t, s)
# delete turtle
del t
def main():
t = Turtle()
t.hideturtle()
t.penup()
screen = t.getscreen()
y = screen.window_height()
t.goto(0, y/2-20)
i = 5 # depth. i >= 1
size = 300 # side length
# so the spawned turtles move only the distance to an inner pentagon
size *= part_ratio
# begin recursion
sierpinski(i, t, size)
main() |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #COBOL | COBOL | identification division.
program-id. sierpinski-triangle-program.
data division.
working-storage section.
01 sierpinski.
05 n pic 99.
05 i pic 999.
05 k pic 999.
05 m pic 999.
05 c pic 9(18).
05 i-limit pic 999.
05 q pic 9(18).
05 r pic 9.
procedure division.
control-paragraph.
move 4 to n.
multiply n by 4 giving i-limit.
subtract 1 from i-limit.
perform sierpinski-paragraph
varying i from 0 by 1 until i is greater than i-limit.
stop run.
sierpinski-paragraph.
subtract i from i-limit giving m.
multiply m by 2 giving m.
perform m times,
display space with no advancing,
end-perform.
move 1 to c.
perform inner-loop-paragraph
varying k from 0 by 1 until k is greater than i.
display ''.
inner-loop-paragraph.
divide c by 2 giving q remainder r.
if r is equal to zero then display ' * ' with no advancing.
if r is not equal to zero then display ' ' with no advancing.
compute c = c * (i - k) / (k + 1). |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Perl | Perl | my $levels = 6;
my $side = 512;
my $height = get_height($side);
sub get_height { my($side) = @_; $side * sqrt(3) / 2 }
sub triangle {
my($x1, $y1, $x2, $y2, $x3, $y3, $fill, $animate) = @_;
my $svg;
$svg .= qq{<polygon points="$x1,$y1 $x2,$y2 $x3,$y3"};
$svg .= qq{ style="fill: $fill; stroke-width: 0;"} if $fill;
$svg .= $animate
? qq{>\n <animate attributeType="CSS" attributeName="opacity"\n values="1;0;1" keyTimes="0;.5;1" dur="20s" repeatCount="indefinite" />\n</polygon>\n}
: ' />';
return $svg;
}
sub fractal {
my( $x1, $y1, $x2, $y2, $x3, $y3, $r ) = @_;
my $svg;
$svg .= triangle( $x1, $y1, $x2, $y2, $x3, $y3 );
return $svg unless --$r;
my $side = abs($x3 - $x2) / 2;
my $height = get_height($side);
$svg .= fractal( $x1, $y1-$height*2, $x1-$side/2, $y1-3*$height, $x1+$side/2, $y1-3*$height, $r);
$svg .= fractal( $x2, $y1, $x2-$side/2, $y1-$height, $x2+$side/2, $y1-$height, $r);
$svg .= fractal( $x3, $y1, $x3-$side/2, $y1-$height, $x3+$side/2, $y1-$height, $r);
}
open my $fh, '>', 'run/sierpinski_triangle.svg';
print $fh <<'EOD',
<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="100%" height="100%" version="1.1" xmlns="http://www.w3.org/2000/svg">
<defs>
<radialGradient id="basegradient" cx="50%" cy="65%" r="50%" fx="50%" fy="65%">
<stop offset="10%" stop-color="#ff0" />
<stop offset="60%" stop-color="#f00" />
<stop offset="99%" stop-color="#00f" />
</radialGradient>
</defs>
EOD
triangle( $side/2, 0, 0, $height, $side, $height, 'url(#basegradient)' ),
triangle( $side/2, 0, 0, $height, $side, $height, '#000', 'animate' ),
'<g style="fill: #fff; stroke-width: 0;">',
fractal( $side/2, $height, $side*3/4, $height/2, $side/4, $height/2, $levels ),
'</g></svg>'; |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #C | C | "Soon Rising","Dee","Lesace","10-12-2000","New Hat Press"
"Brave Chicken","Tang","Owe","04-01-2008","Nowhere Press"
"Aardvark Point","Dee","Lesace","5-24-2001","New Hat Press"
"Bat Whisperer, The","Tang","Owe","01-03-2004","Nowhere Press"
"Treasure Beach","Argus","Jemky","09-22-1999","Lancast"
|
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #C | C | #include <stdio.h>
#include <string.h>
typedef struct link link_t;
struct link {
int len;
char letter;
link_t *next;
};
// Stores a copy of a SCS of x and y in out. Caller needs to make sure out is long enough.
int scs(char *x, char *y, char *out)
{
int lx = strlen(x), ly = strlen(y);
link_t lnk[ly + 1][lx + 1];
for (int i = 0; i < ly; i++)
lnk[i][lx] = (link_t) {ly - i, y[i], &lnk[i + 1][lx]};
for (int j = 0; j < lx; j++)
lnk[ly][j] = (link_t) {lx - j, x[j], &lnk[ly][j + 1]};
lnk[ly][lx] = (link_t) {0};
for (int i = ly; i--; ) {
for (int j = lx; j--; ) {
link_t *lp = &lnk[i][j];
if (y[i] == x[j]) {
lp->next = &lnk[i+1][j+1];
lp->letter = x[j];
} else if (lnk[i][j+1].len < lnk[i+1][j].len) {
lp->next = &lnk[i][j+1];
lp->letter = x[j];
} else {
lp->next = &lnk[i+1][j];
lp->letter = y[i];
}
lp->len = lp->next->len + 1;
}
}
for (link_t *lp = &lnk[0][0]; lp; lp = lp->next)
*out++ = lp->letter;
return 0;
}
int main(void)
{
char x[] = "abcbdab", y[] = "bdcaba", res[128];
scs(x, y, res);
printf("SCS(%s, %s) -> %s\n", x, y, res);
return 0;
} |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #XPL0 | XPL0 | include c:\cxpl\stdlib; \standard library provides mouse routines, etc.
def Ww=40, Wh=12, Wx=(80-Ww)/2, Wy=(25-Wh)/2; \window width, etc.
def Bw=11, Bh=4, Bx=Wx+(Ww-Bw)/2, By=Wy+3*(Wh-Bh)/4; \button size & position
int Clicks, Mx, My; \number of clicks and mouse coordinates
[ShowCursor(false); \turn off flashing cursor
Attrib($1F); \bright white characters on blue
SetWind(Wx, Wy, Wx+Ww, Wy+Wh, 2, true); \blue window with no scroll
DrawBox(Wx, Wy, Wx+Ww, Wy+Wh, 3); \draw borders
Cursor(Wx+5, Wy+3); Text(6, "There have been no clicks yet.");
DrawBox(Bx, By, Bx+Bw, By+Bh, 0); \draw button
Cursor(Bx+2, By+2); Text(6, "Click me");
OpenMouse;
ShowMouse(true);
Clicks:= 0;
repeat if GetMouseButton(0) then \left button down
[while GetMouseButton(0) do []; \wait for release
Mx:= GetMousePosition(0) / 8; \character coordinates
My:= GetMousePosition(1) / 8;
if Mx>=Bx & Mx<=Bx+Bw & My>=By & My<=By+Bh then
[Clicks:= Clicks+1; \mouse pointer is on the button
Cursor(Wx+4, Wy+3);
Text(6, "Times button has been clicked: ");
IntOut(6, Clicks);
];
];
until ChkKey; \keystroke terminates program
SetVid(3); \turn off mouse and turn on flashing cursor
] |
http://rosettacode.org/wiki/Simple_windowed_application | Simple windowed application | Task
Create a window that has:
a label that says "There have been no clicks yet"
a button that says "click me"
Upon clicking the button with the mouse, the label should change and show the number of times the button has been clicked.
| #Yorick | Yorick | #include "button.i"
window, 0;
btn_click = Button(text="click me", x=.395, y=.65, dx=0.04368, dy=0.0091);
btn_quit = Button(text="quit", x=.395, y=.6, dx=0.02184, dy=0.0091);
count = 0;
msg = "There have been no clicks yet";
finished = 0;
do {
fma;
plt, msg, .395, .7, justify="CH";
button_plot, btn_click;
button_plot, btn_quit;
xy = mouse(0, 0, "");
if(button_test(btn_click, xy(1), xy(2))) {
count++;
msg = swrite(format="Number of clicks: %d", count);
} else if(button_test(btn_quit, xy(1), xy(2))) {
finished = 1;
winkill, 0;
}
} while(!finished); |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Fortran | Fortran | ' FB 1.05.0 Win64
#Include "vbcompat.bi"
' The first argument to the Format function is a date serial
' and so the first statement below displays the epoch.
Dim f As String = "mmmm d, yyyy hh:mm:ss"
Print Format( 0 , f) '' epoch
Print Format( 0.5, f) '' noon on the same day
Print Format(-0.5, f) '' noon on the previous day
Print Format(1000000, f) '' one million days after the epoch
Print Format(-80000, f) '' eighty thousand days before the epoch
Print
Print "Press any key to quit"
Sleep |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
#Include "vbcompat.bi"
' The first argument to the Format function is a date serial
' and so the first statement below displays the epoch.
Dim f As String = "mmmm d, yyyy hh:mm:ss"
Print Format( 0 , f) '' epoch
Print Format( 0.5, f) '' noon on the same day
Print Format(-0.5, f) '' noon on the previous day
Print Format(1000000, f) '' one million days after the epoch
Print Format(-80000, f) '' eighty thousand days before the epoch
Print
Print "Press any key to quit"
Sleep |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Quackery | Quackery | [ $ "turtleduck.qky" loadfile ] now!
[ [ 1 1
30 times
[ tuck + ]
swap join ] constant
do ] is phi ( --> n/d )
[ 5 times
[ 2dup walk
1 5 turn ]
2drop ] is pentagon ( n/d n --> )
forward is pentaflake
[ dup 0 = iff
[ drop
' [ 79 126 229 ] fill
pentagon ] done
1 - temp put
5 times
[ 2dup 2 1 phi v- v*
temp share pentaflake
2dup fly
1 5 turn ]
temp release
2drop ] resolves pentaflake ( n/d n --> )
turtle
3 10 turn
300 1 fly
2 5 turn
' [ 79 126 229 ] colour
400 1 5 pentaflake |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Racket | Racket | #lang racket/base
(require racket/draw pict racket/math racket/class)
;; exterior angle
(define 72-degrees (degrees->radians 72))
;; After scaling we'll have 2 sides plus a gap occupying the length
;; of a side before scaling. The gap is the base of an isosceles triangle
;; with a base angle of 72 degrees.
(define scale-factor (/ (+ 2 (* (cos 72-degrees) 2))))
;; Starting at the top of the highest pentagon, calculate
;; the top vertices of the other pentagons by taking the
;; length of the scaled side plus the length of the gap.
(define dist-factor (+ 1 (* (cos 72-degrees) 2)))
;; don't use scale, since it scales brushes too (making lines all tiny)
(define (draw-pentagon x y side depth dc)
(let recur ((x x) (y y) (side side) (depth depth))
(cond
[(zero? depth)
(define p (new dc-path%))
(send p move-to x y)
(for/fold ((x x) (y y) (α (* 3 72-degrees))) ((i 5))
(send p line-to x y)
(values (+ x (* side (cos α)))
(- y (* side (sin α)))
(+ α 72-degrees)))
(send p close)
(send dc draw-path p)]
[else
(define side/ (* side scale-factor))
(define dist (* side/ dist-factor))
;; The top positions form a virtual pentagon of their own,
;; so simply move from one to the other by changing direction.
(for/fold ((x x) (y y) (α (* 3 72-degrees))) ((i 5))
(recur x y side/ (sub1 depth))
(values (+ x (* dist (cos α)))
(- y (* dist (sin α)))
(+ α 72-degrees)))])))
(define (dc-draw-pentagon depth w h #:margin (margin 4))
(dc (lambda (dc dx dy)
(define old-brush (send dc get-brush))
(send dc set-brush (make-brush #:style 'transparent))
(draw-pentagon (/ w 2)
(* 3 margin)
(* (- (/ w 2) (* 2 margin))
(sin (/ pi 5)) 2)
depth
dc)
(send dc set-brush old-brush))
w h))
(dc-draw-pentagon 1 120 120)
(dc-draw-pentagon 2 120 120)
(dc-draw-pentagon 3 120 120)
(dc-draw-pentagon 4 120 120)
(dc-draw-pentagon 5 640 640) |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #Comal | Comal | 0010 DIM part$(FALSE:TRUE) OF 2
0020 part$(FALSE):=" ";part$(TRUE):="* "
0030 INPUT "Order? ":order#
0040 size#:=2^order#
0050 FOR y#:=size#-1 TO 0 STEP -1 DO
0060 PRINT " "*y#,
0070 FOR x#:=0 TO size#-y#-1 DO PRINT part$(x# BITAND y#=0),
0080 PRINT
0090 ENDFOR y#
0100 END |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Phix | Phix | -- demo\rosetta\SierpinskyTriangle.exw
include pGUI.e
Ihandle dlg, canvas
cdCanvas cddbuffer, cdcanvas
procedure SierpinskyTriangle(integer level, atom x, atom y, atom w, atom h)
atom w2 = w/2, w4 = w/4, h2 = h/2
if level=1 then
cdCanvasBegin(cddbuffer,CD_CLOSED_LINES)
cdCanvasVertex(cddbuffer, x, y)
cdCanvasVertex(cddbuffer, x+w2, y+h)
cdCanvasVertex(cddbuffer, x+w, y)
cdCanvasEnd(cddbuffer)
else
SierpinskyTriangle(level-1, x, y, w2, h2)
SierpinskyTriangle(level-1, x+w4, y+h2, w2, h2)
SierpinskyTriangle(level-1, x+w2, y, w2, h2)
end if
end procedure
integer level = 7
function redraw_cb(Ihandle /*ih*/, integer /*posx*/, integer /*posy*/)
integer {w, h} = IupGetIntInt(canvas, "DRAWSIZE")
cdCanvasActivate(cddbuffer)
cdCanvasClear(cddbuffer)
SierpinskyTriangle(level, w*0.05, h*0.05, w*0.9, h*0.9)
cdCanvasFlush(cddbuffer)
IupSetStrAttribute(dlg, "TITLE", "Sierpinsky Triangle (level %d)",{level})
return IUP_DEFAULT
end function
function map_cb(Ihandle ih)
cdcanvas = cdCreateCanvas(CD_IUP, ih)
cddbuffer = cdCreateCanvas(CD_DBUFFER, cdcanvas)
cdCanvasSetBackground(cddbuffer, CD_WHITE)
cdCanvasSetForeground(cddbuffer, CD_GRAY)
return IUP_DEFAULT
end function
function esc_close(Ihandle /*ih*/, atom c)
if c=K_ESC then return IUP_CLOSE end if
if find(c,"+-") then
level = max(1,min(12,level+','-c))
IupRedraw(canvas)
end if
return IUP_CONTINUE
end function
procedure main()
IupOpen()
canvas = IupCanvas(NULL)
IupSetAttribute(canvas, "RASTERSIZE", "640x640")
IupSetCallback(canvas, "MAP_CB", Icallback("map_cb"))
IupSetCallback(canvas, "ACTION", Icallback("redraw_cb"))
dlg = IupDialog(canvas)
IupSetAttribute(dlg, "TITLE", "Sierpinsky Triangle")
IupSetCallback(dlg, "K_ANY", Icallback("esc_close"))
IupShow(dlg)
IupSetAttribute(canvas, "RASTERSIZE", NULL)
if platform()!=JS then
IupMainLoop()
IupClose()
end if
end procedure
main()
|
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #C.23 | C# |
using System;
using System.IO;
namespace Simple_database
{
class Program
{
public static void Main(string[] args)
{
//
// For appropriate use of this program
// use standard Windows Command Processor or cmd.exe
//
// Create cmd.bat file at the same folder with executive version
// of program Simple_database.exe, so when started, the correct
// file path will be automatically set to cmd console.
//
// Start notepad, write only cmd.exe and save file as cmd.bat
//
// To start cmd just double click at cmd.bat file.
//
//
//
// Console application command line start command
//
// application name.exe [argument] [argument parameters]
//
//
// Command line argument followed by parameters
//
// [a] - Add new entry
//
// ["data1"]["data2"]["data3"]...["data n"]
//
// ["data1"] - Data category !
// ["data2"] - Data
// ["data3"] - Data
//
//
// NOTICE !
//
// First parameter is taken for data category.
//
//
//
// Command line argument with no parameters
//
// [p1] - Print the latest entry
//
// [p2] - Print the latest entry for each category
//
// [p3] - Print all entries sorted by a date
//
//
//
//
// Command line example
//
// Small_database.exe [a] ["home"] ["+398125465458"] ["My tel number"]
//
// Small_database.exe [a] ["office"] ["+398222789000"] ["Boss"]
//
// Small_database.exe [a] [cd] ["Action movie"] ["Movie title"]
// Small_database.exe [a] [cd] ["SF movie"] ["Movie title"]
// Small_database.exe [a] [dvd] ["Action movie"] ["Movie title"]
//
//
// NOTICE !
//
// Brackets and space between arguments and parameters are necessary.
// Quotes must be used when parameters have more than one word.
//
// If not used as shown in examples, program will show error message.
//
//
//
// Check command line for arguments
//
//
if(args.Length==0)
{
Console.WriteLine();
Console.WriteLine(" Missing Argument Error. ");
Console.WriteLine();
}
else
{
switch (args[0])
{
case "[a]" : Add_New_Entry(args);
break;
case "[p1]": Print_Document("Print the latest entry.txt");
break;
case "[p2]": Print_Document("Print the latest entry for each category.txt");
break;
case "[p3]": Print_Document("Print all entries sorted by a date.txt");
break;
default :
{
Console.WriteLine();
Console.WriteLine(" Incorrect Argument Error. ");
Console.WriteLine();
}
break;
}
}
}
static void Add_New_Entry(string [] args)
{
//
// Check parameters
//
//
// Minimum one parameter, category
//
if(args.Length==1)
{
Console.WriteLine();
Console.WriteLine(" Missing Parameters Error..... ");
Console.WriteLine();
}
else
{
bool parameters_ok = true;
foreach (string a in args)
{
if(!a.StartsWith("[") || !a.EndsWith("]"))
{
parameters_ok = !parameters_ok;
break;
}
}
//
// Add new entry to Data base document
//
if(parameters_ok)
{
//
//
//
Console.WriteLine();
Console.WriteLine(" Parameters are ok..... ");
Console.WriteLine();
Console.WriteLine(" Writing new entry to database..... ");
//
// Create new Data base entry
//
args[0] = string.Empty;
string line = string.Empty;
foreach (string a in args)
{
line+=a;
}
line+="[" + DateTime.Now.ToString() + "]";
args[0] = "[" + DateTime.Now.ToString() + "]";
//
// Write entry to Data base
//
StreamWriter w = new StreamWriter("Data base.txt",true);
w.WriteLine(line);
//
// Close and dispose stream writer
//
w.Close();
w.Dispose();
//
//
//
Console.WriteLine();
Console.WriteLine(" New entry is written to database. ");
Create_Print_Documents(args);
//
//
//
Console.WriteLine();
Console.WriteLine(" Add new entry command executed. ");
//
//
//
}
else
{
Console.WriteLine();
Console.WriteLine(" ! Parameters are not ok ! ");
Console.WriteLine();
Console.WriteLine(" Add new entry command is not executed. ");
Console.WriteLine();
}
}
}
static void Create_Print_Documents(string [] args)
{
//
//
//
Console.WriteLine();
Console.WriteLine(" Creating new print documents. ");
//
// Create "Print all entries sorted by a date.txt"
//
File.Copy("Data base.txt","Print all entries sorted by a date.txt",true);
//
//
//
Console.WriteLine();
Console.WriteLine(" Print all entries sorted by a date.txt created. ");
//
// Create "Print the latest entry.txt"
//
//
// Create new entry
//
string line = string.Empty;
foreach (string a in args)
{
line+=a;
}
//
StreamWriter w = new StreamWriter("Print the latest entry.txt");
//
w.WriteLine(line);
//
w.Close();
w.Dispose();
//
//
//
Console.WriteLine();
Console.WriteLine(" Print the latest entry.txt created. ");
//
// Create "Print the latest entry for each category.txt"
//
string latest_entry = string.Empty;
foreach (string a in args)
{
latest_entry+=a;
}
if(!File.Exists("Print the latest entry for each category.txt"))
{
File.WriteAllText("Print the latest entry for each category.txt",latest_entry);
}
else
{
StreamReader r = new StreamReader("Print the latest entry for each category.txt");
//
w = new StreamWriter("Print the latest entry for each category 1.txt",true);
//
line = string.Empty;
//
while(!r.EndOfStream)
{
line = r.ReadLine();
if(line.Contains(args[1].ToString()))
{
w.WriteLine(latest_entry);
latest_entry = "ok";
}
else
{
w.WriteLine(line);
}
}
// add new category
if(latest_entry != "ok")
w.WriteLine(latest_entry);
//
w.Close();
w.Dispose();
//
r.Close();
r.Dispose();
//
File.Copy("Print the latest entry for each category 1.txt",
"Print the latest entry for each category.txt",true);
//
File.Delete("Print the latest entry for each category 1.txt");
//
//
//
Console.WriteLine();
Console.WriteLine(" Print the latest entry for each category.txt created. ");
Console.WriteLine();
}
}
static void Print_Document(string file_name)
{
//
// Print document
//
Console.WriteLine();
Console.WriteLine(file_name.Replace(".txt","")+ " : ");
Console.WriteLine();
//
StreamReader r = new StreamReader(file_name);
//
string line = string.Empty;
//
line = r.ReadToEnd();
//
Console.WriteLine(line);
//
r.Close();
r.Dispose();
//
//
//
}
}
}
|
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #C.23 | C# | public class ShortestCommonSupersequence
{
Dictionary<(string, string), string> cache = new();
public string scs(string x, string y)
{
if (x.Length == 0) return y;
if (y.Length == 0) return x;
if (cache.TryGetValue((x, y), out var result)) return result;
if (x[0] == y[0])
{
return cache[(x, y)] = x[0] + scs(x.Substring(1), y.Substring(1));
}
var xr = scs(x.Substring(1), y);
var yr = scs(x, y.Substring(1));
if (yr.Length <= xr.Length)
{
return cache[(x, y)] = y[0] + yr;
}
else
{
return cache[(x, y)] = x[0] + xr;
}
}
public static void Main(string[] args)
{
var scs = new ShortestCommonSupersequence();
Console.WriteLine(scs.scs("abcbdab", "bdcaba"));
}
}
|
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #FutureBasic | FutureBasic | window 1
print date$
print date$("d MMM yyyy")
print date$("EEE, MMM d, yyyy")
print date$("MMMM d, yyyy ")
print date$("MMMM d, yyyy G")
print "This is day ";date$("D");" of the year"
print
print time$
print time$("hh:mm:ss")
print time$("h:mm a")
print time$("h:mm a zzz")
print
print time$("h:mm a ZZZZ "); date$("MMMM d, yyyy G")
HandleEvents |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Go | Go | package main
import ("fmt"; "time")
func main() {
fmt.Println(time.Time{})
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Groovy | Groovy | def date = new Date(0)
def format = new java.text.SimpleDateFormat('yyyy-MM-dd\'T\'HH:mm:ss.SSSZ')
format.timeZone = TimeZone.getTimeZone('UTC')
println (format.format(date)) |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Raku | Raku | constant $sides = 5;
constant order = 5;
constant $dim = 250;
constant scaling-factor = ( 3 - 5**.5 ) / 2;
my @orders = ((1 - scaling-factor) * $dim) «*» scaling-factor «**» (^order);
my $fh = open('sierpinski_pentagon.svg', :w);
$fh.say: qq|<svg height="{$dim*2}" width="{$dim*2}" style="fill:blue" version="1.1" xmlns="http://www.w3.org/2000/svg">|;
my @vertices = map { cis( $_ * τ / $sides ) }, ^$sides;
for 0 ..^ $sides ** order -> $i {
my $vector = [+] @vertices[$i.base($sides).fmt("%{order}d").comb] «*» @orders;
$fh.say: pgon ((@orders[*-1] * (1 - scaling-factor)) «*» @vertices «+» $vector)».reals».fmt("%0.3f");
};
sub pgon (@q) { qq|<polygon points="{@q}" transform="translate({$dim},{$dim}) rotate(-18)"/>| }
$fh.say: '</svg>';
$fh.close; |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #Common_Lisp | Common Lisp | (defun print-sierpinski (order)
(loop with size = (expt 2 order)
repeat size
for v = (expt 2 (1- size)) then (logxor (ash v -1) (ash v 1))
do (fresh-line)
(loop for i below (integer-length v)
do (princ (if (logbitp i v) "*" " "))))) |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #PicoLisp | PicoLisp | (de sierpinski (N)
(let (D '("1") S "0")
(do N
(setq
D (conc
(mapcar '((X) (pack S X S)) D)
(mapcar '((X) (pack X "0" X)) D) )
S (pack S S) ) )
D ) )
(out '(display -)
(let Img (sierpinski 7)
(prinl "P1")
(prinl (length (car Img)) " " (length Img))
(mapc prinl Img) ) )
|
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #PostScript | PostScript | %!PS
/sierp { % level ax ay bx by cx cy
6 cpy triangle
sierpr
} bind def
/sierpr {
12 cpy
10 -4 2 {
5 1 roll exch 4 -1 roll
add 0.5 mul 3 1 roll
add 0.5 mul 3 -1 roll
2 roll
} for % l a b c bc ac ab
13 -1 roll dup 0 gt {
1 sub
dup 4 cpy 18 -2 roll sierpr
dup 7 index 7 index 2 cpy 16 -2 roll sierpr
9 3 roll 1 index 1 index 2 cpy 13 4 roll sierpr
} { 13 -6 roll 7 { pop } repeat } ifelse
triangle
} bind def
/cpy { { 5 index } repeat } bind def
/triangle {
newpath moveto lineto lineto closepath stroke
} bind def
6 50 100 550 100 300 533 sierp
showpage |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
######### #########
# ## ## # # ## ## #
######### #########
### ### ### ###
# # # # # # # #
### ### ### ###
######### #########
# ## ## # # ## ## #
######### #########
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
The use of the # character is not rigidly required for ASCII art.
The important requirement is the placement of whitespace and non-whitespace characters.
Related task
Sierpinski triangle
| #11l | 11l | F sierpinski_carpet(n)
V carpet = [String(‘#’)]
L 1..n
carpet = carpet.map(x -> x‘’x‘’x)
[+] carpet.map(x -> x‘’x.replace(‘#’, ‘ ’)‘’x)
[+] carpet.map(x -> x‘’x‘’x)
R carpet.join("\n")
print(sierpinski_carpet(3)) |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #COBOL | COBOL | IDENTIFICATION DIVISION.
PROGRAM-ID. simple-database.
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT OPTIONAL database-file ASSIGN Database-Path
ORGANIZATION INDEXED
ACCESS SEQUENTIAL
RECORD KEY data-title
ALTERNATE RECORD KEY data-tag
WITH DUPLICATES
ALTERNATE RECORD KEY date-added
WITH DUPLICATES
FILE STATUS file-status
.
DATA DIVISION.
FILE SECTION.
FD database-file.
01 database-record.
*> Date is in YYYYMMDD format.
03 date-added PIC 9(8).
03 data-tag PIC X(20).
03 data-title PIC X(50).
03 data-contents PIC X(200).
*> Adding extra space is considered good style so the record
*> can be expanded in the future.
03 FILLER PIC X(50).
WORKING-STORAGE SECTION.
78 Database-Path VALUE "database.dat".
01 file-status PIC XX.
88 file-ok VALUE "00".
88 duplicate-key VALUE "22".
88 key-not-found VALUE "23".
01 num-args PIC 99.
01 action PIC XX.
88 create-entry VALUE "-c".
88 remove-entry VALUE "-r".
88 find-entry VALUE "-f".
88 print-latest VALUE "-l".
88 print-database VALUES "-a", "-d", "-t".
*> Printed by title.
88 print-by-title VALUE "-a".
88 print-by-date VALUE "-d".
88 print-by-tag VALUE "-t".
88 print-help VALUES "-h", SPACES.
01 read-direction-flag PIC X VALUE SPACE.
88 read-backwards VALUE "B".
01 edited-date PIC 9(4)/99/99.
PROCEDURE DIVISION.
DECLARATIVES.
database-file-error SECTION.
USE AFTER ERROR ON database-file
DISPLAY "An error has occurred while using " Database-Path
". Error no. " file-status
DISPLAY "The program will terminate."
CLOSE database-file
GOBACK
.
END DECLARATIVES.
main-line.
DISPLAY 1 UPON ARGUMENT-NUMBER
ACCEPT action FROM ARGUMENT-VALUE
ACCEPT num-args FROM ARGUMENT-NUMBER
EVALUATE TRUE
WHEN create-entry
IF num-args >= 4
PERFORM write-entry
ELSE
DISPLAY "-a requires arguments to enter in the "
"database. See help (-h) for details."
END-IF
WHEN remove-entry
IF num-args >= 2
PERFORM delete-entry
ELSE
DISPLAY "-r requires the title of the entry to "
"delete."
END-IF
WHEN find-entry
IF num-args >= 2
PERFORM display-specified-entry
ELSE
DISPLAY "-f requires the title of the entry to "
"find."
END-IF
WHEN print-latest
PERFORM show-latest
WHEN print-database
PERFORM show-database
WHEN print-help
PERFORM show-general-help
WHEN OTHER
DISPLAY action " is not a valid option."
END-EVALUATE
GOBACK
.
write-entry.
OPEN EXTEND database-file
DISPLAY 2 UPON ARGUMENT-NUMBER
ACCEPT data-tag FROM ARGUMENT-VALUE
DISPLAY 3 UPON ARGUMENT-NUMBER
ACCEPT data-title FROM ARGUMENT-VALUE
IF data-title = SPACES
DISPLAY "The title cannot be blank."
PERFORM close-and-terminate
END-IF
DISPLAY 4 UPON ARGUMENT-NUMBER
ACCEPT data-contents FROM ARGUMENT-VALUE
ACCEPT date-added FROM DATE YYYYMMDD
WRITE database-record
INVALID KEY
IF duplicate-key
DISPLAY "An entry in the database already has "
"that title. Please choose a different "
"title or remove the entry."
ELSE
PERFORM database-file-error
END-IF
END-WRITE
PERFORM close-database
.
delete-entry.
PERFORM get-title-arg
OPEN I-O database-file
PERFORM read-title
DELETE database-file
PERFORM close-database
.
display-specified-entry.
PERFORM get-title-arg
OPEN INPUT database-file
PERFORM read-title
PERFORM show-record
PERFORM close-database
.
get-title-arg.
DISPLAY 2 UPON ARGUMENT-NUMBER
ACCEPT data-title FROM ARGUMENT-VALUE
.
read-title.
START database-file KEY IS = data-title
INVALID KEY
IF key-not-found
DISPLAY "An entry with that title was not found."
PERFORM close-and-terminate
ELSE
PERFORM database-file-error
END-IF
END-START
READ database-file
.
close-and-terminate.
PERFORM close-database
GOBACK
.
show-latest.
OPEN INPUT database-file
PERFORM start-at-last-date
READ database-file
PERFORM show-record
PERFORM close-database
.
show-database.
OPEN INPUT database-file
EVALUATE TRUE
WHEN print-by-title
*> Primary key is the title.
CONTINUE
WHEN print-by-tag
MOVE LOW-VALUES TO data-tag
START database-file KEY IS > data-tag
WHEN print-by-date
PERFORM start-at-last-date
SET read-backwards TO TRUE
END-EVALUATE
PERFORM FOREVER
*> The problem with statements instead of functions...
IF NOT read-backwards
READ database-file NEXT
AT END
EXIT PERFORM
END-READ
ELSE
READ database-file PREVIOUS
AT END
EXIT PERFORM
END-READ
END-IF
PERFORM show-record
DISPLAY SPACE
END-PERFORM
PERFORM close-database
.
start-at-last-date.
MOVE HIGH-VALUES TO date-added
START database-file KEY IS < date-added
.
close-database.
CLOSE database-file
.
show-record.
MOVE date-added TO edited-date
DISPLAY "Date added: " edited-date " Tag: " data-tag
DISPLAY "Title: " data-title
DISPLAY "Contents:"
DISPLAY " " FUNCTION TRIM(data-contents)
.
show-general-help.
DISPLAY "Help: Possible options are:"
DISPLAY " -a - Show all the entries (sorted by title)."
DISPLAY " -c - Create a new entry in the database. -c needs"
" further arguments in this format:"
DISPLAY ' "tag" "title" "content"'
DISPLAY " Max argument sizes (in characters): tag - 20, "
"title - 50, content - 200"
DISPLAY " The title must be unique and not be blank."
DISPLAY " -d - Show all the entries sorted by date added."
DISPLAY " -f - Finds and displays entry with the title "
"provided. The title should be specified as shown for "
"-c."
DISPLAY " -h - Show this help menu."
DISPLAY " -l - Show the latest entry."
DISPLAY " -r - Remove the entry with the title provided. "
"The title should be specified as shown for -c."
DISPLAY " -t - Show all the entries sorted by tag."
. |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #C.2B.2B | C++ | #include <iostream>
std::string scs(std::string x, std::string y) {
if (x.empty()) {
return y;
}
if (y.empty()) {
return x;
}
if (x[0] == y[0]) {
return x[0] + scs(x.substr(1), y.substr(1));
}
if (scs(x, y.substr(1)).size() <= scs(x.substr(1), y).size()) {
return y[0] + scs(x, y.substr(1));
} else {
return x[0] + scs(x.substr(1), y);
}
}
int main() {
auto res = scs("abcbdab", "bdcaba");
std::cout << res << '\n';
return 0;
} |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #D | D | import std.stdio, std.functional, std.array, std.range;
dstring scs(in dstring x, in dstring y) nothrow @safe {
alias mScs = memoize!scs;
if (x.empty) return y;
if (y.empty) return x;
if (x.front == y.front)
return x.front ~ mScs(x.dropOne, y.dropOne);
if (mScs(x, y.dropOne).length <= mScs(x.dropOne, y).length)
return y.front ~ mScs(x, y.dropOne);
else
return x.front ~ mScs(x.dropOne, y);
}
void main() @safe {
scs("abcbdab", "bdcaba").writeln;
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Haskell | Haskell | import System.Time
main = putStrLn $ calendarTimeToString $ toUTCTime $ TOD 0 0 |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Icon_and_Unicon | Icon and Unicon | link printf,datetime
procedure main()
# Unicon
now := gettimeofday().sec
if now = &now then printf("&now and gettimeofday().sec are equal\n")
printf("Now (UTC) %s, (local) %s\n",gtime(now),ctime(now))
printf("Epoch %s\n",gtime(0))
# Icon and Unicon
now := DateToSec(&date) + ClockToSec(&clock)
printf("Now is also %s and %s\n",SecToDate(now),SecToDateLine(now))
end |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Ruby | Ruby |
THETA = Math::PI * 2 / 5
SCALE_FACTOR = (3 - Math.sqrt(5)) / 2
MARGIN = 20
attr_reader :pentagons, :renderer
def settings
size(400, 400)
end
def setup
sketch_title 'Pentaflake'
radius = width / 2 - 2 * MARGIN
center = Vec2D.new(radius - 2 * MARGIN, 3 * MARGIN)
pentaflake = Pentaflake.new(center, radius, 5)
@pentagons = pentaflake.pentagons
end
def draw
background(255)
stroke(0)
pentagons.each do |penta|
draw_pentagon(penta)
end
no_loop
end
def draw_pentagon(pent)
points = pent.vertices
begin_shape
points.each do |pnt|
pnt.to_vertex(renderer)
end
end_shape(CLOSE)
end
def renderer
@renderer ||= GfxRender.new(self.g)
end
class Pentaflake
attr_reader :pentagons
def initialize(center, radius, depth)
@pentagons = []
create_pentagons(center, radius, depth)
end
def create_pentagons(center, radius, depth)
if depth.zero?
pentagons << Pentagon.new(center, radius)
else
radius *= SCALE_FACTOR
distance = radius * Math.sin(THETA) * 2
(0..4).each do |idx|
x = center.x + Math.cos(idx * THETA) * distance
y = center.y + Math.sin(idx * THETA) * distance
center = Vec2D.new(x, y)
create_pentagons(center, radius, depth - 1)
end
end
end
end
class Pentagon
attr_reader :center, :radius
def initialize(center, radius)
@center = center
@radius = radius
end
def vertices
(0..4).map do |idx|
center + Vec2D.new(radius * Math.sin(THETA * idx), radius * Math.cos(THETA * idx))
end
end
end
|
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #Cowgol | Cowgol | include "cowgol.coh";
include "argv.coh";
var order: uint8 := 4; # default order
# Read order from command line if there is an argument
ArgvInit();
var argmt := ArgvNext();
if argmt != 0 as [uint8] then
var a: int32;
(a, argmt) := AToI(argmt);
if a<3 or 7<a then
print("Order must be between 3 and 7.");
print_nl();
ExitWithError();
end if;
order := a as uint8;
end if;
var one: uint8 := 1; # shift argument can't be constant...
var size: uint8 := one << order;
var y: uint8 := size;
while y > 0 loop
var x: uint8 := 0;
while x < y-1 loop
print_char(' ');
x := x + 1;
end loop;
x := 0;
while x + y <= size loop
if x & (y-1) != 0 then
print(" ");
else
print("* ");
end if;
x := x + 1;
end loop;
print_nl();
y := y - 1;
end loop; |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Processing | Processing |
PVector [] coord = {new PVector(0, 0), new PVector(150, 300), new PVector(300, 0)};
void setup()
{
size(400,400);
background(32);
sierpinski(new PVector(150,150), 8);
noLoop();
}
void sierpinski(PVector cPoint, int cDepth)
{
if (cDepth == 0) {
set(50+int(cPoint.x), (height-50)-int(cPoint.y), color(192));
return;
}
for (int v=0; v<3; v++) {
sierpinski(new PVector((cPoint.x+coord[v].x)/2, (cPoint.y+coord[v].y)/2), cDepth-1);
}
}
|
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Prolog | Prolog | sierpinski(N) :-
sformat(A, 'Sierpinski order ~w', [N]),
new(D, picture(A)),
draw_Sierpinski(D, N, point(350,50), 600),
send(D, size, size(690,690)),
send(D, open).
draw_Sierpinski(Window, 1, point(X, Y), Len) :-
X1 is X - round(Len/2),
X2 is X + round(Len/2),
Y1 is Y + Len * sqrt(3) / 2,
send(Window, display, new(Pa, path)),
(
send(Pa, append, point(X, Y)),
send(Pa, append, point(X1, Y1)),
send(Pa, append, point(X2, Y1)),
send(Pa, closed, @on),
send(Pa, fill_pattern, colour(@default, 0, 0, 0))
).
draw_Sierpinski(Window, N, point(X, Y), Len) :-
Len1 is round(Len/2),
X1 is X - round(Len/4),
X2 is X + round(Len/4),
Y1 is Y + Len * sqrt(3) / 4,
N1 is N - 1,
draw_Sierpinski(Window, N1, point(X, Y), Len1),
draw_Sierpinski(Window, N1, point(X1, Y1), Len1),
draw_Sierpinski(Window, N1, point(X2, Y1), Len1). |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
######### #########
# ## ## # # ## ## #
######### #########
### ### ### ###
# # # # # # # #
### ### ### ###
######### #########
# ## ## # # ## ## #
######### #########
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
The use of the # character is not rigidly required for ASCII art.
The important requirement is the placement of whitespace and non-whitespace characters.
Related task
Sierpinski triangle
| #Action.21 | Action! | BYTE FUNC InCarpet(BYTE x,y)
DO
IF x MOD 3=1 AND y MOD 3=1 THEN
RETURN (0)
FI
x==/3 y==/3
UNTIL x=0 AND y=0
OD
RETURN (1)
PROC DrawCarpet(INT x0 BYTE y0,depth)
BYTE i,x,y,size
size=1
FOR i=1 TO depth
DO size==*3 OD
FOR y=0 TO size-1
DO
FOR x=0 TO size-1
DO
IF InCarpet(x,y) THEN
Plot(x0+2*x,y0+2*y)
Plot(x0+2*x+1,y0+2*y)
Plot(x0+2*x+1,y0+2*y+1)
Plot(x0+2*x,y0+2*y+1)
FI
OD
OD
RETURN
PROC Main()
BYTE CH=$02FC,COLOR1=$02C5,COLOR2=$02C6
Graphics(8+16)
Color=1
COLOR1=$0C
COLOR2=$02
DrawCarpet(79,15,4)
DO UNTIL CH#$FF OD
CH=$FF
RETURN |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #Common_Lisp | Common Lisp | (defvar *db* nil)
(defvar *db-cat* (make-hash-table :test 'equal))
(defvar *db-file* "db.txt")
(defstruct item
"this is the unit of data stored/displayed in *db*"
(title " ")
(category "default")
(date (progn (get-universal-time))))
(defun set-category(new-item)
(setf (gethash (item-category new-item) *db-cat*) 't))
(defun find-item-in-db (&optional category)
(if (null category)
(car *db*)
(find category *db* :key #'item-category :test #'string=)))
(defun scan-category ()
"scan categories from an existing database -- after reading it from disk"
(dolist (itm *db*) (set-category itm)))
(defun pr-univ-time (utime)
(multiple-value-bind
(second minute hour date month year day-of-week dst-p tz)
(decode-universal-time utime)
(declare (ignore day-of-week dst-p tz))
(format nil "~4,'0d-~2,'0d-~2,'0d ~2,'0d:~2,'0d:~2,'0d" year month date hour minute second)))
(defun pr (&optional (item (find-item-in-db)) (stream t))
"print an item"
(when item
(format stream "~a: (~a) (~a)~%"
(item-title item)
(item-category item)
(pr-univ-time (item-date item)))))
(defun pr-per-category ()
"print the latest item from each category"
(loop for k being the hash-keys in *db-cat*
do (pr (find-item-in-db k))))
(defun pr-all ()
"print all the items, *db* is sorted by time."
(dolist (itm *db*) (pr itm)))
(defun pr-all-categories (&optional (stream t))
(loop for k being the hash-keys in *db-cat*
do (format stream "(~a) " k)))
(defun insert-item (item)
"insert item into database in a time sorted list. okay for a small list, as per spec."
(let ((first-item (car *db*)) (new-itm item))
(set-category new-itm)
(push new-itm *db*)
(when (and first-item (>= (item-date new-itm) (item-date first-item)))
(setf *db* (sort *db* #'> :key #'item-date)))
*db*))
(defun read-db-from-file (&optional (file *db-file*))
(with-open-file (in file :if-does-not-exist nil)
(when in
(with-standard-io-syntax (setf *db* (read in)))
(scan-category))))
(defun save-db-to-file (&optional (file *db-file*))
(with-open-file (out file :direction :output :if-exists :supersede)
(with-standard-io-syntax
(print *db* out))))
(defun del-db ()
(setf *db* nil)
(save-db-to-file))
(defun del-item (itm)
(read-db-from-file)
(setf *db* (remove itm *db* :key #'item-title :test #'string=))
(save-db-to-file))
(defun add-item-to-db (args)
(read-db-from-file)
(insert-item (make-item :title (first args) :category (second args)))
(save-db-to-file))
(defun help-menu ()
(format t "clisp db.lisp ~{~15T~a~^~% ~}"
'("delete <item-name> ------------------- delete an item"
"delete-all --------------------------- delete the database"
"insert <item-name> <item-category> --- insert an item with its category"
"show --------------------------------- shows the latest inserted item"
"show-categories ---------------------- show all categories"
"show-all ----------------------------- show all items"
"show-per-category -------------------- show the latest item per category")))
(defun db-cmd-run (args)
(cond ((and (> (length args) 1) (equal (first args) "delete"))
(del-item (second args)))
((equal (first args) "delete-all") (del-db))
((and (> (length args) 2) (equal (first args) "insert"))
(add-item-to-db (rest args)))
((equal (first args) "show") (read-db-from-file) (pr))
((equal (first args) "show-categories") (read-db-from-file) (pr-all-categories))
((equal (first args) "show-all") (read-db-from-file) (pr-all))
((equal (first args) "show-per-category") (read-db-from-file) (pr-per-category))
(t (help-menu))))
;; modified https://rosettacode.org/wiki/Command-line_arguments#Common_Lisp
(defun db-argv ()
(or
#+clisp ext:*args*
#+sbcl (cdr sb-ext:*posix-argv*)
#+allegro (cdr (sys:command-line-arguments))
#+lispworks (cdr sys:*line-arguments-list*)
nil))
(db-cmd-run (db-argv)) |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #Elixir | Elixir | defmodule SCS do
def scs(u, v) do
lcs = LCS.lcs(u, v) |> to_charlist
scs(to_charlist(u), to_charlist(v), lcs, []) |> to_string
end
defp scs(u, v, [], res), do: Enum.reverse(res) ++ u ++ v
defp scs([h|ut], [h|vt], [h|lt], res), do: scs(ut, vt, lt, [h|res])
defp scs([h|_]=u, [vh|vt], [h|_]=lcs, res), do: scs(u, vt, lcs, [vh|res])
defp scs([uh|ut], v, lcs, res), do: scs(ut, v, lcs, [uh|res])
end
u = "abcbdab"
v = "bdcaba"
IO.puts "SCS(#{u}, #{v}) = #{SCS.scs(u, v)}" |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #Factor | Factor | USING: combinators io kernel locals math memoize sequences ;
MEMO:: scs ( x y -- seq )
{
{ [ x empty? ] [ y ] }
{ [ y empty? ] [ x ] }
{ [ x first y first = ]
[ x rest y rest scs x first prefix ] }
{ [ x y rest scs length x rest y scs length <= ]
[ x y rest scs y first prefix ] }
[ x rest y scs x first prefix ]
} cond ;
"abcbdab" "bdcaba" scs print |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #Go | Go | package main
import (
"fmt"
"strings"
)
func lcs(x, y string) string {
xl, yl := len(x), len(y)
if xl == 0 || yl == 0 {
return ""
}
x1, y1 := x[:xl-1], y[:yl-1]
if x[xl-1] == y[yl-1] {
return fmt.Sprintf("%s%c", lcs(x1, y1), x[xl-1])
}
x2, y2 := lcs(x, y1), lcs(x1, y)
if len(x2) > len(y2) {
return x2
} else {
return y2
}
}
func scs(u, v string) string {
ul, vl := len(u), len(v)
lcs := lcs(u, v)
ui, vi := 0, 0
var sb strings.Builder
for i := 0; i < len(lcs); i++ {
for ui < ul && u[ui] != lcs[i] {
sb.WriteByte(u[ui])
ui++
}
for vi < vl && v[vi] != lcs[i] {
sb.WriteByte(v[vi])
vi++
}
sb.WriteByte(lcs[i])
ui++
vi++
}
if ui < ul {
sb.WriteString(u[ui:])
}
if vi < vl {
sb.WriteString(v[vi:])
}
return sb.String()
}
func main() {
u := "abcbdab"
v := "bdcaba"
fmt.Println(scs(u, v))
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #J | J | 6!:0''
2011 8 8 20 25 44.725 |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Java | Java | import java.text.DateFormat;
import java.util.Date;
import java.util.TimeZone;
public class DateTest{
public static void main(String[] args) {
Date date = new Date(0);
DateFormat format = DateFormat.getDateTimeInstance();
format.setTimeZone(TimeZone.getTimeZone("UTC"));
System.out.println(format.format(date));
}
} |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Rust | Rust | // [dependencies]
// svg = "0.8.0"
fn sierpinski_pentagon(
mut document: svg::Document,
mut x: f64,
mut y: f64,
mut side: f64,
order: usize,
) -> svg::Document {
use std::f64::consts::PI;
use svg::node::element::Polygon;
let degrees72 = 0.4 * PI;
let mut angle = 3.0 * degrees72;
let scale_factor = 1.0 / (2.0 + degrees72.cos() * 2.0);
if order == 1 {
let mut points = Vec::new();
points.push((x, y));
for _ in 0..5 {
x += angle.cos() * side;
y -= angle.sin() * side;
angle += degrees72;
points.push((x, y));
}
let polygon = Polygon::new()
.set("fill", "blue")
.set("stroke", "black")
.set("stroke-width", "1")
.set("points", points);
document = document.add(polygon);
} else {
side *= scale_factor;
let distance = side + side * degrees72.cos() * 2.0;
for _ in 0..5 {
x += angle.cos() * distance;
y -= angle.sin() * distance;
angle += degrees72;
document = sierpinski_pentagon(document, x, y, side, order - 1);
}
}
document
}
fn write_sierpinski_pentagon(file: &str, size: usize, order: usize) -> std::io::Result<()> {
use std::f64::consts::PI;
use svg::node::element::Rectangle;
let margin = 5.0;
let radius = (size as f64) / 2.0 - 2.0 * margin;
let side = radius * (0.2 * PI).sin() * 2.0;
let height = side * ((0.2 * PI).sin() + (0.4 * PI).sin());
let x = (size as f64) / 2.0;
let y = (size as f64 - height) / 2.0;
let rect = Rectangle::new()
.set("width", "100%")
.set("height", "100%")
.set("fill", "white");
let mut document = svg::Document::new()
.set("width", size)
.set("height", size)
.add(rect);
document = sierpinski_pentagon(document, x, y, side, order);
svg::save(file, &document)
}
fn main() {
write_sierpinski_pentagon("sierpinski_pentagon.svg", 600, 5).unwrap();
} |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Scala | Scala | import java.awt._
import java.awt.event.ActionEvent
import java.awt.geom.Path2D
import javax.swing._
import scala.annotation.tailrec
import scala.math.{Pi, cos, sin, sqrt}
object SierpinskiPentagon extends App {
SwingUtilities.invokeLater(() => {
class SierpinskiPentagon extends JPanel {
/* Try to avoid random color values clumping together */
private var hue = math.random
// exterior angle
private val deg072 = 2 * Pi / 5d //toRadians(72)
/* After scaling we'll have 2 sides plus a gap occupying the length
of a side before scaling. The gap is the base of an isosceles triangle
with a base angle of 72 degrees. */
//private val scaleFactor = 1 / (2 + cos(deg072) * 2)
private var limit = 0
private def drawPentagon(g: Graphics2D, x: Double, y: Double, side: Double, depth: Int): Unit = {
val scaleFactor = 1 / (2 + cos(deg072) * 2)
if (depth == 0) {
// draw from the top
@tailrec
def iter0(i: Int, x: Double, y: Double, angle: Double, p: Path2D.Double): Path2D.Double = {
if (i < 0) p
else {
p.lineTo(x, y)
iter0(i - 1, x + cos(angle) * side, y - sin(angle) * side, angle + deg072, p)
}
}
def p1: Path2D.Double = iter0(4, x, y, 3 * deg072, {
val p = new Path2D.Double
p.moveTo(x, y)
p
})
def p: Path2D.Double = iter0(4, x, y, 3 * deg072, p1)
def next: Color = {
hue = (hue + (sqrt(5) - 1) / 2) % 1
Color.getHSBColor(hue.toFloat, 1, 1)
}
g.setColor(next)
g.fill(p)
}
else {
val _side = side * scaleFactor
/* Starting at the top of the highest pentagon, calculate
the top vertices of the other pentagons by taking the
length of the scaled side plus the length of the gap. */
val distance = _side + _side * cos(deg072) * 2
/* The top positions form a virtual pentagon of their own,
so simply move from one to the other by changing direction. */
def iter1(i: Int, x: Double, y: Double, angle: Double): Unit = {
if (i < 0) ()
else {
drawPentagon(g, x, y, _side, depth - 1)
iter1(i - 1, x + cos(angle) * distance, y - sin(angle) * distance, angle + deg072)
}
}
iter1(4, x + cos(3 * deg072) * distance, y - sin(3 * deg072) * distance, 4 * deg072)
}
}
override def paintComponent(gg: Graphics): Unit = {
val (g, margin) = (gg.asInstanceOf[Graphics2D], 20)
val side = (getWidth / 2 - 2 * margin) * sin(Pi / 5) * 2
super.paintComponent(gg)
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON)
drawPentagon(g, getWidth / 2, 3 * margin, side, limit)
}
new Timer(3000, (_: ActionEvent) => {
limit += 1
if (limit >= 5) limit = 0
repaint()
}).start()
setPreferredSize(new Dimension(640, 640))
setBackground(Color.white)
}
val f = new JFrame("Sierpinski Pentagon") {
setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE)
setResizable(true)
add(new SierpinskiPentagon, BorderLayout.CENTER)
pack()
setLocationRelativeTo(null)
setVisible(true)
}
})
} |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #D | D | void main() /*@safe*/ {
import std.stdio, std.algorithm, std.string, std.array;
enum level = 4;
auto d = ["*"];
foreach (immutable n; 0 .. level) {
immutable sp = " ".replicate(2 ^^ n);
d = d.map!(a => sp ~ a ~ sp).array ~
d.map!(a => a ~ " " ~ a).array;
}
d.join('\n').writeln;
} |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Python | Python |
# a very simple version
import turtle as t
def sier(n,length):
if n == 0:
return
for i in range(3):
sier(n - 1, length / 2)
t.fd(length)
t.rt(120)
|
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
######### #########
# ## ## # # ## ## #
######### #########
### ### ### ###
# # # # # # # #
### ### ### ###
######### #########
# ## ## # # ## ## #
######### #########
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
The use of the # character is not rigidly required for ASCII art.
The important requirement is the placement of whitespace and non-whitespace characters.
Related task
Sierpinski triangle
| #Ada | Ada | with Ada.Text_Io; use Ada.Text_Io;
procedure Sierpinski_Carpet is
subtype Index_Type is Integer range 1..81;
type Pattern_Array is array(Index_Type range <>, Index_Type range <>) of Boolean;
Pattern : Pattern_Array(1..81,1..81) := (Others =>(others => true));
procedure Clear_Center(P : in out Pattern_Array; X1 : Index_Type; X2 : Index_Type;
Y1 : Index_Type; Y2 : Index_Type) is
Xfirst : Index_Type;
Xlast : Index_Type;
Yfirst : Index_Type;
Ylast : Index_Type;
Diff : Integer;
begin
Xfirst :=(X2 - X1 + 1) / 3 + X1;
Diff := Xfirst - X1;
Xlast := Xfirst + Diff;
Yfirst := (Y2 - Y1) / 3 + Y1;
YLast := YFirst + Diff;
for I in XFirst..XLast loop
for J in YFirst..YLast loop
P(I, J) := False;
end loop;
end loop;
end Clear_Center;
procedure Print(P : Pattern_Array) is
begin
for I in P'range(1) loop
for J in P'range(2) loop
if P(I,J) then
Put('*');
else
Put(' ');
end if;
end loop;
New_Line;
end loop;
end Print;
procedure Divide_Square(P : in out Pattern_Array; Order : Positive) is
Factor : Natural := 0;
X1, X2 : Index_Type;
Y1, Y2 : Index_Type;
Division : Index_Type;
Num_Sections : Index_Type;
begin
while Factor < Order loop
Num_Sections := 3**Factor;
Factor := Factor + 1;
X1 := P'First;
Division := P'Last / Num_Sections;
X2 := Division;
Y1 := X1;
Y2 := X2;
loop
loop
Clear_Center(P, X1, X2, Y1, Y2);
exit when X2 = P'Last;
X1 := X2;
X2 := X2 + Division;
end loop;
exit when Y2 = P'Last;
Y1 := Y2;
Y2 := Y2 + Division;
X1 := P'First;
X2 := Division;
end loop;
end loop;
end Divide_Square;
begin
Divide_Square(Pattern, 3);
Print(Pattern);
end Sierpinski_Carpet; |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #D | D | import std.stdio, std.algorithm, std.string, std.conv, std.array,
std.file, std.csv, std.datetime;
private {
immutable filename = "simdb.csv";
struct Item {
string name, date, category;
}
void addItem(in string[] item) {
if (item.length < 3)
return printUsage();
auto db = load();
const date = (cast(DateTime)Clock.currTime).toISOExtString;
const cat = (item.length == 4) ? item[3] : "none";
db ~= Item(item[2], date, cat);
store(db);
}
void printLatest(in string[] a) {
auto db = load();
if (db.empty)
return writeln("No entries in database.");
db.sort!q{ a.date > b.date };
if (a.length == 3) {
foreach (item; db)
if (item.category == a[2])
writefln("%s, %s, %s", item.tupleof);
} else {
writefln("%s, %s, %s", db[0].tupleof);
}
}
void printAll() {
auto db = load();
if (db.empty)
return writeln("No entries in database.");
db.sort!q{ a.date < b.date };
foreach (item; db)
writefln("%s, %s, %s", item.tupleof);
}
Item[] load() {
Item[] db;
if (filename.exists && filename.isFile) {
try {
const text = filename.readText;
if (!text.empty)
db = csvReader!Item(text).array;
} catch (CSVException e) {
writeln(e.msg);
}
}
return db;
}
void store(in Item[] db) {
auto f = File(filename, "w+");
foreach (item; db)
f.writefln("%s,%s,%s", item.tupleof);
}
void printUsage() {
writeln(
`Usage:
simdb cmd [categoryName]
add add item, followed by optional category
latest print last added item(s), followed by optional category
all print all
For instance: add "some item name" "some category name"`);
}
}
void main(in string[] args) {
if (args.length < 2 || args.length > 4)
return printUsage();
switch (args[1].toLower) {
case "add": addItem(args); break;
case "latest": printLatest(args); break;
case "all": printAll(); break;
default: printUsage(); break;
}
} |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #Haskell | Haskell | scs :: Eq a => [a] -> [a] -> [a]
scs [] ys = ys
scs xs [] = xs
scs xss@(x:xs) yss@(y:ys)
| x == y = x : scs xs ys
| otherwise = ws
where
us = scs xs yss
vs = scs xss ys
ws | length us < length vs = x : us
| otherwise = y : vs
main = putStrLn $ scs "abcbdab" "bdcaba" |
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #Java | Java | public class ShortestCommonSuperSequence {
private static boolean isEmpty(String s) {
return null == s || s.isEmpty();
}
private static String scs(String x, String y) {
if (isEmpty(x)) {
return y;
}
if (isEmpty(y)) {
return x;
}
if (x.charAt(0) == y.charAt(0)) {
return x.charAt(0) + scs(x.substring(1), y.substring(1));
}
if (scs(x, y.substring(1)).length() <= scs(x.substring(1), y).length()) {
return y.charAt(0) + scs(x, y.substring(1));
} else {
return x.charAt(0) + scs(x.substring(1), y);
}
}
public static void main(String[] args) {
System.out.println(scs("abcbdab", "bdcaba"));
}
} |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #JavaScript | JavaScript | document.write(new Date(0).toUTCString()); |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #jq | jq | 0 | todate |
http://rosettacode.org/wiki/Show_the_epoch | Show the epoch | Task
Choose popular date libraries used by your language and show the epoch those libraries use.
A demonstration is preferable (e.g. setting the internal representation of the date to 0 ms/ns/etc., or another way that will still show the epoch even if it is changed behind the scenes by the implementers), but text from (with links to) documentation is also acceptable where a demonstration is impossible/impractical.
For consistency's sake, show the date in UTC time where possible.
Related task
Date format
| #Julia | Julia | using Base.Dates # just using Dates in versions > 0.6
println("Time zero (the epoch) is $(unix2datetime(0)).") |
http://rosettacode.org/wiki/Sierpinski_pentagon | Sierpinski pentagon | Produce a graphical or ASCII-art representation of a Sierpinski pentagon (aka a Pentaflake) of order 5. Your code should also be able to correctly generate representations of lower orders: 1 to 4.
See also
Sierpinski pentagon
| #Sidef | Sidef | define order = 5
define sides = 5
define dim = 500
define scaling_factor = ((3 - 5**0.5) / 2)
var orders = order.of {|i| ((1-scaling_factor) * dim) * scaling_factor**i }
say <<"STOP";
<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
"http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg height="#{dim*2}" width="#{dim*2}"
style="fill:blue" transform="translate(#{dim},#{dim}) rotate(-18)"
version="1.1" xmlns="http://www.w3.org/2000/svg">
STOP
var vertices = sides.of {|i| Complex(0, i * Number.tau / sides).exp }
for i in ^(sides**order) {
var vector = ([vertices["%#{order}d" % i.base(sides) -> chars]] »*« orders «+»)
var points = (vertices »*» orders[-1]*(1-scaling_factor) »+» vector »reals()» «%« '%0.3f')
say ('<polygon points="' + points.join(' ') + '"/>')
}
say '</svg>' |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
* * * *
* * * * * * * *
* *
* * * *
* * * *
* * * * * * * *
* * * *
* * * * * * * *
* * * * * * * *
* * * * * * * * * * * * * * * *
Related tasks
Sierpinski triangle/Graphical for graphics images of this pattern.
Sierpinski carpet
| #Delphi | Delphi | program SierpinskiTriangle;
{$APPTYPE CONSOLE}
procedure PrintSierpinski(order: Integer);
var
x, y, size: Integer;
begin
size := (1 shl order) - 1;
for y := size downto 0 do
begin
Write(StringOfChar(' ', y));
for x := 0 to size - y do
begin
if (x and y) = 0 then
Write('* ')
else
Write(' ');
end;
Writeln;
end;
end;
begin
PrintSierpinski(4);
end. |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Quackery | Quackery | [ $ "turtleduck.qky" loadfile ] now!
[ 1 & ] is odd ( n --> b )
[ 4 times
[ 2dup walk
1 4 turn ]
2drop ] is square ( n/d --> )
[ dup
witheach
[ odd if
[ ' [ 0 0 0 ] fill
[ 2 1 square ] ]
2 1 fly ]
size -2 * 1 fly
1 4 turn
2 1 fly
-1 4 turn ] is showline ( [ --> )
[ [] 0 rot 0 join
witheach
[ tuck +
rot join swap ]
drop ] is nextline ( [ --> [ )
[ ' [ 1 ] swap
bit
1 - times
[ dup showline
nextline ]
showline ] is sierpinski ( n --> )
turtle
5 8 turn
400 1 fly
3 8 turn
8 sierpinski |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #R | R |
## Plotting Sierpinski triangle. aev 4/1/17
## ord - order, fn - file name, ttl - plot title, clr - color
pSierpinskiT <- function(ord, fn="", ttl="", clr="navy") {
m=640; abbr="STR"; dftt="Sierpinski triangle";
n=2^ord; M <- matrix(c(0), ncol=n, nrow=n, byrow=TRUE);
cat(" *** START", abbr, date(), "\n");
if(fn=="") {pf=paste0(abbr,"o", ord)} else {pf=paste0(fn, ".png")};
if(ttl!="") {dftt=ttl}; ttl=paste0(dftt,", order ", ord);
cat(" *** Plot file:", pf,".png", "title:", ttl, "\n");
for(y in 1:n) {
for(x in 1:n) {
if(bitwAnd(x, y)==0) {M[x,y]=1}
##if(bitwAnd(x, y)>0) {M[x,y]=1} ## Try this for "reversed" ST
}}
plotmat(M, pf, clr, ttl);
cat(" *** END", abbr, date(), "\n");
}
## Executing:
pSierpinskiT(6,,,"red");
pSierpinskiT(8);
|
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
######### #########
# ## ## # # ## ## #
######### #########
### ### ### ###
# # # # # # # #
### ### ### ###
######### #########
# ## ## # # ## ## #
######### #########
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ###### ###
###########################
# ## ## ## ## ## ## ## ## #
###########################
The use of the # character is not rigidly required for ASCII art.
The important requirement is the placement of whitespace and non-whitespace characters.
Related task
Sierpinski triangle
| #ALGOL_68 | ALGOL 68 | PROC in carpet = (INT in x, in y)BOOL: (
INT x := in x, y := in y;
BOOL out;
DO
IF x = 0 OR y = 0 THEN
out := TRUE; GO TO stop iteration
ELIF x MOD 3 = 1 AND y MOD 3 = 1 THEN
out := FALSE; GO TO stop iteration
FI;
x %:= 3;
y %:= 3
OD;
stop iteration: out
);
PROC carpet = (INT n)VOID:
FOR i TO 3 ** n DO
FOR j TO 3 ** n DO
IF in carpet(i-1, j-1) THEN
print("* ")
ELSE
print(" ")
FI
OD;
print(new line)
OD;
carpet(3) |
http://rosettacode.org/wiki/Shoelace_formula_for_polygonal_area | Shoelace formula for polygonal area | Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs returns the absolute value)
Task
Write a function/method/routine to use the the Shoelace formula to calculate the area of the polygon described by the ordered points:
(3,4), (5,11), (12,8), (9,5), and (5,6)
Show the answer here, on this page.
| #11l | 11l | F area_by_shoelace(x, y)
R abs(sum(zip(x, y[1..] [+] y[0.<1]).map((i, j) -> i * j))
-sum(zip(x[1..] [+] x[0.<1], y).map((i, j) -> i * j))) / 2
V points = [(3, 4), (5, 11), (12, 8), (9, 5), (5, 6)]
V x = points.map(p -> p[0])
V y = points.map(p -> p[1])
print(area_by_shoelace(x, y)) |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, baseball cards, books), a diary, an electronic organizer (birthdays/anniversaries/phone numbers/addresses), etc.
You should track the following details:
A description of the item. (e.g., title, name)
A category or tag (genre, topic, relationship such as “friend” or “family”)
A date (either the date when the entry was made or some other date that is meaningful, like the birthday); the date may be generated or entered manually
Other optional fields
The command should support the following Command-line arguments to run:
Add a new entry
Print the latest entry
Print the latest entry for each category
Print all entries sorted by a date
The category may be realized as a tag or as structure (by making all entries in that category subitems)
The file format on disk should be human readable, but it need not be standardized. A natively available format that doesn't need an external library is preferred. Avoid developing your own format if you can use an already existing one. If there is no existing format available, pick one of:
JSON
S-Expressions
YAML
others
Related task
Take notes on the command line
| #Erlang | Erlang |
#! /usr/bin/env escript
-compile({no_auto_import,[date/0]}).
main( ["add", Tag | Descriptions] ) -> add( date(), Tag, Descriptions );
main( ["add_date", Date, Tag | Descriptions] ) -> add( date_internal(string:tokens(Date, "-")), Tag, Descriptions );
main( ["print_latest"] ) -> print_latest( contents() );
main( ["print_latest_for_each"] ) -> print_latest_for_each( contents() );
main( ["print_all_date", Date] ) -> print_all_date( date_internal(string:tokens(Date, "-")), contents() );
main( _Error ) -> usage().
add( Date, Tag, Descriptions ) ->
Contents = contents(),
file:write_file( file(), io_lib:format("simple_database_v1.~n~p.~n", [[{Date, Tag, Descriptions} | Contents]]) ).
date() ->
{{Date, _Time}} = calendar:local_time(),
Date.
date_external( {Year, Month, Day} ) -> string:join( [erlang:integer_to_list(Year), erlang:integer_to_list(Month), erlang:integer_to_list(Day)], "-" );
date_external( _Error ) -> usage().
date_internal( [Year, Month, Day] ) -> {erlang:list_to_integer(Year), erlang:list_to_integer(Month), erlang:list_to_integer(Day)};
date_internal( _Error ) -> usage().
file() -> "simple_database_contents".
contents() -> contents( file:consult(file()) ).
contents( {ok, [simple_database_v1, Contents]} ) -> Contents;
contents( {error, Error} ) when is_atom(Error) -> [];
contents( {error, _Error} ) ->
io:fwrite( "Error: ~p corrupt. Starting from scratch~n", [file()] ),
[].
print_all_date( _Date, [] ) -> ok;
print_all_date( Date, Contents ) -> [print_latest([{D, Tag, Descriptions}]) || {D, Tag, Descriptions} <- Contents, D =:= Date].
print_latest( [] ) -> ok;
print_latest( [{Date, Tag, Descriptions} | _T] ) -> io:fwrite( "~s~n", [string:join( [date_external(Date), Tag | Descriptions], " ")] ).
print_latest_for_each( [] ) -> ok;
print_latest_for_each( Contents ) ->
Tags = lists:usort( [Tag || {_Date, Tag, _Descriptions} <- Contents] ),
[print_latest([lists:keyfind(X, 2, Contents)]) || X <- Tags].
usage() ->
io:fwrite( "Usage: ~p [add | add_date <date>] tag description ...~n", [escript:script_name()] ),
io:fwrite( "Or: ~p [print_latest | print_latest_for_each | print_all_date <date>]~n", [escript:script_name()] ),
io:fwrite( "Date format is YYYY-MM-DD~n" ),
io:fwrite( "Data stored in ~p~n", [file()] ),
init:stop().
|
http://rosettacode.org/wiki/Shortest_common_supersequence | Shortest common supersequence | The shortest common supersequence is a problem closely related to the longest common subsequence, which you can use as an external function for this task.
Task
Given two strings
u
{\displaystyle u}
and
v
{\displaystyle v}
, find the shortest possible sequence
s
{\displaystyle s}
, which is the shortest common super-sequence of
u
{\displaystyle u}
and
v
{\displaystyle v}
where both
u
{\displaystyle u}
and
v
{\displaystyle v}
are a subsequence of
s
{\displaystyle s}
. Defined as such,
s
{\displaystyle s}
is not necessarily unique.
Demonstrate this by printing
s
{\displaystyle s}
where
u
=
{\displaystyle u=}
“abcbdab” and
v
=
{\displaystyle v=}
“bdcaba”.
Also see
Wikipedia: shortest common supersequence
| #jq | jq | # largest common substring
# Uses recursion, taking advantage of jq's TCO
def lcs:
. as [$x, $y]
| if ($x|length == 0) or ($y|length == 0) then ""
else $x[:-1] as $x1
| $y[:-1] as $y1
| if $x[-1:] == $y[-1:] then ([$x1, $y1] | lcs) + $x[-1:]
else ([$x, $y1] | lcs) as $x2
| ([$x1, $y] | lcs) as $y2
| if ($x2|length) > ($y2|length) then $x2 else $y2 end
end
end;
def scs:
def eq($s;$i; $t;$j): $s[$i:$i+1] == $t[$j:$j+1];
. as [$u, $v]
| lcs as $lcs
| reduce range(0; $lcs|length) as $i ( { ui: 0, vi: 0, sb: "" };
until( .ui == ($u|length) or eq($u;.ui; $lcs;$i);
.ui as $ui
| .sb += $u[$ui:$ui+1]
| .ui += 1 )
| until(.vi == ($v|length) or eq($v;.vi; $lcs;$i);
.vi as $vi
| .sb += $v[$vi:$vi+1]
| .vi += 1 )
| .sb += $lcs[$i:$i+1]
| .ui += 1
| .vi += 1
)
| if .ui < ($u|length) then .sb = .sb + $u[.ui:] else . end
| if .vi < ($v|length) then .sb = .sb + $v[.vi:] else . end
| .sb ;
[ "abcbdab", "bdcaba" ] | scs |
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