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http://rosettacode.org/wiki/Terminal_control/Ringing_the_terminal_bell
Terminal control/Ringing the terminal bell
Task Make the terminal running the program ring its "bell". On modern terminal emulators, this may be done by playing some other sound which might or might not be configurable, or by flashing the title bar or inverting the colors of the screen, but was classically a physical bell within the terminal.   It is usua...
#Action.21
Action!
PROC Wait(BYTE frames) BYTE RTCLOK=$14 frames==+RTCLOK WHILE frames#RTCLOK DO OD RETURN   PROC Main() BYTE i,n=[3], CH=$02FC ;Internal hardware value for last key pressed   PrintF("Press any key to hear %B bells...",n) DO UNTIL CH#$FF OD CH=$FF   FOR i=1 TO n DO Put(253) ;buzzer Wait(2...
Give a code snippet in #Action.21 Task Make the terminal running the program ring its "bell". On modern terminal emulators, this may be done by playing some other sound which might or might not be configurable, or by flashing the title bar or inverting the colors of the screen, but was classically a physical bel...
christopher/rosetta-code
http://rosettacode.org/wiki/Scope/Function_names_and_labels
Scope/Function names and labels
Task Explain or demonstrate the levels of visibility of function names and labels within the language. See also Variables for levels of scope relating to visibility of program variables Scope modifiers for general scope modification facilities
#Perl
Perl
no warnings 'redefine';   sub logger { print shift . ": Dicitur clamantis in deserto." }; # discarded   logger('A'); # can use before defined HighLander::logger('B'); # ditto, but referring to another package   package HighL...
Give a code snippet in #Perl Task Explain or demonstrate the levels of visibility of function names and labels within the language. See also Variables for levels of scope relating to visibility of program variables Scope modifiers for general scope modification facilities
christopher/rosetta-code
http://rosettacode.org/wiki/Day_of_the_week
Day of the week
A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between 2008 and 2121 will the 25th of ...
#Frink
Frink
for y = 2008 to 2121 if (parseDate["$y-12-25"] -> ### u ###) == "7" println[y]
Give a code snippet in #Frink A company decides that whenever Xmas falls on a Sunday they will give their workers all extra paid holidays so that, together with any public holidays, workers will not have to work the following week (between the 25th of December and the first of January). Task In what years between ...
christopher/rosetta-code
http://rosettacode.org/wiki/Create_a_file_on_magnetic_tape
Create a file on magnetic tape
The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
#C
C
  #include<stdio.h>   int main() { FILE* fp = fopen("TAPE.FILE","w");   fprintf(fp,"This code should be able to write a file to magnetic tape.\n"); fprintf(fp,"The Wikipedia page on Magnetic tape data storage shows that magnetic tapes are still in use.\n"); fprintf(fp,"In fact, the latest format, at the time of wri...
Give a code snippet in #C The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
christopher/rosetta-code
http://rosettacode.org/wiki/Loops/Nested
Loops/Nested
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over [ 1 , … , 20 ] {\displaystyle [1,\ldots ,20]} . The loops iterate rows and columns of the array printing the elements until the value 20 {\displaystyle 20} is met. Specifically, this task als...
#ColdFusion
ColdFusion
  <Cfset RandNum = 0> <Cfloop condition="randNum neq 20"> <Cfloop from="1" to="5" index="i"> <Cfset randNum = RandRange(1, 20)> <Cfoutput>#randNum# </Cfoutput> <Cfif RandNum eq 20><cfbreak></Cfif> </Cfloop> <br> </Cfloop>  
Give a code snippet in #ColdFusion Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over [ 1 , … , 20 ] {\displaystyle [1,\ldots ,20]} . The loops iterate rows and columns of the array printing the elements until the value 20 {\displaystyle 20} ...
christopher/rosetta-code
http://rosettacode.org/wiki/Terminal_control/Display_an_extended_character
Terminal control/Display an extended character
Task Display an extended (non ASCII) character onto the terminal. Specifically, display a   £   (GBP currency sign).
#Phix
Phix
puts(1,"£")
Give a code snippet in #Phix Task Display an extended (non ASCII) character onto the terminal. Specifically, display a   £   (GBP currency sign).
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
#XPath
XPath
'Goodbye, World!'
Give a code snippet in #XPath 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/Stand...
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 ≤...
#Arc
Arc
  (prn (+ (read) (read)))  
Give a code snippet in #Arc 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/Averages/Mode
Averages/Mode
Task[edit] Write a program to find the mode value of a collection. The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique. If it is not appropriate or possible to support a general collection, use a vector (array), if possible. If it is not appropriat...
#K
K
mode: {(?x)@&n=|/n:#:'=x} mode 1 1 1 1 2 2 2 3 3 3 3 4 4 3 2 4 4 4 3 4
Give a code snippet in #K Task[edit] Write a program to find the mode value of a collection. The case where the collection is empty may be ignored. Care must be taken to handle the case where the mode is non-unique. If it is not appropriate or possible to support a general collection, use a vector (array), if possib...
christopher/rosetta-code
http://rosettacode.org/wiki/Jensen%27s_Device
Jensen's Device
Jensen's Device You are encouraged to solve this task according to the task description, using any language you may know. This task is an exercise in call by name. Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Jensen after studying the ALGOL 60 Report. The following pr...
#Erlang
Erlang
  -module( jensens_device ).   -export( [task/0] ).   task() -> sum( 1, 100, fun (I) -> 1 / I end ).   sum( I, High, _Term ) when I > High -> 0; sum( I, High, Term ) -> Temp = Term( I ), Temp + sum( I + 1, High, Term ).  
Give a code snippet in #Erlang Jensen's Device You are encouraged to solve this task according to the task description, using any language you may know. This task is an exercise in call by name. Jensen's Device is a computer programming technique devised by Danish computer scientist Jørn Jensen after studying the AL...
christopher/rosetta-code
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included)
Arbitrary-precision integers (included)
Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
#MATLAB
MATLAB
>> answer = vpi(5)^(vpi(4)^(vpi(3)^vpi(2))); >> numDigits = order(answer) + 1   numDigits =   183231   >> [sprintf('%d',leadingdigit(answer,20)) '...' sprintf('%d',trailingdigit(answer,20))] %First and Last 20 Digits   ans =   62060698786608744707...92256259918212890625
Give a code snippet in #MATLAB Using the in-built capabilities of your language, calculate the integer value of: 5 4 3 2 ...
christopher/rosetta-code
http://rosettacode.org/wiki/Mandelbrot_set
Mandelbrot set
Mandelbrot set You are encouraged to solve this task according to the task description, using any language you may know. Task Generate and draw the Mandelbrot set. Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
#Common_Lisp
Common Lisp
(defpackage #:mandelbrot (:use #:cl))   (in-package #:mandelbrot)   (deftype pixel () '(unsigned-byte 8)) (deftype image () '(array pixel))   (defun write-pgm (image filespec) (declare (image image)) (with-open-file (s filespec :direction :output :element-type 'pixel :if-exists :supersede) (let* ((width (arr...
Give a code snippet in #Common_Lisp Mandelbrot set You are encouraged to solve this task according to the task description, using any language you may know. Task Generate and draw the Mandelbrot set. Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
christopher/rosetta-code
http://rosettacode.org/wiki/Program_termination
Program termination
Task Show the syntax for a complete stoppage of a program inside a   conditional. This includes all threads/processes which are part of your program. Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks...
#AWK
AWK
if(problem)exit 1
Give a code snippet in #AWK Task Show the syntax for a complete stoppage of a program inside a   conditional. This includes all threads/processes which are part of your program. Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/d...
christopher/rosetta-code
http://rosettacode.org/wiki/Untouchable_numbers
Untouchable numbers
Definitions   Untouchable numbers   are also known as   nonaliquot numbers.   An   untouchable number   is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer.   (From Wikipedia)   The   sum of all the proper divisors   is also known as   the   aliquot sum.   A...
#C.2B.2B
C++
  // Untouchable Numbers : Nigel Galloway - March 4th., 2021; #include <functional> #include <bitset> #include <iostream> #include <cmath> using namespace std; using Z0=long long; using Z1=optional<Z0>; using Z2=optional<array<int,3>>; using Z3=function<Z2()>; const int maxUT{3000000}, dL{(int)log2(maxUT)}; struct uT{...
Give a code snippet in #C.2B.2B Definitions   Untouchable numbers   are also known as   nonaliquot numbers.   An   untouchable number   is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer.   (From Wikipedia)   The   sum of all the proper divisors   is also k...
christopher/rosetta-code
http://rosettacode.org/wiki/One_of_n_lines_in_a_file
One of n lines in a file
A method of choosing a line randomly from a file: Without reading the file more than once When substantial parts of the file cannot be held in memory Without knowing how many lines are in the file Is to: keep the first line of the file as a possible choice, then Read the second line of the file if possible and m...
#Batch_File
Batch File
  @echo off   for /l %%i in (1,1,10000) do call one_of_n :: To show progress add to the FOR loop code block - :: title %%i   for /l %%i in (1,1,10) do ( for /f "usebackq tokens=1,2 delims=:" %%j in (`find /c "%%i" output.txt`) do echo Line %%i =%%k ) del output.txt pause>nul  
Give a code snippet in #Batch_File A method of choosing a line randomly from a file: Without reading the file more than once When substantial parts of the file cannot be held in memory Without knowing how many lines are in the file Is to: keep the first line of the file as a possible choice, then Read the secon...
christopher/rosetta-code
http://rosettacode.org/wiki/Recaman%27s_sequence
Recaman's sequence
The Recamán's sequence generates Natural numbers. Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated. If the conditions don't hold then a(n) = a(n-1) + n. Task Generate and show here the...
#Quackery
Quackery
  [ stack 0 ] is seennumbers ( --> s )   [ bit seennumbers take | seennumbers put ] is seen ( n --> )   [ dup 0 < iff [ drop true ] done bit seennumbers share & 0 != ] is seen? ( n --> b )   [ 1+ bit 1 - seennumbers share ov...
Give a code snippet in #Quackery The Recamán's sequence generates Natural numbers. Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated. If the conditions don't hold then a(n) = a(n-1) + n. ...
christopher/rosetta-code
http://rosettacode.org/wiki/N-queens_problem
N-queens problem
Solve the eight queens puzzle. You can extend the problem to solve the puzzle with a board of size   NxN. For the number of solutions for small values of   N,   see   OEIS: A000170. Related tasks A* search algorithm Solve a Hidato puzzle Solve a Holy Knight's tour Knight's tour Peaceful chess queen armie...
#PowerShell
PowerShell
  function PlaceQueen ( [ref]$Board, $Row, $N ) { # For the current row, start with the first column $Board.Value[$Row] = 0   # While haven't exhausted all columns in the current row... While ( $Board.Value[$Row] -lt $N ) { # If not the first row, check for conflicts $Conf...
Give a code snippet in #PowerShell Solve the eight queens puzzle. You can extend the problem to solve the puzzle with a board of size   NxN. For the number of solutions for small values of   N,   see   OEIS: A000170. Related tasks A* search algorithm Solve a Hidato puzzle Solve a Holy Knight's tour Knigh...
christopher/rosetta-code
http://rosettacode.org/wiki/Averages/Arithmetic_mean
Averages/Arithmetic mean
Task[edit] Write a program to find the mean (arithmetic average) of a numeric vector. In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin...
#zonnon
zonnon
  module Averages; type Vector = array {math} * of real;   procedure ArithmeticMean(x: Vector): real; begin (* sum is a predefined function for mathematical arrays *) return sum(x) end ArithmeticMean; var x: Vector;   begin x := new Vector(4); x := [1.0, 2.3, 3.2, 2.1, 5.3]; write("arithmetic mean: ");writ...
Give a code snippet in #zonnon Task[edit] Write a program to find the mean (arithmetic average) of a numeric vector. In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an est...
christopher/rosetta-code
http://rosettacode.org/wiki/SEDOLs
SEDOLs
Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852842 B0YBKT7 B000300 Extra credit ...
#VBScript
VBScript
  arr = Array("710889",_ "B0YBKJ",_ "406566",_ "B0YBLH",_ "228276",_ "B0YBKL",_ "557910",_ "B0YBKR",_ "585284",_ "B0YBKT",_ "12345",_ "A12345",_ "B00030")   For j = 0 To UBound(arr) WScript.StdOut.Write arr(j) & getSEDOLCheckDigit(arr(j)) WScri...
Give a code snippet in #VBScript Task For each number list of 6-digit SEDOLs, calculate and append the checksum digit. That is, given this input: 710889 B0YBKJ 406566 B0YBLH 228276 B0YBKL 557910 B0YBKR 585284 B0YBKT B00030 Produce this output: 7108899 B0YBKJ7 4065663 B0YBLH2 2282765 B0YBKL9 5579107 B0YBKR5 5852...
christopher/rosetta-code
http://rosettacode.org/wiki/Colour_pinstripe/Display
Colour pinstripe/Display
The task is to create 1 pixel wide coloured vertical pinstripes with a sufficient number of pinstripes to span the entire width of the graphics display. The pinstripes should either follow the system palette sequence,   or a sequence that includes: black,   red,   green,   blue,   magenta,   cyan,   yellow,   and  ...
#Wren
Wren
import "graphics" for Canvas, Color import "dome" for Window   class Game { static init() { Window.title = "Color pinstripe" __width = 900 __height = 600 Canvas.resize(__width, __height) Window.resize(__width, __height) var colors = [ Color.hex("000000"), ...
Give a code snippet in #Wren The task is to create 1 pixel wide coloured vertical pinstripes with a sufficient number of pinstripes to span the entire width of the graphics display. The pinstripes should either follow the system palette sequence,   or a sequence that includes: black,   red,   green,   blue,   mage...
christopher/rosetta-code
http://rosettacode.org/wiki/Literals/Integer
Literals/Integer
Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be interpreted by the compiler or...
#Forth
Forth
HEX FEEDFACE 2 BASE ! 1011001 DECIMAL 1234 : mask var @ [ base @ hex ] 3fff and [ base ! ] var ! ;
Give a code snippet in #Forth Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be...
christopher/rosetta-code
http://rosettacode.org/wiki/Flow-control_structures
Flow-control structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task Document common flow-control structures. One common example of a flow-control structure is the   goto   construct. Note that   Conditional Struc...
#Yabasic
Yabasic
  gosub subrutina   label bucle print "Bucle infinito" goto bucle end   label subrutina print "En subrutina" wait 10 return end  
Give a code snippet in #Yabasic Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task Document common flow-control structures. One common example of a flow-control structure is the   goto   construc...
christopher/rosetta-code
http://rosettacode.org/wiki/Taxicab_numbers
Taxicab numbers
A   taxicab number   (the definition that is being used here)   is a positive integer that can be expressed as the sum of two positive cubes in more than one way. The first taxicab number is   1729,   which is: 13   +   123       and also 93   +   103. Taxicab numbers are also known as:   taxi numbers   tax...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
findTaxi[n_] := Sort[Keys[Select[Counts[Flatten[Table[x^3 + y^3, {x, 1, n}, {y, x, n}]]], GreaterThan[1]]]]; Take[findTaxiNumbers[100], 25] found=findTaxiNumbers[1200][[2000 ;; 2005]] Map[Reduce[x^3 + y^3 == # && x >= y && x > 0 && y > 0, {x, y}, Integers] &, found]
Give a code snippet in #Mathematica.2FWolfram_Language A   taxicab number   (the definition that is being used here)   is a positive integer that can be expressed as the sum of two positive cubes in more than one way. The first taxicab number is   1729,   which is: 13   +   123       and also 93   +   103. Ta...
christopher/rosetta-code
http://rosettacode.org/wiki/Sum_of_a_series
Sum of a series
Compute the   nth   term of a series,   i.e. the sum of the   n   first terms of the corresponding sequence. Informally this value, or its limit when   n   tends to infinity, is also called the sum of the series, thus the title of this task. For this task, use: S n = ∑ k = 1 n 1 k 2 {\displa...
#OCaml
OCaml
let sum a b fn = let result = ref 0. in for i = a to b do result := !result +. fn i done; !result
Give a code snippet in #OCaml Compute the   nth   term of a series,   i.e. the sum of the   n   first terms of the corresponding sequence. Informally this value, or its limit when   n   tends to infinity, is also called the sum of the series, thus the title of this task. For this task, use: S n = ∑ k = 1...
christopher/rosetta-code
http://rosettacode.org/wiki/Comments
Comments
Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
#BQN
BQN
# This is a comment
Give a code snippet in #BQN Task Show all ways to include text in a language source file that's completely ignored by the compiler or interpreter. Related tasks   Documentation   Here_document See also   Wikipedia   xkcd (Humor: hand gesture denoting // for "commenting out" people.)
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...
#Tiny_BASIC
Tiny BASIC
  REM Almost prime LET K=1 10 IF K>5 THEN END PRINT "k = ",K,":" LET I=2 LET C=0 20 IF C>=10 THEN GOTO 40 LET N=I GOSUB 500 IF P=0 THEN GOTO 30 PRINT I LET C=C+1 30 LET I=I+1 GOTO 20 40 LET K=K+1 GOTO 10   REM Check if N is a K prime (result: P) 500 LET F=0 LE...
Give a code snippet in #Tiny_BASIC 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,...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort
Sorting algorithms/Insertion 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 ...
#EasyLang
EasyLang
subr sort for i = 1 to len data[] - 1 h = data[i] j = i - 1 while j >= 0 and h < data[j] data[j + 1] = data[j] j -= 1 . data[j + 1] = h . . data[] = [ 29 4 72 44 55 26 27 77 92 5 ] call sort print data[]
Give a code snippet in #EasyLang 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/Penney%27s_game
Penney's game
Penney's game is a game where two players bet on being the first to see a particular sequence of heads or tails in consecutive tosses of a fair coin. It is common to agree on a sequence length of three then one player will openly choose a sequence, for example: Heads, Tails, Heads, or HTH for short. The other pla...
#Ruby
Ruby
Toss = [:Heads, :Tails]   def yourChoice puts "Enter your choice (H/T)" choice = [] 3.times do until (c = $stdin.getc.upcase) == "H" or c == "T" end choice << (c=="H" ? Toss[0] : Toss[1]) end puts "You chose #{choice.join(' ')}" choice end   loop do puts "\n%s I start, %s you start ..... %s" %...
Give a code snippet in #Ruby Penney's game is a game where two players bet on being the first to see a particular sequence of heads or tails in consecutive tosses of a fair coin. It is common to agree on a sequence length of three then one player will openly choose a sequence, for example: Heads, Tails, Heads, or...
christopher/rosetta-code
http://rosettacode.org/wiki/Topological_sort
Topological sort
Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort ...
#Tailspin
Tailspin
  data node <'.+'>, from <node>, to <node>   templates topologicalSort @: []; {V: {|$.v..., $.e({node: §.to})...|} , E: {|$.e... -> \(<{from: <~=$.to>}> $! \)|}} -> # when <{V: <?($::count <=0>)>}> $@! otherwise def independent: ($.V notMatching $.E({node: §.from})); [$independent... -> $.node] -> ..|@:...
Give a code snippet in #Tailspin Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick...
christopher/rosetta-code
http://rosettacode.org/wiki/Exponentiation_operator
Exponentiation operator
Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or procedure) overloading, then an ov...
#Delphi
Delphi
  program Exponentiation_operator;   {$APPTYPE CONSOLE}   uses System.SysUtils;   type TDouble = record Value: Double; class operator Implicit(a: TDouble): Double; class operator Implicit(a: Double): TDouble; class operator Implicit(a: TDouble): string; class operator LogicalXor(a: TDouble; b: I...
Give a code snippet in #Delphi Most programming languages have a built-in implementation of exponentiation. Task Re-implement integer exponentiation for both   intint   and   floatint   as both a procedure,   and an operator (if your language supports operator definition). If the language supports operator (or pr...
christopher/rosetta-code
http://rosettacode.org/wiki/Run-length_encoding
Run-length encoding
Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression...
#Java
Java
import java.util.regex.Matcher; import java.util.regex.Pattern; public class RunLengthEncoding {   public static String encode(String source) { StringBuffer dest = new StringBuffer(); for (int i = 0; i < source.length(); i++) { int runLength = 1; while (i+1 < source.length() ...
Give a code snippet in #Java Run-length encoding You are encouraged to solve this task according to the task description, using any language you may know. Task Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a funct...
christopher/rosetta-code
http://rosettacode.org/wiki/Compile-time_calculation
Compile-time calculation
Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
#Prolog
Prolog
% Taken from RosettaCode Factorial page for Prolog fact(X, 1) :- X<2. fact(X, F) :- Y is X-1, fact(Y,Z), F is Z*X.   goal_expansion((X = factorial_of(N)), (X = F)) :- fact(N,F).   test :- F = factorial_of(10), format('!10 = ~p~n', F).
Give a code snippet in #Prolog Some programming languages allow calculation of values at compile time. Task Calculate   10!   (ten factorial)   at compile time. Print the result when the program is run. Discuss what limitations apply to compile-time calculations in your language.
christopher/rosetta-code
http://rosettacode.org/wiki/Literals/Integer
Literals/Integer
Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be interpreted by the compiler or...
#Ursa
Ursa
decl int i set i 123 set i -456
Give a code snippet in #Ursa Some programming languages have ways of expressing integer literals in bases other than the normal base ten. Task Show how integer literals can be expressed in as many bases as your language allows. Note:   this should not involve the calling of any functions/methods, but should be ...
christopher/rosetta-code
http://rosettacode.org/wiki/Rename_a_file
Rename a file
Task Rename:   a file called     input.txt     into     output.txt     and   a directory called     docs     into     mydocs. This should be done twice:   once "here", i.e. in the current working directory and once in the filesystem root. It can be assumed that the user has the rights to do so. (In unix-type s...
#Objeck
Objeck
  use IO; bundle Default { class FileExample { function : Main(args : String[]) ~ Nil { File->Rename("input.txt", "output.txt"); File->Rename("docs", "mydocs"); File->Rename("/input.txt", "/output.txt"); File->Rename("/docs", "/mydocs"); } } }  
Give a code snippet in #Objeck Task Rename:   a file called     input.txt     into     output.txt     and   a directory called     docs     into     mydocs. This should be done twice:   once "here", i.e. in the current working directory and once in the filesystem root. It can be assumed that the user has the r...
christopher/rosetta-code
http://rosettacode.org/wiki/Mayan_numerals
Mayan numerals
Task Present numbers using the Mayan numbering system   (displaying the Mayan numerals in a cartouche). Mayan numbers Normally, Mayan numbers are written vertically   (top─to─bottom)   with the most significant numeral at the top   (in the sense that decimal numbers are written left─to─right with the most signific...
#Nim
Nim
  import algorithm   type Border = enum UL = "╔", UC = "╦", UR = "╗", LL = "╚", LC = "╩", LR = "╝", HB = "═", VB = "║"   const   Mayan = [" ", " ∙ ", " ∙∙ ", "∙∙∙ ", "∙∙∙∙"]   M0 = " Θ " M5 = "────"   type Digit = range[0..19] Numeral = array[4, string] MayanNumber = seq[Numeral]     func toBase20(n: N...
Give a code snippet in #Nim Task Present numbers using the Mayan numbering system   (displaying the Mayan numerals in a cartouche). Mayan numbers Normally, Mayan numbers are written vertically   (top─to─bottom)   with the most significant numeral at the top   (in the sense that decimal numbers are written left─to...
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
#GUISS
GUISS
Start,Programs,Accessories,Notepad,Type:Goodbye World[pling]
Give a code snippet in #GUISS 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/Stand...
christopher/rosetta-code
http://rosettacode.org/wiki/AKS_test_for_primes
AKS test for primes
The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles. The theorem on which the test is based can be stated as follows:   a number   p {\displaystyle p}   is prime   if and only if   all the coefficients of the polynomial ...
#11l
11l
F expand_x_1(p) V ex = [BigInt(1)] L(i) 0 .< p ex.append(ex.last * -(p - i) I/ (i + 1)) R reversed(ex)   F aks_test(p) I p < 2 R 0B V ex = expand_x_1(p) ex[0]++ R !any(ex[0 .< (len)-1].map(mult -> mult % @p != 0))   print(‘# p: (x-1)^p for small p’) L(p) 12 print(‘#3: #.’.format(p, e...
Give a code snippet in #11l The AKS algorithm for testing whether a number is prime is a polynomial-time algorithm based on an elementary theorem about Pascal triangles. The theorem on which the test is based can be stated as follows:   a number   p {\displaystyle p}   is prime   if and only if   all the co...
christopher/rosetta-code
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#ERRE
ERRE
  PROGRAM VECTORPRODUCT   !$DOUBLE   TYPE TVECTOR=(X,Y,Z)   DIM A:TVECTOR,B:TVECTOR,C:TVECTOR   DIM AA:TVECTOR,BB:TVECTOR,CC:TVECTOR DIM DD:TVECTOR,EE:TVECTOR,FF:TVECTOR   PROCEDURE DOTPRODUCT(DD.,EE.->DOTP) DOTP=DD.X*EE.X+DD.Y*EE.Y+DD.Z*EE.Z END PROCEDURE   PROCEDURE CROSSPRODUCT(DD.,EE.->FF.) FF.X=DD.Y*EE.Z-DD....
Give a code snippet in #ERRE A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of num...
christopher/rosetta-code
http://rosettacode.org/wiki/ISBN13_check_digit
ISBN13 check digit
Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:   978-1734314502       (good)   ...
#UNIX_Shell
UNIX Shell
check_isbn13 () { local i n t n=${1//[^0-9]/} t=0 for ((i=0; i<${#n}; ++i )); do (( t += ${n:i:1}*(1 + ((i&1)<<1)) )) done (( 0 == t % 10 )) }   for isbn in 978-1734314502 978-1734314509 978-1788399081 978-1788399083; do printf '%s: ' "$isbn" if check_isbn13 "$isbn"; then printf '%...
Give a code snippet in #UNIX_Shell Task Validate the check digit of an ISBN-13 code:   Multiply every other digit by  3.   Add these numbers and the other digits.   Take the remainder of this number after division by  10.   If it is  0,   the ISBN-13 check digit is correct. Use the following codes for testing:...
christopher/rosetta-code
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Common_Lisp
Common Lisp
(defun visualize (tree) (labels ((rprint (list) (mapc #'princ (reverse list))) (vis-h (tree branches) (let ((len (length tree))) (loop for item in tree for idx from 1 to len do (cond ((listp item) ...
Give a code snippet in #Common_Lisp A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables  ...
christopher/rosetta-code
http://rosettacode.org/wiki/Sieve_of_Eratosthenes
Sieve of Eratosthenes
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   algorithm, with the only allowed...
#Ursala
Ursala
#import nat   sieve = ~<{0,1}&& iota; @NttPX ~&r->lx ^/~&rhPlC remainder@rlX~|@r
Give a code snippet in #Ursala This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer. Task Implement the   Sieve of Eratosthenes   ...
christopher/rosetta-code
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#Python
Python
from PIL import Image   # Open the image image = Image.open("lena.jpg") # Get the width and height of the image width, height = image.size # Calculate the amount of pixels amount = width * height   # Total amount of greyscale total = 0 # B/W image bw_image = Image.new('L', (width, height), 0) # Bitmap image bm_image = ...
Give a code snippet in #Python Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must h...
christopher/rosetta-code
http://rosettacode.org/wiki/Rename_a_file
Rename a file
Task Rename:   a file called     input.txt     into     output.txt     and   a directory called     docs     into     mydocs. This should be done twice:   once "here", i.e. in the current working directory and once in the filesystem root. It can be assumed that the user has the rights to do so. (In unix-type s...
#C
C
#include <stdio.h>   int main() { rename("input.txt", "output.txt"); rename("docs", "mydocs"); rename("/input.txt", "/output.txt"); rename("/docs", "/mydocs"); return 0; }
Give a code snippet in #C Task Rename:   a file called     input.txt     into     output.txt     and   a directory called     docs     into     mydocs. This should be done twice:   once "here", i.e. in the current working directory and once in the filesystem root. It can be assumed that the user has the rights...
christopher/rosetta-code
http://rosettacode.org/wiki/Singly-linked_list/Traversal
Singly-linked list/Traversal
Traverse from the beginning of a singly-linked list to the end. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked ...
#Haskell
Haskell
map (>5) [1..10] -- [False,False,False,False,False,True,True,True,True,True]   map (++ "s") ["Apple", "Orange", "Mango", "Pear"] -- ["Apples","Oranges","Mangos","Pears"]   foldr (+) 0 [1..10] -- prints 55   traverse :: [a] -> [a] traverse list = map func list where func a = -- ...do something with a
Give a code snippet in #Haskell Traverse from the beginning of a singly-linked list to the end. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Defin...
christopher/rosetta-code
http://rosettacode.org/wiki/Even_or_odd
Even or odd
Task Test whether an integer is even or odd. There is more than one way to solve this task: Use the even and odd predicates, if the language provides them. Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd. Divide i by 2. The remainder equals...
#AutoHotkey
AutoHotkey
if ( int & 1 ){ ; do odd stuff }else{ ; do even stuff }
Give a code snippet in #AutoHotkey Task Test whether an integer is even or odd. There is more than one way to solve this task: Use the even and odd predicates, if the language provides them. Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd. ...
christopher/rosetta-code
http://rosettacode.org/wiki/Yellowstone_sequence
Yellowstone sequence
The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is a permutation of the natural n...
#XPL0
XPL0
func GCD(N, D); \Return the greatest common divisor of N and D int N, D, R; \numerator, denominator, remainder [if D > N then [R:=D; D:=N; N:=R]; \swap D and N while D > 0 do [R:= rem(N/D); N:= D; D:= R; ]; return N; ];   int I, A(30+1), N, T; [for I:= 1 to 3 do A(I):= I; ...
Give a code snippet in #XPL0 The Yellowstone sequence, also called the Yellowstone permutation, is defined as: For n <= 3, a(n) = n For n >= 4, a(n) = the smallest number not already in sequence such that a(n) is relatively prime to a(n-1) and is not relatively prime to a(n-2). The sequence is ...
christopher/rosetta-code
http://rosettacode.org/wiki/Ackermann_function
Ackermann function
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree. The Ackermann function is usually defined as follows: A ( m , n ) = { n + 1 if  m = 0 A ( m ...
#C.2B.2B
C++
#include <iostream>   unsigned int ackermann(unsigned int m, unsigned int n) { if (m == 0) { return n + 1; } if (n == 0) { return ackermann(m - 1, 1); } return ackermann(m - 1, ackermann(m, n - 1)); }   int main() { for (unsigned int m = 0; m < 4; ++m) { for (unsigned int n = 0; n < 10; ++n) { ...
Give a code snippet in #C.2B.2B The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree. The Ackermann function is usually defined as follows: A ( m , n ) = { ...
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 |...
#11l
11l
print(‘abcd’.starts_with(‘ab’)) print(‘abcd’.ends_with(‘zn’)) print(‘bb’ C ‘abab’) print(‘ab’ C ‘abab’) print(‘abab’.find(‘bb’) ? -1) print(‘abab’.find(‘ab’) ? -1)
Give a code snippet in #11l 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 Co...
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 |...
#Emacs_Lisp
Emacs Lisp
(defun string-contains (needle haystack) (string-match (regexp-quote needle) haystack))   (string-prefix-p "before" "before center after") ;=> t (string-contains "before" "before center after") ;=> 0 (string-suffix-p "before" "before center after") ;=> nil   (string-prefix-p "center" "before center after") ;=> nil (s...
Give a code snippet in #Emacs_Lisp 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 Operat...
christopher/rosetta-code
http://rosettacode.org/wiki/FizzBuzz
FizzBuzz
Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz     (instead of the number) ...
#Dart
Dart
  main() { for (int i = 1; i <= 100; i++) { List<String> out = []; if (i % 3 == 0) out.add("Fizz"); if (i % 5 == 0) out.add("Buzz"); print(out.length > 0 ? out.join("") : i); } }  
Give a code snippet in #Dart Task Write a program that prints the integers from   1   to   100   (inclusive). But:   for multiples of three,   print   Fizz     (instead of the number)   for multiples of five,   print   Buzz     (instead of the number)   for multiples of both three and five,   print   FizzBuzz ...
christopher/rosetta-code
http://rosettacode.org/wiki/User_input/Graphical
User input/Graphical
In this task, the goal is to input a string and the integer 75000, from graphical user interface. See also: User input/Text
#BBC_BASIC
BBC BASIC
INSTALL @lib$+"WINLIB2" INSTALL @lib$+"WINLIB5" ES_NUMBER = 8192   form% = FN_newdialog("Rosetta Code", 100, 100, 100, 64, 8, 1000) PROC_static(form%, "String:", 100, 8, 8, 30, 14, 0) PROC_editbox(form%, "Example", 101, 40, 6, 52, 14, 0) PROC_static(form%, "Number:", 102, 8, 26...
Give a code snippet in #BBC_BASIC In this task, the goal is to input a string and the integer 75000, from graphical user interface. See also: User input/Text
christopher/rosetta-code
http://rosettacode.org/wiki/K-d_tree
K-d tree
This page uses content from Wikipedia. The original article was at K-d tree. 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) A k-d tree (short for k-dimensional tree) is a space-partitioning data str...
#Java
Java
import java.util.*;   public class KdTree { private int dimensions_; private Node root_ = null; private Node best_ = null; private double bestDistance_ = 0; private int visited_ = 0;   public KdTree(int dimensions, List<Node> nodes) { dimensions_ = dimensions; root_ = makeTree(no...
Give a code snippet in #Java This page uses content from Wikipedia. The original article was at K-d tree. 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) A k-d tree (short for k-dimensional tree) 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 ...
#min
min
( (2 <) ((0 1 (dup rollup +)) dip pred times nip) unless ) :fib
Give a code snippet in #min 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 g...
christopher/rosetta-code
http://rosettacode.org/wiki/Smarandache_prime-digital_sequence
Smarandache prime-digital sequence
The Smarandache prime-digital sequence (SPDS for brevity) is the sequence of primes whose digits are themselves prime. For example 257 is an element of this sequence because it is prime itself and its digits: 2, 5 and 7 are also prime. Task Show the first 25 SPDS primes. Show the hundredth SPDS prime. See also ...
#Wren
Wren
import "/math" for Int   var limit = 1000 var spds = List.filled(limit, 0) spds[0] = 2 var i = 3 var count = 1 while (count < limit) { if (Int.isPrime(i)) { var digits = i.toString if (digits.all { |d| "2357".contains(d) }) { spds[count] = i count = count + 1 } } ...
Give a code snippet in #Wren The Smarandache prime-digital sequence (SPDS for brevity) is the sequence of primes whose digits are themselves prime. For example 257 is an element of this sequence because it is prime itself and its digits: 2, 5 and 7 are also prime. Task Show the first 25 SPDS primes. Show the hundr...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort
Sorting algorithms/Insertion 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 ...
#360_Assembly
360 Assembly
* Insertion sort 16/06/2016 INSSORT CSECT USING INSSORT,R13 base register B 72(R15) skip savearea DC 17F'0' savearea STM R14,R12,12(R13) prolog ST R13,4(R15) " ST R15,8(R13) " ...
Give a code snippet in #360_Assembly 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/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. ...
#FOCAL
FOCAL
01.10 FOR I=1,4; DO 2.0   02.10 FOR J=1,I; TYPE "*" 02.20 TYPE !
Give a code snippet in #FOCAL “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 structu...
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
#Raku
Raku
my $str = prompt("Enter a string: "); my $int = prompt("Enter a integer: ");
Give a code snippet in #Raku 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/Fork
Fork
Task Spawn a new process which can run simultaneously with, and independently of, the original parent process.
#X86-64_Assembly
X86-64 Assembly
  option casemap:none   windows64 equ 1 linux64 equ 3   ifndef __THREAD_CLASS__ __THREAD_CLASS__ equ 1   if @Platform eq windows64 option dllimport:<kernel32> CreateThread proto :qword, :qword, :qword, :qword, :dword, :qword HeapAlloc proto :qword, :dword, :qword HeapFree...
Give a code snippet in #X86-64_Assembly Task Spawn a new process which can run simultaneously with, and independently of, the original parent process.
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Patience_sort
Sorting algorithms/Patience 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 ...
#AutoHotkey
AutoHotkey
PatienceSort(A){ P:=0, Pile:=[], Result:=[] for k, v in A { Pushed := 0 loop % P { i := A_Index if Pile[i].Count() && (Pile[i, 1] >= v) { Pile[i].InsertAt(1, v) pushed := true break } ...
Give a code snippet in #AutoHotkey 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 | Qui...
christopher/rosetta-code
http://rosettacode.org/wiki/Polymorphism
Polymorphism
Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
#Julia
Julia
mutable struct Point x::Float64 y::Float64 end   Base.show(io::IO, p::Point) = print(io, "Point($(p.x), $(p.y))")   getx(p::Point) = p.x gety(p::Point) = p.y   setx(p::Point, x) = (p.x = x) sety(p::Point, y) = (p.y = y)   mutable struct Circle x::Float64 y::Float64 r::Float64 end   getx(c::Circle) = c.x gety(c::Ci...
Give a code snippet in #Julia Task Create two classes   Point(x,y)   and   Circle(x,y,r)   with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
christopher/rosetta-code
http://rosettacode.org/wiki/First_class_environments
First class environments
According to Wikipedia, "In computing, a first-class object ... is an entity that can be constructed at run-time, passed as a parameter, returned from a subroutine, or assigned into a variable". Often this term is used in the context of "first class functions". In an analogous way, a programming language may support "...
#Lua
Lua
  local envs = { } for i = 1, 12 do -- fallback to the global environment for io and math envs[i] = setmetatable({ count = 0, n = i }, { __index = _G }) end   local code = [[ io.write(("% 4d"):format(n)) if n ~= 1 then count = count + 1 n = (n % 2 == 1) and 3 * n + 1 or math.floor(n / 2) end ]]   while ...
Give a code snippet in #Lua According to Wikipedia, "In computing, a first-class object ... is an entity that can be constructed at run-time, passed as a parameter, returned from a subroutine, or assigned into a variable". Often this term is used in the context of "first class functions". In an analogous way, a progr...
christopher/rosetta-code
http://rosettacode.org/wiki/Repeat_a_string
Repeat a string
Take a string and repeat it some number of times. Example: repeat("ha", 5)   =>   "hahahahaha" If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****"). Other tasks re...
#Yorick
Yorick
array("ha", 5)(sum)
Give a code snippet in #Yorick Take a string and repeat it some number of times. Example: repeat("ha", 5)   =>   "hahahahaha" If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5)...
christopher/rosetta-code
http://rosettacode.org/wiki/Parsing/RPN_calculator_algorithm
Parsing/RPN calculator algorithm
Task Create a stack-based evaluator for an expression in   reverse Polish notation (RPN)   that also shows the changes in the stack as each individual token is processed as a table. Assume an input of a correct, space separated, string of tokens of an RPN expression Test with the RPN expression generated from the...
#Quackery
Quackery
  [ stack ] is switch.arg ( --> [ )   [ switch.arg put ] is switch ( x --> )   [ switch.arg release ] is otherwise ( --> )   [ switch.arg share  != iff ]else[ done otherwise ]'[ do ]done[ ] is ca...
Give a code snippet in #Quackery Task Create a stack-based evaluator for an expression in   reverse Polish notation (RPN)   that also shows the changes in the stack as each individual token is processed as a table. Assume an input of a correct, space separated, string of tokens of an RPN expression Test with the...
christopher/rosetta-code
http://rosettacode.org/wiki/Combinations
Combinations
Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3 0 2 4 0 3 4 1 2 3 1 2 4 1 3 4 2 3 4 ...
#AppleScript
AppleScript
on comb(n, k) set c to {} repeat with i from 1 to k set end of c to i's contents end repeat set r to {c's contents} repeat while my next_comb(c, k, n) set end of r to c's contents end repeat return r end comb   on next_comb(c, k, n) set i to k set c's item i to (c's i...
Give a code snippet in #AppleScript Task Given non-negative integers   m   and   n,   generate all size   m   combinations   of the integers from   0   (zero)   to   n-1   in sorted order   (each combination is sorted and the entire table is sorted). Example 3   comb   5     is: 0 1 2 0 1 3 0 1 4 0 2 3...
christopher/rosetta-code
http://rosettacode.org/wiki/Call_a_foreign-language_function
Call a foreign-language function
Task Show how a foreign language function can be called from the language. As an example, consider calling functions defined in the C language. Create a string containing "Hello World!" of the string type typical to the language. Pass the string content to C's strdup. The content can be copied if necessary. Get the...
#Aikido
Aikido
#include <aikido.h> extern "C" { // need C linkage   // define the function using a macro defined in aikido.h AIKIDO_NATIVE(strdup) { aikido::string *s = paras[0].str; char *p = strdup (s->c_str()); aikido::string *result = new aikido::string(p); free (p); return result; }   }
Give a code snippet in #Aikido Task Show how a foreign language function can be called from the language. As an example, consider calling functions defined in the C language. Create a string containing "Hello World!" of the string type typical to the language. Pass the string content to C's strdup. The content can...
christopher/rosetta-code
http://rosettacode.org/wiki/Sum_digits_of_an_integer
Sum digits of an integer
Task Take a   Natural Number   in a given base and return the sum of its digits:   110         sums to   1   123410   sums to   10   fe16       sums to   29   f0e16     sums to   29
#Swift
Swift
  extension String: Error { func sumDigits(withBase base: Int) throws -> Int { func characterToInt(_ base: Int) -> (Character) -> Int? { return { char in return Int(String(char), radix: base) } }   return try self.map(characterToInt(base)) ...
Give a code snippet in #Swift Task Take a   Natural Number   in a given base and return the sum of its digits:   110         sums to   1   123410   sums to   10   fe16       sums to   29   f0e16     sums to   29
christopher/rosetta-code
http://rosettacode.org/wiki/Fibonacci_word/fractal
Fibonacci word/fractal
The Fibonacci word may be represented as a fractal as described here: (Clicking on the above website   (hal.archives-ouvertes.fr)   will leave a cookie.) For F_wordm start with F_wordCharn=1 Draw a segment forward If current F_wordChar is 0 Turn left if n is even Turn right if n is odd next n and iterate until e...
#REXX
REXX
/*REXX program generates a Fibonacci word, then (normally) displays the fractal curve.*/ parse arg order . /*obtain optional arguments from the CL*/ if order=='' | order=="," then order= 23 /*Not specified? Then use the default*/ tell= order>=0 ...
Give a code snippet in #REXX The Fibonacci word may be represented as a fractal as described here: (Clicking on the above website   (hal.archives-ouvertes.fr)   will leave a cookie.) For F_wordm start with F_wordCharn=1 Draw a segment forward If current F_wordChar is 0 Turn left if n is even Turn right if n is ...
christopher/rosetta-code
http://rosettacode.org/wiki/Grayscale_image
Grayscale image
Many image processing algorithms are defined for grayscale (or else monochromatic) images. Task Extend the data storage type defined on this page to support grayscale images. Define two operations, one to convert a color image to a grayscale image and one for the backward conversion. To get luminance of a color u...
#PHP
PHP
class BitmapGrayscale extends Bitmap { public function toGrayscale(){ for ($i = 0; $i < $this->h; $i++){ for ($j = 0; $j < $this->w; $j++){ $l = ($this->data[$j][$i][0] * 0.2126) + ($this->data[$j][$i][1] * 0.7152) + ($this->data[$j][$i][2] * 0.0722); $l = round($l); ...
Give a code snippet in #PHP Many image processing algorithms are defined for grayscale (or else monochromatic) images. Task Extend the data storage type defined on this page to support grayscale images. Define two operations, one to convert a color image to a grayscale image and one for the backward conversion. ...
christopher/rosetta-code
http://rosettacode.org/wiki/Stack
Stack
Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A stack is a container of elements with   last in, first out   access policy.   Sometimes it also called LIFO. The stack is accessed through its top. The ba...
#SenseTalk
SenseTalk
put () into stack repeat with each item of 1 .. 10 push it into stack end repeat   repeat while stack is not empty pop stack put it end repeat
Give a code snippet in #SenseTalk Data Structure This illustrates a data structure, a means of storing data within a program. You may see other such structures in the Data Structures category. A stack is a container of elements with   last in, first out   access policy.   Sometimes it also called LIFO. The stack i...
christopher/rosetta-code
http://rosettacode.org/wiki/Enforced_immutability
Enforced immutability
Task Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
#PowerBASIC
PowerBASIC
$me = "myname" %age = 35
Give a code snippet in #PowerBASIC Task Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
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...
#Tailspin
Tailspin
  source hundredDoors @: [ 1..100 -> 0 ]; templates toggle def jump: $; $jump..100:$jump -> \(when <?($@hundredDoors($) <=0>)> do @hundredDoors($): 1; otherwise @hundredDoors($): 0;\) -> !VOID end toggle 1..100 -> toggle -> !VOID $@ -> \[i](<=1> ' $i;' !\) ! end hundredDoors   $hundredDoors -> 'Open ...
Give a code snippet in #Tailspin 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/Greatest_element_of_a_list
Greatest element of a list
Task Create a function that returns the maximum value in a provided set of values, where the number of values may not be known until run-time.
#Quackery
Quackery
[ behead swap witheach max ] is [max] ( [ --> n )
Give a code snippet in #Quackery Task Create a function that returns the maximum value in a provided set of values, where the number of values may not be known until run-time.
christopher/rosetta-code
http://rosettacode.org/wiki/Soundex
Soundex
Soundex is an algorithm for creating indices for words based on their pronunciation. Task The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling   (from the   soundex   Wikipedia article). Caution There is a major issue in many of the ...
#Julia
Julia
  using Soundex @assert soundex("Ashcroft") == "A261" # true   # Too trivial? OK. Here is an example not using a package: function soundex(s) char2num = Dict('B'=>1,'F'=>1,'P'=>1,'V'=>1,'C'=>2,'G'=>2,'J'=>2,'K'=>2, 'Q'=>2,'S'=>2,'X'=>2,'Z'=>2,'D'=>3,'T'=>3,'L'=>4,'M'=>5,'N'=>5,'R'=>6) s = replace(s, r"...
Give a code snippet in #Julia Soundex is an algorithm for creating indices for words based on their pronunciation. Task The goal is for homophones to be encoded to the same representation so that they can be matched despite minor differences in spelling   (from the   soundex   Wikipedia article). Caution There i...
christopher/rosetta-code
http://rosettacode.org/wiki/Largest_int_from_concatenated_ints
Largest int from concatenated ints
Task Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer. Use the following two sets of integers as tests   and   show your program output here.   {1, 34, 3, 98, 9, 76, 45, 4}   {54,...
#Run_BASIC
Run BASIC
a1$ = "1, 34, 3, 98, 9, 76, 45, 4" a2$ = "54,546,548,60"   print "Max Num ";a1$;" = ";maxNum$(a1$) print "Max Num ";a2$;" = ";maxNum$(a2$)   function maxNum$(a1$) while word$(a1$,i+1,",") <> "" i = i + 1 a$(i) = trim$(word$(a1$,i,",")) wend   s = 1 while s = 1 s = 0 for j = 1 to i -1 if a$(j)+a$(j+1) < a$(j+1)+a$...
Give a code snippet in #Run_BASIC Task Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer. Use the following two sets of integers as tests   and   show your program output here.   {...
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...
#Clojure
Clojure
  (def burn-prob 0.1) (def new-tree-prob 0.5)   (defn grow-new-tree? [] (> new-tree-prob (rand))) (defn burn-tree? [] (> burn-prob (rand))) (defn tree-maker [] (if (grow-new-tree?) :tree :grass))   (defn make-forest ([] (make-forest 5)) ([size] (take size (repeatedly #(take size (repeatedly tree-maker))))))   (de...
Give a code snippet in #Clojure 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 an...
christopher/rosetta-code
http://rosettacode.org/wiki/Call_a_function
Call a function
Task Demonstrate the different syntax and semantics provided for calling a function. This may include:   Calling a function that requires no arguments   Calling a function with a fixed number of arguments   Calling a function with optional arguments   Calling a function with a variable number of arguments   C...
#ALGOL_W
ALGOL W
% Note, in Algol W, functions are called procedures % % calling a function with no parameters: % f;   % calling a function with a fixed number of parameters % g( 1, 2.3, "4" );   % Algol W does not support optional parameters in general, however constructors for records can % % be called wither with parameters (one for...
Give a code snippet in #ALGOL_W Task Demonstrate the different syntax and semantics provided for calling a function. This may include:   Calling a function that requires no arguments   Calling a function with a fixed number of arguments   Calling a function with optional arguments   Calling a function with a ...
christopher/rosetta-code
http://rosettacode.org/wiki/Long_multiplication
Long multiplication
Task Explicitly implement   long multiplication. This is one possible approach to arbitrary-precision integer algebra. For output, display the result of   264 * 264. Optionally, verify your result against builtin arbitrary precision support. The decimal representation of   264   is: 18,446,744,073,709,551,61...
#CoffeeScript
CoffeeScript
  # This very limited BCD-based collection of functions # allows for long multiplication. It works for positive # numbers only. The assumed data structure is as follows: # BcdInteger.from_integer(4321) == [1, 2, 3, 4]   BcdInteger = from_string: (s) -> arr = [] for c in s arr.unshift parseInt(c) a...
Give a code snippet in #CoffeeScript Task Explicitly implement   long multiplication. This is one possible approach to arbitrary-precision integer algebra. For output, display the result of   264 * 264. Optionally, verify your result against builtin arbitrary precision support. The decimal representation of   ...
christopher/rosetta-code
http://rosettacode.org/wiki/Parallel_brute_force
Parallel brute force
Task Find, through brute force, the five-letter passwords corresponding with the following SHA-256 hashes: 1. 1115dd800feaacefdf481f1f9070374a2a81e27880f187396db67958b207cbad 2. 3a7bd3e2360a3d29eea436fcfb7e44c735d117c42d1c1835420b6b9942dd4f1b 3. 74e1bb62f8dabb8125a58852b63bdf6eaef667cb56ac7f7cdba6d7305c50a22f Your p...
#Racket
Racket
#lang racket/base (require racket/place racket/list racket/match  ;; requires sha package. install it in DrRacket's "File/Install Package..."  ;; or with raco:  ;; % raco pkg install sha sha (only-in openssl/sha1 hex-string->bytes))   (define (brute css targs)...
Give a code snippet in #Racket Task Find, through brute force, the five-letter passwords corresponding with the following SHA-256 hashes: 1. 1115dd800feaacefdf481f1f9070374a2a81e27880f187396db67958b207cbad 2. 3a7bd3e2360a3d29eea436fcfb7e44c735d117c42d1c1835420b6b9942dd4f1b 3. 74e1bb62f8dabb8125a58852b63bdf6eaef667cb...
christopher/rosetta-code
http://rosettacode.org/wiki/Bitmap
Bitmap
Show a basic storage type to handle a simple RGB raster graphics image, and some primitive associated functions. If possible provide a function to allocate an uninitialised image, given its width and height, and provide 3 additional functions:   one to fill an image with a plain RGB color,   one to set a given pixe...
#M2000_Interpreter
M2000 Interpreter
  \ Bitmap width in pixels, height in pixels \ Return a group object with some lambda as members: SetPixel, GetPixel, Image$ \ copyimage \ using Copy x, y Use Image$ we can display image$ to x, y as twips \ we can use x*twipsx, y*twipsy for x,y as pixels Function Bitmap (x as long, y as long) { if x<1 or y<1 ...
Give a code snippet in #M2000_Interpreter Show a basic storage type to handle a simple RGB raster graphics image, and some primitive associated functions. If possible provide a function to allocate an uninitialised image, given its width and height, and provide 3 additional functions:   one to fill an image with a ...
christopher/rosetta-code
http://rosettacode.org/wiki/Topic_variable
Topic variable
Several programming languages offer syntax shortcuts to deal with the notion of "current" or "topic" variable. A topic variable is a special variable with a very short name which can also often be omitted. Demonstrate the utilization and behaviour of the topic variable within the language and explain or demonstrate h...
#Julia
Julia
julia> 3 3 julia> ans * ans, ans - 1 (9, 2)
Give a code snippet in #Julia Several programming languages offer syntax shortcuts to deal with the notion of "current" or "topic" variable. A topic variable is a special variable with a very short name which can also often be omitted. Demonstrate the utilization and behaviour of the topic variable within the langua...
christopher/rosetta-code
http://rosettacode.org/wiki/XML/XPath
XML/XPath
Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Store #45x10^3"> <section name="heal...
#SenseTalk
SenseTalk
Set XMLSource to {{ <inventory title="OmniCorp Store #45x10^3"> <section name="health"> <item upc="123456789" stock="12"> <name>Invisibility Cream</name> <price>14.50</price> <description>Makes you invisible</description> </item> <item upc="445322344" stock="18"> <name>Levitation S...
Give a code snippet in #SenseTalk Perform the following three XPath queries on the XML Document below: //item[1]: Retrieve the first "item" element //price/text(): Perform an action on each "price" element (print it out) //name: Get an array of all the "name" elements XML Document: <inventory title="OmniCorp Sto...
christopher/rosetta-code
http://rosettacode.org/wiki/Return_multiple_values
Return multiple values
Task Show how to return more than one value from a function.
#FALSE
FALSE
[\$@$@*@@/]f: { in: a b, out: a*b a/b } 6 2f;! .` ,. { 3 12 }
Give a code snippet in #FALSE Task Show how to return more than one value from a function.
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...
#Seed7
Seed7
$ include "seed7_05.s7i";   const proc: main is func local var integer: number is 0; begin for number range 1 to 10 step 2 do writeln(number); end for; end func;
Give a code snippet in #Seed7 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/Currying
Currying
This page uses content from Wikipedia. The original article was at Currying. 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 Create a simple demonstrative example of Currying in a specific la...
#M2000_Interpreter
M2000 Interpreter
  Module LikeCpp { divide=lambda (x, y)->x/y partsof120=lambda divide ->divide(![], 120) Print "half of 120 is ";partsof120(2) Print "a third is ";partsof120(3) Print "and a quarter is ";partsof120(4) } LikeCpp   Module Joke { \\ we can call F1(), with any number of arguments, and a...
Give a code snippet in #M2000_Interpreter This page uses content from Wikipedia. The original article was at Currying. 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 Create a simple demonst...
christopher/rosetta-code
http://rosettacode.org/wiki/URL_decoding
URL decoding
This task   (the reverse of   URL encoding   and distinct from   URL parser)   is to provide a function or mechanism to convert an URL-encoded string into its original unencoded form. Test cases   The encoded string   "http%3A%2F%2Ffoo%20bar%2F"   should be reverted to the unencoded form   "http://foo bar/".   Th...
#M2000_Interpreter
M2000 Interpreter
  Module CheckIt { Function decodeUrl$(a$) { DIM a$() a$()=Piece$(a$, "%") if len(a$())=1 then =str$(a$):exit k=each(a$(),2) \\ convert to one byte per character using str$(string) acc$=str$(a$(0)) While k { ...
Give a code snippet in #M2000_Interpreter This task   (the reverse of   URL encoding   and distinct from   URL parser)   is to provide a function or mechanism to convert an URL-encoded string into its original unencoded form. Test cases   The encoded string   "http%3A%2F%2Ffoo%20bar%2F"   should be reverted to th...
christopher/rosetta-code
http://rosettacode.org/wiki/UTF-8_encode_and_decode
UTF-8 encode and decode
As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets. The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the...
#Seed7
Seed7
$ include "seed7_05.s7i"; include "unicode.s7i"; include "console.s7i"; include "bytedata.s7i";   const proc: main is func local var char: ch is ' '; var string: utf8 is ""; begin OUT := STD_CONSOLE; writeln("Character Unicode UTF-8 encoding (hex) Decoded"); writeln("-------------------...
Give a code snippet in #Seed7 As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets. The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes rep...
christopher/rosetta-code
http://rosettacode.org/wiki/Burrows%E2%80%93Wheeler_transform
Burrows–Wheeler transform
This page uses content from Wikipedia. The original article was at Burrows–Wheeler_transform. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) The Burrows–Wheeler transform (BWT, also called block-s...
#Go
Go
package main   import ( "fmt" "sort" "strings" )   const stx = "\002" const etx = "\003"   func bwt(s string) (string, error) { if strings.Index(s, stx) >= 0 || strings.Index(s, etx) >= 0 { return "", fmt.Errorf("String can't contain STX or ETX") } s = stx + s + etx le := len(s) ...
Give a code snippet in #Go This page uses content from Wikipedia. The original article was at Burrows–Wheeler_transform. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) The Burrows–Wheeler transfo...
christopher/rosetta-code
http://rosettacode.org/wiki/Comma_quibbling
Comma quibbling
Comma quibbling is a task originally set by Eric Lippert in his blog. Task Write a function to generate a string output which is the concatenation of input words from a list/sequence where: An input of no words produces the output string of just the two brace characters "{}". An input of just one word, e.g. ["AB...
#Raku
Raku
sub comma-quibbling(@A) { <{ }>.join: @A < 2 ?? @A !! "@A[0..*-2].join(', ') and @A[*-1]"; }   say comma-quibbling($_) for [], [<ABC>], [<ABC DEF>], [<ABC DEF G H>];
Give a code snippet in #Raku Comma quibbling is a task originally set by Eric Lippert in his blog. Task Write a function to generate a string output which is the concatenation of input words from a list/sequence where: An input of no words produces the output string of just the two brace characters "{}". An inp...
christopher/rosetta-code
http://rosettacode.org/wiki/24_game
24 game
The 24 Game tests one's mental arithmetic. Task Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed. The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digits, used exactly once each. T...
#PowerShell
PowerShell
  CLS   Function isNumeric ($x) { $x2 = 0 $isNum = [System.Int32]::TryParse($x,[ref]$x2) Return $isNum }   $NumberArray = @() While( $NumberArray.Count -lt 4 ){ $NumberArray += Random -Minimum 1 -Maximum 10 }   Write-Host @" Welcome to the 24 game!   Here are your numbers: $($NumberArray -join ","). Use...
Give a code snippet in #PowerShell The 24 Game tests one's mental arithmetic. Task Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed. The program should prompt for the player to enter an arithmetic expression using just those, and all of those fo...
christopher/rosetta-code
http://rosettacode.org/wiki/Interactive_programming_(repl)
Interactive programming (repl)
Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. Task Show how to start this...
#BASIC
BASIC
10 DEF FN f$(a$, b$, s$) = a$+s$+s$+b$ PRINT FN f$("Rosetta", "Code", ":")
Give a code snippet in #BASIC Many language implementations come with an interactive mode. This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions. An interactive mode may also be known as a command mode,   a read-eval-print loop (REPL),   or a shell. ...
christopher/rosetta-code
http://rosettacode.org/wiki/Catalan_numbers
Catalan numbers
Catalan numbers You are encouraged to solve this task according to the task description, using any language you may know. Catalan numbers are a sequence of numbers which can be defined directly: C n = 1 n + 1 ( 2 n n ) = ( 2 n ) ! ( n + 1 ) ! n !  for  n ≥ 0. {\displaystyle C...
#Common_Lisp
Common Lisp
(defun catalan1 (n) ;; factorial. CLISP actually has "!" defined for this (labels ((! (x) (if (zerop x) 1 (* x (! (1- x)))))) (/ (! (* 2 n)) (! (1+ n)) (! n))))   ;; cache (defparameter *catalans* (make-array 5 :fill-pointer 0 :adjustable t :element-type 'integer)) (defun catalan2 (n)...
Give a code snippet in #Common_Lisp Catalan numbers You are encouraged to solve this task according to the task description, using any language you may know. Catalan numbers are a sequence of numbers which can be defined directly: C n = 1 n + 1 ( 2 n n ) = ( 2 n ) ! ( n + 1 ) ! n ! ...
christopher/rosetta-code
http://rosettacode.org/wiki/Arithmetic/Complex
Arithmetic/Complex
A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaystyle i}   is   √ -1  Typica...
#Java
Java
public class Complex { public final double real; public final double imag;   public Complex() { this(0, 0); }   public Complex(double r, double i) { real = r; imag = i; }   public Complex add(Complex b) { return new Complex(this.real + b.real, this.imag + b.im...
Give a code snippet in #Java A   complex number   is a number which can be written as: a + b × i {\displaystyle a+b\times i} (sometimes shown as: b + a × i {\displaystyle b+a\times i} where   a {\displaystyle a}   and   b {\displaystyle b}   are real numbers,   and   i {\displaysty...
christopher/rosetta-code
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#11l
11l
  * Binary interger (H,F) I2 DS H half word 2 bytes I4 DS F full word 4 bytes * Real (floating point) (E,D,L) X4 DS E short 4 bytes X8 DS D double 8 bytes X16 DS L extended 16 bytes * ...
Give a code snippet in #11l Task Demonstrate how to specify the minimum size of a variable or a data type.
christopher/rosetta-code
http://rosettacode.org/wiki/Text_processing/Max_licenses_in_use
Text processing/Max licenses in use
A company currently pays a fixed sum for the use of a particular licensed software package.   In determining if it has a good deal it decides to calculate its maximum use of the software from its license management log file. Assume the software's licensing daemon faithfully records a checkout event when a copy of the ...
#zkl
zkl
nOut,maxOut,maxTimes:=0,-1,List(); foreach job in (File("mlijobs.txt")){ _,status,_,date:=job.split(); nOut+=( if(status.toUpper()=="OUT") 1 else -1 ); if(nOut>maxOut){ maxOut=nOut; maxTimes.clear(); } if(nOut==maxOut) maxTimes.append(date); } println(("Maximum simultaneous license use is %d at" " ...
Give a code snippet in #zkl A company currently pays a fixed sum for the use of a particular licensed software package.   In determining if it has a good deal it decides to calculate its maximum use of the software from its license management log file. Assume the software's licensing daemon faithfully records a check...
christopher/rosetta-code
http://rosettacode.org/wiki/Anagrams/Deranged_anagrams
Anagrams/Deranged anagrams
Two or more words are said to be anagrams if they have the same characters, but in a different order. By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words. Task[edit] Use the word list at uni...
#Rust
Rust
//! Deranged anagrams use std::cmp::Ordering; use std::collections::HashMap; use std::fs::File; use std::io; use std::io::BufReader; use std::io::BufRead; use std::usize::MAX;   /// Get words from unix dictionary file pub fn get_words() -> Result<Vec<String>, io::Error> { let mut words = vec!(); // open file ...
Give a code snippet in #Rust Two or more words are said to be anagrams if they have the same characters, but in a different order. By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words. Task[...
christopher/rosetta-code
http://rosettacode.org/wiki/Conditional_structures
Conditional structures
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Common conditional structures include ...
#Nanoquery
Nanoquery
if x = 0 foo() else if x = 1 bar() else if x = 2 baz() else boz() end
Give a code snippet in #Nanoquery Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Task List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions. Com...
christopher/rosetta-code
http://rosettacode.org/wiki/First-class_functions
First-class functions
A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming: Create new functions from preexisting functions at run-time Store functions in collections Use functions as arguments to other functions Use functions as retu...
#Elena
Elena
import system'routines; import system'math; import extensions'routines; import extensions'math;   extension op { compose(f,g) = f(g(self)); }   public program() { var fs := new object[]{ mssgconst sin<mathOp>[1], mssgconst cos<mathOp>[1], (x => power(x, 3.0r)) }; var gs := new object[]{ mssgconst arcs...
Give a code snippet in #Elena A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming: Create new functions from preexisting functions at run-time Store functions in collections Use functions as arguments to other f...
christopher/rosetta-code
http://rosettacode.org/wiki/Singly-linked_list/Traversal
Singly-linked list/Traversal
Traverse from the beginning of a singly-linked list to the end. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: Definition, Usage Set Singly-linked ...
#Common_Lisp
Common Lisp
(dolist (x list) (print x))
Give a code snippet in #Common_Lisp Traverse from the beginning of a singly-linked list to the end. See also Array Associative array: Creation, Iteration Collections Compound data type Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal Linked list Queue: D...
christopher/rosetta-code
http://rosettacode.org/wiki/Count_in_octal
Count in octal
Task Produce a sequential count in octal,   starting at zero,   and using an increment of a one for each consecutive number. Each number should appear on a single line,   and the program should count until terminated,   or until the maximum value of the numeric type in use is reached. Related task   Integer sequ...
#Clojure
Clojure
(doseq [i (range)] (println (format "%o" i)))
Give a code snippet in #Clojure Task Produce a sequential count in octal,   starting at zero,   and using an increment of a one for each consecutive number. Each number should appear on a single line,   and the program should count until terminated,   or until the maximum value of the numeric type in use is reached....
christopher/rosetta-code
http://rosettacode.org/wiki/Hello_world/Line_printer
Hello world/Line printer
Task Cause a line printer attached to the computer to print a line containing the message:   Hello World! Note A line printer is not the same as standard output. A   line printer   was an older-style printer which prints one line at a time to a continuous ream of paper. With some systems, a line printer can be...
#Factor
Factor
( scratchpad ) USE: io.encodings.utf8 ( scratchpad ) USE: io.launcher ( scratchpad ) "lpr" utf8 [ "Hello World!" print ] with-process-writer
Give a code snippet in #Factor Task Cause a line printer attached to the computer to print a line containing the message:   Hello World! Note A line printer is not the same as standard output. A   line printer   was an older-style printer which prints one line at a time to a continuous ream of paper. With som...
christopher/rosetta-code