mlfoundations-dev/load_in_code_rosetta · Data Studio

task_url stringlengths 30 116	task_name stringlengths 2 86	task_description stringlengths 0 14.4k	language_url stringlengths 2 53	language_name stringlengths 1 52	code stringlengths 0 61.9k	instruction_seed stringlengths 27 14.4k	_source stringclasses 1 value
http://rosettacode.org/wiki/Arithmetic-geometric_mean	Arithmetic-geometric mean	This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. 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) Task Write a function to compute the arithmetic-geomet...	#ZX_Spectrum_Basic	ZX Spectrum Basic	10 LET a=1: LET g=1/SQR 2 20 LET ta=a 30 LET a=(a+g)/2 40 LET g=SQR (ta*g) 50 IF a<ta THEN GO TO 20 60 PRINT a	Give a code snippet in #ZX_Spectrum_Basic This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. 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) Task Write ...	christopher/rosetta-code
http://rosettacode.org/wiki/Josephus_problem	Josephus problem	Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\displaystyle 0} , removing eve...	#Perl	Perl	my @prisoner = 0 .. 40; my $k = 3; until (@prisoner == 1) { push @prisoner, shift @prisoner for 1 .. $k-1; shift @prisoner; } print "Prisoner @prisoner survived.\n"	Give a code snippet in #Perl Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\d...	christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort	Sorting algorithms/Quicksort	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#Curry	Curry	-- quicksort using higher-order functions: qsort :: [Int] -> [Int] qsort [] = [] qsort (x:l) = qsort (filter (<x) l) ++ x : qsort (filter (>=x) l) goal = qsort [2,3,1,0]	Give a code snippet in #Curry Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick so...	christopher/rosetta-code
http://rosettacode.org/wiki/Bitwise_operations	Bitwise operations	Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic \| Comparison Boolean Operations Bitwise \| Logical String Operations Concatenation \| Interpolation \|...	#Standard_ML	Standard ML	fun bitwise_ints (a, b) = ( print ("a and b: " ^ IntInf.toString (IntInf.andb (IntInf.fromInt a, IntInf.fromInt b)) ^ "\n"); print ("a or b: " ^ IntInf.toString (IntInf.orb (IntInf.fromInt a, IntInf.fromInt b)) ^ "\n"); print ("a xor b: " ^ IntInf.toString (IntInf.xorb (IntInf.fromInt a, IntInf.fromInt b)) ^ "\...	Give a code snippet in #Standard_ML Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic \| Comparison Boolean Operations Bitwise \| Logical String Opera...	christopher/rosetta-code
http://rosettacode.org/wiki/Fractran	Fractran	FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway. A FRACTRAN program is an ordered list of positive fractions P = ( f 1 , f 2 , … , f m ) {\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})} , together with an initial positive integer input n ...	#OCaml	OCaml	open Num let get_input () = num_of_int ( try int_of_string Sys.argv.(1) with _ -> 10) let get_max_steps () = try int_of_string Sys.argv.(2) with _ -> 50 let read_program () = let line = read_line () in let words = Str.split (Str.regexp " +") line in List.map num_of_string words let i...	Give a code snippet in #OCaml FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway. A FRACTRAN program is an ordered list of positive fractions P = ( f 1 , f 2 , … , f m ) {\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})} , together with an initia...	christopher/rosetta-code
http://rosettacode.org/wiki/XML/Output	XML/Output	Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks. All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> element. As an example, calling ...	#OCaml	OCaml	# #directory "+xml-light" (* or maybe "+site-lib/xml-light" *) ;; # #load "xml-light.cma" ;; # let data = [ ("April", "Bubbly: I'm > Tam and <= Emily"); ("Tam O'Shanter", "Burns: \"When chapman billies leave the street ...\""); ("Emily", "Short & shrift"); ] in let tags = List.map (fun (name, co...	Give a code snippet in #OCaml Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks. All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> el...	christopher/rosetta-code
http://rosettacode.org/wiki/Dijkstra%27s_algorithm	Dijkstra's algorithm	This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro...	#Sidef	Sidef	class Graph(*args) { struct Node { String name, Array edges = [], Number dist = Inf, prev = nil, Bool visited = false, } struct Edge { Number weight, Node vertex, } has g = Hash() method init { args.each { \|a\| se...	Give a code snippet in #Sidef This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the ...	christopher/rosetta-code
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously	Loop over multiple arrays simultaneously	Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: ...	#Picat	Picat	import util. go => L1 = ["a","b","c"], L2 = ["A","B","C"], L3 = ["1","2","3"], println("foreach loop:"), foreach({A,B,C} in zip(L1,L2,L3)) println([A,B,C].join('')) end, nl, println("list comprehension/n:"), println( [[A,B,C].join('') : {A,B,C} in zip(L1,L2,L3)].join("\n")), nl, % W...	Give a code snippet in #Picat Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this exam...	christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Bogosort	Sorting algorithms/Bogosort	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#Modula-3	Modula-3	MODULE Bogo EXPORTS Main; IMPORT IO, Fmt, Random; VAR a := ARRAY [1..5] OF INTEGER {1, 2, 3, 4, 5}; count := 0; PROCEDURE Shuffle(VAR a: ARRAY OF INTEGER) = VAR temp: INTEGER; BEGIN WITH rand = NEW(Random.Default).init() DO FOR i := FIRST(a) TO LAST(a) - 1 DO WITH j = rand.integer(i, LAS...	Give a code snippet in #Modula-3 Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick...	christopher/rosetta-code
http://rosettacode.org/wiki/Reverse_a_string	Reverse a string	Task Take a string and reverse it. For example, "asdf" becomes "fdsa". Extra credit Preserve Unicode combining characters. For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa". Other tasks related to string operations: Metrics Array length String length Copy a string Empty string (assignment) Counting ...	#Delphi	Delphi	function ReverseString(const InString: string): string; var i: integer; begin for i := Length(InString) downto 1 do Result := Result + InString[i]; end;	Give a code snippet in #Delphi Task Take a string and reverse it. For example, "asdf" becomes "fdsa". Extra credit Preserve Unicode combining characters. For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa". Other tasks related to string operations: Metrics Array length String length Copy a string Empt...	christopher/rosetta-code
http://rosettacode.org/wiki/Fork	Fork	Task Spawn a new process which can run simultaneously with, and independently of, the original parent process.	#DCL	DCL	$! looper.com procedure $ i = 10 $ loop: $ show time $ wait 'p1 $ i = i - 1 $ if i .gt. 0 then $ goto loop	Give a code snippet in #DCL Task Spawn a new process which can run simultaneously with, and independently of, the original parent process.	christopher/rosetta-code
http://rosettacode.org/wiki/Sum_and_product_of_an_array	Sum and product of an array	Task Compute the sum and product of an array of integers.	#Sidef	Sidef	var ary = [1, 2, 3, 4, 5]; say ary.sum; # => 15 say ary.prod; # => 120	Give a code snippet in #Sidef Task Compute the sum and product of an array of integers.	christopher/rosetta-code
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...	#Elixir	Elixir	defmodule Gray_code do use Bitwise def encode(n), do: bxor(n, bsr(n,1)) def decode(g), do: decode(g,0) def decode(0,n), do: n def decode(g,n), do: decode(bsr(g,1), bxor(g,n)) end Enum.each(0..31, fn(n) -> g = Gray_code.encode(n) d = Gray_code.decode(g) :io.fwrite("~2B : ~5.2.0B : ~5.2.0B : ~5.2.0B...	Give a code snippet in #Elixir 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...	christopher/rosetta-code
http://rosettacode.org/wiki/Loops/For	Loops/For	“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code. Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers. ...	#Zig	Zig	const std = @import("std"); pub fn main() !void { const stdout_wr = std.io.getStdOut().writer(); var i: u8 = 1; while (i < 5) : (i += 1) { var j: u8 = 1; while (j <= i) : (j += 1) try stdout_wr.writeAll("*"); try stdout_wr.writeAll("\n"); } }	Give a code snippet in #Zig “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code. Common extensions of this allow other counting patterns or iterating over abstract structure...	christopher/rosetta-code
http://rosettacode.org/wiki/Execute_HQ9%2B	Execute HQ9+	Task Implement a HQ9+ interpreter or compiler.	#MiniScript	MiniScript	code = input("Enter HQ9+ program: ") sing = function() for i in range(99,2) print i + " bottles of beer on the wall, " + i + " bottles of beer" print "Take one down, pass it around, " + (i-1) + " bottle" + "s"*(i>2) + " of beer on the wall" end for print "1 bottle of beer on the wall, 1 bo...	Give a code snippet in #MiniScript Task Implement a HQ9+ interpreter or compiler.	christopher/rosetta-code
http://rosettacode.org/wiki/Trigonometric_functions	Trigonometric functions	Task If your language has a library or built-in functions for trigonometry, show examples of: sine cosine tangent inverses (of the above) using the same angle in radians and degrees. For the non-inverse functions, each radian/degree pair should use arguments that evaluate to the same angle (that i...	#Axe	Axe	Disp sin(43)▶Dec,i Disp cos(43)▶Dec,i Disp tan⁻¹(10,10)▶Dec,i	Give a code snippet in #Axe Task If your language has a library or built-in functions for trigonometry, show examples of: sine cosine tangent inverses (of the above) using the same angle in radians and degrees. For the non-inverse functions, each radian/degree pair should use arguments that evaluat...	christopher/rosetta-code
http://rosettacode.org/wiki/Loops/Infinite	Loops/Infinite	Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within l...	#AutoHotkey	AutoHotkey	Loop MsgBox SPAM `n	Give a code snippet in #AutoHotkey Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach ...	christopher/rosetta-code
http://rosettacode.org/wiki/String_matching	String matching	Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic \| Comparison Boolean Operations Bitwise \| Logical String Operations Concatenation \| Interpolation \|...	#D	D	void main() { import std.stdio; import std.algorithm: startsWith, endsWith, find, countUntil; "abcd".startsWith("ab").writeln; // true "abcd".endsWith("zn").writeln; // false "abab".find("bb").writeln; // empty array (no match) "abcd".find("bc").writeln; // "b...	Give a code snippet in #D Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic \| Comparison Boolean Operations Bitwise \| Logical String Operations Conc...	christopher/rosetta-code
http://rosettacode.org/wiki/Mutual_recursion	Mutual recursion	Two functions are said to be mutually recursive if the first calls the second, and in turn the second calls the first. Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as: F ( 0 ) = 1 ; M ( 0 ) = 0 F ( n ) = n − M ( F ( n − 1 ) ) , ...	#CoffeeScript	CoffeeScript	F = (n) -> if n is 0 then 1 else n - M F n - 1 M = (n) -> if n is 0 then 0 else n - F M n - 1 console.log [0...20].map F console.log [0...20].map M	Give a code snippet in #CoffeeScript Two functions are said to be mutually recursive if the first calls the second, and in turn the second calls the first. Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as: F ( 0 ) = 1 ; M ( 0 ) = 0 ...	christopher/rosetta-code
http://rosettacode.org/wiki/Sequence_of_non-squares	Sequence of non-squares	Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for n in the range 1 to 22 Show that no squares occur for n less than one million This is sequence A000037 in the OEIS database.	#Nim	Nim	import math, strutils func nosqr(n: int): seq[int] = result = newSeq[int](n) for i in 1..n: result[i - 1] = i + i.float.sqrt.toInt func issqr(n: int): bool = sqrt(float(n)).splitDecimal().floatpart < 1e-7 echo "Sequence for n = 22:" echo nosqr(22).join(" ") for i in nosqr(1_000_000 - 1): assert no...	Give a code snippet in #Nim Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for n in the range 1 to 22 Show that no squares occur for n less than one million This is sequence A000037 ...	christopher/rosetta-code
http://rosettacode.org/wiki/Loops/Increment_loop_index_within_loop_body	Loops/Increment loop index within loop body	Sometimes, one may need (or want) a loop which its iterator (the index variable) is modified within the loop body in addition to the normal incrementation by the (do) loop structure index. Goal Demonstrate the best way to accomplish this. Task Write a loop which: starts the index (variable...	#C.2B.2B	C++	#include "stdafx.h" #include <iostream> #include <math.h> using namespace std; bool isPrime(double number) { for (double i = number - 1; i >= 2; i--) { if (fmod(number, i) == 0) return false; } return true; } int main() { double i = 42; int n = 0; while (n < 42) { ...	Give a code snippet in #C.2B.2B Sometimes, one may need (or want) a loop which its iterator (the index variable) is modified within the loop body in addition to the normal incrementation by the (do) loop structure index. Goal Demonstrate the best way to accomplish this. Task Write a loop whic...	christopher/rosetta-code
http://rosettacode.org/wiki/Juggler_sequence	Juggler sequence	Background of the juggler sequence: Juggler sequences were publicized by an American mathematician and author Clifford A. Pickover. The name of the sequence gets it's name from the similarity of the rising and falling nature of the numbers in the sequences, much like balls in the hands of a juggler. Descrip...	#Haskell	Haskell	import Text.Printf import Data.List juggler :: Integer -> [Integer] juggler = takeWhile (> 1) . iterate (\x -> if odd x then isqrt (xxx) else isqrt x) task :: Integer -> IO () task n = printf s n (length ns + 1) (i :: Int) (show...	Give a code snippet in #Haskell Background of the juggler sequence: Juggler sequences were publicized by an American mathematician and author Clifford A. Pickover. The name of the sequence gets it's name from the similarity of the rising and falling nature of the numbers in the sequences, much like balls in t...	christopher/rosetta-code
http://rosettacode.org/wiki/Palindrome_detection	Palindrome detection	A palindrome is a phrase which reads the same backward and forward. Task[edit] Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes) is a palindrome. For extra credit: Support Unicode characters. Write a second function (possibly as a wrapper to the first) which ...	#FBSL	FBSL	#APPTYPE CONSOLE FUNCTION stripNonAlpha(BYVAL s AS STRING) AS STRING DIM sTemp AS STRING = "" DIM c AS STRING FOR DIM i = 1 TO LEN(s) c = MID(s, i, 1) IF INSTR("ABCDEFGHIJKLMNOPQRSTUVWXYZ", c, 0, 1) THEN sTemp = stemp & c END IF NEXT RETURN sTemp END FUNCTION FUNCTION IsPalindrome(BYVAL s AS STRING) A...	Give a code snippet in #FBSL A palindrome is a phrase which reads the same backward and forward. Task[edit] Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes) is a palindrome. For extra credit: Support Unicode characters. Write a second function (possibly as ...	christopher/rosetta-code
http://rosettacode.org/wiki/Horizontal_sundial_calculations	Horizontal sundial calculations	Task Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location. For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit...	#Tcl	Tcl	set PI 3.1415927 fconfigure stdout -buffering none puts -nonewline "Enter latitude => "; gets stdin lat puts -nonewline "Enter longitude => "; gets stdin lng puts -nonewline "Enter legal meridian => "; gets stdin ref puts "" set slat [expr {sin($lat*$PI/180)}] puts [format " sine of latitude: %8g" $sl...	Give a code snippet in #Tcl Task Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location. For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, ...	christopher/rosetta-code
http://rosettacode.org/wiki/Read_a_file_character_by_character/UTF8	Read a file character by character/UTF8	Task Read a file one character at a time, as opposed to reading the entire file at once. The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached). The procedure should support the reading of files contain...	#Run_BASIC	Run BASIC	open file.txt" for binary as #f numChars = 1 ' specify number of characters to read a$ = input$(#f,numChars) ' read number of characters specified b$ = input$(#f,1) ' read one character close #f	Give a code snippet in #Run_BASIC Task Read a file one character at a time, as opposed to reading the entire file at once. The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached). The procedure should s...	christopher/rosetta-code
http://rosettacode.org/wiki/100_doors	100 doors	There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it). The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it. The third...	#Ada	Ada	with Ada.Text_Io; use Ada.Text_Io; procedure Doors is type Door_State is (Closed, Open); type Door_List is array(Positive range 1..100) of Door_State; The_Doors : Door_List := (others => Closed); begin for I in 1..100 loop for J in The_Doors'range loop if J mod I = 0 then ...	Give a code snippet in #Ada There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it). The second time, only visit every 2nd door (door #2, #4, #6, ...)...	christopher/rosetta-code
http://rosettacode.org/wiki/Ethiopian_multiplication	Ethiopian multiplication	Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving. Method: Take two numbers to be multiplied and write them down at the top of two columns. In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ...	#VBScript	VBScript	option explicit class List private theList private nOccupiable private nTop sub class_initialize nTop = 0 nOccupiable = 100 redim theList( nOccupiable ) end sub public sub store( x ) if nTop >= nOccupiable then nOccupiable = nOccupiable + 100 redim preserve theList( nOccupiable ) end if th...	Give a code snippet in #VBScript Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving. Method: Take two numbers to be multiplied and write them down at the top of two columns. In the left-hand column repeatedly halve the last number, discarding any remainders, an...	christopher/rosetta-code
http://rosettacode.org/wiki/Kronecker_product_based_fractals	Kronecker product based fractals	This task is based on Kronecker product of two matrices. If your language has no a built-in function for such product then you need to implement it first. The essence of fractals is self-replication (at least, self-similar replications). So, using n times self-product of the matrix (filled with 0/1) we ...	#Action.21	Action!	SET EndProg=*	Give a code snippet in #Action.21 This task is based on Kronecker product of two matrices. If your language has no a built-in function for such product then you need to implement it first. The essence of fractals is self-replication (at least, self-similar replications). So, using n times self-product of t...	christopher/rosetta-code
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), b...	#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....	Give a code snippet in #Java 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 sc...	christopher/rosetta-code
http://rosettacode.org/wiki/Towers_of_Hanoi	Towers of Hanoi	Task Solve the Towers of Hanoi problem with recursion.	#Delphi	Delphi	proc move(byte n, src, via, dest) void: if n>0 then move(n-1, src, dest, via); writeln("Move disk from pole ",src," to pole ",dest); move(n-1, via, src, dest) fi corp proc nonrec main() void: move(4, 1, 2, 3) corp	Give a code snippet in #Delphi Task Solve the Towers of Hanoi problem with recursion.	christopher/rosetta-code
http://rosettacode.org/wiki/Summarize_and_say_sequence	Summarize and say sequence	There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits: 0, 10, 1110, 3110, 132110, 1113122110, 311311222110 ... The terms generat...	#Racket	Racket	#lang racket (define (next s) (define v (make-vector 10 0)) (for ([c s]) (define d (- (char->integer #\9) (char->integer c))) (vector-set! v d (add1 (vector-ref v d)))) (string-append* (for/list ([x v] [i (in-range 9 -1 -1)] #:when (> x 0)) (format "~a~a" x i)))) (define (seq-of ...	Give a code snippet in #Racket There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits: 0, 10, 1110, 3110, 132110, 1113122110, 311...	christopher/rosetta-code
http://rosettacode.org/wiki/Here_document	Here document	A here document (or "heredoc") is a way of specifying a text block, preserving the line breaks, indentation and other whitespace within the text. Depending on the language being used, a here document is constructed using a command followed by "<<" (or some other symbol) followed by a token string. The text ...	#FreeBASIC	FreeBASIC	Dim As String text1 = " " & Chr(10) & _ "<<'FOO' " & Chr(10) & _ " 'jaja', `esto`" & Chr(10) & _ " <simula>" & Chr(10) & _ " \un\" & Chr(10) & _ !" ${ejemplo} de \"heredoc\"" & Chr(10) & _ " en FreeBASIC." Dim As String text2 = "Esta es la primera linea." & Chr(10) & _ "Esta es la segunda linea." & Chr(10) & _...	Give a code snippet in #FreeBASIC A here document (or "heredoc") is a way of specifying a text block, preserving the line breaks, indentation and other whitespace within the text. Depending on the language being used, a here document is constructed using a command followed by "<<" (or some other symbol) fol...	christopher/rosetta-code
http://rosettacode.org/wiki/Barnsley_fern	Barnsley fern	A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS). Task Create this fractal fern, using the following transformations: ƒ1 (chosen 1% of the time) xn + 1 = 0 yn + 1 = 0.16 yn ƒ2 (chosen 85% of the time) ...	#Ring	Ring	Load "guilib.ring" /* +--------------------------------------------------------------------------- + Program Name : Draw Barnsley Fern + Purpose : Draw Fern using Quadratic Equation and Random Number +--------------------------------------------------------------------------- */ ###------...	Give a code snippet in #Ring A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS). Task Create this fractal fern, using the following transformations: ƒ1 (chosen 1% of the time) xn + 1 = 0 yn + 1 = 0.16 yn ...	christopher/rosetta-code
http://rosettacode.org/wiki/Strip_comments_from_a_string	Strip comments from a string	Strip comments from a string You are encouraged to solve this task according to the task description, using any language you may know. The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line. Whitespace debacle: There is s...	#JavaScript	JavaScript	function stripComments(s) { var re1 = /^\s+\|\s+$/g; // Strip leading and trailing spaces var re2 = /\s*[#;].+$/g; // Strip everything after # or ; to the end of the line, including preceding spaces return s.replace(re1,'').replace(re2,''); } var s1 = 'apples, pears # and bananas'; var s2 = 'apples, pears ; a...	Give a code snippet in #JavaScript Strip comments from a string You are encouraged to solve this task according to the task description, using any language you may know. The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line...	christopher/rosetta-code
http://rosettacode.org/wiki/Additive_primes	Additive primes	Definitions In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes. Task Write a program to determine (and show here) all additive primes less than 500. Optionally, show the number of additive primes. Also see the OEIS entry: A046704 additive primes. ...	#BASIC	BASIC	10 DEFINT A-Z: E=500 20 DIM P(E): P(0)=-1: P(1)=-1 30 FOR I=2 TO SQR(E) 40 IF NOT P(I) THEN FOR J=I*2 TO E STEP I: P(J)=-1: NEXT 50 NEXT 60 FOR I=B TO E: IF P(I) GOTO 100 70 J=I: S=0 80 IF J>0 THEN S=S+J MOD 10: J=J\10: GOTO 80 90 IF NOT P(S) THEN N=N+1: PRINT I, 100 NEXT 110 PRINT: PRINT N;" additive primes found belo...	Give a code snippet in #BASIC Definitions In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes. Task Write a program to determine (and show here) all additive primes less than 500. Optionally, show the number of additive primes. Also see the OEIS entry:...	christopher/rosetta-code
http://rosettacode.org/wiki/Department_numbers	Department numbers	There is a highly organized city that has decided to assign a number to each of their departments: police department sanitation department fire department Each department can have a number between 1 and 7 (inclusive). The three department numbers are to be unique (different from each other) and mu...	#Clojure	Clojure	(let [n (range 1 8)] (for [police n sanitation n fire n :when (distinct? police sanitation fire) :when (even? police) :when (= 12 (+ police sanitation fire))] (println police sanitation fire)))	Give a code snippet in #Clojure There is a highly organized city that has decided to assign a number to each of their departments: police department sanitation department fire department Each department can have a number between 1 and 7 (inclusive). The three department numbers are to be unique (...	christopher/rosetta-code
http://rosettacode.org/wiki/Compiler/AST_interpreter	Compiler/AST interpreter	An AST interpreter interprets an Abstract Syntax Tree (AST) produced by a Syntax Analyzer. Task[edit] Take the AST output from the Syntax analyzer task, and interpret it as appropriate. Refer to the Syntax analyzer task for details of the AST. Loading the AST from the syntax analyzer is as simple as (pseudo code) de...	#Perl	Perl	#!/usr/bin/perl use strict; # interpreter.pl - execute a flatAST use warnings; # http://www.rosettacode.org/wiki/Compiler/AST_interpreter use integer; my %variables; tree()->run; sub tree { my $line = <> // die "incomplete tree\n"; (local $_, my $arg) = $line =~ /^(\w+\|;)\s+(.*)/ or die "bad input $line...	Give a code snippet in #Perl An AST interpreter interprets an Abstract Syntax Tree (AST) produced by a Syntax Analyzer. Task[edit] Take the AST output from the Syntax analyzer task, and interpret it as appropriate. Refer to the Syntax analyzer task for details of the AST. Loading the AST from the syntax analyzer is ...	christopher/rosetta-code
http://rosettacode.org/wiki/Fibonacci_sequence	Fibonacci sequence	The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...	#LOLCODE	LOLCODE	HAI 1.2 HOW DUZ I fibonacci YR N EITHER OF BOTH SAEM N AN 1 AN BOTH SAEM N AN 0 O RLY? YA RLY, FOUND YR 1 NO WAI I HAS A N1 I HAS A N2 N1 R DIFF OF N AN 1 N2 R DIFF OF N AN 2 N1 R fibonacci N1 N2 R fibonacci N2 FOUND YR SUM OF N1 AN N2 OIC IF U SAY SO KTHXBYE	Give a code snippet in #LOLCODE The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solutions a...	christopher/rosetta-code
http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously	Loop over multiple arrays simultaneously	Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: ...	#ALGOL_W	ALGOL W	begin % declare the three arrays % string(1) array a, b ( 1 :: 3 ); integer array c ( 1 :: 3 ); % initialise the arrays - have to do this element by element in Algol W % a(1) := "a"; a(2) := "b"; a(3) := "c"; b(1) := "A"; b(2) := "B"; b(3) := "...	Give a code snippet in #ALGOL_W Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this ex...	christopher/rosetta-code
http://rosettacode.org/wiki/Hello_world/Newline_omission	Hello world/Newline omission	Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output. Task Display the string Goodbye, World! without a trailing newline. Related tasks Hello world/Graphical Hello world/Line Printer Hello world/Standard error Hello world/Text	#Neko	Neko	/** hellonnl.neko Tectonics: nekoc hellonnl.neko neko hellonnl -or- nekoc hellonnl.neko nekotools boot hellonnl.n ./hellonnl */ $print("Goodbye, World!");	Give a code snippet in #Neko Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output. Task Display the string Goodbye, World! without a trailing newline. Related tasks Hello world/Graphical Hello world/Line Printer Hello world/Standa...	christopher/rosetta-code
http://rosettacode.org/wiki/Forest_fire	Forest fire	This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and Schwabl definition of the fores...	#Ruby	Ruby	class Forest_Fire Neighborhood = [-1,0,1].product([-1,0,1]) - [0,0] States = {empty:" ", tree:"T", fire:"#"} def initialize(xsize, ysize=xsize, p=0.5, f=0.01) @xsize, @ysize, @p, @f = xsize, ysize, p, f @field = Array.new(xsize+1) {\|i\| Array.new(ysize+1, :empty)} @generation = 0 end def evolve...	Give a code snippet in #Ruby This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and S...	christopher/rosetta-code
http://rosettacode.org/wiki/Ordered_words	Ordered words	An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally assume that you have download...	#XPL0	XPL0	string 0; \use zero-terminated strings int MaxLen, Pass, I, Ch, Ch0; char Word(25); def LF=$0A, CR=$0D, EOF=$1A; [FSet(FOpen("unixdict.txt", 0), ^I); MaxLen:= 0; for Pass:= 1 to 2 do [OpenI(3); repeat I:= 0; Ch0:= 0; loop [repeat Ch:= ChIn(3) until Ch # CR; ...	Give a code snippet in #XPL0 An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally...	christopher/rosetta-code
http://rosettacode.org/wiki/Multifactorial	Multifactorial	The factorial of a number, written as n ! {\displaystyle n!} , is defined as n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displaystyle n!=n(n-1)(n-2)...(2)(1)} . Multifactorials generalize factorials as follows: n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displaystyle n!=n(n-1)(n-2)...(2)(...	#GAP	GAP	MultiFactorial := function(n, k) local r; r := 1; while n > 1 do r := r*n; n := n - k; od; return r; end; PrintArray(List([1 .. 10], n -> List([1 .. 5], k -> MultiFactorial(n, k)))); [ [ 1, 1, 1, 1, 1 ], [ 2, 2, 2, 2,...	Give a code snippet in #GAP The factorial of a number, written as n ! {\displaystyle n!} , is defined as n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displaystyle n!=n(n-1)(n-2)...(2)(1)} . Multifactorials generalize factorials as follows: n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displ...	christopher/rosetta-code
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers	Luhn test of credit card numbers	The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order of the digits in the number. Tak...	#Swift	Swift	func luhn(_ number: String) -> Bool { return number.reversed().enumerated().map({ let digit = Int(String($0.element))! let even = $0.offset % 2 == 0 return even ? digit : digit == 9 ? 9 : digit * 2 % 9 }).reduce(0, +) % 10 == 0 } luhn("49927398716") // true luhn("49927398717") // false	Give a code snippet in #Swift The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order of...	christopher/rosetta-code
http://rosettacode.org/wiki/Base64_decode_data	Base64 decode data	See Base64 encode data. Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file. When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output with incorrect padding. Obviously...	#zkl	zkl	var [const] MsgHash=Import("zklMsgHash"), Curl=Import("zklCurl"); icon:=Curl().get("http://rosettacode.org/favicon.ico"); //-->(Data(4,331),693,0) icon=icon[0][icon[1],*]; // remove header iconEncoded:=MsgHash.base64encode(icon); iconDecoded:=MsgHash.base64decode(iconEncoded); File("rosettaCodeIcon.ico","wb").write(i...	Give a code snippet in #zkl See Base64 encode data. Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file. When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output with...	christopher/rosetta-code
http://rosettacode.org/wiki/Send_an_unknown_method_call	Send an unknown method call	Task Invoke an object method where the name of the method to be invoked can be generated at run time. Related tasks Respond to an unknown method call. Runtime evaluation	#Logtalk	Logtalk	:- object(foo). :- public(bar/1). bar(42). :- end_object.	Give a code snippet in #Logtalk Task Invoke an object method where the name of the method to be invoked can be generated at run time. Related tasks Respond to an unknown method call. Runtime evaluation	christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort	Sorting algorithms/Selection sort	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#Io	Io	List do ( selectionSortInPlace := method( size repeat(idx, swapIndices(idx, indexOf(slice(idx, size) min)) ) ) ) l := list(-1, 4, 2, -9) l selectionSortInPlace println # ==> list(-9, -1, 2, 4)	Give a code snippet in #Io Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort ...	christopher/rosetta-code
http://rosettacode.org/wiki/Spiral_matrix	Spiral matrix	Task Produce a spiral array. A spiral array is a square arrangement of the first N2 natural numbers, where the numbers increase sequentially as you go around the edges of the array spiraling inwards. For example, given 5, produce this array: 0 1 2 3 4 15 16 17 18 5 14 23 24 19 6 13 22 21 ...	#IS-BASIC	IS-BASIC	100 PROGRAM "SpiralMa.bas" 110 TEXT 80 120 INPUT PROMPT "Enter size of matrix (max. 10): ":N 130 NUMERIC A(1 TO N,1 TO N) 140 CALL INIT(A) 150 CALL WRITE(A) 160 DEF INIT(REF T) 170 LET BCOL,BROW,COL,ROW=1:LET TCOL,TROW=N:LET DIR=0 180 FOR I=0 TO N^2-1 190 LET T(COL,ROW)=I 200 SELECT CASE DIR 210 CASE 0 ...	Give a code snippet in #IS-BASIC Task Produce a spiral array. A spiral array is a square arrangement of the first N2 natural numbers, where the numbers increase sequentially as you go around the edges of the array spiraling inwards. For example, given 5, produce this array: 0 1 2 3 4 15 16...	christopher/rosetta-code
http://rosettacode.org/wiki/Loops/For_with_a_specified_step	Loops/For with a specified step	Task Demonstrate a for-loop where the step-value is greater than one. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within loop b...	#Never	Never	for (i = 0; i < 10; i += 3)	Give a code snippet in #Never Task Demonstrate a for-loop where the step-value is greater than one. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Inc...	christopher/rosetta-code
http://rosettacode.org/wiki/M%C3%B6bius_function	Möbius function	The classical Möbius function: μ(n) is an important multiplicative function in number theory and combinatorics. There are several ways to implement a Möbius function. A fairly straightforward method is to find the prime factors of a positive integer n, then define μ(n) based on the sum of the primitive factors. It ha...	#GW-BASIC	GW-BASIC	10 FOR T = 0 TO 9 20 FOR U = 1 TO 10 30 N = 10T + U 40 GOSUB 100 50 PRINT USING "## ";M; 60 NEXT U 70 PRINT 80 NEXT T 90 END 100 IF N = 1 THEN M = 1 : RETURN 110 M = 1 : F = 2 120 IF N MOD (FF) = 0 THEN M = 0 : RETURN 130 IF N MOD F = 0 THEN GOSUB 170 140 F = F + 1 150 IF F <= N THEN GOTO 120 160 RETURN 170 M = -M 1...	Give a code snippet in #GW-BASIC The classical Möbius function: μ(n) is an important multiplicative function in number theory and combinatorics. There are several ways to implement a Möbius function. A fairly straightforward method is to find the prime factors of a positive integer n, then define μ(n) based on the s...	christopher/rosetta-code
http://rosettacode.org/wiki/Hello_world/Newbie	Hello world/Newbie	Task Guide a new user of a language through the steps necessary to install the programming language and selection of a text editor if needed, to run the languages' example in the Hello world/Text task. Assume the language-newbie is a programmer in another language. Assume the language-newbie is competent in install...	#BQN	BQN	rlwrap ./BQN	Give a code snippet in #BQN Task Guide a new user of a language through the steps necessary to install the programming language and selection of a text editor if needed, to run the languages' example in the Hello world/Text task. Assume the language-newbie is a programmer in another language. Assume the language-n...	christopher/rosetta-code
http://rosettacode.org/wiki/Truncatable_primes	Truncatable primes	A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 7...	#PowerShell	PowerShell	function IsPrime ( [int] $num ) { $isprime = @{} 2..[math]::sqrt($num) \| Where-Object { $isprime[$_] -eq $null } \| ForEach-Object { $_ $isprime[$_] = $true for ( $i=$_*$_ ; $i -le $num; $i += $_ ) { $isprime[$i] = $false } } 2..$num \| Where-Object { $isprime[$_] -...	Give a code snippet in #PowerShell A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-trun...	christopher/rosetta-code
http://rosettacode.org/wiki/Null_object	Null object	Null (or nil) is the computer science concept of an undefined or unbound object. Some languages have an explicit way to access the null object, and some don't. Some languages distinguish the null object from undefined values, and some don't. Task Show how to access null in your language by checking to see if an ob...	#langur	langur	val .x, .y = true, null writeln .x == null writeln .y == null writeln .x ==? null writeln .y ==? null # null not a "truthy" result writeln if(null: 0; 1)	Give a code snippet in #langur Null (or nil) is the computer science concept of an undefined or unbound object. Some languages have an explicit way to access the null object, and some don't. Some languages distinguish the null object from undefined values, and some don't. Task Show how to access null in your lang...	christopher/rosetta-code
http://rosettacode.org/wiki/Longest_common_substring	Longest common substring	Task Write a function that returns the longest common substring of two strings. Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing". Note that substrings are consecutive characters within a string....	#VBScript	VBScript	Function lcs(string1,string2) For i = 1 To Len(string1) tlcs = tlcs & Mid(string1,i,1) If InStr(string2,tlcs) Then If Len(tlcs) > Len(lcs) Then lcs = tlcs End If Else tlcs = "" End If Next End Function WScript.Echo lcs(WScript.Arguments(0),WScript.Arguments(1))	Give a code snippet in #VBScript Task Write a function that returns the longest common substring of two strings. Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing". Note that substrings are conse...	christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Bogosort	Sorting algorithms/Bogosort	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#PHP	PHP	function bogosort($l) { while (!in_order($l)) shuffle($l); return $l; } function in_order($l) { for ($i = 1; $i < count($l); $i++) if ($l[$i] < $l[$i-1]) return FALSE; return TRUE; }	Give a code snippet in #PHP Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort...	christopher/rosetta-code
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation	Horner's rule for polynomial evaluation	A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...	#FunL	FunL	import lists.foldr def horner( poly, x ) = foldr( \a, b -> a + b*x, 0, poly ) println( horner([-19, 7, -4, 6], 3) )	Give a code snippet in #FunL A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\d...	christopher/rosetta-code
http://rosettacode.org/wiki/Sort_an_array_of_composite_structures	Sort an array of composite structures	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#Rust	Rust	use std::cmp::Ordering; #[derive(Debug)] struct Employee { name: String, category: String, } impl Employee { fn new(name: &str, category: &str) -> Self { Employee { name: name.into(), category: category.into(), } } } impl PartialEq for Employee { fn eq(&...	Give a code snippet in #Rust Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sor...	christopher/rosetta-code
http://rosettacode.org/wiki/Population_count	Population count	Population count You are encouraged to solve this task according to the task description, using any language you may know. The population count is the number of 1s (ones) in the binary representation of a non-negative integer. Population count is also known as: pop count popcount sideways sum ...	#8086_Assembly	8086 Assembly	cpu 8086 bits 16 org 100h section .text ;;; Calculate hamming weights of 3^0 to 3^29. ;;; 3^29 needs a 48-bit representation, which ;;; we'll put in BP:SI:DI. xor bp,bp ; BP:SI:DI = 1 xor si,si xor di,di inc di mov cx,30 ;;; Calculate pop count of BP:SI:DI pow3s: push bp ; Keep state push si push di xo...	Give a code snippet in #8086_Assembly Population count You are encouraged to solve this task according to the task description, using any language you may know. The population count is the number of 1s (ones) in the binary representation of a non-negative integer. Population count is also known as: p...	christopher/rosetta-code
http://rosettacode.org/wiki/Ray-casting_algorithm	Ray-casting algorithm	This page uses content from Wikipedia. The original article was at Point_in_polygon. 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) Given a point and a polygon, check if the point is inside or out...	#REXX	REXX	/REXX program verifies if a horizontal ray from point P intersects a polygon. / call points 5 5, 5 8, -10 5, 0 5, 10 5, 8 5, 10 10 A= 2.5; B= 7.5 /* ◄───── used for shorter arguments (below).*/ call poly 0 0, 10 0, 10 10, 0 10 ...	Give a code snippet in #REXX This page uses content from Wikipedia. The original article was at Point_in_polygon. 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) Given a point and a polygon, check...	christopher/rosetta-code
http://rosettacode.org/wiki/List_comprehensions	List comprehensions	A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name. Some attributes of a list comprehension are: They should be distinct from (nested) for loops and the use of map and filter functio...	#JavaScript	JavaScript	// USING A LIST MONAD DIRECTLY, WITHOUT SPECIAL SYNTAX FOR LIST COMPREHENSIONS (function (n) { return mb(r(1, n), function (x) { // x <- [1..n] return mb(r(1 + x, n), function (y) { // y <- [1+x..n] return mb(r(1 + y, n), function (z) { // z <- [1+y..n] return x * x + y * y === z * z ? [...	Give a code snippet in #JavaScript A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name. Some attributes of a list comprehension are: They should be distinct from (nested) for loops a...	christopher/rosetta-code
http://rosettacode.org/wiki/Mertens_function	Mertens function	The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number. It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möbius numbers from n == 1 through n...	#Nim	Nim	import sequtils, strformat func mertensNumbers(max: int): seq[int] = result = repeat(1, max + 1) for n in 2..max: for k in 2..n: dec result[n], result[n div k] const Max = 1000 let mertens = mertensNumbers(Max) echo "First 199 Mertens numbers:" const Count = 200 var column = 0 for i in 0..<Count: ...	Give a code snippet in #Nim The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number. It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möbius ...	christopher/rosetta-code
http://rosettacode.org/wiki/Multi-dimensional_array	Multi-dimensional array	For the purposes of this task, the actual memory layout or access method of this data structure is not mandated. It is enough to: State the number and extent of each index to the array. Provide specific, ordered, integer indices for all dimensions of the array together with a new value to update the indexed value. ...	#Racket	Racket	# Raku supports multi dimension arrays natively. There are no arbitrary limits on the number of dimensions or maximum indices. Theoretically, you could have an infinite number of dimensions of infinite length, though in practice more than a few dozen dimensions gets unwieldy. An infinite maximum index is a fairly commo...	Give a code snippet in #Racket For the purposes of this task, the actual memory layout or access method of this data structure is not mandated. It is enough to: State the number and extent of each index to the array. Provide specific, ordered, integer indices for all dimensions of the array together with a new val...	christopher/rosetta-code
http://rosettacode.org/wiki/Empty_program	Empty program	Task Create the simplest possible program that is still considered "correct."	#DCL	DCL	{}	Give a code snippet in #DCL Task Create the simplest possible program that is still considered "correct."	christopher/rosetta-code
http://rosettacode.org/wiki/Loops/Infinite	Loops/Infinite	Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within l...	#ReScript	ReScript	while true { Js.log("SPAM") }	Give a code snippet in #ReScript Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach L...	christopher/rosetta-code
http://rosettacode.org/wiki/A%2BB	A+B	A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used. Task Given two integers, A and B. Their sum needs to be calculated. Input data Two integers are written in the input stream, separated by space(s): ( − 1000 ≤...	#SPAD	SPAD	(1) -> integer READ()$Lisp + integer READ()$Lisp 333 444 (1) 777 Type: PositiveInteger	Give a code snippet in #SPAD A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used. Task Given two integers, A and B. Their sum needs to be calculated. Input data Two integers are written in the input stream, separated...	christopher/rosetta-code
http://rosettacode.org/wiki/Pseudo-random_numbers/Combined_recursive_generator_MRG32k3a	Pseudo-random numbers/Combined recursive generator MRG32k3a	MRG32k3a Combined recursive generator (pseudo-code) /* Constants / / First generator / a1 = [0, 1403580, -810728] m1 = 232 - 209 / Second Generator / a2 = [527612, 0, -1370589] m2 = 232 - 22853 d = m1 + 1 class MRG32k3a x1 = [0, 0, 0] / list of three last values of...	#C	C	#include <math.h> #include <stdio.h> #include <stdint.h> int64_t mod(int64_t x, int64_t y) { int64_t m = x % y; if (m < 0) { if (y < 0) { return m - y; } else { return m + y; } } return m; } // Constants // First generator const static int64_t a1[3] = ...	Give a code snippet in #C MRG32k3a Combined recursive generator (pseudo-code) /* Constants / / First generator / a1 = [0, 1403580, -810728] m1 = 232 - 209 / Second Generator / a2 = [527612, 0, -1370589] m2 = 232 - 22853 d = m1 + 1 class MRG32k3a x1 = [0, 0, 0] / l...	christopher/rosetta-code
http://rosettacode.org/wiki/Search_a_list	Search a list	Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...	#Ring	Ring	haystack = ["alpha","bravo","charlie","delta","echo","foxtrot","golf", "hotel","india","juliet","kilo","lima","mike","needle", "november","oscar","papa","quebec","romeo","sierra","tango", "needle","uniform","victor","whisky","x-ray","yankee","zulu"] needle = "needle" maxindex = len(haystack) for index = 1 to ...	Give a code snippet in #Ring Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle tha...	christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort	Sorting algorithms/Cocktail sort	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#PL.2FI	PL/I	cocktail: procedure (A); declare A() fixed; declare t fixed; declare stable bit (1); declare (i, n) fixed binary (31); n = hbound(A,1); do until (stable); stable = '1'b; do i = 1 to n-1, n-1 to 1 by -1; if A(i) > A(i+1) then do; stable = '0'b; / still unsorted, so ...	Give a code snippet in #PL.2FI Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick s...	christopher/rosetta-code
http://rosettacode.org/wiki/Loops/Downward_for	Loops/Downward for	Task Write a for loop which writes a countdown from 10 to 0. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within loop body...	#Euphoria	Euphoria	for i = 10 to 0 by -1 do ? i end for	Give a code snippet in #Euphoria Task Write a for loop which writes a countdown from 10 to 0. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Inc...	christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort	Sorting algorithms/Merge sort	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#CoffeeScript	CoffeeScript	# This is a simple version of mergesort that returns brand-new arrays. # A more sophisticated version would do more in-place optimizations. merge_sort = (arr) -> if arr.length <= 1 return (elem for elem in arr) m = Math.floor(arr.length / 2) arr1 = merge_sort(arr.slice 0, m) arr2 = merge_sort(arr.slice m) ...	Give a code snippet in #CoffeeScript Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Q...	christopher/rosetta-code
http://rosettacode.org/wiki/User_input/Text	User input/Text	User input/Text is part of Short Circuit's Console Program Basics selection. Task Input a string and the integer 75000 from the text console. See also: User input/Graphical	#D.C3.A9j.C3.A0_Vu	Déjà Vu	input s: !print\ s !decode!utf-8 !read-line!stdin local :astring input "Enter a string: " true while: try: to-num input "Enter the number 75000: " /= 75000 catch value-error: true	Give a code snippet in #D.C3.A9j.C3.A0_Vu User input/Text is part of Short Circuit's Console Program Basics selection. Task Input a string and the integer 75000 from the text console. See also: User input/Graphical	christopher/rosetta-code
http://rosettacode.org/wiki/Search_a_list	Search a list	Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...	#zkl	zkl	L("Krusty","Charlie","Bozo","Bozo").index("Charlie") //--> 1 L("Krusty","Charlie","Bozo","Bozo").index("fred") //--> throws index error	Give a code snippet in #zkl Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that...	christopher/rosetta-code
http://rosettacode.org/wiki/Loops/Foreach	Loops/Foreach	Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for...	#ALGOL_68	ALGOL 68	[]UNION(STRING, INT, PROC(REF FILE)VOID) collection = ("Mary","Had",1,"little","lamb.",new line); FOR index FROM LWB collection TO UPB collection DO print((collection[index]," ")) OD	Give a code snippet in #ALGOL_68 Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Lo...	christopher/rosetta-code
http://rosettacode.org/wiki/Ordered_words	Ordered words	An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally assume that you have download...	#Io	Io	file := File clone openForReading("./unixdict.txt") words := file readLines file close maxLen := 0 orderedWords := list() words foreach(word, if( (word size >= maxLen) and (word == (word asMutable sort)), if( word size > maxLen, maxLen = word size orderedWords empty ) ...	Give a code snippet in #Io An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally a...	christopher/rosetta-code
http://rosettacode.org/wiki/Thue-Morse	Thue-Morse	Task Create a Thue-Morse sequence. See also YouTube entry: The Fairest Sharing Sequence Ever YouTube entry: Math and OCD - My story with the Thue-Morse sequence Task: Fairshare between two and more	#Factor	Factor	USING: io kernel math math.parser sequences ; : thue-morse ( seq n -- seq' ) [ [ ] [ [ 1 bitxor ] map ] bi append ] times ; : print-tm ( seq -- ) [ number>string ] map "" join print ; 7 <iota> [ { 0 } swap thue-morse print-tm ] each	Give a code snippet in #Factor Task Create a Thue-Morse sequence. See also YouTube entry: The Fairest Sharing Sequence Ever YouTube entry: Math and OCD - My story with the Thue-Morse sequence Task: Fairshare between two and more	christopher/rosetta-code
http://rosettacode.org/wiki/Bulls_and_cows	Bulls and cows	Bulls and Cows Task Create a four digit random number from the digits 1 to 9, without duplication. The program should: ask for guesses to this number reject guesses that are malformed print the score for the guess The score is computed as: The player wins if the guess is the same as the random...	#Icon_and_Unicon	Icon and Unicon	procedure main() digits := "123456789" every !digits :=: ?digits num := digits[1+:4] repeat if score(num, getGuess(num)) then break write("Good job.") end procedure getGuess(num) repeat { writes("Enter a guess: ") guess := read() \| stop("Quitter!") if (guess * '123456...	Give a code snippet in #Icon_and_Unicon Bulls and Cows Task Create a four digit random number from the digits 1 to 9, without duplication. The program should: ask for guesses to this number reject guesses that are malformed print the score for the guess The score is computed as: The player wi...	christopher/rosetta-code
http://rosettacode.org/wiki/Singly-linked_list/Element_insertion	Singly-linked list/Element insertion	Singly-Linked List (element) singly-linked list Using this method, insert an element C into a list comprised of elements A->B, following element A. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Trav...	#Kotlin	Kotlin	// version 1.1.2 class Node<T: Number>(var data: T, var next: Node<T>? = null) { override fun toString(): String { val sb = StringBuilder(this.data.toString()) var node = this.next while (node != null) { sb.append(" -> ", node.data.toString()) node = node.next ...	Give a code snippet in #Kotlin Singly-Linked List (element) singly-linked list Using this method, insert an element C into a list comprised of elements A->B, following element A. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definiti...	christopher/rosetta-code
http://rosettacode.org/wiki/Date_format	Date format	This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the current date in the formats of: 2007-11-23 and Friday, November 23, 2007	#NewLISP	NewLISP	; file: date-format.lsp ; url: http://rosettacode.org/wiki/Date_format ; author: oofoe 2012-02-01 ; The "now" function returns the current time as a list. A time zone ; offset in minutes can be supplied. The example below is for Eastern ; Standard Time. NewLISP's implicit list indexing is used to extract ; the f...	Give a code snippet in #NewLISP This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the current date in the formats of: 2007-11-23 and Friday, November 23, 2007	christopher/rosetta-code
http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running	Determine if only one instance is running	This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.	#Oz	Oz	functor import Application Open System define fun {IsAlreadyRunning} try S = {New Open.socket init} in {S bind(takePort:12345)} false catch system(os(os "bind" ...) ...) then true end end if {IsAlreadyRunning} then {System.showInfo "Exiting because already running."} ...	Give a code snippet in #Oz This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.	christopher/rosetta-code
http://rosettacode.org/wiki/Dining_philosophers	Dining philosophers	The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra. Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou...	#PicoLisp	PicoLisp	(de dining (Name State) (loop (prinl Name ": " State) (state 'State # Dispatch according to state (thinking 'hungry) # If thinking, get hungry (hungry # If hungry, grab random fork (if (rand T) (and ...	Give a code snippet in #PicoLisp The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra. Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and e...	christopher/rosetta-code
http://rosettacode.org/wiki/Sort_an_integer_array	Sort an integer array	Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick sort O(n log2n) sorts Shell Sort ...	#ALGOL_68	ALGOL 68	CO PR READ "shell_sort.a68" PR CO MODE TYPE = INT; PROC in place shell sort = (REF[]TYPE seq)REF[]TYPE:( INT inc := ( UPB seq + LWB seq + 1 ) OVER 2; WHILE inc NE 0 DO FOR index FROM LWB seq TO UPB seq DO INT i := index; TYPE el = seq[i]; WHILE ( i - LWB seq >= inc...	Give a code snippet in #ALGOL_68 Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort \| Merge sort \| Patience sort \| Quick...	christopher/rosetta-code
http://rosettacode.org/wiki/Semiprime	Semiprime	Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes are also known as: semi-primes biprimes bi-primes 2-almost primes or simply: P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...	#Erlang	Erlang	-module(factors). -export([factors/1,kthfactor/2]). factors(N) -> factors(N,2,[]). factors(1,_,Acc) -> Acc; factors(N,K,Acc) when N rem K == 0 -> factors(N div K,K, [K\|Acc]); factors(N,K,Acc) -> factors(N,K+1,Acc). % is integer N factorable into M primes? kthfactor(N,M) -> case l...	Give a code snippet in #Erlang Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes are also known as: semi-primes biprimes bi-primes 2-almost primes or simply: P2 Example 1679 = 23 × 73 (This particular number was ch...	christopher/rosetta-code
http://rosettacode.org/wiki/Increment_a_numerical_string	Increment a numerical string	Task Increment a numerical string.	#ML	ML	ntos ` ston "1234" + 1;	Give a code snippet in #ML Task Increment a numerical string.	christopher/rosetta-code
http://rosettacode.org/wiki/Forest_fire	Forest fire	This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and Schwabl definition of the fores...	#Ada	Ada	with Ada.Numerics.Float_Random; use Ada.Numerics.Float_Random; with Ada.Text_IO; use Ada.Text_IO; procedure Forest_Fire is type Cell is (Empty, Tree, Fire); type Board is array (Positive range <>, Positive range <>) of Cell; procedure Step (S : in out Board; P, F : Float; Dice : Generator) is...	Give a code snippet in #Ada This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and Sc...	christopher/rosetta-code
http://rosettacode.org/wiki/Rosetta_Code/Rank_languages_by_popularity	Rosetta Code/Rank languages by popularity	Rosetta Code/Rank languages by popularity You are encouraged to solve this task according to the task description, using any language you may know. Task Sort the most popular computer programming languages based in number of members in Rosetta Code categories. Sample output on 01 juin 2022 at 14:13 +02 Rank: 1 (1,...	#Oz	Oz	declare [HTTPClient] = {Module.link ['x-ozlib://mesaros/net/HTTPClient.ozf']} [Regex] = {Module.link ['x-oz://contrib/regex']} fun {GetPage RawUrl} Client = {New HTTPClient.urlGET init(inPrms(toFile:false toStrm:true) _)} Url = {VirtualString.toString RawUrl} OutParams HttpResponseParams i...	Give a code snippet in #Oz Rosetta Code/Rank languages by popularity You are encouraged to solve this task according to the task description, using any language you may know. Task Sort the most popular computer programming languages based in number of members in Rosetta Code categories. Sample output on 01 juin 202...	christopher/rosetta-code
http://rosettacode.org/wiki/Almost_prime	Almost prime	A k-Almost-prime is a natural number n {\displaystyle n} that is the product of k {\displaystyle k} (possibly identical) primes. Example 1-almost-primes, where k = 1 {\displaystyle k=1} , are the prime numbers themselves. 2-almost-primes, where k = 2 {\displaystyl...	#Raku	Raku	sub is-k-almost-prime($n is copy, $k) returns Bool { loop (my ($p, $f) = 2, 0; $f < $k && $p$p <= $n; $p++) { $n /= $p, $f++ while $n %% $p; } $f + ($n > 1) == $k; } for 1 .. 5 -> $k { say ~.[^10] given grep { is-k-almost-prime($_, $k) }, 2 .. }	Give a code snippet in #Raku A k-Almost-prime is a natural number n {\displaystyle n} that is the product of k {\displaystyle k} (possibly identical) primes. Example 1-almost-primes, where k = 1 {\displaystyle k=1} , are the prime numbers themselves. 2-almost-primes, whe...	christopher/rosetta-code
http://rosettacode.org/wiki/Video_display_modes	Video display modes	The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.	#BBC_BASIC	BBC BASIC	10 MODE 1: REM 320x256 4 colour graphics	Give a code snippet in #BBC_BASIC The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.	christopher/rosetta-code
http://rosettacode.org/wiki/Sequence:_smallest_number_greater_than_previous_term_with_exactly_n_divisors	Sequence: smallest number greater than previous term with exactly n divisors	Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors. Task Show here, on this page, at least the first 15 terms of the sequence. See also OEIS:A069654 Related tasks Sequence: smallest number with exactly n divisors Sequence: nth ...	#Factor	Factor	USING: io kernel math math.primes.factors prettyprint sequences ; : next ( n num -- n' num' ) [ 2dup divisors length = ] [ 1 + ] do until [ 1 + ] dip ; : A069654 ( n -- seq ) [ 2 1 ] dip [ [ next ] keep ] replicate 2nip ; "The first 15 terms of the sequence are:" print 15 A069654 .	Give a code snippet in #Factor Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors. Task Show here, on this page, at least the first 15 terms of the sequence. See also OEIS:A069654 Related tasks Sequence: smallest number with ex...	christopher/rosetta-code
http://rosettacode.org/wiki/Anti-primes	Anti-primes	The anti-primes (or highly composite numbers, sequence A002182 in the OEIS) are the natural numbers with more factors than any smaller than itself. Task Generate and show here, the first twenty anti-primes. Related tasks Factors of an integer Sieve of Eratosthenes	#Fortran	Fortran	program anti_primes use iso_fortran_env, only: output_unit implicit none integer :: n, d, maxDiv, pCount write(output_unit,*) "The first 20 anti-primes are:" n = 1 maxDiv = 0 pCount = 0 do if (pCount >= 20) exit d = countDivisors(n) if (d > maxDiv) then ...	Give a code snippet in #Fortran The anti-primes (or highly composite numbers, sequence A002182 in the OEIS) are the natural numbers with more factors than any smaller than itself. Task Generate and show here, the first twenty anti-primes. Related tasks Factors of an integer Sieve of Eratosthenes	christopher/rosetta-code
http://rosettacode.org/wiki/Magic_squares_of_singly_even_order	Magic squares of singly even order	A magic square is an NxN square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant). A magic square of singly even order has a size that is a multiple of 4, plus 2 (e.g. 6,...	#zkl	zkl	class MagicSquareSinglyEven{ fcn init(n){ var result=magicSquareSinglyEven(n) } fcn toString{ sink,n:=Sink(String),result.len(); // num collumns fmt:="%2s "; foreach row in (result) { sink.write(row.apply('wrap(n){ fmt.fmt(n) }).concat(),"\n") } sink.write("\nMagic constant: %d"....	Give a code snippet in #zkl A magic square is an NxN square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant). A magic square of singly even order has a size that is a m...	christopher/rosetta-code
http://rosettacode.org/wiki/Write_entire_file	Write entire file	Task (Over)write a file so that it contains a string. The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.	#Julia	Julia	function writeFile(filename, data) f = open(filename, "w") write(f, data) close(f) end writeFile("test.txt", "Hi there.")	Give a code snippet in #Julia Task (Over)write a file so that it contains a string. The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.	christopher/rosetta-code
http://rosettacode.org/wiki/Pointers_and_references	Pointers and references	Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic \| Comparison Boolean Operations Bitwise \| Logical String Operations Concatenation \| Interpolation \|...	#ARM_Assembly	ARM Assembly	;this example uses VASM syntax, your assembler may not use the # before constants or the semicolon for comments MOV R1,#0x04000000 MOV R0,#0x403 STR R0,[R1] ;store 0x403 into memory address 0x04000000.	Give a code snippet in #ARM_Assembly Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic \| Comparison Boolean Operations Bitwise \| Logical String Oper...	christopher/rosetta-code
http://rosettacode.org/wiki/Detect_division_by_zero	Detect division by zero	Task Write a function to detect a divide by zero error without checking if the denominator is zero.	#RPGIV	RPGIV	dcl-c DIVIDE_BY_ZERO 00102; dcl-s result zoned(5:2); dcl-s value1 zoned(5:2); dcl-s value2 zoned(5:2); value1 = 10; value2 = 0; monitor; eval(h) result = value1 / value2; // Using half rounding here for the eval result on-error DIVIDE_BY_ZERO; ...	Give a code snippet in #RPGIV Task Write a function to detect a divide by zero error without checking if the denominator is zero.	christopher/rosetta-code
http://rosettacode.org/wiki/The_ISAAC_Cipher	The ISAAC Cipher	ISAAC is a cryptographically secure pseudo-random number generator (CSPRNG) and stream cipher. It was developed by Bob Jenkins from 1993 (http://burtleburtle.net/bob/rand/isaac.html) and placed in the Public Domain. ISAAC is fast - especially when optimised - and portable to most architectures in nearly all programming...	#Tcl	Tcl	package require Tcl 8.6 oo::class create ISAAC { variable aa bb cc mm randrsl randcnt constructor {seed} { namespace eval tcl { namespace eval mathfunc { proc mm {idx} { upvar 1 mm list lindex $list [expr {$idx % [llength $list]}] } proc clamp {value} { expr {$value & 0xFFFFFFF...	Give a code snippet in #Tcl ISAAC is a cryptographically secure pseudo-random number generator (CSPRNG) and stream cipher. It was developed by Bob Jenkins from 1993 (http://burtleburtle.net/bob/rand/isaac.html) and placed in the Public Domain. ISAAC is fast - especially when optimised - and portable to most architectu...	christopher/rosetta-code
http://rosettacode.org/wiki/Fibonacci_sequence	Fibonacci sequence	The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...	#Corescript	Corescript	print Fibonacci Sequence: var previous = 1 var number = 0 var temp = (blank) :fib if number > 50000000000:kill print (number) set temp = (add number previous) set previous = (number) set number = (temp) goto fib :kill stop	Give a code snippet in #Corescript The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solution...	christopher/rosetta-code
http://rosettacode.org/wiki/Longest_increasing_subsequence	Longest increasing subsequence	Calculate and show here a longest increasing subsequence of the list: { 3 , 2 , 6 , 4 , 5 , 1 } {\displaystyle \{3,2,6,4,5,1\}} And of the list: { 0 , 8 , 4 , 12 , 2 , 10 , 6 , 14 , 1 , 9 , 5 , 13 , 3 , 11 , 7 , 15 } {\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}} Note that a list may have m...	#Ruby	Ruby	Node = Struct.new(:val, :back) def lis(n) pileTops = [] # sort into piles for x in n # binary search low, high = 0, pileTops.size-1 while low <= high mid = low + (high - low) / 2 if pileTops[mid].val >= x high = mid - 1 else low = mid + 1 end end i = l...	Give a code snippet in #Ruby Calculate and show here a longest increasing subsequence of the list: { 3 , 2 , 6 , 4 , 5 , 1 } {\displaystyle \{3,2,6,4,5,1\}} And of the list: { 0 , 8 , 4 , 12 , 2 , 10 , 6 , 14 , 1 , 9 , 5 , 13 , 3 , 11 , 7 , 15 } {\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}}...	christopher/rosetta-code
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive	Verify distribution uniformity/Naive	This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...	#JavaScript	JavaScript	function distcheck(random_func, times, opts) { if (opts === undefined) opts = {} opts['delta'] = opts['delta'] \|\| 2; var count = {}, vals = []; for (var i = 0; i < times; i++) { var val = random_func(); if (! has_property(count, val)) { count[val] = 1; vals.push...	Give a code snippet in #JavaScript This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing ra...	christopher/rosetta-code
http://rosettacode.org/wiki/Bitmap/Read_an_image_through_a_pipe	Bitmap/Read an image through a pipe	This task is the opposite of the PPM conversion through a pipe. In this task, using a delegate tool (like cjpeg, one of the netpbm package, or convert of the ImageMagick package) we read an image file and load it into the data storage type defined here. We can also use the code from Read ppm file, so that we can use PP...	#OCaml	OCaml	let read_image ~filename = if not(Sys.file_exists filename) then failwith(Printf.sprintf "the file %s does not exist" filename); let cmd = Printf.sprintf "convert \"%s\" ppm:-" filename in let ic, oc = Unix.open_process cmd in let img = read_ppm ~ic in (img) ;;	Give a code snippet in #OCaml This task is the opposite of the PPM conversion through a pipe. In this task, using a delegate tool (like cjpeg, one of the netpbm package, or convert of the ImageMagick package) we read an image file and load it into the data storage type defined here. We can also use the code from Read ...	christopher/rosetta-code
http://rosettacode.org/wiki/Modular_exponentiation	Modular exponentiation	Find the last 40 decimal digits of a b {\displaystyle a^{b}} , where a = 2988348162058574136915891421498819466320163312926952423791023078876139 {\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139} b = 235139930337346448646612254452369009474497523...	#Scheme	Scheme	(define (square n) (* n n)) (define (mod-exp a n mod) (cond ((= n 0) 1) ((even? n) (remainder (square (mod-exp a (/ n 2) mod)) mod)) (else (remainder (* a (mod-exp a (- n 1) mod)) mod)))) (define result (mod-exp 29883481620585741369158...	Give a code snippet in #Scheme Find the last 40 decimal digits of a b {\displaystyle a^{b}} , where a = 2988348162058574136915891421498819466320163312926952423791023078876139 {\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139} b = 2351399303373...	christopher/rosetta-code
http://rosettacode.org/wiki/Boolean_values	Boolean values	Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks Logical operations	#Z80_Assembly	Z80 Assembly	BIT 0,A jr nz,true ;;;;;;;;;;;;;;;; AND 1 jr nz,true ;;;;;;;;;;;;;;;; RRCA jr c,true	Give a code snippet in #Z80_Assembly Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks Logical operations	christopher/rosetta-code

http://rosettacode.org/wiki/Arithmetic-geometric_mean

Arithmetic-geometric mean

This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. 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) Task Write a function to compute the arithmetic-geomet...

#ZX_Spectrum_Basic

ZX Spectrum Basic

10 LET a=1: LET g=1/SQR 2 20 LET ta=a 30 LET a=(a+g)/2 40 LET g=SQR (ta*g) 50 IF a<ta THEN GO TO 20 60 PRINT a

Give a code snippet in #ZX_Spectrum_Basic This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. 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) Task Write ...

christopher/rosetta-code

http://rosettacode.org/wiki/Josephus_problem

Josephus problem

Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\displaystyle 0} , removing eve...

#Perl

Perl

my @prisoner = 0 .. 40; my $k = 3; until (@prisoner == 1) { push @prisoner, shift @prisoner for 1 .. $k-1; shift @prisoner; } print "Prisoner @prisoner survived.\n"

Give a code snippet in #Perl Josephus problem is a math puzzle with a grim description: n {\displaystyle n} prisoners are standing on a circle, sequentially numbered from 0 {\displaystyle 0} to n − 1 {\displaystyle n-1} . An executioner walks along the circle, starting from prisoner 0 {\d...

christopher/rosetta-code

http://rosettacode.org/wiki/Sorting_algorithms/Quicksort

Sorting algorithms/Quicksort

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#Curry

Curry

-- quicksort using higher-order functions: qsort :: [Int] -> [Int] qsort [] = [] qsort (x:l) = qsort (filter (<x) l) ++ x : qsort (filter (>=x) l) goal = qsort [2,3,1,0]

Give a code snippet in #Curry Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick so...

christopher/rosetta-code

http://rosettacode.org/wiki/Bitwise_operations

Bitwise operations

Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...

#Standard_ML

Standard ML

fun bitwise_ints (a, b) = ( print ("a and b: " ^ IntInf.toString (IntInf.andb (IntInf.fromInt a, IntInf.fromInt b)) ^ "\n"); print ("a or b: " ^ IntInf.toString (IntInf.orb (IntInf.fromInt a, IntInf.fromInt b)) ^ "\n"); print ("a xor b: " ^ IntInf.toString (IntInf.xorb (IntInf.fromInt a, IntInf.fromInt b)) ^ "\...

Give a code snippet in #Standard_ML Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Opera...

christopher/rosetta-code

http://rosettacode.org/wiki/Fractran

Fractran

FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway. A FRACTRAN program is an ordered list of positive fractions P = ( f 1 , f 2 , … , f m ) {\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})} , together with an initial positive integer input n ...

#OCaml

OCaml

open Num let get_input () = num_of_int ( try int_of_string Sys.argv.(1) with _ -> 10) let get_max_steps () = try int_of_string Sys.argv.(2) with _ -> 50 let read_program () = let line = read_line () in let words = Str.split (Str.regexp " +") line in List.map num_of_string words let i...

Give a code snippet in #OCaml FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway. A FRACTRAN program is an ordered list of positive fractions P = ( f 1 , f 2 , … , f m ) {\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})} , together with an initia...

christopher/rosetta-code

http://rosettacode.org/wiki/XML/Output

XML/Output

Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks. All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> element. As an example, calling ...

#OCaml

OCaml

# #directory "+xml-light" (* or maybe "+site-lib/xml-light" *) ;; # #load "xml-light.cma" ;; # let data = [ ("April", "Bubbly: I'm > Tam and <= Emily"); ("Tam O'Shanter", "Burns: \"When chapman billies leave the street ...\""); ("Emily", "Short & shrift"); ] in let tags = List.map (fun (name, co...

Give a code snippet in #OCaml Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks. All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> el...

christopher/rosetta-code

http://rosettacode.org/wiki/Dijkstra%27s_algorithm

Dijkstra's algorithm

This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the single-source shortest path pro...

#Sidef

Sidef

class Graph(*args) { struct Node { String name, Array edges = [], Number dist = Inf, prev = nil, Bool visited = false, } struct Edge { Number weight, Node vertex, } has g = Hash() method init { args.each { |a| se...

Give a code snippet in #Sidef This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Dijkstra's algorithm, conceived by Dutch computer scientist Edsger Dijkstra in 1956 and published in 1959, is a graph search algorithm that solves the ...

christopher/rosetta-code

http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously

Loop over multiple arrays simultaneously

Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: ...

#Picat

Picat

import util. go => L1 = ["a","b","c"], L2 = ["A","B","C"], L3 = ["1","2","3"], println("foreach loop:"), foreach({A,B,C} in zip(L1,L2,L3)) println([A,B,C].join('')) end, nl, println("list comprehension/n:"), println( [[A,B,C].join('') : {A,B,C} in zip(L1,L2,L3)].join("\n")), nl, % W...

Give a code snippet in #Picat Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this exam...

christopher/rosetta-code

http://rosettacode.org/wiki/Sorting_algorithms/Bogosort

Sorting algorithms/Bogosort

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#Modula-3

Modula-3

MODULE Bogo EXPORTS Main; IMPORT IO, Fmt, Random; VAR a := ARRAY [1..5] OF INTEGER {1, 2, 3, 4, 5}; count := 0; PROCEDURE Shuffle(VAR a: ARRAY OF INTEGER) = VAR temp: INTEGER; BEGIN WITH rand = NEW(Random.Default).init() DO FOR i := FIRST(a) TO LAST(a) - 1 DO WITH j = rand.integer(i, LAS...

Give a code snippet in #Modula-3 Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick...

christopher/rosetta-code

http://rosettacode.org/wiki/Reverse_a_string

Reverse a string

Task Take a string and reverse it. For example, "asdf" becomes "fdsa". Extra credit Preserve Unicode combining characters. For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa". Other tasks related to string operations: Metrics Array length String length Copy a string Empty string (assignment) Counting ...

#Delphi

Delphi

function ReverseString(const InString: string): string; var i: integer; begin for i := Length(InString) downto 1 do Result := Result + InString[i]; end;

Give a code snippet in #Delphi Task Take a string and reverse it. For example, "asdf" becomes "fdsa". Extra credit Preserve Unicode combining characters. For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa". Other tasks related to string operations: Metrics Array length String length Copy a string Empt...

christopher/rosetta-code

http://rosettacode.org/wiki/Fork

Fork

Task Spawn a new process which can run simultaneously with, and independently of, the original parent process.

#DCL

DCL

$! looper.com procedure $ i = 10 $ loop: $ show time $ wait 'p1 $ i = i - 1 $ if i .gt. 0 then $ goto loop

Give a code snippet in #DCL Task Spawn a new process which can run simultaneously with, and independently of, the original parent process.

christopher/rosetta-code

http://rosettacode.org/wiki/Sum_and_product_of_an_array

Sum and product of an array

Task Compute the sum and product of an array of integers.

#Sidef

Sidef

var ary = [1, 2, 3, 4, 5]; say ary.sum; # => 15 say ary.prod; # => 120

Give a code snippet in #Sidef Task Compute the sum and product of an array of integers.

christopher/rosetta-code

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...

#Elixir

Elixir

defmodule Gray_code do use Bitwise def encode(n), do: bxor(n, bsr(n,1)) def decode(g), do: decode(g,0) def decode(0,n), do: n def decode(g,n), do: decode(bsr(g,1), bxor(g,n)) end Enum.each(0..31, fn(n) -> g = Gray_code.encode(n) d = Gray_code.decode(g) :io.fwrite("~2B : ~5.2.0B : ~5.2.0B : ~5.2.0B...

Give a code snippet in #Elixir 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...

christopher/rosetta-code

http://rosettacode.org/wiki/Loops/For

Loops/For

“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code. Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers. ...

#Zig

Zig

const std = @import("std"); pub fn main() !void { const stdout_wr = std.io.getStdOut().writer(); var i: u8 = 1; while (i < 5) : (i += 1) { var j: u8 = 1; while (j <= i) : (j += 1) try stdout_wr.writeAll("*"); try stdout_wr.writeAll("\n"); } }

Give a code snippet in #Zig “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code. Common extensions of this allow other counting patterns or iterating over abstract structure...

christopher/rosetta-code

http://rosettacode.org/wiki/Execute_HQ9%2B

Execute HQ9+

Task Implement a HQ9+ interpreter or compiler.

#MiniScript

MiniScript

code = input("Enter HQ9+ program: ") sing = function() for i in range(99,2) print i + " bottles of beer on the wall, " + i + " bottles of beer" print "Take one down, pass it around, " + (i-1) + " bottle" + "s"*(i>2) + " of beer on the wall" end for print "1 bottle of beer on the wall, 1 bo...

Give a code snippet in #MiniScript Task Implement a HQ9+ interpreter or compiler.

christopher/rosetta-code

http://rosettacode.org/wiki/Trigonometric_functions

Trigonometric functions

Task If your language has a library or built-in functions for trigonometry, show examples of: sine cosine tangent inverses (of the above) using the same angle in radians and degrees. For the non-inverse functions, each radian/degree pair should use arguments that evaluate to the same angle (that i...

#Axe

Axe

Disp sin(43)▶Dec,i Disp cos(43)▶Dec,i Disp tan⁻¹(10,10)▶Dec,i

Give a code snippet in #Axe Task If your language has a library or built-in functions for trigonometry, show examples of: sine cosine tangent inverses (of the above) using the same angle in radians and degrees. For the non-inverse functions, each radian/degree pair should use arguments that evaluat...

christopher/rosetta-code

http://rosettacode.org/wiki/Loops/Infinite

Loops/Infinite

Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within l...

#AutoHotkey

AutoHotkey

Loop MsgBox SPAM `n

Give a code snippet in #AutoHotkey Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach ...

christopher/rosetta-code

http://rosettacode.org/wiki/String_matching

String matching

Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...

#D

D

void main() { import std.stdio; import std.algorithm: startsWith, endsWith, find, countUntil; "abcd".startsWith("ab").writeln; // true "abcd".endsWith("zn").writeln; // false "abab".find("bb").writeln; // empty array (no match) "abcd".find("bc").writeln; // "b...

Give a code snippet in #D Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Conc...

christopher/rosetta-code

http://rosettacode.org/wiki/Mutual_recursion

Mutual recursion

Two functions are said to be mutually recursive if the first calls the second, and in turn the second calls the first. Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as: F ( 0 ) = 1 ; M ( 0 ) = 0 F ( n ) = n − M ( F ( n − 1 ) ) , ...

#CoffeeScript

CoffeeScript

F = (n) -> if n is 0 then 1 else n - M F n - 1 M = (n) -> if n is 0 then 0 else n - F M n - 1 console.log [0...20].map F console.log [0...20].map M

Give a code snippet in #CoffeeScript Two functions are said to be mutually recursive if the first calls the second, and in turn the second calls the first. Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as: F ( 0 ) = 1 ; M ( 0 ) = 0 ...

christopher/rosetta-code

http://rosettacode.org/wiki/Sequence_of_non-squares

Sequence of non-squares

Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for n in the range 1 to 22 Show that no squares occur for n less than one million This is sequence A000037 in the OEIS database.

#Nim

Nim

import math, strutils func nosqr(n: int): seq[int] = result = newSeq[int](n) for i in 1..n: result[i - 1] = i + i.float.sqrt.toInt func issqr(n: int): bool = sqrt(float(n)).splitDecimal().floatpart < 1e-7 echo "Sequence for n = 22:" echo nosqr(22).join(" ") for i in nosqr(1_000_000 - 1): assert no...

Give a code snippet in #Nim Task Show that the following remarkable formula gives the sequence of non-square natural numbers: n + floor(1/2 + sqrt(n)) Print out the values for n in the range 1 to 22 Show that no squares occur for n less than one million This is sequence A000037 ...

christopher/rosetta-code

http://rosettacode.org/wiki/Loops/Increment_loop_index_within_loop_body

Loops/Increment loop index within loop body

Sometimes, one may need (or want) a loop which its iterator (the index variable) is modified within the loop body in addition to the normal incrementation by the (do) loop structure index. Goal Demonstrate the best way to accomplish this. Task Write a loop which: starts the index (variable...

#C.2B.2B

C++

#include "stdafx.h" #include <iostream> #include <math.h> using namespace std; bool isPrime(double number) { for (double i = number - 1; i >= 2; i--) { if (fmod(number, i) == 0) return false; } return true; } int main() { double i = 42; int n = 0; while (n < 42) { ...

Give a code snippet in #C.2B.2B Sometimes, one may need (or want) a loop which its iterator (the index variable) is modified within the loop body in addition to the normal incrementation by the (do) loop structure index. Goal Demonstrate the best way to accomplish this. Task Write a loop whic...

christopher/rosetta-code

http://rosettacode.org/wiki/Juggler_sequence

Juggler sequence

Background of the juggler sequence: Juggler sequences were publicized by an American mathematician and author Clifford A. Pickover. The name of the sequence gets it's name from the similarity of the rising and falling nature of the numbers in the sequences, much like balls in the hands of a juggler. Descrip...

#Haskell

Haskell

import Text.Printf import Data.List juggler :: Integer -> [Integer] juggler = takeWhile (> 1) . iterate (\x -> if odd x then isqrt (x*x*x) else isqrt x) task :: Integer -> IO () task n = printf s n (length ns + 1) (i :: Int) (show...

Give a code snippet in #Haskell Background of the juggler sequence: Juggler sequences were publicized by an American mathematician and author Clifford A. Pickover. The name of the sequence gets it's name from the similarity of the rising and falling nature of the numbers in the sequences, much like balls in t...

christopher/rosetta-code

http://rosettacode.org/wiki/Palindrome_detection

Palindrome detection

A palindrome is a phrase which reads the same backward and forward. Task[edit] Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes) is a palindrome. For extra credit: Support Unicode characters. Write a second function (possibly as a wrapper to the first) which ...

#FBSL

FBSL

#APPTYPE CONSOLE FUNCTION stripNonAlpha(BYVAL s AS STRING) AS STRING DIM sTemp AS STRING = "" DIM c AS STRING FOR DIM i = 1 TO LEN(s) c = MID(s, i, 1) IF INSTR("ABCDEFGHIJKLMNOPQRSTUVWXYZ", c, 0, 1) THEN sTemp = stemp & c END IF NEXT RETURN sTemp END FUNCTION FUNCTION IsPalindrome(BYVAL s AS STRING) A...

Give a code snippet in #FBSL A palindrome is a phrase which reads the same backward and forward. Task[edit] Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes) is a palindrome. For extra credit: Support Unicode characters. Write a second function (possibly as ...

christopher/rosetta-code

http://rosettacode.org/wiki/Horizontal_sundial_calculations

Horizontal sundial calculations

Task Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location. For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit...

#Tcl

Tcl

set PI 3.1415927 fconfigure stdout -buffering none puts -nonewline "Enter latitude => "; gets stdin lat puts -nonewline "Enter longitude => "; gets stdin lng puts -nonewline "Enter legal meridian => "; gets stdin ref puts "" set slat [expr {sin($lat*$PI/180)}] puts [format " sine of latitude: %8g" $sl...

Give a code snippet in #Tcl Task Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location. For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, ...

christopher/rosetta-code

http://rosettacode.org/wiki/Read_a_file_character_by_character/UTF8

Read a file character by character/UTF8

Task Read a file one character at a time, as opposed to reading the entire file at once. The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached). The procedure should support the reading of files contain...

#Run_BASIC

Run BASIC

open file.txt" for binary as #f numChars = 1 ' specify number of characters to read a$ = input$(#f,numChars) ' read number of characters specified b$ = input$(#f,1) ' read one character close #f

Give a code snippet in #Run_BASIC Task Read a file one character at a time, as opposed to reading the entire file at once. The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached). The procedure should s...

christopher/rosetta-code

http://rosettacode.org/wiki/100_doors

100 doors

There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it). The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it. The third...

#Ada

Ada

with Ada.Text_Io; use Ada.Text_Io; procedure Doors is type Door_State is (Closed, Open); type Door_List is array(Positive range 1..100) of Door_State; The_Doors : Door_List := (others => Closed); begin for I in 1..100 loop for J in The_Doors'range loop if J mod I = 0 then ...

Give a code snippet in #Ada There are 100 doors in a row that are all initially closed. You make 100 passes by the doors. The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it). The second time, only visit every 2nd door (door #2, #4, #6, ...)...

christopher/rosetta-code

http://rosettacode.org/wiki/Ethiopian_multiplication

Ethiopian multiplication

Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving. Method: Take two numbers to be multiplied and write them down at the top of two columns. In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ...

#VBScript

VBScript

option explicit class List private theList private nOccupiable private nTop sub class_initialize nTop = 0 nOccupiable = 100 redim theList( nOccupiable ) end sub public sub store( x ) if nTop >= nOccupiable then nOccupiable = nOccupiable + 100 redim preserve theList( nOccupiable ) end if th...

Give a code snippet in #VBScript Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving. Method: Take two numbers to be multiplied and write them down at the top of two columns. In the left-hand column repeatedly halve the last number, discarding any remainders, an...

christopher/rosetta-code

http://rosettacode.org/wiki/Kronecker_product_based_fractals

Kronecker product based fractals

This task is based on Kronecker product of two matrices. If your language has no a built-in function for such product then you need to implement it first. The essence of fractals is self-replication (at least, self-similar replications). So, using n times self-product of the matrix (filled with 0/1) we ...

#Action.21

Action!

SET EndProg=*

Give a code snippet in #Action.21 This task is based on Kronecker product of two matrices. If your language has no a built-in function for such product then you need to implement it first. The essence of fractals is self-replication (at least, self-similar replications). So, using n times self-product of t...

christopher/rosetta-code

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), b...

#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....

Give a code snippet in #Java 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 sc...

christopher/rosetta-code

http://rosettacode.org/wiki/Towers_of_Hanoi

Towers of Hanoi

Task Solve the Towers of Hanoi problem with recursion.

#Delphi

Delphi

proc move(byte n, src, via, dest) void: if n>0 then move(n-1, src, dest, via); writeln("Move disk from pole ",src," to pole ",dest); move(n-1, via, src, dest) fi corp proc nonrec main() void: move(4, 1, 2, 3) corp

Give a code snippet in #Delphi Task Solve the Towers of Hanoi problem with recursion.

christopher/rosetta-code

http://rosettacode.org/wiki/Summarize_and_say_sequence

Summarize and say sequence

There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits: 0, 10, 1110, 3110, 132110, 1113122110, 311311222110 ... The terms generat...

#Racket

Racket

#lang racket (define (next s) (define v (make-vector 10 0)) (for ([c s]) (define d (- (char->integer #\9) (char->integer c))) (vector-set! v d (add1 (vector-ref v d)))) (string-append* (for/list ([x v] [i (in-range 9 -1 -1)] #:when (> x 0)) (format "~a~a" x i)))) (define (seq-of ...

Give a code snippet in #Racket There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits: 0, 10, 1110, 3110, 132110, 1113122110, 311...

christopher/rosetta-code

http://rosettacode.org/wiki/Here_document

Here document

A here document (or "heredoc") is a way of specifying a text block, preserving the line breaks, indentation and other whitespace within the text. Depending on the language being used, a here document is constructed using a command followed by "<<" (or some other symbol) followed by a token string. The text ...

#FreeBASIC

FreeBASIC

Dim As String text1 = " " & Chr(10) & _ "<<'FOO' " & Chr(10) & _ " 'jaja', `esto`" & Chr(10) & _ " <simula>" & Chr(10) & _ " \un\" & Chr(10) & _ !" ${ejemplo} de \"heredoc\"" & Chr(10) & _ " en FreeBASIC." Dim As String text2 = "Esta es la primera linea." & Chr(10) & _ "Esta es la segunda linea." & Chr(10) & _...

Give a code snippet in #FreeBASIC A here document (or "heredoc") is a way of specifying a text block, preserving the line breaks, indentation and other whitespace within the text. Depending on the language being used, a here document is constructed using a command followed by "<<" (or some other symbol) fol...

christopher/rosetta-code

http://rosettacode.org/wiki/Barnsley_fern

Barnsley fern

A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS). Task Create this fractal fern, using the following transformations: ƒ1 (chosen 1% of the time) xn + 1 = 0 yn + 1 = 0.16 yn ƒ2 (chosen 85% of the time) ...

#Ring

Ring

Load "guilib.ring" /* +--------------------------------------------------------------------------- + Program Name : Draw Barnsley Fern + Purpose : Draw Fern using Quadratic Equation and Random Number +--------------------------------------------------------------------------- */ ###------...

Give a code snippet in #Ring A Barnsley fern is a fractal named after British mathematician Michael Barnsley and can be created using an iterated function system (IFS). Task Create this fractal fern, using the following transformations: ƒ1 (chosen 1% of the time) xn + 1 = 0 yn + 1 = 0.16 yn ...

christopher/rosetta-code

http://rosettacode.org/wiki/Strip_comments_from_a_string

Strip comments from a string

Strip comments from a string You are encouraged to solve this task according to the task description, using any language you may know. The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line. Whitespace debacle: There is s...

#JavaScript

JavaScript

function stripComments(s) { var re1 = /^\s+|\s+$/g; // Strip leading and trailing spaces var re2 = /\s*[#;].+$/g; // Strip everything after # or ; to the end of the line, including preceding spaces return s.replace(re1,'').replace(re2,''); } var s1 = 'apples, pears # and bananas'; var s2 = 'apples, pears ; a...

Give a code snippet in #JavaScript Strip comments from a string You are encouraged to solve this task according to the task description, using any language you may know. The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line...

christopher/rosetta-code

http://rosettacode.org/wiki/Additive_primes

Additive primes

Definitions In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes. Task Write a program to determine (and show here) all additive primes less than 500. Optionally, show the number of additive primes. Also see the OEIS entry: A046704 additive primes. ...

#BASIC

BASIC

10 DEFINT A-Z: E=500 20 DIM P(E): P(0)=-1: P(1)=-1 30 FOR I=2 TO SQR(E) 40 IF NOT P(I) THEN FOR J=I*2 TO E STEP I: P(J)=-1: NEXT 50 NEXT 60 FOR I=B TO E: IF P(I) GOTO 100 70 J=I: S=0 80 IF J>0 THEN S=S+J MOD 10: J=J\10: GOTO 80 90 IF NOT P(S) THEN N=N+1: PRINT I, 100 NEXT 110 PRINT: PRINT N;" additive primes found belo...

Give a code snippet in #BASIC Definitions In mathematics, additive primes are prime numbers for which the sum of their decimal digits are also primes. Task Write a program to determine (and show here) all additive primes less than 500. Optionally, show the number of additive primes. Also see the OEIS entry:...

christopher/rosetta-code

http://rosettacode.org/wiki/Department_numbers

Department numbers

There is a highly organized city that has decided to assign a number to each of their departments: police department sanitation department fire department Each department can have a number between 1 and 7 (inclusive). The three department numbers are to be unique (different from each other) and mu...

#Clojure

Clojure

(let [n (range 1 8)] (for [police n sanitation n fire n :when (distinct? police sanitation fire) :when (even? police) :when (= 12 (+ police sanitation fire))] (println police sanitation fire)))

Give a code snippet in #Clojure There is a highly organized city that has decided to assign a number to each of their departments: police department sanitation department fire department Each department can have a number between 1 and 7 (inclusive). The three department numbers are to be unique (...

christopher/rosetta-code

http://rosettacode.org/wiki/Compiler/AST_interpreter

Compiler/AST interpreter

An AST interpreter interprets an Abstract Syntax Tree (AST) produced by a Syntax Analyzer. Task[edit] Take the AST output from the Syntax analyzer task, and interpret it as appropriate. Refer to the Syntax analyzer task for details of the AST. Loading the AST from the syntax analyzer is as simple as (pseudo code) de...

#Perl

Perl

#!/usr/bin/perl use strict; # interpreter.pl - execute a flatAST use warnings; # http://www.rosettacode.org/wiki/Compiler/AST_interpreter use integer; my %variables; tree()->run; sub tree { my $line = <> // die "incomplete tree\n"; (local $_, my $arg) = $line =~ /^(\w+|;)\s+(.*)/ or die "bad input $line...

Give a code snippet in #Perl An AST interpreter interprets an Abstract Syntax Tree (AST) produced by a Syntax Analyzer. Task[edit] Take the AST output from the Syntax analyzer task, and interpret it as appropriate. Refer to the Syntax analyzer task for details of the AST. Loading the AST from the syntax analyzer is ...

christopher/rosetta-code

http://rosettacode.org/wiki/Fibonacci_sequence

Fibonacci sequence

The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...

#LOLCODE

LOLCODE

HAI 1.2 HOW DUZ I fibonacci YR N EITHER OF BOTH SAEM N AN 1 AN BOTH SAEM N AN 0 O RLY? YA RLY, FOUND YR 1 NO WAI I HAS A N1 I HAS A N2 N1 R DIFF OF N AN 1 N2 R DIFF OF N AN 2 N1 R fibonacci N1 N2 R fibonacci N2 FOUND YR SUM OF N1 AN N2 OIC IF U SAY SO KTHXBYE

Give a code snippet in #LOLCODE The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solutions a...

christopher/rosetta-code

http://rosettacode.org/wiki/Loop_over_multiple_arrays_simultaneously

Loop over multiple arrays simultaneously

Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this example, loop over the arrays: ...

#ALGOL_W

ALGOL W

begin % declare the three arrays % string(1) array a, b ( 1 :: 3 ); integer array c ( 1 :: 3 ); % initialise the arrays - have to do this element by element in Algol W % a(1) := "a"; a(2) := "b"; a(3) := "c"; b(1) := "A"; b(2) := "B"; b(3) := "...

Give a code snippet in #ALGOL_W Task Loop over multiple arrays (or lists or tuples or whatever they're called in your language) and display the i th element of each. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. For this ex...

christopher/rosetta-code

http://rosettacode.org/wiki/Hello_world/Newline_omission

Hello world/Newline omission

Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output. Task Display the string Goodbye, World! without a trailing newline. Related tasks Hello world/Graphical Hello world/Line Printer Hello world/Standard error Hello world/Text

#Neko

Neko

/** hellonnl.neko Tectonics: nekoc hellonnl.neko neko hellonnl -or- nekoc hellonnl.neko nekotools boot hellonnl.n ./hellonnl */ $print("Goodbye, World!");

Give a code snippet in #Neko Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output. Task Display the string Goodbye, World! without a trailing newline. Related tasks Hello world/Graphical Hello world/Line Printer Hello world/Standa...

christopher/rosetta-code

http://rosettacode.org/wiki/Forest_fire

Forest fire

This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and Schwabl definition of the fores...

#Ruby

Ruby

class Forest_Fire Neighborhood = [-1,0,1].product([-1,0,1]) - [0,0] States = {empty:" ", tree:"T", fire:"#"} def initialize(xsize, ysize=xsize, p=0.5, f=0.01) @xsize, @ysize, @p, @f = xsize, ysize, p, f @field = Array.new(xsize+1) {|i| Array.new(ysize+1, :empty)} @generation = 0 end def evolve...

Give a code snippet in #Ruby This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and S...

christopher/rosetta-code

http://rosettacode.org/wiki/Ordered_words

Ordered words

An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally assume that you have download...

#XPL0

XPL0

string 0; \use zero-terminated strings int MaxLen, Pass, I, Ch, Ch0; char Word(25); def LF=$0A, CR=$0D, EOF=$1A; [FSet(FOpen("unixdict.txt", 0), ^I); MaxLen:= 0; for Pass:= 1 to 2 do [OpenI(3); repeat I:= 0; Ch0:= 0; loop [repeat Ch:= ChIn(3) until Ch # CR; ...

Give a code snippet in #XPL0 An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally...

christopher/rosetta-code

http://rosettacode.org/wiki/Multifactorial

Multifactorial

The factorial of a number, written as n ! {\displaystyle n!} , is defined as n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displaystyle n!=n(n-1)(n-2)...(2)(1)} . Multifactorials generalize factorials as follows: n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displaystyle n!=n(n-1)(n-2)...(2)(...

#GAP

GAP

MultiFactorial := function(n, k) local r; r := 1; while n > 1 do r := r*n; n := n - k; od; return r; end; PrintArray(List([1 .. 10], n -> List([1 .. 5], k -> MultiFactorial(n, k)))); [ [ 1, 1, 1, 1, 1 ], [ 2, 2, 2, 2,...

Give a code snippet in #GAP The factorial of a number, written as n ! {\displaystyle n!} , is defined as n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displaystyle n!=n(n-1)(n-2)...(2)(1)} . Multifactorials generalize factorials as follows: n ! = n ( n − 1 ) ( n − 2 ) . . . ( 2 ) ( 1 ) {\displ...

christopher/rosetta-code

http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers

Luhn test of credit card numbers

The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order of the digits in the number. Tak...

#Swift

Swift

func luhn(_ number: String) -> Bool { return number.reversed().enumerated().map({ let digit = Int(String($0.element))! let even = $0.offset % 2 == 0 return even ? digit : digit == 9 ? 9 : digit * 2 % 9 }).reduce(0, +) % 10 == 0 } luhn("49927398716") // true luhn("49927398717") // false

Give a code snippet in #Swift The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits. Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test: Reverse the order of...

christopher/rosetta-code

http://rosettacode.org/wiki/Base64_decode_data

Base64 decode data

See Base64 encode data. Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file. When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output with incorrect padding. Obviously...

#zkl

zkl

var [const] MsgHash=Import("zklMsgHash"), Curl=Import("zklCurl"); icon:=Curl().get("http://rosettacode.org/favicon.ico"); //-->(Data(4,331),693,0) icon=icon[0][icon[1],*]; // remove header iconEncoded:=MsgHash.base64encode(icon); iconDecoded:=MsgHash.base64decode(iconEncoded); File("rosettaCodeIcon.ico","wb").write(i...

Give a code snippet in #zkl See Base64 encode data. Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file. When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output with...

christopher/rosetta-code

http://rosettacode.org/wiki/Send_an_unknown_method_call

Send an unknown method call

Task Invoke an object method where the name of the method to be invoked can be generated at run time. Related tasks Respond to an unknown method call. Runtime evaluation

#Logtalk

Logtalk

:- object(foo). :- public(bar/1). bar(42). :- end_object.

Give a code snippet in #Logtalk Task Invoke an object method where the name of the method to be invoked can be generated at run time. Related tasks Respond to an unknown method call. Runtime evaluation

christopher/rosetta-code

http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort

Sorting algorithms/Selection sort

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#Io

Io

List do ( selectionSortInPlace := method( size repeat(idx, swapIndices(idx, indexOf(slice(idx, size) min)) ) ) ) l := list(-1, 4, 2, -9) l selectionSortInPlace println # ==> list(-9, -1, 2, 4)

Give a code snippet in #Io Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort ...

christopher/rosetta-code

http://rosettacode.org/wiki/Spiral_matrix

Spiral matrix

Task Produce a spiral array. A spiral array is a square arrangement of the first N2 natural numbers, where the numbers increase sequentially as you go around the edges of the array spiraling inwards. For example, given 5, produce this array: 0 1 2 3 4 15 16 17 18 5 14 23 24 19 6 13 22 21 ...

#IS-BASIC

IS-BASIC

100 PROGRAM "SpiralMa.bas" 110 TEXT 80 120 INPUT PROMPT "Enter size of matrix (max. 10): ":N 130 NUMERIC A(1 TO N,1 TO N) 140 CALL INIT(A) 150 CALL WRITE(A) 160 DEF INIT(REF T) 170 LET BCOL,BROW,COL,ROW=1:LET TCOL,TROW=N:LET DIR=0 180 FOR I=0 TO N^2-1 190 LET T(COL,ROW)=I 200 SELECT CASE DIR 210 CASE 0 ...

Give a code snippet in #IS-BASIC Task Produce a spiral array. A spiral array is a square arrangement of the first N2 natural numbers, where the numbers increase sequentially as you go around the edges of the array spiraling inwards. For example, given 5, produce this array: 0 1 2 3 4 15 16...

christopher/rosetta-code

http://rosettacode.org/wiki/Loops/For_with_a_specified_step

Loops/For with a specified step

Task Demonstrate a for-loop where the step-value is greater than one. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within loop b...

#Never

Never

for (i = 0; i < 10; i += 3)

Give a code snippet in #Never Task Demonstrate a for-loop where the step-value is greater than one. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Inc...

christopher/rosetta-code

http://rosettacode.org/wiki/M%C3%B6bius_function

Möbius function

The classical Möbius function: μ(n) is an important multiplicative function in number theory and combinatorics. There are several ways to implement a Möbius function. A fairly straightforward method is to find the prime factors of a positive integer n, then define μ(n) based on the sum of the primitive factors. It ha...

#GW-BASIC

GW-BASIC

10 FOR T = 0 TO 9 20 FOR U = 1 TO 10 30 N = 10*T + U 40 GOSUB 100 50 PRINT USING "## ";M; 60 NEXT U 70 PRINT 80 NEXT T 90 END 100 IF N = 1 THEN M = 1 : RETURN 110 M = 1 : F = 2 120 IF N MOD (F*F) = 0 THEN M = 0 : RETURN 130 IF N MOD F = 0 THEN GOSUB 170 140 F = F + 1 150 IF F <= N THEN GOTO 120 160 RETURN 170 M = -M 1...

Give a code snippet in #GW-BASIC The classical Möbius function: μ(n) is an important multiplicative function in number theory and combinatorics. There are several ways to implement a Möbius function. A fairly straightforward method is to find the prime factors of a positive integer n, then define μ(n) based on the s...

christopher/rosetta-code

http://rosettacode.org/wiki/Hello_world/Newbie

Hello world/Newbie

Task Guide a new user of a language through the steps necessary to install the programming language and selection of a text editor if needed, to run the languages' example in the Hello world/Text task. Assume the language-newbie is a programmer in another language. Assume the language-newbie is competent in install...

#BQN

BQN

rlwrap ./BQN

Give a code snippet in #BQN Task Guide a new user of a language through the steps necessary to install the programming language and selection of a text editor if needed, to run the languages' example in the Hello world/Text task. Assume the language-newbie is a programmer in another language. Assume the language-n...

christopher/rosetta-code

http://rosettacode.org/wiki/Truncatable_primes

Truncatable primes

A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 7...

#PowerShell

PowerShell

function IsPrime ( [int] $num ) { $isprime = @{} 2..[math]::sqrt($num) | Where-Object { $isprime[$_] -eq $null } | ForEach-Object { $_ $isprime[$_] = $true for ( $i=$_*$_ ; $i -le $num; $i += $_ ) { $isprime[$i] = $false } } 2..$num | Where-Object { $isprime[$_] -...

Give a code snippet in #PowerShell A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-trun...

christopher/rosetta-code

http://rosettacode.org/wiki/Null_object

Null object

Null (or nil) is the computer science concept of an undefined or unbound object. Some languages have an explicit way to access the null object, and some don't. Some languages distinguish the null object from undefined values, and some don't. Task Show how to access null in your language by checking to see if an ob...

#langur

langur

val .x, .y = true, null writeln .x == null writeln .y == null writeln .x ==? null writeln .y ==? null # null not a "truthy" result writeln if(null: 0; 1)

Give a code snippet in #langur Null (or nil) is the computer science concept of an undefined or unbound object. Some languages have an explicit way to access the null object, and some don't. Some languages distinguish the null object from undefined values, and some don't. Task Show how to access null in your lang...

christopher/rosetta-code

http://rosettacode.org/wiki/Longest_common_substring

Longest common substring

Task Write a function that returns the longest common substring of two strings. Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing". Note that substrings are consecutive characters within a string....

#VBScript

VBScript

Function lcs(string1,string2) For i = 1 To Len(string1) tlcs = tlcs & Mid(string1,i,1) If InStr(string2,tlcs) Then If Len(tlcs) > Len(lcs) Then lcs = tlcs End If Else tlcs = "" End If Next End Function WScript.Echo lcs(WScript.Arguments(0),WScript.Arguments(1))

Give a code snippet in #VBScript Task Write a function that returns the longest common substring of two strings. Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing". Note that substrings are conse...

christopher/rosetta-code

http://rosettacode.org/wiki/Sorting_algorithms/Bogosort

Sorting algorithms/Bogosort

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#PHP

PHP

function bogosort($l) { while (!in_order($l)) shuffle($l); return $l; } function in_order($l) { for ($i = 1; $i < count($l); $i++) if ($l[$i] < $l[$i-1]) return FALSE; return TRUE; }

Give a code snippet in #PHP Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort...

christopher/rosetta-code

http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation

Horner's rule for polynomial evaluation

A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...

#FunL

FunL

import lists.foldr def horner( poly, x ) = foldr( \a, b -> a + b*x, 0, poly ) println( horner([-19, 7, -4, 6], 3) )

Give a code snippet in #FunL A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\d...

christopher/rosetta-code

http://rosettacode.org/wiki/Sort_an_array_of_composite_structures

Sort an array of composite structures

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#Rust

Rust

use std::cmp::Ordering; #[derive(Debug)] struct Employee { name: String, category: String, } impl Employee { fn new(name: &str, category: &str) -> Self { Employee { name: name.into(), category: category.into(), } } } impl PartialEq for Employee { fn eq(&...

Give a code snippet in #Rust Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sor...

christopher/rosetta-code

http://rosettacode.org/wiki/Population_count

Population count

Population count You are encouraged to solve this task according to the task description, using any language you may know. The population count is the number of 1s (ones) in the binary representation of a non-negative integer. Population count is also known as: pop count popcount sideways sum ...

#8086_Assembly

8086 Assembly

cpu 8086 bits 16 org 100h section .text ;;; Calculate hamming weights of 3^0 to 3^29. ;;; 3^29 needs a 48-bit representation, which ;;; we'll put in BP:SI:DI. xor bp,bp ; BP:SI:DI = 1 xor si,si xor di,di inc di mov cx,30 ;;; Calculate pop count of BP:SI:DI pow3s: push bp ; Keep state push si push di xo...

Give a code snippet in #8086_Assembly Population count You are encouraged to solve this task according to the task description, using any language you may know. The population count is the number of 1s (ones) in the binary representation of a non-negative integer. Population count is also known as: p...

christopher/rosetta-code

http://rosettacode.org/wiki/Ray-casting_algorithm

Ray-casting algorithm

This page uses content from Wikipedia. The original article was at Point_in_polygon. 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) Given a point and a polygon, check if the point is inside or out...

#REXX

REXX

/*REXX program verifies if a horizontal ray from point P intersects a polygon. */ call points 5 5, 5 8, -10 5, 0 5, 10 5, 8 5, 10 10 A= 2.5; B= 7.5 /* ◄───── used for shorter arguments (below).*/ call poly 0 0, 10 0, 10 10, 0 10 ...

Give a code snippet in #REXX This page uses content from Wikipedia. The original article was at Point_in_polygon. 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) Given a point and a polygon, check...

christopher/rosetta-code

http://rosettacode.org/wiki/List_comprehensions

List comprehensions

A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name. Some attributes of a list comprehension are: They should be distinct from (nested) for loops and the use of map and filter functio...

#JavaScript

JavaScript

// USING A LIST MONAD DIRECTLY, WITHOUT SPECIAL SYNTAX FOR LIST COMPREHENSIONS (function (n) { return mb(r(1, n), function (x) { // x <- [1..n] return mb(r(1 + x, n), function (y) { // y <- [1+x..n] return mb(r(1 + y, n), function (z) { // z <- [1+y..n] return x * x + y * y === z * z ? [...

Give a code snippet in #JavaScript A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name. Some attributes of a list comprehension are: They should be distinct from (nested) for loops a...

christopher/rosetta-code

http://rosettacode.org/wiki/Mertens_function

Mertens function

The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number. It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möbius numbers from n == 1 through n...

#Nim

Nim

import sequtils, strformat func mertensNumbers(max: int): seq[int] = result = repeat(1, max + 1) for n in 2..max: for k in 2..n: dec result[n], result[n div k] const Max = 1000 let mertens = mertensNumbers(Max) echo "First 199 Mertens numbers:" const Count = 200 var column = 0 for i in 0..<Count: ...

Give a code snippet in #Nim The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number. It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möbius ...

christopher/rosetta-code

http://rosettacode.org/wiki/Multi-dimensional_array

Multi-dimensional array

For the purposes of this task, the actual memory layout or access method of this data structure is not mandated. It is enough to: State the number and extent of each index to the array. Provide specific, ordered, integer indices for all dimensions of the array together with a new value to update the indexed value. ...

#Racket

Racket

# Raku supports multi dimension arrays natively. There are no arbitrary limits on the number of dimensions or maximum indices. Theoretically, you could have an infinite number of dimensions of infinite length, though in practice more than a few dozen dimensions gets unwieldy. An infinite maximum index is a fairly commo...

Give a code snippet in #Racket For the purposes of this task, the actual memory layout or access method of this data structure is not mandated. It is enough to: State the number and extent of each index to the array. Provide specific, ordered, integer indices for all dimensions of the array together with a new val...

christopher/rosetta-code

http://rosettacode.org/wiki/Empty_program

Empty program

Task Create the simplest possible program that is still considered "correct."

#DCL

DCL

{}

Give a code snippet in #DCL Task Create the simplest possible program that is still considered "correct."

christopher/rosetta-code

http://rosettacode.org/wiki/Loops/Infinite

Loops/Infinite

Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within l...

#ReScript

ReScript

while true { Js.log("SPAM") }

Give a code snippet in #ReScript Task Print out SPAM followed by a newline in an infinite loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach L...

christopher/rosetta-code

http://rosettacode.org/wiki/A%2BB

A+B

A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used. Task Given two integers, A and B. Their sum needs to be calculated. Input data Two integers are written in the input stream, separated by space(s): ( − 1000 ≤...

#SPAD

SPAD

(1) -> integer READ()$Lisp + integer READ()$Lisp 333 444 (1) 777 Type: PositiveInteger

Give a code snippet in #SPAD A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used. Task Given two integers, A and B. Their sum needs to be calculated. Input data Two integers are written in the input stream, separated...

christopher/rosetta-code

http://rosettacode.org/wiki/Pseudo-random_numbers/Combined_recursive_generator_MRG32k3a

Pseudo-random numbers/Combined recursive generator MRG32k3a

MRG32k3a Combined recursive generator (pseudo-code) /* Constants */ /* First generator */ a1 = [0, 1403580, -810728] m1 = 2**32 - 209 /* Second Generator */ a2 = [527612, 0, -1370589] m2 = 2**32 - 22853 d = m1 + 1 class MRG32k3a x1 = [0, 0, 0] /* list of three last values of...

#C

C

#include <math.h> #include <stdio.h> #include <stdint.h> int64_t mod(int64_t x, int64_t y) { int64_t m = x % y; if (m < 0) { if (y < 0) { return m - y; } else { return m + y; } } return m; } // Constants // First generator const static int64_t a1[3] = ...

Give a code snippet in #C MRG32k3a Combined recursive generator (pseudo-code) /* Constants */ /* First generator */ a1 = [0, 1403580, -810728] m1 = 2**32 - 209 /* Second Generator */ a2 = [527612, 0, -1370589] m2 = 2**32 - 22853 d = m1 + 1 class MRG32k3a x1 = [0, 0, 0] /* l...

christopher/rosetta-code

http://rosettacode.org/wiki/Search_a_list

Search a list

Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...

#Ring

Ring

haystack = ["alpha","bravo","charlie","delta","echo","foxtrot","golf", "hotel","india","juliet","kilo","lima","mike","needle", "november","oscar","papa","quebec","romeo","sierra","tango", "needle","uniform","victor","whisky","x-ray","yankee","zulu"] needle = "needle" maxindex = len(haystack) for index = 1 to ...

Give a code snippet in #Ring Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle tha...

christopher/rosetta-code

http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort

Sorting algorithms/Cocktail sort

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#PL.2FI

PL/I

cocktail: procedure (A); declare A(*) fixed; declare t fixed; declare stable bit (1); declare (i, n) fixed binary (31); n = hbound(A,1); do until (stable); stable = '1'b; do i = 1 to n-1, n-1 to 1 by -1; if A(i) > A(i+1) then do; stable = '0'b; /* still unsorted, so ...

Give a code snippet in #PL.2FI Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick s...

christopher/rosetta-code

http://rosettacode.org/wiki/Loops/Downward_for

Loops/Downward for

Task Write a for loop which writes a countdown from 10 to 0. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Increment loop index within loop body...

#Euphoria

Euphoria

for i = 10 to 0 by -1 do ? i end for

Give a code snippet in #Euphoria Task Write a for loop which writes a countdown from 10 to 0. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for Loops/For Loops/For with a specified step Loops/Foreach Loops/Inc...

christopher/rosetta-code

http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort

Sorting algorithms/Merge sort

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#CoffeeScript

CoffeeScript

# This is a simple version of mergesort that returns brand-new arrays. # A more sophisticated version would do more in-place optimizations. merge_sort = (arr) -> if arr.length <= 1 return (elem for elem in arr) m = Math.floor(arr.length / 2) arr1 = merge_sort(arr.slice 0, m) arr2 = merge_sort(arr.slice m) ...

Give a code snippet in #CoffeeScript Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Q...

christopher/rosetta-code

http://rosettacode.org/wiki/User_input/Text

User input/Text

User input/Text is part of Short Circuit's Console Program Basics selection. Task Input a string and the integer 75000 from the text console. See also: User input/Graphical

#D.C3.A9j.C3.A0_Vu

Déjà Vu

input s: !print\ s !decode!utf-8 !read-line!stdin local :astring input "Enter a string: " true while: try: to-num input "Enter the number 75000: " /= 75000 catch value-error: true

Give a code snippet in #D.C3.A9j.C3.A0_Vu User input/Text is part of Short Circuit's Console Program Basics selection. Task Input a string and the integer 75000 from the text console. See also: User input/Graphical

christopher/rosetta-code

http://rosettacode.org/wiki/Search_a_list

Search a list

Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that has multiple occurrences in ...

#zkl

zkl

L("Krusty","Charlie","Bozo","Bozo").index("Charlie") //--> 1 L("Krusty","Charlie","Bozo","Bozo").index("fred") //--> throws index error

Give a code snippet in #zkl Task[edit] Find the index of a string (needle) in an indexable, ordered collection of strings (haystack). Raise an exception if the needle is missing. If there is more than one occurrence then return the smallest index to the needle. Extra credit Return the largest index to a needle that...

christopher/rosetta-code

http://rosettacode.org/wiki/Loops/Foreach

Loops/Foreach

Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Loops/Do-while Loops/Downward for...

#ALGOL_68

ALGOL 68

[]UNION(STRING, INT, PROC(REF FILE)VOID) collection = ("Mary","Had",1,"little","lamb.",new line); FOR index FROM LWB collection TO UPB collection DO print((collection[index]," ")) OD

Give a code snippet in #ALGOL_68 Loop through and print each element in a collection in order. Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop. Related tasks Loop over multiple arrays simultaneously Loops/Break Loops/Continue Lo...

christopher/rosetta-code

http://rosettacode.org/wiki/Ordered_words

Ordered words

An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally assume that you have download...

#Io

Io

file := File clone openForReading("./unixdict.txt") words := file readLines file close maxLen := 0 orderedWords := list() words foreach(word, if( (word size >= maxLen) and (word == (word asMutable sort)), if( word size > maxLen, maxLen = word size orderedWords empty ) ...

Give a code snippet in #Io An ordered word is a word in which the letters appear in alphabetic order. Examples include abbey and dirt. Task[edit] Find and display all the ordered words in the dictionary unixdict.txt that have the longest word length. (Examples that access the dictionary file locally a...

christopher/rosetta-code

http://rosettacode.org/wiki/Thue-Morse

Thue-Morse

Task Create a Thue-Morse sequence. See also YouTube entry: The Fairest Sharing Sequence Ever YouTube entry: Math and OCD - My story with the Thue-Morse sequence Task: Fairshare between two and more

#Factor

Factor

USING: io kernel math math.parser sequences ; : thue-morse ( seq n -- seq' ) [ [ ] [ [ 1 bitxor ] map ] bi append ] times ; : print-tm ( seq -- ) [ number>string ] map "" join print ; 7 <iota> [ { 0 } swap thue-morse print-tm ] each

Give a code snippet in #Factor Task Create a Thue-Morse sequence. See also YouTube entry: The Fairest Sharing Sequence Ever YouTube entry: Math and OCD - My story with the Thue-Morse sequence Task: Fairshare between two and more

christopher/rosetta-code

http://rosettacode.org/wiki/Bulls_and_cows

Bulls and cows

Bulls and Cows Task Create a four digit random number from the digits 1 to 9, without duplication. The program should: ask for guesses to this number reject guesses that are malformed print the score for the guess The score is computed as: The player wins if the guess is the same as the random...

#Icon_and_Unicon

Icon and Unicon

procedure main() digits := "123456789" every !digits :=: ?digits num := digits[1+:4] repeat if score(num, getGuess(num)) then break write("Good job.") end procedure getGuess(num) repeat { writes("Enter a guess: ") guess := read() | stop("Quitter!") if *(guess ** '123456...

Give a code snippet in #Icon_and_Unicon Bulls and Cows Task Create a four digit random number from the digits 1 to 9, without duplication. The program should: ask for guesses to this number reject guesses that are malformed print the score for the guess The score is computed as: The player wi...

christopher/rosetta-code

http://rosettacode.org/wiki/Singly-linked_list/Element_insertion

Singly-linked list/Element insertion

Singly-Linked List (element) singly-linked list Using this method, insert an element C into a list comprised of elements A->B, following element A. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Trav...

#Kotlin

Kotlin

// version 1.1.2 class Node<T: Number>(var data: T, var next: Node<T>? = null) { override fun toString(): String { val sb = StringBuilder(this.data.toString()) var node = this.next while (node != null) { sb.append(" -> ", node.data.toString()) node = node.next ...

Give a code snippet in #Kotlin Singly-Linked List (element) singly-linked list Using this method, insert an element C into a list comprised of elements A->B, following element A. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definiti...

christopher/rosetta-code

http://rosettacode.org/wiki/Date_format

Date format

This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the current date in the formats of: 2007-11-23 and Friday, November 23, 2007

#NewLISP

NewLISP

; file: date-format.lsp ; url: http://rosettacode.org/wiki/Date_format ; author: oofoe 2012-02-01 ; The "now" function returns the current time as a list. A time zone ; offset in minutes can be supplied. The example below is for Eastern ; Standard Time. NewLISP's implicit list indexing is used to extract ; the f...

Give a code snippet in #NewLISP This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Task Display the current date in the formats of: 2007-11-23 and Friday, November 23, 2007

christopher/rosetta-code

http://rosettacode.org/wiki/Determine_if_only_one_instance_is_running

Determine if only one instance is running

This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.

#Oz

Oz

functor import Application Open System define fun {IsAlreadyRunning} try S = {New Open.socket init} in {S bind(takePort:12345)} false catch system(os(os "bind" ...) ...) then true end end if {IsAlreadyRunning} then {System.showInfo "Exiting because already running."} ...

Give a code snippet in #Oz This task is to determine if there is only one instance of an application running. If the program discovers that an instance of it is already running, then it should display a message indicating that it is already running and exit.

christopher/rosetta-code

http://rosettacode.org/wiki/Dining_philosophers

Dining philosophers

The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra. Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou...

#PicoLisp

PicoLisp

(de dining (Name State) (loop (prinl Name ": " State) (state 'State # Dispatch according to state (thinking 'hungry) # If thinking, get hungry (hungry # If hungry, grab random fork (if (rand T) (and ...

Give a code snippet in #PicoLisp The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra. Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and e...

christopher/rosetta-code

http://rosettacode.org/wiki/Sort_an_integer_array

Sort an integer array

Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...

#ALGOL_68

ALGOL 68

CO PR READ "shell_sort.a68" PR CO MODE TYPE = INT; PROC in place shell sort = (REF[]TYPE seq)REF[]TYPE:( INT inc := ( UPB seq + LWB seq + 1 ) OVER 2; WHILE inc NE 0 DO FOR index FROM LWB seq TO UPB seq DO INT i := index; TYPE el = seq[i]; WHILE ( i - LWB seq >= inc...

Give a code snippet in #ALGOL_68 Sorting Algorithm This is a sorting algorithm. It may be applied to a set of data in order to sort it. For comparing various sorts, see compare sorts. For other sorting algorithms, see sorting algorithms, or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick...

christopher/rosetta-code

http://rosettacode.org/wiki/Semiprime

Semiprime

Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes are also known as: semi-primes biprimes bi-primes 2-almost primes or simply: P2 Example 1679 = 23 × 73 (This particular number was chosen as the length of the Arecib...

#Erlang

Erlang

-module(factors). -export([factors/1,kthfactor/2]). factors(N) -> factors(N,2,[]). factors(1,_,Acc) -> Acc; factors(N,K,Acc) when N rem K == 0 -> factors(N div K,K, [K|Acc]); factors(N,K,Acc) -> factors(N,K+1,Acc). % is integer N factorable into M primes? kthfactor(N,M) -> case l...

Give a code snippet in #Erlang Semiprime numbers are natural numbers that are products of exactly two (possibly equal) prime numbers. Semiprimes are also known as: semi-primes biprimes bi-primes 2-almost primes or simply: P2 Example 1679 = 23 × 73 (This particular number was ch...

christopher/rosetta-code

http://rosettacode.org/wiki/Increment_a_numerical_string

Increment a numerical string

Task Increment a numerical string.

#ML

ML

ntos ` ston "1234" + 1;

Give a code snippet in #ML Task Increment a numerical string.

christopher/rosetta-code

http://rosettacode.org/wiki/Forest_fire

Forest fire

This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and Schwabl definition of the fores...

#Ada

Ada

with Ada.Numerics.Float_Random; use Ada.Numerics.Float_Random; with Ada.Text_IO; use Ada.Text_IO; procedure Forest_Fire is type Cell is (Empty, Tree, Fire); type Board is array (Positive range <>, Positive range <>) of Cell; procedure Step (S : in out Board; P, F : Float; Dice : Generator) is...

Give a code snippet in #Ada This page uses content from Wikipedia. The original article was at Forest-fire model. 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) Task Implement the Drossel and Sc...

christopher/rosetta-code

http://rosettacode.org/wiki/Rosetta_Code/Rank_languages_by_popularity

Rosetta Code/Rank languages by popularity

Rosetta Code/Rank languages by popularity You are encouraged to solve this task according to the task description, using any language you may know. Task Sort the most popular computer programming languages based in number of members in Rosetta Code categories. Sample output on 01 juin 2022 at 14:13 +02 Rank: 1 (1,...

#Oz

Oz

declare [HTTPClient] = {Module.link ['x-ozlib://mesaros/net/HTTPClient.ozf']} [Regex] = {Module.link ['x-oz://contrib/regex']} fun {GetPage RawUrl} Client = {New HTTPClient.urlGET init(inPrms(toFile:false toStrm:true) _)} Url = {VirtualString.toString RawUrl} OutParams HttpResponseParams i...

Give a code snippet in #Oz Rosetta Code/Rank languages by popularity You are encouraged to solve this task according to the task description, using any language you may know. Task Sort the most popular computer programming languages based in number of members in Rosetta Code categories. Sample output on 01 juin 202...

christopher/rosetta-code

http://rosettacode.org/wiki/Almost_prime

Almost prime

A k-Almost-prime is a natural number n {\displaystyle n} that is the product of k {\displaystyle k} (possibly identical) primes. Example 1-almost-primes, where k = 1 {\displaystyle k=1} , are the prime numbers themselves. 2-almost-primes, where k = 2 {\displaystyl...

#Raku

Raku

sub is-k-almost-prime($n is copy, $k) returns Bool { loop (my ($p, $f) = 2, 0; $f < $k && $p*$p <= $n; $p++) { $n /= $p, $f++ while $n %% $p; } $f + ($n > 1) == $k; } for 1 .. 5 -> $k { say ~.[^10] given grep { is-k-almost-prime($_, $k) }, 2 .. * }

Give a code snippet in #Raku A k-Almost-prime is a natural number n {\displaystyle n} that is the product of k {\displaystyle k} (possibly identical) primes. Example 1-almost-primes, where k = 1 {\displaystyle k=1} , are the prime numbers themselves. 2-almost-primes, whe...

christopher/rosetta-code

http://rosettacode.org/wiki/Video_display_modes

Video display modes

The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.

#BBC_BASIC

BBC BASIC

10 MODE 1: REM 320x256 4 colour graphics

Give a code snippet in #BBC_BASIC The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.

christopher/rosetta-code

http://rosettacode.org/wiki/Sequence:_smallest_number_greater_than_previous_term_with_exactly_n_divisors

Sequence: smallest number greater than previous term with exactly n divisors

Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors. Task Show here, on this page, at least the first 15 terms of the sequence. See also OEIS:A069654 Related tasks Sequence: smallest number with exactly n divisors Sequence: nth ...

#Factor

Factor

USING: io kernel math math.primes.factors prettyprint sequences ; : next ( n num -- n' num' ) [ 2dup divisors length = ] [ 1 + ] do until [ 1 + ] dip ; : A069654 ( n -- seq ) [ 2 1 ] dip [ [ next ] keep ] replicate 2nip ; "The first 15 terms of the sequence are:" print 15 A069654 .

Give a code snippet in #Factor Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors. Task Show here, on this page, at least the first 15 terms of the sequence. See also OEIS:A069654 Related tasks Sequence: smallest number with ex...

christopher/rosetta-code

http://rosettacode.org/wiki/Anti-primes

Anti-primes

The anti-primes (or highly composite numbers, sequence A002182 in the OEIS) are the natural numbers with more factors than any smaller than itself. Task Generate and show here, the first twenty anti-primes. Related tasks Factors of an integer Sieve of Eratosthenes

#Fortran

Fortran

program anti_primes use iso_fortran_env, only: output_unit implicit none integer :: n, d, maxDiv, pCount write(output_unit,*) "The first 20 anti-primes are:" n = 1 maxDiv = 0 pCount = 0 do if (pCount >= 20) exit d = countDivisors(n) if (d > maxDiv) then ...

Give a code snippet in #Fortran The anti-primes (or highly composite numbers, sequence A002182 in the OEIS) are the natural numbers with more factors than any smaller than itself. Task Generate and show here, the first twenty anti-primes. Related tasks Factors of an integer Sieve of Eratosthenes

christopher/rosetta-code

http://rosettacode.org/wiki/Magic_squares_of_singly_even_order

Magic squares of singly even order

A magic square is an NxN square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant). A magic square of singly even order has a size that is a multiple of 4, plus 2 (e.g. 6,...

#zkl

zkl

class MagicSquareSinglyEven{ fcn init(n){ var result=magicSquareSinglyEven(n) } fcn toString{ sink,n:=Sink(String),result.len(); // num collumns fmt:="%2s "; foreach row in (result) { sink.write(row.apply('wrap(n){ fmt.fmt(n) }).concat(),"\n") } sink.write("\nMagic constant: %d"....

Give a code snippet in #zkl A magic square is an NxN square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant). A magic square of singly even order has a size that is a m...

christopher/rosetta-code

http://rosettacode.org/wiki/Write_entire_file

Write entire file

Task (Over)write a file so that it contains a string. The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.

#Julia

Julia

function writeFile(filename, data) f = open(filename, "w") write(f, data) close(f) end writeFile("test.txt", "Hi there.")

Give a code snippet in #Julia Task (Over)write a file so that it contains a string. The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.

christopher/rosetta-code

http://rosettacode.org/wiki/Pointers_and_references

Pointers and references

Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...

#ARM_Assembly

ARM Assembly

;this example uses VASM syntax, your assembler may not use the # before constants or the semicolon for comments MOV R1,#0x04000000 MOV R0,#0x403 STR R0,[R1] ;store 0x403 into memory address 0x04000000.

Give a code snippet in #ARM_Assembly Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Oper...

christopher/rosetta-code

http://rosettacode.org/wiki/Detect_division_by_zero

Detect division by zero

Task Write a function to detect a divide by zero error without checking if the denominator is zero.

#RPGIV

RPGIV

dcl-c DIVIDE_BY_ZERO 00102; dcl-s result zoned(5:2); dcl-s value1 zoned(5:2); dcl-s value2 zoned(5:2); value1 = 10; value2 = 0; monitor; eval(h) result = value1 / value2; // Using half rounding here for the eval result on-error DIVIDE_BY_ZERO; ...

Give a code snippet in #RPGIV Task Write a function to detect a divide by zero error without checking if the denominator is zero.

christopher/rosetta-code

http://rosettacode.org/wiki/The_ISAAC_Cipher

The ISAAC Cipher

ISAAC is a cryptographically secure pseudo-random number generator (CSPRNG) and stream cipher. It was developed by Bob Jenkins from 1993 (http://burtleburtle.net/bob/rand/isaac.html) and placed in the Public Domain. ISAAC is fast - especially when optimised - and portable to most architectures in nearly all programming...

#Tcl

Tcl

package require Tcl 8.6 oo::class create ISAAC { variable aa bb cc mm randrsl randcnt constructor {seed} { namespace eval tcl { namespace eval mathfunc { proc mm {idx} { upvar 1 mm list lindex $list [expr {$idx % [llength $list]}] } proc clamp {value} { expr {$value & 0xFFFFFFF...

Give a code snippet in #Tcl ISAAC is a cryptographically secure pseudo-random number generator (CSPRNG) and stream cipher. It was developed by Bob Jenkins from 1993 (http://burtleburtle.net/bob/rand/isaac.html) and placed in the Public Domain. ISAAC is fast - especially when optimised - and portable to most architectu...

christopher/rosetta-code

http://rosettacode.org/wiki/Fibonacci_sequence

Fibonacci sequence

The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ...

#Corescript

Corescript

print Fibonacci Sequence: var previous = 1 var number = 0 var temp = (blank) :fib if number > 50000000000:kill print (number) set temp = (add number previous) set previous = (number) set number = (temp) goto fib :kill stop

Give a code snippet in #Corescript The Fibonacci sequence is a sequence Fn of natural numbers defined recursively: F0 = 0 F1 = 1 Fn = Fn-1 + Fn-2, if n>1 Task Write a function to generate the nth Fibonacci number. Solutions can be iterative or recursive (though recursive solution...

christopher/rosetta-code

http://rosettacode.org/wiki/Longest_increasing_subsequence

Longest increasing subsequence

Calculate and show here a longest increasing subsequence of the list: { 3 , 2 , 6 , 4 , 5 , 1 } {\displaystyle \{3,2,6,4,5,1\}} And of the list: { 0 , 8 , 4 , 12 , 2 , 10 , 6 , 14 , 1 , 9 , 5 , 13 , 3 , 11 , 7 , 15 } {\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}} Note that a list may have m...

#Ruby

Ruby

Node = Struct.new(:val, :back) def lis(n) pileTops = [] # sort into piles for x in n # binary search low, high = 0, pileTops.size-1 while low <= high mid = low + (high - low) / 2 if pileTops[mid].val >= x high = mid - 1 else low = mid + 1 end end i = l...

Give a code snippet in #Ruby Calculate and show here a longest increasing subsequence of the list: { 3 , 2 , 6 , 4 , 5 , 1 } {\displaystyle \{3,2,6,4,5,1\}} And of the list: { 0 , 8 , 4 , 12 , 2 , 10 , 6 , 14 , 1 , 9 , 5 , 13 , 3 , 11 , 7 , 15 } {\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}}...

christopher/rosetta-code

http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive

Verify distribution uniformity/Naive

This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...

#JavaScript

JavaScript

function distcheck(random_func, times, opts) { if (opts === undefined) opts = {} opts['delta'] = opts['delta'] || 2; var count = {}, vals = []; for (var i = 0; i < times; i++) { var val = random_func(); if (! has_property(count, val)) { count[val] = 1; vals.push...

Give a code snippet in #JavaScript This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing ra...

christopher/rosetta-code

http://rosettacode.org/wiki/Bitmap/Read_an_image_through_a_pipe

Bitmap/Read an image through a pipe

This task is the opposite of the PPM conversion through a pipe. In this task, using a delegate tool (like cjpeg, one of the netpbm package, or convert of the ImageMagick package) we read an image file and load it into the data storage type defined here. We can also use the code from Read ppm file, so that we can use PP...

#OCaml

OCaml

let read_image ~filename = if not(Sys.file_exists filename) then failwith(Printf.sprintf "the file %s does not exist" filename); let cmd = Printf.sprintf "convert \"%s\" ppm:-" filename in let ic, oc = Unix.open_process cmd in let img = read_ppm ~ic in (img) ;;

Give a code snippet in #OCaml This task is the opposite of the PPM conversion through a pipe. In this task, using a delegate tool (like cjpeg, one of the netpbm package, or convert of the ImageMagick package) we read an image file and load it into the data storage type defined here. We can also use the code from Read ...

christopher/rosetta-code

http://rosettacode.org/wiki/Modular_exponentiation

Modular exponentiation

Find the last 40 decimal digits of a b {\displaystyle a^{b}} , where a = 2988348162058574136915891421498819466320163312926952423791023078876139 {\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139} b = 235139930337346448646612254452369009474497523...

#Scheme

Scheme

(define (square n) (* n n)) (define (mod-exp a n mod) (cond ((= n 0) 1) ((even? n) (remainder (square (mod-exp a (/ n 2) mod)) mod)) (else (remainder (* a (mod-exp a (- n 1) mod)) mod)))) (define result (mod-exp 29883481620585741369158...

Give a code snippet in #Scheme Find the last 40 decimal digits of a b {\displaystyle a^{b}} , where a = 2988348162058574136915891421498819466320163312926952423791023078876139 {\displaystyle a=2988348162058574136915891421498819466320163312926952423791023078876139} b = 2351399303373...

christopher/rosetta-code

http://rosettacode.org/wiki/Boolean_values

Boolean values

Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks Logical operations

#Z80_Assembly

Z80 Assembly

BIT 0,A jr nz,true ;;;;;;;;;;;;;;;; AND 1 jr nz,true ;;;;;;;;;;;;;;;; RRCA jr c,true

Give a code snippet in #Z80_Assembly Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks Logical operations

christopher/rosetta-code