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http://rosettacode.org/wiki/Haversine_formula
Haversine formula
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) The haversine formula is an equation important in navigation, g...
#Oforth
Oforth
import: math   : haversine(lat1, lon1, lat2, lon2) | lat lon |   lat2 lat1 - asRadian ->lat lon2 lon1 - asRadian ->lon   lon 2 / sin sq lat1 asRadian cos * lat2 asRadian cos * lat 2 / sin sq + sqrt asin 2 * 6372.8 * ;   haversine(36.12, -86.67, 33.94, -118.40) println
http://rosettacode.org/wiki/Haversine_formula
Haversine formula
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) The haversine formula is an equation important in navigation, g...
#ooRexx
ooRexx
/*REXX pgm calculates distance between Nashville & Los Angles airports. */ say " Nashville: north 36º 7.2', west 86º 40.2' = 36.12º, -86.67º" say "Los Angles: north 33º 56.4', west 118º 24.0' = 33.94º, -118.40º" say dist=surfaceDistance(36.12, -86.67, 33.94, -118.4) kdist=format(dist/1 ,,2) ...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#GLBasic
GLBasic
STDOUT "Hello world!"
http://rosettacode.org/wiki/Harshad_or_Niven_series
Harshad or Niven series
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits. For example,   42   is a Harshad number as   42   is divisible by   (4 + 2)   without remainder. Assume that the series is defined as the numbers in increasing order. Task The task is to create a function/method/...
#PicoLisp
PicoLisp
  #if niven number, return it. (de niven (N) (if (=0 (% N (apply + (getN N)))) N) )   #function which creates a list of numbers from input (de getN (N) (mapcar format (chop N)) )   #This function generates niven number list (de nivGen (R N) (extract niven (range R N)) )   #print 1st 20 niven numbers and 1st ni...
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#Just_Basic
Just Basic
  print "Goodbye, World!" 'Prints in the upper left corner of the default text window: mainwin, a window with scroll bars.  
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#KonsolScript
KonsolScript
function main() { Konsol:Message("Goodbye, World!", "") }
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#Ring
Ring
  Load "guilib.ring"   MyApp = New qApp { num = 0 win1 = new qWidget() { setwindowtitle("Hello World") setGeometry(100,100,370,250)   btn1 = new qpushbutton(win1) { setGeometry(200,200,100,30) settext("Random") ...
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#Ruby
Ruby
Shoes.app(title: "GUI component interaction") do stack do textbox = edit_line   textbox.change do textbox.text = textbox.text.gsub(/[^\d]/, '') and alert "Input must be a number!" if textbox.text !~ /^\d*$/ end   flow do button "Increment" do textbox.text = textbox.text.to_i + 1 ...
http://rosettacode.org/wiki/Gray_code
Gray code
Gray code Karnaugh maps Create functions to encode a number to and decode a number from Gray code. Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary). There are many possible Gray codes. The follow...
#Batch_File
Batch File
:: Gray Code Task from Rosetta Code :: Batch File Implementation   @echo off rem -------------- define batch file macros with parameters appended rem more info: https://www.dostips.com/forum/viewtopic.php?f=3&t=2518 setlocal disabledelayedexpansion % == required for macro ==% (set \n=^^^ %== this creates escaped line f...
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#Arturo
Arturo
print split.lines execute "ls"
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#AWK
AWK
  BEGIN {   # For Windows out = system2var("dir") print out   # Non-Windows out = getline2var("ls -l") print out }   # For a Windows environment using system() method function system2var(command ,tempfile, cmd, out, rec, data, i) { tempfile = "C:\\TEMP\\...
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#BaCon
BaCon
' Get system command result$ = EXEC$("fortune") PRINT CHOP$(result$) PRINT "First word: " & TOKEN$(result$, 1)
http://rosettacode.org/wiki/Generic_swap
Generic swap
Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity. If variables are typed in t...
#11l
11l
F swap(&a, &b) (a, b) = (b, a)
http://rosettacode.org/wiki/Greatest_element_of_a_list
Greatest element of a list
Task Create a function that returns the maximum value in a provided set of values, where the number of values may not be known until run-time.
#Amazing_Hopper
Amazing Hopper
  #include <hopper.h> main: lst=0 max=0 file="datos.txt"   {","} toksep {file} statsfile {file} load mov (lst) {0} reshape (lst) {lst} array (SORT) [end] get (lst) mov ...
http://rosettacode.org/wiki/Greatest_element_of_a_list
Greatest element of a list
Task Create a function that returns the maximum value in a provided set of values, where the number of values may not be known until run-time.
#AntLang
AntLang
max|range[10]
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related tas...
#ACL2
ACL2
(include-book "arithmetic-3/floor-mod/floor-mod" :dir :system)   (defun gcd$ (x y) (declare (xargs :guard (and (natp x) (natp y)))) (cond ((or (not (natp x)) (< y 0)) nil) ((zp y) x) (t (gcd$ y (mod x y)))))
http://rosettacode.org/wiki/Globally_replace_text_in_several_files
Globally replace text in several files
Task Replace every occurring instance of a piece of text in a group of text files with another one. For this task we want to replace the text   "Goodbye London!"   with   "Hello New York!"   for a list of files.
#C
C
#include <stdio.h> #include <stdlib.h> #include <stddef.h> #include <string.h> #include <sys/types.h> #include <fcntl.h> #include <sys/stat.h> #include <unistd.h> #include <err.h> #include <string.h>   char * find_match(const char *buf, const char * buf_end, const char *pat, size_t len) { ptrdiff_t i; char *start = b...
http://rosettacode.org/wiki/Hailstone_sequence
Hailstone sequence
The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 The (unproven) Collatz conje...
#ALGOL_68
ALGOL 68
MODE LINT = # LONG ... # INT;   PROC hailstone = (INT in n, REF[]LINT array)INT: ( INT hs := 1; INT index := 0; LINT n := in n;   WHILE n /= 1 DO hs +:= 1; IF array ISNT REF[]LINT(NIL) THEN array[index +:= 1] := n FI; n := IF ODD n THEN 3*n+1 ELSE n OVER 2 FI OD; IF array...
http://rosettacode.org/wiki/Grayscale_image
Grayscale image
Many image processing algorithms are defined for grayscale (or else monochromatic) images. Task Extend the data storage type defined on this page to support grayscale images. Define two operations, one to convert a color image to a grayscale image and one for the backward conversion. To get luminance of a color u...
#Go
Go
package raster   import ( "math" "math/rand" )   // Grmap parallels Bitmap, but with an element type of uint16 // in place of Pixel. type Grmap struct { Comments []string rows, cols int px []uint16 pxRow [][]uint16 }   // NewGrmap constructor. func NewGrmap(x, y int) (b *Grmap) { ...
http://rosettacode.org/wiki/Go_Fish
Go Fish
Write a program to let the user play Go Fish against a computer opponent. Use the following rules: Each player is dealt nine cards to start with. On their turn, a player asks their opponent for a given rank (such as threes or kings). A player must already have at least one card of a given rank to ask for more. If t...
#Java
Java
#!/usr/bin/perl   use strict; # https://rosettacode.org/wiki/Go_Fish use warnings; use List::Util qw( first shuffle );   my $pat = qr/[atjqk2-9]/; # ranks my $deck = join '', shuffle map { my $rank = $_; map "$rank$_", qw( S H C D ) } qw( a t j q k ), 2 .. 9;   my $mebooks = my $youbooks = 0;   my $me = substr $deck,...
http://rosettacode.org/wiki/Hamming_numbers
Hamming numbers
Hamming numbers are numbers of the form   H = 2i × 3j × 5k where i, j, k ≥ 0 Hamming numbers   are also known as   ugly numbers   and also   5-smooth numbers   (numbers whose prime divisors are less or equal to 5). Task Generate the sequence of Hamming numbers, in increasing order.   In ...
#Crystal
Crystal
require "big"   def hamming(limit) h = Array.new(limit, 1.to_big_i) # h = Array.new(limit+1, 1.to_big_i) x2, x3, x5 = 2.to_big_i, 3.to_big_i, 5.to_big_i i, j, k = 0, 0, 0 (1...limit).each do |n| # (1..limit).each do |n| h[n] = Math.min(x2, Math.min(x3, x5)) x2 = 2 * h[i += 1] if x2 == h...
http://rosettacode.org/wiki/Guess_the_number
Guess the number
Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a   "Well guessed!"   message,   a...
#Factor
Factor
  USING: io random math math.parser kernel formatting ; IN: guess-the-number   <PRIVATE   : gen-number ( -- n ) 10 random 1 + ;   : make-guess ( n -- n ? ) dup readln string>number = ;   : play-game ( n -- n ) [ make-guess ] [ "Guess a number between 1 and 10:" print flush ] do until ;   PRIVATE>   : guess-the-...
http://rosettacode.org/wiki/Guess_the_number
Guess the number
Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a   "Well guessed!"   message,   a...
#Fantom
Fantom
  class Main { public static Void main () { Str target := (1..10).random.toStr Str guess := "" while (guess != target) { echo ("Enter a guess: ") guess = Env.cur.in.readLine if (guess.trim == target) // 'trim' to remove any spaces/newline { echo ("Well guessed!") ...
http://rosettacode.org/wiki/Greatest_subsequential_sum
Greatest subsequential sum
Task Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one. An empty subsequence is considered to have the sum of   0;   thus if all elements are negative, the result must be th...
#Elixir
Elixir
defmodule Greatest do def subseq_sum(list) do list_i = Enum.with_index(list) acc = {0, 0, length(list), 0, 0} {_,max,first,last,_} = Enum.reduce(list_i, acc, fn {elm,i},{curr,max,first,last,curr_first} -> if curr < 0 do if elm > max, do: {elm, elm, i, i, curr_first}, ...
http://rosettacode.org/wiki/Greatest_subsequential_sum
Greatest subsequential sum
Task Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one. An empty subsequence is considered to have the sum of   0;   thus if all elements are negative, the result must be th...
#ERRE
ERRE
  PROGRAM MAX_SUM   DIM A%[11],B%[10],C%[4]   !$DYNAMIC DIM P%[0]   PROCEDURE MAX_SUBSEQUENCE(P%[],N%->A$) LOCAL A%,B%,I%,J%,M%,S% A%=1 FOR I%=0 TO N% DO S%=0 FOR J%=I% TO N% DO S%+=P%[J%] IF S%>M% THEN M%=S% A%=I% B%=J% ...
http://rosettacode.org/wiki/Guess_the_number/With_feedback
Guess the number/With feedback
Task Write a game (computer program) that follows the following rules: The computer chooses a number between given set limits. The player is asked for repeated guesses until the the target number is guessed correctly At each guess, the computer responds with whether the guess is: higher than the target, equal to...
#D
D
import std.stdio, std.random, std.typecons, std.conv, std.string, std.range;   void main() { immutable interval = tuple(1, 100); writefln("Guess my target number that is between " ~ "%d and %d (inclusive).\n", interval[]); immutable target = uniform!"[]"(interval[]);   foreach (immut...
http://rosettacode.org/wiki/Greyscale_bars/Display
Greyscale bars/Display
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display. For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha...
#Scala
Scala
import scala.swing._   class GreyscaleBars extends Component { override def paintComponent(g:Graphics2D)={ val barHeight=size.height>>2 for(run <- 0 to 3; colCount=8<<run){ val deltaX=size.width.toDouble/colCount val colBase=if (run%2==0) -255 else 0 for(x <- 0 until colCount){ val c...
http://rosettacode.org/wiki/Greyscale_bars/Display
Greyscale bars/Display
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display. For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha...
#Seed7
Seed7
$ include "seed7_05.s7i"; include "draw.s7i"; include "keybd.s7i";   const proc: main is func local var integer: barHeight is 0; var integer: barNumber is 0; var integer: colCount is 0; var integer: deltaX is 0; var integer: x is 0; var integer: col is 0; begin screen(640, 480); ...
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player)
Guess the number/With feedback (player)
Task Write a player for the game that follows the following rules: The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score...
#Perl
Perl
#!/usr/bin/perl   my $min = 1; my $max = 99; my $guess = int(rand $max) + $min; my $tries = 0;   print "=>> Think of a number between $min and $max and I'll guess it!\n Press <ENTER> when are you ready... ";   <STDIN>;   { do {   $tries++; print "\n=>> My guess is: $guess Is your number higher, lo...
http://rosettacode.org/wiki/Happy_numbers
Happy numbers
From Wikipedia, the free encyclopedia: A happy number is defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals   1   (where it will stay),   or it loops endlessly in a cycle which does not inclu...
#Elena
Elena
import extensions; import system'collections; import system'routines;   isHappy(int n) { auto cache := new List<int>(5); int sum := 0; int num := n; while (num != 1) { if (cache.indexOfElement:num != -1) { ^ false }; cache.append(num); while (num !...
http://rosettacode.org/wiki/Haversine_formula
Haversine formula
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) The haversine formula is an equation important in navigation, g...
#PARI.2FGP
PARI/GP
dist(th1, th2, ph)={ my(v=[cos(ph)*cos(th1)-cos(th2),sin(ph)*cos(th1),sin(th1)-sin(th2)]); asin(sqrt(norml2(v))/2) }; distEarth(th1, ph1, th2, ph2)={ my(d=12742, deg=Pi/180); \\ Authalic diameter of the Earth d*dist(th1*deg, th2*deg, (ph1-ph2)*deg) }; distEarth(36.12, -86.67, 33.94, -118.4)
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Glee
Glee
"Hello world!"
http://rosettacode.org/wiki/Harshad_or_Niven_series
Harshad or Niven series
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits. For example,   42   is a Harshad number as   42   is divisible by   (4 + 2)   without remainder. Assume that the series is defined as the numbers in increasing order. Task The task is to create a function/method/...
#PILOT
PILOT
C :n=0  :i=0 *first20 U :*harshad C :i=i+1 T :#i: #n J (i<20):*first20 C :n=1000 U :*harshad T :First Harshad number greater than 1000: #n E : *harshad C :n=n+1  :r=n  :s=0 *digit C :a=r/10  :s=s+(r-a*10)  :r=a J (r):*digit J (n<>s*(n/s)):*harshad E :
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#Kotlin
Kotlin
import java.awt.* import javax.swing.*   fun main(args: Array<String>) { JOptionPane.showMessageDialog(null, "Goodbye, World!") // in alert box with(JFrame("Goodbye, World!")) { // on title bar layout = FlowLayout() add(JButton("Goodbye, World!")) // on bu...
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#Run_BASIC
Run BASIC
dim dd$(5) ' drop down box for i = 1 to 5 dd$(i) = "Drop ";i next i value$ = "1234" notes$ = "Rosetta Code is good"   bf$ = "<SPAN STYLE='font-family:arial; font-weight:700; font-size:12pt'>"   [screen] cls html bf$;"<center><TABLE BORDER=1 CELLPADDING=0 CELLSPACING=0 bgcolor=wheat>" html "<TR align=ce...
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#Scala
Scala
import scala.swing._ import scala.swing.Swing._ import scala.swing.event._   object Interact extends SimpleSwingApplication { def top = new MainFrame { title = "Rosetta Code >>> Task: component interaction | Language: Scala"   val numberField = new TextField { text = "0" // start at 0 horizontalAl...
http://rosettacode.org/wiki/Gray_code
Gray code
Gray code Karnaugh maps Create functions to encode a number to and decode a number from Gray code. Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary). There are many possible Gray codes. The follow...
#BBC_BASIC
BBC BASIC
INSTALL @lib$+"STRINGLIB"   PRINT " Decimal Binary Gray Decoded" FOR number% = 0 TO 31 gray% = FNgrayencode(number%) PRINT number% " " FN_tobase(number%, 2, 5) ; PRINT " " FN_tobase(gray%, 2, 5) FNgraydecode(gray%) NEXT END   DEF FNgrayenco...
http://rosettacode.org/wiki/Gray_code
Gray code
Gray code Karnaugh maps Create functions to encode a number to and decode a number from Gray code. Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary). There are many possible Gray codes. The follow...
#bc
bc
scale = 0 /* to use integer division */   /* encode Gray code */ define e(i) { auto h, r   if (i <= 0) return 0 h = i / 2 r = e(h) * 2 /* recurse */ if (h % 2 != i % 2) r += 1 /* xor low bits of h, i */ return r }   /* decode Gray code */ define d(i) { auto h, r   if (i <= 0) return 0 h = d(i ...
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#Batch_File
Batch File
  @echo off setlocal enabledelayedexpansion :: Without storing the output of the command, it can be viewed by inputting the command dir   :: Storing the output of 'dir' as "line[]" containing the respective lines of output (starting at line[1]) :: Note: This method removes any empty lines from the output set tempcoun...
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#Bracmat
Bracmat
(system= .sys$(str$(!arg " > temp"))&get$(temp,STR) );
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#C
C
  #include <stdio.h> #include <stdlib.h> #include <string.h>   int main(int argc, char **argv) { if (argc < 2) return 1;   FILE *fd; fd = popen(argv[1], "r"); if (!fd) return 1;   char buffer[256]; size_t chread; /* String to store entire command contents in */ size_t comalloc = 256; ...
http://rosettacode.org/wiki/Generic_swap
Generic swap
Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity. If variables are typed in t...
#360_Assembly
360 Assembly
  SWAP CSECT , control section start BAKR 14,0 stack caller's registers LR 12,15 entry point address to reg.12 USING SWAP,12 use as base MVC A,=C'5678____' init field A MVC B,=C'____1234' i...
http://rosettacode.org/wiki/Greatest_element_of_a_list
Greatest element of a list
Task Create a function that returns the maximum value in a provided set of values, where the number of values may not be known until run-time.
#APL
APL
LIST←2 4 6 3 8 ⌈/LIST
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related tas...
#Action.21
Action!
CARD FUNC Gcd(CARD a,b) CARD tmp   IF a<b THEN tmp=a a=b b=tmp FI   WHILE b#0 DO tmp=a MOD b a=b b=tmp OD RETURN(a)   PROC Test(CARD a,b) CARD res   res=Gcd(a,b) PrintF("GCD of %I and %I is %I%E",a,b,res) RETURN   PROC Main() Test(48,18) Test(9360,12240) Test(17,19) Test(123,1...
http://rosettacode.org/wiki/Globally_replace_text_in_several_files
Globally replace text in several files
Task Replace every occurring instance of a piece of text in a group of text files with another one. For this task we want to replace the text   "Goodbye London!"   with   "Hello New York!"   for a list of files.
#C.23
C#
  using System.Collections.Generic; using System.IO;   class Program { static void Main() { var files = new List<string> { "test1.txt", "test2.txt" }; foreach (string file in files) { File.WriteAllText(file, File.ReadAllText(file).Replace("Goodbye London!"...
http://rosettacode.org/wiki/Globally_replace_text_in_several_files
Globally replace text in several files
Task Replace every occurring instance of a piece of text in a group of text files with another one. For this task we want to replace the text   "Goodbye London!"   with   "Hello New York!"   for a list of files.
#C.2B.2B
C++
#include <fstream> #include <iterator> #include <boost/regex.hpp> #include <string> #include <iostream>   int main( int argc , char *argv[ ] ) { boost::regex to_be_replaced( "Goodbye London\\s*!" ) ; std::string replacement( "Hello New York!" ) ; for ( int i = 1 ; i < argc ; i++ ) { std::ifstream infile ...
http://rosettacode.org/wiki/Hailstone_sequence
Hailstone sequence
The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 The (unproven) Collatz conje...
#ALGOL-M
ALGOL-M
  BEGIN   INTEGER N, LEN, YES, NO, LIMIT, LONGEST, NLONG;   % RETURN P MOD Q % INTEGER FUNCTION MOD(P, Q); INTEGER P, Q; BEGIN MOD := P - Q * (P / Q); END;   % COMPUTE AND OPTIONALLY DISPLAY HAILSTONE SEQUENCE FOR N. % % RETURN LENGTH OF SEQUENCE OR ZERO ON OVERFLOW. % INTEGER FUNCTION HAILSTONE(N, DISPLAY); INTEGER ...
http://rosettacode.org/wiki/Grayscale_image
Grayscale image
Many image processing algorithms are defined for grayscale (or else monochromatic) images. Task Extend the data storage type defined on this page to support grayscale images. Define two operations, one to convert a color image to a grayscale image and one for the backward conversion. To get luminance of a color u...
#Haskell
Haskell
module Bitmap.Gray(module Bitmap.Gray) where   import Bitmap import Control.Monad.ST   newtype Gray = Gray Int deriving (Eq, Ord)   instance Color Gray where luminance (Gray x) = x black = Gray 0 white = Gray 255 toNetpbm = map $ toEnum . luminance fromNetpbm = map $ Gray . fromEnum netpbmMagicN...
http://rosettacode.org/wiki/Grayscale_image
Grayscale image
Many image processing algorithms are defined for grayscale (or else monochromatic) images. Task Extend the data storage type defined on this page to support grayscale images. Define two operations, one to convert a color image to a grayscale image and one for the backward conversion. To get luminance of a color u...
#J
J
NB. converts the image to grayscale according to formula NB. L = 0.2126*R + 0.7152*G + 0.0722*B toGray=: [: <. +/ .*"1&0.2126 0.7152 0.0722   NB. converts grayscale image to the color image, with all channels equal toColor=: 3 & $"0
http://rosettacode.org/wiki/Go_Fish
Go Fish
Write a program to let the user play Go Fish against a computer opponent. Use the following rules: Each player is dealt nine cards to start with. On their turn, a player asks their opponent for a given rank (such as threes or kings). A player must already have at least one card of a given rank to ask for more. If t...
#Julia
Julia
#!/usr/bin/perl   use strict; # https://rosettacode.org/wiki/Go_Fish use warnings; use List::Util qw( first shuffle );   my $pat = qr/[atjqk2-9]/; # ranks my $deck = join '', shuffle map { my $rank = $_; map "$rank$_", qw( S H C D ) } qw( a t j q k ), 2 .. 9;   my $mebooks = my $youbooks = 0;   my $me = substr $deck,...
http://rosettacode.org/wiki/Hamming_numbers
Hamming numbers
Hamming numbers are numbers of the form   H = 2i × 3j × 5k where i, j, k ≥ 0 Hamming numbers   are also known as   ugly numbers   and also   5-smooth numbers   (numbers whose prime divisors are less or equal to 5). Task Generate the sequence of Hamming numbers, in increasing order.   In ...
#D
D
import std.stdio, std.bigint, std.algorithm, std.range, core.memory;   auto hamming(in uint n) pure nothrow /*@safe*/ { immutable BigInt two = 2, three = 3, five = 5; auto h = new BigInt[n]; h[0] = 1; BigInt x2 = 2, x3 = 3, x5 = 5; size_t i, j, k;   foreach (ref el; h.dropOne) { el = min...
http://rosettacode.org/wiki/Guess_the_number
Guess the number
Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a   "Well guessed!"   message,   a...
#Forth
Forth
  \ tested with GForth 0.7.0 : RND ( -- n) TIME&DATE 2DROP 2DROP DROP 10 MOD ; \ crude random number : ASK ( -- ) CR ." Guess a number between 1 and 10? " ; : GUESS ( -- n) PAD DUP 4 ACCEPT EVALUATE ; : REPLY ( n n' -- n) 2DUP <> IF CR ." No, it's not " DUP . THEN ;   : GAME ( -- ) RND ...
http://rosettacode.org/wiki/Guess_the_number
Guess the number
Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a   "Well guessed!"   message,   a...
#Fortran
Fortran
program guess_the_number implicit none   integer :: guess real :: r integer :: i, clock, count, n integer,dimension(:),allocatable :: seed   real,parameter :: rmax = 10   !initialize random number generator: call random_seed(size=n) ...
http://rosettacode.org/wiki/Greatest_subsequential_sum
Greatest subsequential sum
Task Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one. An empty subsequence is considered to have the sum of   0;   thus if all elements are negative, the result must be th...
#Euler_Math_Toolbox
Euler Math Toolbox
  >function %maxsubs (v,n) ... $if n==1 then $ if (v[1]<0) then return {zeros(1,0),zeros(1,0)} $ else return {v,v}; $ endif; $endif; ${v1,v2}=%maxsubs(v[1:n-1],n-1); $m1=sum(v1); m2=sum(v2); m3=m2+v[n]; $if m3>0 then v3=v2|v[n]; else v3=zeros(1,0); endif; $if m3>m1 then return {v2|v[n],v3}; $else return {v1,v3}; ...
http://rosettacode.org/wiki/Greatest_subsequential_sum
Greatest subsequential sum
Task Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one. An empty subsequence is considered to have the sum of   0;   thus if all elements are negative, the result must be th...
#Euphoria
Euphoria
function maxSubseq(sequence s) integer sum, maxsum, first, last maxsum = 0 first = 1 last = 0 for i = 1 to length(s) do sum = 0 for j = i to length(s) do sum += s[j] if sum > maxsum then maxsum = sum first = i la...
http://rosettacode.org/wiki/Guess_the_number/With_feedback
Guess the number/With feedback
Task Write a game (computer program) that follows the following rules: The computer chooses a number between given set limits. The player is asked for repeated guesses until the the target number is guessed correctly At each guess, the computer responds with whether the guess is: higher than the target, equal to...
#DCL
DCL
$ rnd = f$extract( 21, 2, f$time() ) $ count = 0 $ loop: $ inquire guess "guess what number between 0 and 99 inclusive I am thinking of" $ guess = f$integer( guess ) $ if guess .lt. 0 .or. guess .gt. 99 $ then $ write sys$output "out of range" $ goto loop $ endif $ count = count + 1 $ if guess .lt. rnd then $ write s...
http://rosettacode.org/wiki/Greyscale_bars/Display
Greyscale bars/Display
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display. For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha...
#Tcl
Tcl
package require Tcl 8.5 package require Tk 8.5   wm attributes . -fullscreen 1 pack [canvas .c -highlightthick 0] -fill both -expand 1   # Add more values into this to do more greyscale bar variations set splits {8 16 32 64} set dy [expr {[winfo screenheight .c] / [llength $splits]}] set y 0 foreach s $splits { set...
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player)
Guess the number/With feedback (player)
Task Write a player for the game that follows the following rules: The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score...
#Phix
Phix
-- -- demo\rosetta\Guess_the_number2.exw -- with javascript_semantics -- (spacing not (yet) great...) include pGUI.e Ihandle lbl, guess, toohigh, too_low, correct, newgame, dlg integer Min=0, Max=100, Guess constant LTHINK = sprintf("Think of a number between %d and %d.",{Min,Max}) procedure set_active(bool bActive) ...
http://rosettacode.org/wiki/Happy_numbers
Happy numbers
From Wikipedia, the free encyclopedia: A happy number is defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals   1   (where it will stay),   or it loops endlessly in a cycle which does not inclu...
#Elixir
Elixir
defmodule Happy do def task(num) do Process.put({:happy, 1}, true) Stream.iterate(1, &(&1+1)) |> Stream.filter(fn n -> happy?(n) end) |> Enum.take(num) end   defp happy?(n) do sum = square_sum(n, 0) val = Process.get({:happy, sum}) if val == nil do Process.put({:happy, sum}, fals...
http://rosettacode.org/wiki/Haversine_formula
Haversine formula
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) The haversine formula is an equation important in navigation, g...
#Pascal
Pascal
Program HaversineDemo(output);   uses Math;   function haversineDist(th1, ph1, th2, ph2: double): double; const diameter = 2 * 6372.8; var dx, dy, dz: double; begin ph1 := degtorad(ph1 - ph2); th1 := degtorad(th1); th2 := degtorad(th2);   dz := sin(th1) - sin(th2); dx := cos(ph1) * co...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Global_Script
Global Script
λ _. print qq{Hello world!\n}
http://rosettacode.org/wiki/Harshad_or_Niven_series
Harshad or Niven series
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits. For example,   42   is a Harshad number as   42   is divisible by   (4 + 2)   without remainder. Assume that the series is defined as the numbers in increasing order. Task The task is to create a function/method/...
#PL.2FI
PL/I
*process source or(!) xref attributes; niven: Proc Options(main); /********************************************************************* * 08-06.2013 Walter Pachl translated from Rexx * with a slight improvement: Do j=y+1 By 1; **************************************************************...
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#LabVIEW
LabVIEW
sys_process('/usr/bin/osascript', (: '-e', 'display dialog "Goodbye, World!"'))->wait
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#Lasso
Lasso
sys_process('/usr/bin/osascript', (: '-e', 'display dialog "Goodbye, World!"'))->wait
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#Smalltalk
Smalltalk
|top input vh incButton rndButton|   vh := ValueHolder with:0.   top := StandardSystemView label:'Rosetta GUI interaction'. top extent:300@100. top add:((Label label:'Value:') origin: 0 @ 10 corner: 100 @ 40). top add:(input := EditField origin: 102 @ 10 corner: 1.0 @ 40). input model:(TypeConverter onNumberValue:vh). ...
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#Tcl
Tcl
package require Tk   ###--- Our data Model! ---### # A single variable will do just fine set field 0   ###--- Lay out the GUI components in our View ---### # We use the Ttk widget set here; it looks much better on Windows and OSX   # First, a quick hack to make things look even nicer place [ttk::frame .bg] -relwidth 1 ...
http://rosettacode.org/wiki/Gray_code
Gray code
Gray code Karnaugh maps Create functions to encode a number to and decode a number from Gray code. Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary). There are many possible Gray codes. The follow...
#C
C
int gray_encode(int n) { return n ^ (n >> 1); }   int gray_decode(int n) { int p = n; while (n >>= 1) p ^= n; return p; }
http://rosettacode.org/wiki/Gray_code
Gray code
Gray code Karnaugh maps Create functions to encode a number to and decode a number from Gray code. Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary). There are many possible Gray codes. The follow...
#C.23
C#
using System;   public class Gray { public static ulong grayEncode(ulong n) { return n^(n>>1); }   public static ulong grayDecode(ulong n) { ulong i=1<<8*64-2; //long is 64-bit ulong p, b=p=n&i;   while((i>>=1)>0) b|=p=n&i^p>>1; return b; }   publi...
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#C.23
C#
using System;   namespace GetSystemCommandOutput { class Program { static void Main(string[] args) { System.Diagnostics.Process process = new System.Diagnostics.Process(); System.Diagnostics.ProcessStartInfo startInfo = new System.Diagnostics.ProcessStartInfo(); startInfo...
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#C.2B.2B
C++
#include <fstream> #include <iostream>   std::string execute(const std::string& command) { system((command + " > temp.txt").c_str());   std::ifstream ifs("temp.txt"); std::string ret{ std::istreambuf_iterator<char>(ifs), std::istreambuf_iterator<char>() }; ifs.close(); // must close the inout stream so ...
http://rosettacode.org/wiki/Generic_swap
Generic swap
Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity. If variables are typed in t...
#6502_Assembly
6502 Assembly
;swap X with Y pha  ;push accumulator txa pha  ;push x tya pha ;push y pla tax ;pop y into x pla tay  ;pop x into y pla  ;pop accumulator
http://rosettacode.org/wiki/Greatest_element_of_a_list
Greatest element of a list
Task Create a function that returns the maximum value in a provided set of values, where the number of values may not be known until run-time.
#AppleScript
AppleScript
  max({1, 2, 3, 4, 20, 6, 11, 3, 9, 7})   on max(aList) set _curMax to first item of aList repeat with i in (rest of aList) if i > _curMax then set _curMax to contents of i end repeat return _curMax end max  
http://rosettacode.org/wiki/Greatest_common_divisor
Greatest common divisor
Greatest common divisor You are encouraged to solve this task according to the task description, using any language you may know. Task Find the greatest common divisor   (GCD)   of two integers. Greatest common divisor   is also known as   greatest common factor (gcf)   and   greatest common measure. Related tas...
#ActionScript
ActionScript
//Euclidean algorithm function gcd(a:int,b:int):int { var tmp:int; //Swap the numbers so a >= b if(a < b) { tmp = a; a = b; b = tmp; } //Find the gcd while(b != 0) { tmp = a % b; a = b; b = tmp; } return a; }
http://rosettacode.org/wiki/Globally_replace_text_in_several_files
Globally replace text in several files
Task Replace every occurring instance of a piece of text in a group of text files with another one. For this task we want to replace the text   "Goodbye London!"   with   "Hello New York!"   for a list of files.
#Clojure
Clojure
(defn hello-goodbye [& more] (doseq [file more] (spit file (.replace (slurp file) "Goodbye London!" "Hello New York!"))))
http://rosettacode.org/wiki/Globally_replace_text_in_several_files
Globally replace text in several files
Task Replace every occurring instance of a piece of text in a group of text files with another one. For this task we want to replace the text   "Goodbye London!"   with   "Hello New York!"   for a list of files.
#Common_Lisp
Common Lisp
  (defun hello-goodbye (files) (labels ((replace-from-file (file) (with-open-file (in file) (loop for line = (read-line in nil) while line do (loop for index = (search "Goodbye London!" line) while index do ...
http://rosettacode.org/wiki/Hailstone_sequence
Hailstone sequence
The Hailstone sequence of numbers can be generated from a starting positive integer,   n   by:   If   n   is     1     then the sequence ends.   If   n   is   even then the next   n   of the sequence   = n/2   If   n   is   odd   then the next   n   of the sequence   = (3 * n) + 1 The (unproven) Collatz conje...
#ALGOL_W
ALGOL W
begin  % show some Hailstone Sequence related information  %  % calculates the length of the sequence generated by n,  %  % if showFirstAndLast is true, the first and last 4 elements of the  %  % sequence are stored in first and last  ...
http://rosettacode.org/wiki/Grayscale_image
Grayscale image
Many image processing algorithms are defined for grayscale (or else monochromatic) images. Task Extend the data storage type defined on this page to support grayscale images. Define two operations, one to convert a color image to a grayscale image and one for the backward conversion. To get luminance of a color u...
#Java
Java
void convertToGrayscale(final BufferedImage image){ for(int i=0; i<image.getWidth(); i++){ for(int j=0; j<image.getHeight(); j++){ int color = image.getRGB(i,j);   int alpha = (color >> 24) & 255; int red = (color >> 16) & 255; int green = (color >> 8) & 255; ...
http://rosettacode.org/wiki/Grayscale_image
Grayscale image
Many image processing algorithms are defined for grayscale (or else monochromatic) images. Task Extend the data storage type defined on this page to support grayscale images. Define two operations, one to convert a color image to a grayscale image and one for the backward conversion. To get luminance of a color u...
#JavaScript
JavaScript
  function toGray(img) { let cnv = document.getElementById("canvas"); let ctx = cnv.getContext('2d'); let imgW = img.width; let imgH = img.height; cnv.width = imgW; cnv.height = imgH;   ctx.drawImage(img, 0, 0); let pixels = ctx.getImageData(0, 0, imgW, imgH); for (let y = 0; y < pixels.height; y ++) ...
http://rosettacode.org/wiki/Go_Fish
Go Fish
Write a program to let the user play Go Fish against a computer opponent. Use the following rules: Each player is dealt nine cards to start with. On their turn, a player asks their opponent for a given rank (such as threes or kings). A player must already have at least one card of a given rank to ask for more. If t...
#Kotlin
Kotlin
#!/usr/bin/perl   use strict; # https://rosettacode.org/wiki/Go_Fish use warnings; use List::Util qw( first shuffle );   my $pat = qr/[atjqk2-9]/; # ranks my $deck = join '', shuffle map { my $rank = $_; map "$rank$_", qw( S H C D ) } qw( a t j q k ), 2 .. 9;   my $mebooks = my $youbooks = 0;   my $me = substr $deck,...
http://rosettacode.org/wiki/Hamming_numbers
Hamming numbers
Hamming numbers are numbers of the form   H = 2i × 3j × 5k where i, j, k ≥ 0 Hamming numbers   are also known as   ugly numbers   and also   5-smooth numbers   (numbers whose prime divisors are less or equal to 5). Task Generate the sequence of Hamming numbers, in increasing order.   In ...
#Dart
Dart
import 'dart:math';   final lb2of2 = 1.0; final lb2of3 = log(3.0) / log(2.0); final lb2of5 = log(5.0) / log(2.0);   class Trival { final double log2; final int twos; final int threes; final int fives; Trival mul2() { return Trival(this.log2 + lb2of2, this.twos + 1, this.threes, this.fives); } Trival m...
http://rosettacode.org/wiki/Guess_the_number
Guess the number
Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a   "Well guessed!"   message,   a...
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   Randomize Dim n As Integer = Int(Rnd * 10) + 1 Dim guess As Integer Print "Guess which number I've chosen in the range 1 to 10" Print Do Input " Your guess : "; guess If n = guess Then Print "Well guessed!" End End If Loop
http://rosettacode.org/wiki/Guess_the_number
Guess the number
Task Write a program where the program chooses a number between   1   and   10. A player is then prompted to enter a guess.   If the player guesses wrong,   then the prompt appears again until the guess is correct. When the player has made a successful guess the computer will issue a   "Well guessed!"   message,   a...
#Frink
Frink
// Guess a Number target = random[1,10] // Min and max are both inclusive for the random function guess = 0 println["Welcome to guess a number! I've picked a number between 1 and 10. Try to guess it!"] while guess != target { guessStr = input["What is your guess?"] guess = parseInt[guessStr] if guess == undef ...
http://rosettacode.org/wiki/Greatest_subsequential_sum
Greatest subsequential sum
Task Given a sequence of integers, find a continuous subsequence which maximizes the sum of its elements, that is, the elements of no other single subsequence add up to a value larger than this one. An empty subsequence is considered to have the sum of   0;   thus if all elements are negative, the result must be th...
#F.23
F#
let maxsubseq s = let (_, _, maxsum, maxseq) = List.fold (fun (sum, seq, maxsum, maxseq) x -> let (sum, seq) = (sum + x, x :: seq) if sum < 0 then (0, [], maxsum, maxseq) else if sum > maxsum then (sum, seq, sum, seq) else (sum, seq, maxsum, maxseq)) ...
http://rosettacode.org/wiki/Guess_the_number/With_feedback
Guess the number/With feedback
Task Write a game (computer program) that follows the following rules: The computer chooses a number between given set limits. The player is asked for repeated guesses until the the target number is guessed correctly At each guess, the computer responds with whether the guess is: higher than the target, equal to...
#Delphi
Delphi
program GuessTheNumber;   {$APPTYPE CONSOLE}   uses SysUtils, Math;     const // Set min/max limits min: Integer = 1; max: Integer = 10;   var last, val, inp: Integer; s: string;   // Initialise new game procedure NewGame; begin // Make sure this number isn't the same as the last one rep...
http://rosettacode.org/wiki/Greyscale_bars/Display
Greyscale bars/Display
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display. For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha...
#Wren
Wren
import "graphics" for Canvas, Color import "dome" for Window import "math" for Math   class GreyBars { construct new(width, height) { Window.title = "Grey bars example" Window.resize(width, height) Canvas.resize(width, height) _w = width _h = height }   init() { ...
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player)
Guess the number/With feedback (player)
Task Write a player for the game that follows the following rules: The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score...
#PicoLisp
PicoLisp
(de guessTheNumber (Min Max) (prinl "Think of a number between " Min " and " Max ".") (prinl "On every guess of mine you should state whether my guess was") (prinl "too high, too low, or equal to your number by typing 'h', 'l', Or '='") (use Guess (loop (NIL (> Max Min) (prinl "I ...
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player)
Guess the number/With feedback (player)
Task Write a player for the game that follows the following rules: The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score...
#Prolog
Prolog
min(1). max(10).   pick_number(Min, Max) :- min(Min), max(Max), format('Pick a number between ~d and ~d, and I will guess it...~nReady? (Enter anything when ready):', [Min, Max]), read(_).   guess_number(Min, Max) :- Guess is (Min + Max) // 2, format('I guess ~d...~nAm I correct (c), too low (l), or...
http://rosettacode.org/wiki/Happy_numbers
Happy numbers
From Wikipedia, the free encyclopedia: A happy number is defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals   1   (where it will stay),   or it loops endlessly in a cycle which does not inclu...
#Erlang
Erlang
-module(tasks). -export([main/0]). -import(lists, [map/2, member/2, sort/1, sum/1]).   is_happy(X, XS) -> if X == 1 -> true; X < 1 -> false; true -> case member(X, XS) of true -> false; false -> is_happy(sum(map(fun(Z) -> Z*Z end, [Y - 48 || Y <- integer_to_list(X)])), ...
http://rosettacode.org/wiki/Haversine_formula
Haversine formula
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) The haversine formula is an equation important in navigation, g...
#Perl
Perl
use ntheory qw/Pi/;   sub asin { my $x = shift; atan2($x, sqrt(1-$x*$x)); }   sub surfacedist { my($lat1, $lon1, $lat2, $lon2) = @_; my $radius = 6372.8; my $radians = Pi() / 180;; my $dlat = ($lat2 - $lat1) * $radians; my $dlon = ($lon2 - $lon1) * $radians; $lat1 *= $radians; $lat2 *= $radians; my $a =...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#GlovePIE
GlovePIE
debug="Hello world!"
http://rosettacode.org/wiki/Harshad_or_Niven_series
Harshad or Niven series
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits. For example,   42   is a Harshad number as   42   is divisible by   (4 + 2)   without remainder. Assume that the series is defined as the numbers in increasing order. Task The task is to create a function/method/...
#PL.2FM
PL/M
100H:   /* FIND THE SUM OF THE DIGITS OF A 16-BIT NUMBER */ DIGIT$SUM: PROCEDURE(N) BYTE; DECLARE N ADDRESS, SUM BYTE; SUM = 0; DO WHILE N > 0; SUM = SUM + (N MOD 10); N = N / 10; END; RETURN SUM; END DIGIT$SUM;   /* FIND THE NEXT HARSHAD NUMBER ABOVE N */ NEXT$HARSHAD: PROCEDURE(N) ...
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#Liberty_BASIC
Liberty BASIC
NOTICE "Goodbye, world!"
http://rosettacode.org/wiki/Hello_world/Graphical
Hello world/Graphical
Task Display the string       Goodbye, World!       on a GUI object   (alert box, plain window, text area, etc.). Related task   Hello world/Text
#Lingo
Lingo
_player.alert("Goodbye, World!")
http://rosettacode.org/wiki/GUI_component_interaction
GUI component interaction
Almost every application needs to communicate with the user in some way. Therefore, a substantial part of the code deals with the interaction of program logic with GUI components. Typically, the following is needed: put values into input fields under program control read and check input from the user pop up dial...
#Vala
Vala
bool validate_input(Gtk.Window window, string str){ int64 val; bool ret = int64.try_parse(str,out val);;   if(!ret){ var dialog = new Gtk.MessageDialog(window, Gtk.DialogFlags.MODAL, Gtk.MessageType.ERROR, ...
http://rosettacode.org/wiki/Gray_code
Gray code
Gray code Karnaugh maps Create functions to encode a number to and decode a number from Gray code. Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary). There are many possible Gray codes. The follow...
#C.2B.2B
C++
  #include <bitset> #include <iostream> #include <string> #include <assert.h>   uint32_t gray_encode(uint32_t b) { return b ^ (b >> 1); }   uint32_t gray_decode(uint32_t g) { for (uint32_t bit = 1U << 31; bit > 1; bit >>= 1) { if (g & bit) g ^= bit >> 1; } return g; }   std::string to_binary...
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#Clojure
Clojure
(use '[clojure.java.shell :only [sh]]) (sh "echo" "Hello")
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#Common_Lisp
Common Lisp
(trivial-shell:shell-command "uname -imp")
http://rosettacode.org/wiki/Get_system_command_output
Get system command output
Task Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.). Related task Execute a system command
#D
D
import std.process; import std.stdio;   void main() { auto cmd = executeShell("echo hello");   if (cmd.status == 0) { writeln("Output: ", cmd.output); } else { writeln("Failed to execute command, status=", cmd.status); } }
http://rosettacode.org/wiki/Generic_swap
Generic swap
Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity. If variables are typed in t...
#68000_Assembly
68000 Assembly
EXG D0,D1 ;swap the contents of D0 and D1 EXG A0,A1 ;swap the contents of A0 and A1
http://rosettacode.org/wiki/Greatest_element_of_a_list
Greatest element of a list
Task Create a function that returns the maximum value in a provided set of values, where the number of values may not be known until run-time.
#Applesoft_BASIC
Applesoft BASIC
100 REMMAX 110 R$ = "":E$ = "" 120 L = LEN (L$) 130 IF L = 0 THEN RETURN 140 FOR I = 1 TO L 150 C$ = MID$ (L$,I,1) 160 SP = C$ = " " 170 IF SP THEN GOSUB 200 180 E$ = E$ + C$ 190 NEXT I 200 C$ = "" 210 IF E$ = "" THEN RETURN 220 V = VAL (E$):V$ = R$ 230 E$ = "":E = V$ = "" 240 IF E ...