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http://rosettacode.org/wiki/Chinese_remainder_theorem
Chinese remainder theorem
Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displaystyle a_{1}} ,   a 2 ...
#Lobster
Lobster
import std   def extended_gcd(a, b): var s = 0 var old_s = 1 var t = 1 var old_t = 0 var r = b var old_r = a   while r != 0: let quotient = old_r / r old_r, r = r, old_r - quotient * r old_s, s = s, old_s - quotient * s old_t, t = t, old_t - quotient * t   ...
Give a code snippet in #Lobster Suppose   n 1 {\displaystyle n_{1}} ,   n 2 {\displaystyle n_{2}} ,   … {\displaystyle \ldots } ,   n k {\displaystyle n_{k}}   are positive integers that are pairwise co-prime.   Then, for any given sequence of integers   a 1 {\displa...
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 ...
#Fancy
Fancy
class Fixnum { def fib { match self -> { case 0 -> 0 case 1 -> 1 case _ -> self - 1 fib + (self - 2 fib) } } }   15 times: |x| { x fib println }  
Give a code snippet in #Fancy 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...
christopher/rosetta-code
http://rosettacode.org/wiki/Primorial_numbers
Primorial numbers
Primorial numbers are those formed by multiplying successive prime numbers. The primorial number series is:   primorial(0) =         1       (by definition)   primorial(1) =         2       (2)   primorial(2) =         6       (2×3)   primorial(3) =       30       (2×3×5)   primorial(4) =     210       (2×3×5×...
#PARI.2FGP
PARI/GP
nthprimorial(n)=prod(i=1,n,prime(i)); vector(10,i,nthprimorial(i-1)) vector(5,n,#Str(nthprimorial(10^n))) #Str(nthprimorial(10^6))
Give a code snippet in #PARI.2FGP Primorial numbers are those formed by multiplying successive prime numbers. The primorial number series is:   primorial(0) =         1       (by definition)   primorial(1) =         2       (2)   primorial(2) =         6       (2×3)   primorial(3) =       30       (2×3×5)   p...
christopher/rosetta-code
http://rosettacode.org/wiki/Literals/Floating_point
Literals/Floating point
Programming languages have different ways of expressing floating-point literals. Task Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features. You may want to include a regular expression or BNF/ABNF/EBNF defining allowable fo...
#Elixir
Elixir
iex(180)> 0.123 0.123 iex(181)> -123.4 -123.4 iex(182)> 1.23e4 1.23e4 iex(183)> 1.2e-3 0.0012 iex(184)> 1.23E4 1.23e4 iex(185)> 10_000.0 1.0e4 iex(186)> .5 ** (SyntaxError) iex:186: syntax error before: '.'   iex(186)> 2. + 3 ** (CompileError) iex:186: invalid call 2.+(3)   iex(187)> 1e4 ** (SyntaxError) iex:187: synta...
Give a code snippet in #Elixir Programming languages have different ways of expressing floating-point literals. Task Show how floating-point literals can be expressed in your language: decimal or other bases, exponential notation, and any other special features. You may want to include a regular expression or BNF...
christopher/rosetta-code
http://rosettacode.org/wiki/Non-continuous_subsequences
Non-continuous subsequences
Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.) A subsequence contains some subset of the elements of this sequence, in the same order. A continuous subsequence is one in which no elements are missing between the first and last elements of the subseque...
#D
D
T[][] ncsub(T)(in T[] seq, in uint s=0) pure nothrow @safe { if (seq.length) { typeof(return) aux; foreach (ys; ncsub(seq[1 .. $], s + !(s % 2))) aux ~= seq[0] ~ ys; return aux ~ ncsub(seq[1 .. $], s + s % 2); } else return new typeof(return)(s >= 3, 0); }   void main...
Give a code snippet in #D Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.) A subsequence contains some subset of the elements of this sequence, in the same order. A continuous subsequence is one in which no elements are missing between the first and la...
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...
#Wortel
Wortel
; the following number expression calculcates the nth Catalan number #~ddiFSFmSoFSn ; which stands for: dup dup inc fac swap fac mult swap double fac swap divide ; to get the first 15 Catalan numbers we map this function over a list from 0 to 15 !*#~ddiFSFmSoFSn @til 15 ; returns [1 1 2 5 14 42 132 429 1430 4862 16796 ...
Give a code snippet in #Wortel 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/Perfect_numbers
Perfect numbers
Write a function which says whether a number is perfect. A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself. Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself). Note:   The faster   Luca...
#Scala
Scala
def perfectInt(input: Int) = ((2 to sqrt(input).toInt).collect {case x if input % x == 0 => x + input / x}).sum == input - 1
Give a code snippet in #Scala Write a function which says whether a number is perfect. A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself. Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Bubble_sort
Sorting algorithms/Bubble 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 ...
#SPARK
SPARK
package Bubble is   type Arr is array(Integer range <>) of Integer;   procedure Sort (A : in out Arr); --# derives A from *;   end Bubble;     package body Bubble is procedure Sort (A : in out Arr) is Finished : Boolean; Temp  : Integer; begin if A'Last /= A'First then lo...
Give a code snippet in #SPARK 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/Old_Russian_measure_of_length
Old Russian measure of length
Task Write a program to perform a conversion of the old Russian measures of length to the metric system   (and vice versa). It is an example of a linear transformation of several variables. The program should accept a single value in a selected unit of measurement, and convert and return it to the other units: ...
#Go
Go
package main   import ( "bufio" "fmt" "os" "strconv" "strings" )   func main() { units := []string{ "tochka", "liniya", "dyuim", "vershok", "piad", "fut", "arshin", "sazhen", "versta", "milia", "centimeter", "meter", "kilometer", }   convs := []float32{ 0....
Give a code snippet in #Go Task Write a program to perform a conversion of the old Russian measures of length to the metric system   (and vice versa). It is an example of a linear transformation of several variables. The program should accept a single value in a selected unit of measurement, and convert and ret...
christopher/rosetta-code
http://rosettacode.org/wiki/Short-circuit_evaluation
Short-circuit evaluation
Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Assume functions   a   and   b   return boolean values,   and further, the execution of function   b   takes considerable resources without side effects, an...
#Tcl
Tcl
package require Tcl 8.5 proc tcl::mathfunc::a boolean { puts "a($boolean) called" return $boolean } proc tcl::mathfunc::b boolean { puts "b($boolean) called" return $boolean }   foreach i {false true} { foreach j {false true} { set x [expr {a($i) && b($j)}] puts "x = a($i) && b($j) =...
Give a code snippet in #Tcl Control Structures These are examples of control structures. You may also be interested in: Conditional structures Exceptions Flow-control structures Loops Assume functions   a   and   b   return boolean values,   and further, the execution of function   b   takes considerable resou...
christopher/rosetta-code
http://rosettacode.org/wiki/Truncate_a_file
Truncate a file
Task Truncate a file to a specific length.   This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes). Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating a temporary file of a reduced...
#PL.2FI
PL/I
  /* Parameters to be read in by the program are: */ /* 1. the name of the file to be truncated, and */ /* 2. the size of file after truncation. */   truncate_file: procedure options (main); /* 12 July 2012 */ declare (i, n) fixed binary (31); declare filename character(50) varying; declare in fil...
Give a code snippet in #PL.2FI Task Truncate a file to a specific length.   This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes). Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creati...
christopher/rosetta-code
http://rosettacode.org/wiki/Take_notes_on_the_command_line
Take notes on the command line
Take notes on the command line is part of Short Circuit's Console Program Basics selection. Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists. If NOTES has arguments, the current date and time are appended to the local NOTES.TXT followed by a newline. Then al...
#Scala
Scala
import java.io.{ FileNotFoundException, FileOutputStream, PrintStream } import java.time.LocalDateTime   object TakeNotes extends App { val notesFileName = "notes.txt" if (args.length > 0) { val ps = new PrintStream(new FileOutputStream(notesFileName, true)) ps.println(LocalDateTime.now() + args.mkString("\...
Give a code snippet in #Scala Take notes on the command line is part of Short Circuit's Console Program Basics selection. Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists. If NOTES has arguments, the current date and time are appended to the local NOTES.TXT...
christopher/rosetta-code
http://rosettacode.org/wiki/Strip_a_set_of_characters_from_a_string
Strip a set of characters from a string
Task Create a function that strips a set of characters from a string. The function should take two arguments:   a string to be stripped   a string containing the set of characters to be stripped The returned string should contain the first string, stripped of any characters in the second argument: print str...
#JavaScript
JavaScript
function stripchars(string, chars) { return string.replace(RegExp('['+chars+']','g'), ''); }
Give a code snippet in #JavaScript Task Create a function that strips a set of characters from a string. The function should take two arguments:   a string to be stripped   a string containing the set of characters to be stripped The returned string should contain the first string, stripped of any characters...
christopher/rosetta-code
http://rosettacode.org/wiki/Roots_of_a_quadratic_function
Roots of a quadratic function
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Write a program to find the roots of a quadratic equation, i.e., solve the equation a x 2 + b x + c = 0 {\displaystyle ax^{2}+bx+c=0} . Your program must correctly handle n...
#Kotlin
Kotlin
import java.lang.Math.*   data class Equation(val a: Double, val b: Double, val c: Double) { data class Complex(val r: Double, val i: Double) { override fun toString() = when { i == 0.0 -> r.toString() r == 0.0 -> "${i}i" else -> "$r + ${i}i" } }   data cl...
Give a code snippet in #Kotlin This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task. Write a program to find the roots of a quadratic equation, i.e., solve the equation a x 2 + b x + c = 0 {\displaystyle ax^{2}+bx+c=0} . Your...
christopher/rosetta-code
http://rosettacode.org/wiki/Binary_strings
Binary strings
Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks. This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings according to Wikipedia) for those la...
#Seed7
Seed7
var string: stri is "asdf"; # variable declaration const string: stri is "jkl"; # constant declaration
Give a code snippet in #Seed7 Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks. This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings accor...
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.
#Logtalk
Logtalk
  max([X| Xs], Max) :- max(Xs, X, Max).   max([], Max, Max). max([X| Xs], Aux, Max) :- ( X @> Aux -> max(Xs, X, Max) ; max(Xs, Aux, Max) ).
Give a code snippet in #Logtalk 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/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.
#APL
APL
NONSQUARE←{(⍳⍵)+⌊0.5+(⍳⍵)*0.5} NONSQUARE 22 2 3 5 6 7 8 10 11 12 13 14 15 17 18 19 20 21 22 23 24 26 27
Give a code snippet in #APL 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/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...
#PowerShell
PowerShell
function pow($a, [int]$b) { if ($b -eq -1) { return 1/$a } if ($b -eq 0) { return 1 } if ($b -eq 1) { return $a } if ($b -lt 0) { $rec = $true # reciprocal needed $b = -$b }   $result = $a 2..$b | ForEach-Object { $result *= $a }   if ($rec) { return...
Give a code snippet in #PowerShell 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 (o...
christopher/rosetta-code
http://rosettacode.org/wiki/Copy_a_string
Copy a string
This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting W...
#Transd
Transd
#lang transd   MainModule : { _start: (λ (with s "Hello!" s1 "" s2 "" (= s1 s) // duplication of 's' content (rebind s2 s) // another reference to 's' (= s "Good bye!") (lout s) (lout s1) (lout s2) ) ) }
Give a code snippet in #Transd This task is about copying a string. Task Where it is relevant, distinguish between copying the contents of a string versus making an additional reference to an existing string. Other tasks related to string operations: Metrics Array length String length Copy a string Empty ...
christopher/rosetta-code
http://rosettacode.org/wiki/Sum_multiples_of_3_and_5
Sum multiples of 3 and 5
Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
#NetRexx
NetRexx
/* NetRexx */ options replace format comments java crossref symbols nobinary numeric digits 40   runSample(arg) return   -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ method summing(maxLimit = 1000) public static mult = 0 loop mv = 0 while mv < maxLimit if mv // 3 = 0 | mv // ...
Give a code snippet in #NetRexx Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
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...
#Nanoquery
Nanoquery
while true println "SPAM" end
Give a code snippet in #Nanoquery 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/Truth_table
Truth table
A truth table is a display of the inputs to, and the output of a Boolean function organized as a table where each row gives one combination of input values and the corresponding value of the function. Task Input a Boolean function from the user as a string then calculate and print a formatted truth table for the g...
#Python
Python
from itertools import product   while True: bexp = input('\nBoolean expression: ') bexp = bexp.strip() if not bexp: print("\nThank you") break code = compile(bexp, '<string>', 'eval') names = code.co_names print('\n' + ' '.join(names), ':', bexp) for values in product(range(2...
Give a code snippet in #Python A truth table is a display of the inputs to, and the output of a Boolean function organized as a table where each row gives one combination of input values and the corresponding value of the function. Task Input a Boolean function from the user as a string then calculate and print a...
christopher/rosetta-code
http://rosettacode.org/wiki/Entropy/Narcissist
Entropy/Narcissist
Task Write a computer program that computes and shows its own   entropy. Related Tasks   Fibonacci_word   Entropy
#AWK
AWK
  BEGIN{FS="" RS="\x04"#EOF getline<"entropy.awk" for(i=1;i<=NF;i++)H[$i]++ for(i in H)E-=(h=H[i]/NF)*log(h) print "bytes ",NF," entropy ",E/log(2) exit}
Give a code snippet in #AWK Task Write a computer program that computes and shows its own   entropy. Related Tasks   Fibonacci_word   Entropy
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...
#Nim
Nim
if problem1: quit QuitFailure   if problem2: quit "There is a problem", QuitFailure
Give a code snippet in #Nim 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/Atomic_updates
Atomic updates
Task Define a data type consisting of a fixed number of 'buckets', each containing a nonnegative integer value, which supports operations to: get the current value of any bucket remove a specified amount from one specified bucket and add it to another, preserving the total of all bucket values, and clamping the t...
#Kotlin
Kotlin
// version 1.2.0   import java.util.concurrent.ThreadLocalRandom import kotlin.concurrent.thread   const val NUM_BUCKETS = 10   class Buckets(data: IntArray) { private val data = data.copyOf()   operator fun get(index: Int) = synchronized(data) { data[index] }   fun transfer(srcIndex: Int, dstIndex: Int, am...
Give a code snippet in #Kotlin Task Define a data type consisting of a fixed number of 'buckets', each containing a nonnegative integer value, which supports operations to: get the current value of any bucket remove a specified amount from one specified bucket and add it to another, preserving the total of all b...
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: ...
#Zig
Zig
const std = @import("std");   const a1: []const u8 = &[_]u8{ 'a', 'b', 'c' }; const a2: []const u8 = &[_]u8{ 'A', 'B', 'C' }; const a3: []const u8 = &[_]u8{ '1', '2', '3' };   pub fn main() !void { for (a1) |_, i| try std.io.getStdOut().writer().print("{c} {c} {d}\n", .{ a1[i], a2[i], a3[i] }); }
Give a code snippet in #Zig 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 exampl...
christopher/rosetta-code
http://rosettacode.org/wiki/File_input/output
File input/output
File input/output is part of Short Circuit's Console Program Basics selection. Task Create a file called   "output.txt",   and place in it the contents of the file   "input.txt",   via an intermediate variable. In other words, your program will demonstrate:   how to read from a file into a variable   how to write ...
#FreeBASIC
FreeBASIC
' FB 1.05.0 Win64   /' input.txt contains:   The quick brown fox jumps over the lazy dog. Empty vessels make most noise. Too many chefs spoil the broth. A rolling stone gathers no moss. '/   Open "output.txt" For Output As #1 Open "input.txt" For Input As #2 Dim line_ As String ' note that line is a keyword   While N...
Give a code snippet in #FreeBASIC File input/output is part of Short Circuit's Console Program Basics selection. Task Create a file called   "output.txt",   and place in it the contents of the file   "input.txt",   via an intermediate variable. In other words, your program will demonstrate:   how to read from a fi...
christopher/rosetta-code
http://rosettacode.org/wiki/Maze_generation
Maze generation
This page uses content from Wikipedia. The original article was at Maze generation algorithm. 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 Generate and show a maze, using the simple Depth...
#M2000_Interpreter
M2000 Interpreter
  Module Maze { width% = 40 height% = 20 \\ we can use DIM maze$(0 to width%,0 to height%)="#" \\ so we can delete the two For loops DIM maze$(0 to width%,0 to height%) FOR x% = 0 TO width% FOR y% = 0 TO height% maze$(x%, y%) = "#" NEXT y% NE...
Give a code snippet in #M2000_Interpreter This page uses content from Wikipedia. The original article was at Maze generation algorithm. 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 Gener...
christopher/rosetta-code
http://rosettacode.org/wiki/Carmichael_3_strong_pseudoprimes
Carmichael 3 strong pseudoprimes
A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it. The   Miller Rabin Test   uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this. The purpose of this task is to investigate such numbers using a met...
#Racket
Racket
  #lang racket (require math)   (for ([p1 (in-range 3 62)] #:when (prime? p1)) (for ([h3 (in-range 2 p1)]) (define g (+ p1 h3)) (let next ([d 1]) (when (< d g) (when (and (zero? (modulo (* g (- p1 1)) d)) (= (modulo (- (sqr p1)) h3) (modulo d h3))) (define p2 (+ 1 (q...
Give a code snippet in #Racket A lot of composite numbers can be separated from primes by Fermat's Little Theorem, but there are some that completely confound it. The   Miller Rabin Test   uses a combination of Fermat's Little Theorem and Chinese Division Theorem to overcome this. The purpose of this task is to inve...
christopher/rosetta-code
http://rosettacode.org/wiki/Constrained_genericity
Constrained genericity
Constrained genericity or bounded quantification means that a parametrized type or function (see parametric polymorphism) can only be instantiated on types fulfilling some conditions, even if those conditions are not used in that function. Say a type is called "eatable" if you can call the function eat on it. Write a ...
#Crystal
Crystal
class Apple def eat end end   class Carrot def eat end end   class FoodBox(T) def initialize(@data : Array(T)) {% if T.union? %} {% raise "All items should be eatable" unless T.union_types.all? &.has_method?(:eat) %} {% else %} {% raise "Items should be eatable" unless T.has_method?(:eat) %} ...
Give a code snippet in #Crystal Constrained genericity or bounded quantification means that a parametrized type or function (see parametric polymorphism) can only be instantiated on types fulfilling some conditions, even if those conditions are not used in that function. Say a type is called "eatable" if you can call...
christopher/rosetta-code
http://rosettacode.org/wiki/Sockets
Sockets
For this exercise a program is open a socket to localhost on port 256 and send the message "hello socket world" before closing the socket. Catching any exceptions or errors is not required.
#zkl
zkl
var s=Network.TCPClientSocket.connectTo("localhost",256); s.write("hello socket world"); //-->18 s.close();
Give a code snippet in #zkl For this exercise a program is open a socket to localhost on port 256 and send the message "hello socket world" before closing the socket. Catching any exceptions or errors is not required.
christopher/rosetta-code
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric
Determine if a string is numeric
Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metrics Array length String length Cop...
#PowerShell
PowerShell
function isNumeric ($x) { try { 0 + $x | Out-Null return $true } catch { return $false } }
Give a code snippet in #PowerShell Task Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings. Other tasks related to string operations: Metri...
christopher/rosetta-code
http://rosettacode.org/wiki/Repeat_a_string
Repeat a string
Take a string and repeat it some number of times. Example: repeat("ha", 5)   =>   "hahahahaha" If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****"). Other tasks re...
#Bracmat
Bracmat
(repeat= string N rep .  !arg:(?string.?N) & !string:?rep & whl ' (!N+-1:>0:?N&!string !rep:?rep) & str$!rep );
Give a code snippet in #Bracmat 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/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.
#ALGOL_68
ALGOL 68
IF FILE output; STRING output file name = "output.txt"; open( output, output file name, stand out channel ) = 0 THEN # file opened OK # put( output, ( "line 1", newline, "line 2", newline ) ); close( output ) ELSE # unable to open the output file # print( ( "Cannot open ", output f...
Give a code snippet in #ALGOL_68 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/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...
#Groovy
Groovy
final random = new Random() final input = new Scanner(System.in)     def evaluate = { expr -> if (expr == 'QUIT') { return 'QUIT' } else { try { Eval.me(expr.replaceAll(/(\d)/, '$1.0')) } catch (e) { 'syntax error' } } }     def readGuess = { digits -> while (true) { prin...
Give a code snippet in #Groovy The 24 Game tests one's mental arithmetic. Task Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed. The program should prompt for the player to enter an arithmetic expression using just those, and all of those four d...
christopher/rosetta-code
http://rosettacode.org/wiki/Text_processing/2
Text processing/2
The following task concerns data that came from a pollution monitoring station with twenty-four instruments monitoring twenty-four aspects of pollution in the air. Periodically a record is added to the file, each record being a line of 49 fields separated by white-space, which can be one or more space or tab characters...
#M2000_Interpreter
M2000 Interpreter
Module TestThis { Document a$, exp$ \\ automatic find the enconding and the line break Load.doc a$, "readings.txt" m=0 n=doc.par(a$) k=list nl$={ } l=0 exp$=format$("Records: {0}", n)+nl$ For i=1 to n b$=paragraph$(a$, i) If exist(k,Left$(b$, 10)) then m++ : where=eval(k) exp$=format$("Duplicate fo...
Give a code snippet in #M2000_Interpreter The following task concerns data that came from a pollution monitoring station with twenty-four instruments monitoring twenty-four aspects of pollution in the air. Periodically a record is added to the file, each record being a line of 49 fields separated by white-space, which...
christopher/rosetta-code
http://rosettacode.org/wiki/Forward_difference
Forward difference
Task Provide code that produces a list of numbers which is the   nth  order forward difference, given a non-negative integer (specifying the order) and a list of numbers. The first-order forward difference of a list of numbers   A   is a new list   B,   where   Bn = An+1 - An. List   B   should have one fewer elem...
#OCaml
OCaml
let rec forward_difference = function a :: (b :: _ as xs) -> b - a :: forward_difference xs | _ -> []   let rec nth_forward_difference n xs = if n = 0 then xs else nth_forward_difference (pred n) (forward_difference xs)
Give a code snippet in #OCaml Task Provide code that produces a list of numbers which is the   nth  order forward difference, given a non-negative integer (specifying the order) and a list of numbers. The first-order forward difference of a list of numbers   A   is a new list   B,   where   Bn = An+1 - An. List  ...
christopher/rosetta-code
http://rosettacode.org/wiki/Numerical_integration/Gauss-Legendre_Quadrature
Numerical integration/Gauss-Legendre Quadrature
In a general Gaussian quadrature rule, an definite integral of f ( x ) {\displaystyle f(x)} is first approximated over the interval [ − 1 , 1 ] {\displaystyle [-1,1]} by a polynomial approximable function g ( x ) {\displaystyle g(x)} and a known weighting function W ( x ) {\displaystyle ...
#C.2B.2B
C++
#include <iostream> #include <iomanip> #include <cmath>   namespace Rosetta {   /*! Implementation of Gauss-Legendre quadrature * http://en.wikipedia.org/wiki/Gaussian_quadrature * http://rosettacode.org/wiki/Numerical_integration/Gauss-Legendre_Quadrature * */ template <int N> class Gaus...
Give a code snippet in #C.2B.2B In a general Gaussian quadrature rule, an definite integral of f ( x ) {\displaystyle f(x)} is first approximated over the interval [ − 1 , 1 ] {\displaystyle [-1,1]} by a polynomial approximable function g ( x ) {\displaystyle g(x)} and a known weighting funct...
christopher/rosetta-code
http://rosettacode.org/wiki/Test_a_function
Test a function
Task Using a well-known testing-specific library/module/suite for your language, write some tests for your language's entry in Palindrome. If your language does not have a testing specific library well known to the language's community then state this or omit the language.
#R
R
checkTrue(palindroc("aba")) # TRUE checkTrue(!palindroc("ab")) # TRUE checkException(palindroc()) # TRUE checkTrue(palindroc("")) # Error. Uh-oh, there's a bug in the function
Give a code snippet in #R Task Using a well-known testing-specific library/module/suite for your language, write some tests for your language's entry in Palindrome. If your language does not have a testing specific library well known to the language's community then state this or omit the language.
christopher/rosetta-code
http://rosettacode.org/wiki/Cumulative_standard_deviation
Cumulative standard deviation
Task[edit] Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series. The task implementation should use the most natural programming style of those listed for the function in the implementation langu...
#Clojure
Clojure
  (defn stateful-std-deviation[x] (letfn [(std-dev[x] (let [v (deref (find-var (symbol (str *ns* "/v"))))] (swap! v conj x) (let [m (/ (reduce + @v) (count @v))] (Math/sqrt (/ (reduce + (map #(* (- m %) (- m %)) @v)) (count @v))))))] (when (nil? (resolve 'v)...
Give a code snippet in #Clojure Task[edit] Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series. The task implementation should use the most natural programming style of those listed for the fun...
christopher/rosetta-code
http://rosettacode.org/wiki/Sum_multiples_of_3_and_5
Sum multiples of 3 and 5
Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
#Maxima
Maxima
sumi(n, inc):= block( [kmax],   /* below n means [1 .. n-1] */ kmax: quotient(n-1, inc), return( ''(ev(sum(inc*k, k, 1, kmax), simpsum)) ) );   sum35(n):= sumi(n, 3) + sumi(n, 5) - sumi(n, 15);   sum35(1000); sum35(10^20);
Give a code snippet in #Maxima Task The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n. Show output for n = 1000. This is is the same as Project Euler problem 1. Extra credit: do this efficiently for n = 1e20 or higher.
christopher/rosetta-code
http://rosettacode.org/wiki/Polymorphic_copy
Polymorphic copy
An object is polymorphic when its specific type may vary. The types a specific value may take, is called class. It is trivial to copy an object if its type is known: int x; int y = x; Here x is not polymorphic, so y is declared of same type (int) as x. But if the specific type of x were unknown, then y could not be d...
#Delphi
Delphi
program PolymorphicCopy;   type T = class function Name:String; virtual; function Clone:T; virtual; end;   S = class(T) function Name:String; override; function Clone:T; override; end;   function T.Name :String; begin Exit('T') end; function T.Clone:T; begin Exit(T.Create)end;   functio...
Give a code snippet in #Delphi An object is polymorphic when its specific type may vary. The types a specific value may take, is called class. It is trivial to copy an object if its type is known: int x; int y = x; Here x is not polymorphic, so y is declared of same type (int) as x. But if the specific type of x wer...
christopher/rosetta-code
http://rosettacode.org/wiki/Inheritance/Multiple
Inheritance/Multiple
Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePhone,   then write a class Camer...
#Wren
Wren
class Camera { construct new() {} snap() { System.print("taking a photo") } }   class Phone { construct new() {} call() { System.print("calling home") } }   class CameraPhone is Camera { construct new(phone) { _phone = phone } // uses composition for the Phone part // inherits Camera's snap() me...
Give a code snippet in #Wren Multiple inheritance allows to specify that one class is a subclass of several other classes. Some languages allow multiple inheritance for arbitrary classes,   others restrict it to interfaces,   some don't allow it at all. Task Write two classes (or interfaces) Camera and MobilePho...
christopher/rosetta-code
http://rosettacode.org/wiki/Multisplit
Multisplit
It is often necessary to split a string into pieces based on several different (potentially multi-character) separator strings, while still retaining the information about which separators were present in the input. This is particularly useful when doing small parsing tasks. The task is to write code to demonstrate ...
#C.2B.2B
C++
#include <iostream> #include <boost/tokenizer.hpp> #include <string>   int main( ) { std::string str( "a!===b=!=c" ) , output ; typedef boost::tokenizer<boost::char_separator<char> > tokenizer ; boost::char_separator<char> separator ( "==" , "!=" ) , sep ( "!" ) ; tokenizer mytok( str , separator ) ; to...
Give a code snippet in #C.2B.2B It is often necessary to split a string into pieces based on several different (potentially multi-character) separator strings, while still retaining the information about which separators were present in the input. This is particularly useful when doing small parsing tasks. The task...
christopher/rosetta-code
http://rosettacode.org/wiki/Sum_of_elements_below_main_diagonal_of_matrix
Sum of elements below main diagonal of matrix
Task Find and display the sum of elements that are below the main diagonal of a matrix. The matrix should be a square matrix. ───   Matrix to be used:   ─── [[1,3,7,8,10], [2,4,16,14,4], [3,1,9,18,11], [12,14,17,18,20], [7,1,3,9,5]]
#Ruby
Ruby
arr = [ [ 1, 3, 7, 8, 10], [ 2, 4, 16, 14, 4], [ 3, 1, 9, 18, 11], [12, 14, 17, 18, 20], [ 7, 1, 3, 9, 5] ] p arr.each_with_index.sum {|row, x| row[0, x].sum}  
Give a code snippet in #Ruby Task Find and display the sum of elements that are below the main diagonal of a matrix. The matrix should be a square matrix. ───   Matrix to be used:   ─── [[1,3,7,8,10], [2,4,16,14,4], [3,1,9,18,11], [12,14,17,18,20], [7,1,3,9,5]]
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...
#Vlang
Vlang
import encoding.hex fn decode(s string) ?[]u8 { return hex.decode(s) }   fn main() { println("${'Char':-7} ${'Unicode':7}\tUTF-8 encoded\tDecoded") for codepoint in [`A`, `ö`, `Ж`, `€`, `𝄞`] { encoded := codepoint.bytes().hex() decoded := decode(encoded)? println("${codepoint:-7} U+...
Give a code snippet in #Vlang 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/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...
#F.23
F#
  // Well I don't do loops. Nigel Galloway: March 17th., 2019. Let me try to explain where the loopy variables are, for the imperatively constrained. // cUL allows me to claim the rather trivial extra credit (commas in the numbers) let cUL=let g=System.Globalization.CultureInfo("en-GB") in (fun (n:uint64)->n.ToString...
Give a code snippet in #F.23 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: ...
christopher/rosetta-code
http://rosettacode.org/wiki/Count_occurrences_of_a_substring
Count occurrences of a substring
Task Create a function,   or show a built-in function,   to count the number of non-overlapping occurrences of a substring inside a string. The function should take two arguments:   the first argument being the string to search,   and   the second a substring to be searched for. It should return an integer cou...
#D
D
void main() { import std.stdio, std.algorithm;   "the three truths".count("th").writeln; "ababababab".count("abab").writeln; }
Give a code snippet in #D Task Create a function,   or show a built-in function,   to count the number of non-overlapping occurrences of a substring inside a string. The function should take two arguments:   the first argument being the string to search,   and   the second a substring to be searched for. It s...
christopher/rosetta-code
http://rosettacode.org/wiki/Runge-Kutta_method
Runge-Kutta method
Given the example Differential equation: y ′ ( t ) = t × y ( t ) {\displaystyle y'(t)=t\times {\sqrt {y(t)}}} With initial condition: t 0 = 0 {\displaystyle t_{0}=0} and y 0 = y ( t 0 ) = y ( 0 ) = 1 {\displaystyle y_{0}=y(t_{0})=y(0)=1} This equation has an exact solution: ...
#ERRE
ERRE
  PROGRAM RUNGE_KUTTA   CONST DELTA_T=0.1   FUNCTION Y1(T,Y) Y1=T*SQR(Y) END FUNCTION   BEGIN Y=1.0 FOR I%=0 TO 100 DO T=I%*DELTA_T   IF T=INT(T) THEN  ! print every tenth ACTUAL=((T^2+4)^2)/16  ! exact solution PRINT("Y(";T;")=";Y;TAB(20);"Error=";ACTUAL-Y) END...
Give a code snippet in #ERRE Given the example Differential equation: y ′ ( t ) = t × y ( t ) {\displaystyle y'(t)=t\times {\sqrt {y(t)}}} With initial condition: t 0 = 0 {\displaystyle t_{0}=0} and y 0 = y ( t 0 ) = y ( 0 ) = 1 {\displaystyle y_{0}=y(t_{0})=y(0)=1} This equ...
christopher/rosetta-code
http://rosettacode.org/wiki/Semordnilap
Semordnilap
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total number of unique semordnilap ...
#XPL0
XPL0
include c:\cxpl\codes; \intrinsic 'code' declarations string 0; \use zero-terminated strings def LF=$0A, CR=$0D, EOF=$1A;   proc RevStr(S); \Reverse order of characters in a string char S; int I, J, T; [J:= 0; while S(J) do J:= J+1; J:= J-1; I:= 0; while I<J do [T:= S(I); S(I):= S(J); ...
Give a code snippet in #XPL0 A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap. Example: lager and regal Task This task does not consider semordnilap phrases, only single words. Using only words from this list, report the total...
christopher/rosetta-code
http://rosettacode.org/wiki/Entropy
Entropy
Task Calculate the Shannon entropy   H   of a given input string. Given the discrete random variable X {\displaystyle X} that is a string of N {\displaystyle N} "symbols" (total characters) consisting of n {\displaystyle n} different characters (n=2 for binary), the Shannon entropy of X in bit...
#ALGOL_W
ALGOL W
begin  % calculates the shannon entropy of a string  %  % strings are fixed length in algol W and the length is part of the  %  % type, so we declare the string parameter to be the longest possible %  % string length (256 characters) and have a second parameter to  %  % spec...
Give a code snippet in #ALGOL_W Task Calculate the Shannon entropy   H   of a given input string. Given the discrete random variable X {\displaystyle X} that is a string of N {\displaystyle N} "symbols" (total characters) consisting of n {\displaystyle n} different characters (n=2 for binary)...
christopher/rosetta-code
http://rosettacode.org/wiki/The_sieve_of_Sundaram
The sieve of Sundaram
The sieve of Eratosthenes: you've been there; done that; have the T-shirt. The sieve of Eratosthenes was ancient history when Euclid was a schoolboy. You are ready for something less than 3000 years old. You are ready for The sieve of Sundaram. Starting with the ordered set of +ve integers, mark every third starting a...
#JavaScript
JavaScript
(() => { "use strict";   // ----------------- SUNDARAM PRIMES -----------------   // sundaramsUpTo :: Int -> [Int] const sundaramsUpTo = n => { const m = Math.floor(n - 1) / 2, excluded = new Set( enumFromTo(1)( Math.floor(Math.sqrt(m /...
Give a code snippet in #JavaScript The sieve of Eratosthenes: you've been there; done that; have the T-shirt. The sieve of Eratosthenes was ancient history when Euclid was a schoolboy. You are ready for something less than 3000 years old. You are ready for The sieve of Sundaram. Starting with the ordered set of +ve i...
christopher/rosetta-code
http://rosettacode.org/wiki/Read_a_specific_line_from_a_file
Read a specific line from a file
Some languages have special semantics for obtaining a known line number from a file. Task Demonstrate how to obtain the contents of a specific line within a file. For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained,   and store it in a variable or in memory   (fo...
#PowerShell
PowerShell
  $file = Get-Content c:\file.txt if ($file.count -lt 7) {Write-Warning "The file is too short!"} else { $file | Where Readcount -eq 7 | set-variable -name Line7 }  
Give a code snippet in #PowerShell Some languages have special semantics for obtaining a known line number from a file. Task Demonstrate how to obtain the contents of a specific line within a file. For the purpose of this task demonstrate how the contents of the seventh line of a file can be obtained,   and store...
christopher/rosetta-code
http://rosettacode.org/wiki/Loops/While
Loops/While
Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Downward for   Loops/For   Loops/For...
#PeopleCode
PeopleCode
  Local string &CRLF; Local number &LoopNumber; &LoopNumber = 1024; &CRLF = Char(10) | Char(13);   While &LoopNumber > 0; WinMessage(&LoopNumber | &CRLF); &LoopNumber = &LoopNumber / 2; End-While;  
Give a code snippet in #PeopleCode Task Start an integer value at   1024. Loop while it is greater than zero. Print the value (with a newline) and divide it by two each time through the loop. Related tasks   Loop over multiple arrays simultaneously   Loops/Break   Loops/Continue   Loops/Do-while   Loops/Do...
christopher/rosetta-code
http://rosettacode.org/wiki/List_rooted_trees
List rooted trees
You came back from grocery shopping.   After putting away all the goods, you are left with a pile of plastic bags, which you want to save for later use, so you take one bag and stuff all the others into it, and throw it under the sink.   In doing so, you realize that there are various ways of nesting the bags, with all...
#jq
jq
# add one bag somewhere def addbag: def sortmap: map(sortmap) | sort; if . == null then [] # one bag else ([[]] + .), (paths as $p | getpath($p) as $x | setpath($p; [[]] + $x) | sortmap # indistinguishability of bags ) end ;   # emit a stream of the distinct r...
Give a code snippet in #jq You came back from grocery shopping.   After putting away all the goods, you are left with a pile of plastic bags, which you want to save for later use, so you take one bag and stuff all the others into it, and throw it under the sink.   In doing so, you realize that there are various ways o...
christopher/rosetta-code
http://rosettacode.org/wiki/Solve_a_Hidato_puzzle
Solve a Hidato puzzle
The task is to write a program which solves Hidato (aka Hidoku) puzzles. The rules are: You are given a grid with some numbers placed in it. The other squares in the grid will be blank. The grid is not necessarily rectangular. The grid may have holes in it. The grid is always connected. The number “1” is always ...
#Wren
Wren
import "/sort" for Sort import "/fmt" for Fmt   var board = [] var given = [] var start = []   var setUp = Fn.new { |input| var nRows = input.count var puzzle = List.filled(nRows, null) for (i in 0...nRows) puzzle[i] = input[i].split(" ") var nCols = puzzle[0].count var list = [] board = List.fi...
Give a code snippet in #Wren The task is to write a program which solves Hidato (aka Hidoku) puzzles. The rules are: You are given a grid with some numbers placed in it. The other squares in the grid will be blank. The grid is not necessarily rectangular. The grid may have holes in it. The grid is always connect...
christopher/rosetta-code
http://rosettacode.org/wiki/Phrase_reversals
Phrase reversals
Task Given a string of space separated words containing the following phrase: rosetta code phrase reversal Reverse the characters of the string. Reverse the characters of each individual word in the string, maintaining original word order within the string. Reverse the order of each word of the string, maintaini...
#Common_Lisp
Common Lisp
  (defun split-string (str) "Split a string into space separated words including spaces" (do* ((lst nil) (i (position-if #'alphanumericp str) (position-if #'alphanumericp str :start j)) (j (when i (position #\Space str :start i)) (when i (position #\Space str :start i))) ) ((null j) (nreverse ...
Give a code snippet in #Common_Lisp Task Given a string of space separated words containing the following phrase: rosetta code phrase reversal Reverse the characters of the string. Reverse the characters of each individual word in the string, maintaining original word order within the string. Reverse the order ...
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 ...
#Joy
Joy
  DEFINE qsort == [small] # termination condition: 0 or 1 element [] # do nothing [uncons [>] split] # pivot and two lists [enconcat] # insert the pivot after the recursion binrec. # recursion on the two lists  
Give a code snippet in #Joy 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/Y_combinator
Y combinator
In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state of a variable and this variable's stat...
#Common_Lisp
Common Lisp
(defun Y (f) ((lambda (g) (funcall g g)) (lambda (g) (funcall f (lambda (&rest a) (apply (funcall g g) a))))))   (defun fac (n) (funcall (Y (lambda (f) (lambda (n) (if (zerop n) 1 (* n (funcall f (1- n))))))) n))   (defun fib (n) (funcall (Y (lambda (f) (lambda ...
Give a code snippet in #Common_Lisp In strict functional programming and the lambda calculus, functions (lambda expressions) don't have state and are only allowed to refer to arguments of enclosing functions. This rules out the usual definition of a recursive function wherein a function is associated with the state o...
christopher/rosetta-code
http://rosettacode.org/wiki/Averages/Pythagorean_means
Averages/Pythagorean means
Task[edit] Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive). Show that A ( x 1 , … , x n ) ≥ G ( x 1 , … , x n ) ≥ H ( x 1 , … , x n ) {\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{1},\ldots ,x_{n})} for this set of p...
#C.23
C#
using System; using System.Collections.Generic; using System.Diagnostics; using System.Linq;   namespace PythMean { static class Program { static void Main(string[] args) { var nums = from n in Enumerable.Range(1, 10) select (double)n;   var a = nums.Average(); var g ...
Give a code snippet in #C.23 Task[edit] Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive). Show that A ( x 1 , … , x n ) ≥ G ( x 1 , … , x n ) ≥ H ( x 1 , … , x n ) {\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{1},\ldot...
christopher/rosetta-code
http://rosettacode.org/wiki/Walk_a_directory/Recursively
Walk a directory/Recursively
Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Walk a directory/Non-recursively   ...
#Factor
Factor
USE: io.directories.search   "." t [ dup ".factor" tail? [ print ] [ drop ] if ] each-file
Give a code snippet in #Factor Task Walk a given directory tree and print files matching a given pattern. Note: This task is for recursive methods.   These tasks should read an entire directory tree, not a single directory. Note: Please be careful when running any code examples found here. Related task   Wal...
christopher/rosetta-code
http://rosettacode.org/wiki/Terminal_control/Cursor_movement
Terminal control/Cursor movement
Task Demonstrate how to achieve movement of the terminal cursor: how to move the cursor one position to the left how to move the cursor one position to the right how to move the cursor up one line (without affecting its horizontal position) how to move the cursor down one line (without affecting its horizontal po...
#ARM_Assembly
ARM Assembly
    /* ARM assembly Raspberry PI */ /* program cursorMove.s */   /* Constantes */ .equ STDOUT, 1 @ Linux output console .equ EXIT, 1 @ Linux syscall .equ WRITE, 4 @ Linux syscall   /* Initialized data */ .data szMessStartPgm: ...
Give a code snippet in #ARM_Assembly Task Demonstrate how to achieve movement of the terminal cursor: how to move the cursor one position to the left how to move the cursor one position to the right how to move the cursor up one line (without affecting its horizontal position) how to move the cursor down one lin...
christopher/rosetta-code
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#bc
bc
scale = 0   /* Format d days after March 21. Assumes March, April, May or June. */ define format(d) { if (d > 80) { print " Jun ", d - 71 } else if (d > 71) { print " Jun 0", d - 71 } else if (d > 49) { print " May ", d - 40 } else if (d > 40) { print " May 0", d - 40 } else if (d > 19) { print...
Give a code snippet in #bc Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years  ...
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,...
#360_Assembly
360 Assembly
* Magic squares of singly even order - 21/04/2021 MAGSQSE CSECT USING MAGSQSE,R13 base register B 72(R15) skip savearea DC 17F'0' savearea SAVE (14,12) save previous context ST R13,4(R15) link backward ...
Give a code snippet in #360_Assembly 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 th...
christopher/rosetta-code
http://rosettacode.org/wiki/Mouse_position
Mouse position
Task Get the current location of the mouse cursor relative to the active window. Please specify if the window may be externally created.
#PureBasic
PureBasic
x = WindowMouseX(#MyWindow) y = WindowMouseY(#MyWindow)
Give a code snippet in #PureBasic Task Get the current location of the mouse cursor relative to the active window. Please specify if the window may be externally created.
christopher/rosetta-code
http://rosettacode.org/wiki/Average_loop_length
Average loop length
Let f be a uniformly-randomly chosen mapping from the numbers 1..N to the numbers 1..N (note: not necessarily a permutation of 1..N; the mapping could produce a number in more than one way or not at all). At some point, the sequence 1, f(1), f(f(1))... will contain a repetition, a number that occurring for the second t...
#Unicon
Unicon
link printf, factors   $define MAX_N 20 $define TIMES 1000000 $define RAND_MAX 2147483647   procedure expected(n) local sum := 0 every i := 1 to n do sum +:= factorial(n) / (n ^ i) / factorial(n - i) return sum end   procedure test(n, times) local i, count := 0, x, bits every i := 0 to times...
Give a code snippet in #Unicon Let f be a uniformly-randomly chosen mapping from the numbers 1..N to the numbers 1..N (note: not necessarily a permutation of 1..N; the mapping could produce a number in more than one way or not at all). At some point, the sequence 1, f(1), f(f(1))... will contain a repetition, a number...
christopher/rosetta-code
http://rosettacode.org/wiki/Hostname
Hostname
Task Find the name of the host on which the routine is running.
#TUSCRIPT
TUSCRIPT
  $$ MODE TUSCRIPT host=HOST ()  
Give a code snippet in #TUSCRIPT Task Find the name of the host on which the routine is running.
christopher/rosetta-code
http://rosettacode.org/wiki/Tree_from_nesting_levels
Tree from nesting levels
Given a flat list of integers greater than zero, representing object nesting levels, e.g. [1, 2, 4], generate a tree formed from nested lists of those nesting level integers where: Every int appears, in order, at its depth of nesting. If the next level int is greater than the previous then it appears in a sub-list o...
#Perl
Perl
#!/usr/bin/perl   use strict; use warnings; use Data::Dump qw(dd pp);   my @tests = ( [] ,[1, 2, 4] ,[3, 1, 3, 1] ,[1, 2, 3, 1] ,[3, 2, 1, 3] ,[3, 3, 3, 1, 1, 3, 3, 3] );   for my $before ( @tests ) { dd { before => $before }; local $_ = (pp $before) =~ s/\d+/ '['x($&-1) . $& . ']'x($&-1) /ger; ...
Give a code snippet in #Perl Given a flat list of integers greater than zero, representing object nesting levels, e.g. [1, 2, 4], generate a tree formed from nested lists of those nesting level integers where: Every int appears, in order, at its depth of nesting. If the next level int is greater than the previous t...
christopher/rosetta-code
http://rosettacode.org/wiki/Window_management
Window management
Treat windows or at least window identities as first class objects. Store window identities in variables, compare them for equality. Provide examples of performing some of the following: hide, show, close, minimize, maximize, move,     and resize a window. The window of interest may or may not have b...
#Ring
Ring
    Load "guilib.ring"   /* +-------------------------------------------------------------------------- + Program Name : ScreenDrawOnReSize.ring + Date  : 2016.06.16 + Author  : Bert Mariani + Purpose  : Re-Draw Chart after ReSize or move +------------------------------...
Give a code snippet in #Ring Treat windows or at least window identities as first class objects. Store window identities in variables, compare them for equality. Provide examples of performing some of the following: hide, show, close, minimize, maximize, move,     and resize a window. The window of ...
christopher/rosetta-code
http://rosettacode.org/wiki/Hash_from_two_arrays
Hash from two arrays
Task Using two Arrays of equal length, create a Hash object where the elements from one array (the keys) are linked to the elements of the other (the values) Related task   Associative arrays/Creation
#Lua
Lua
function(keys,values) local t = {} for i=1, #keys do t[keys[i]] = values[i] end end
Give a code snippet in #Lua Task Using two Arrays of equal length, create a Hash object where the elements from one array (the keys) are linked to the elements of the other (the values) Related task   Associative arrays/Creation
christopher/rosetta-code
http://rosettacode.org/wiki/Generic_swap
Generic swap
Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity. If variables are typed in t...
#DCL
DCL
$ a1 = 123 $ a2 = "hello" $ show symbol a* $ gosub swap $ show symbol a* $ exit $ $ swap: $ t = a1 $ a1 = a2 $ a2 = t $ return
Give a code snippet in #DCL Task Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types. If your solution language is statically typed please describe the way your language provides genericity....
christopher/rosetta-code
http://rosettacode.org/wiki/Langton%27s_ant
Langton's ant
Langton's ant is a cellular automaton that models an ant sitting on a plane of cells, all of which are white initially, the ant facing in one of four directions. Each cell can either be black or white. The ant moves according to the color of the cell it is currently sitting in, with the following rules:   If the ce...
#LOLCODE
LOLCODE
HAI 1.3   I HAS A plane ITZ A BUKKIT IM IN YR init UPPIN YR i TIL BOTH SAEM i AN 10000 plane HAS A SRS i ITZ FAIL IM OUTTA YR init   I HAS A x ITZ 50, I HAS A y ITZ 50 I HAS A dir ITZ 0, I HAS A pos, I HAS A cell   BTW, WE PURRTIND WE HAS A 2D STRUKSHUR FUR EZ AKSESS IM IN YR walker pos R SUM OF PRODUKT OF y AN...
Give a code snippet in #LOLCODE Langton's ant is a cellular automaton that models an ant sitting on a plane of cells, all of which are white initially, the ant facing in one of four directions. Each cell can either be black or white. The ant moves according to the color of the cell it is currently sitting in, with t...
christopher/rosetta-code
http://rosettacode.org/wiki/Constrained_genericity
Constrained genericity
Constrained genericity or bounded quantification means that a parametrized type or function (see parametric polymorphism) can only be instantiated on types fulfilling some conditions, even if those conditions are not used in that function. Say a type is called "eatable" if you can call the function eat on it. Write a ...
#Objective-C
Objective-C
@protocol Eatable - (void)eat; @end
Give a code snippet in #Objective-C Constrained genericity or bounded quantification means that a parametrized type or function (see parametric polymorphism) can only be instantiated on types fulfilling some conditions, even if those conditions are not used in that function. Say a type is called "eatable" if you can ...
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...
#Phix
Phix
with javascript_semantics function one_of_n(integer n) integer line_num = 1 for i=2 to n do if rnd()<1/i then line_num = i end if end for return line_num end function sequence counts = repeat(0,10) for i=1 to 1000000 do integer cdx = one_of_n(10) counts[cdx] += 1 e...
Give a code snippet in #Phix 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...
christopher/rosetta-code
http://rosettacode.org/wiki/Mastermind
Mastermind
Create a simple version of the board game:   Mastermind. It must be possible to:   choose the number of colors will be used in the game (2 - 20)   choose the color code length (4 - 10)   choose the maximum number of guesses the player has (7 - 20)   choose whether or not colors may be repeated in the code The (...
#C.2B.2B
C++
#include <iostream> #include <algorithm> #include <ctime> #include <string> #include <vector>   typedef std::vector<char> vecChar;   class master { public: master( size_t code_len, size_t clr_count, size_t guess_count, bool rpt ) { std::string color = "ABCDEFGHIJKLMNOPQRST";   if( code_len < 4 ) cod...
Give a code snippet in #C.2B.2B Create a simple version of the board game:   Mastermind. It must be possible to:   choose the number of colors will be used in the game (2 - 20)   choose the color code length (4 - 10)   choose the maximum number of guesses the player has (7 - 20)   choose whether or not colors ma...
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 ...
#TorqueScript
TorqueScript
function findIn(%haystack,%needles) { %hc = getWordCount(%haystack); %nc = getWordCount(%needles);   for(%i=0;%i<%nc;%i++) { %nword = getWord(%needles,%i); %index[%nword] = -1; }   for(%i=0;%i<%hc;%i++) { %hword = getWord(%haystack,%i);   for(%j=0;%j<%nc;%j++) { %nword = getWord(%needles,%j);   ...
Give a code snippet in #TorqueScript 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 ne...
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 ...
#Elena
Elena
import extensions;   singleton AksTest { static long[] c := new long[](100);   coef(int n) { int i := 0; int j := 0;   if ((n < 0) || (n > 63)) { AbortException.raise() }; // gracefully deal with range issue   c[i] := 1l; for (int i := 0, i < n, i += 1) { ...
Give a code snippet in #Elena 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 ...
christopher/rosetta-code
http://rosettacode.org/wiki/Primality_by_trial_division
Primality by trial division
Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops are allowed. Related tasks ...
#CLU
CLU
isqrt = proc (s: int) returns (int) x0: int := s/2 if x0=0 then return(s) end x1: int := (x0 + s/x0)/2 while x1 < x0 do x0 := x1 x1 := (x0 + s/x0)/2 end return(x0) end isqrt   prime = proc (n: int) returns (bool) if n<=2 then return(n=2) end if n//2=0 then return(false) e...
Give a code snippet in #CLU Task Write a boolean function that tells whether a given integer is prime. Remember that   1   and all non-positive numbers are not prime. Use trial division. Even numbers greater than   2   may be eliminated right away. A loop from   3   to   √ n    will suffice,   but other loops a...
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...
#C.23
C#
using System; public class Program { public static void Main() { for (int p = 2; p <= 7; p+=2) { for (int s = 1; s <= 7; s++) { int f = 12 - p - s; if (s >= f) break; if (f > 7) continue; if (s == p || f == p) continue; //not even n...
Give a code snippet in #C.23 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 (dif...
christopher/rosetta-code
http://rosettacode.org/wiki/Brazilian_numbers
Brazilian numbers
Brazilian numbers are so called as they were first formally presented at the 1994 math Olympiad Olimpiada Iberoamericana de Matematica in Fortaleza, Brazil. Brazilian numbers are defined as: The set of positive integer numbers where each number N has at least one natural number B where 1 < B < N-1 where the represent...
#Phix
Phix
with javascript_semantics function same_digits(integer n, b) integer f = remainder(n,b) n = floor(n/b) while n>0 do if remainder(n,b)!=f then return false end if n = floor(n/b) end while return true end function function is_brazilian(integer n) if n>=7 then if remainder...
Give a code snippet in #Phix Brazilian numbers are so called as they were first formally presented at the 1994 math Olympiad Olimpiada Iberoamericana de Matematica in Fortaleza, Brazil. Brazilian numbers are defined as: The set of positive integer numbers where each number N has at least one natural number B where 1...
christopher/rosetta-code
http://rosettacode.org/wiki/Sort_three_variables
Sort three variables
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 ...
#Ksh
Ksh
  #!/bin/ksh   # Sort three variables that may contain any value (numbers and/or literals)   # # Variables: # xl='lions, tigers, and' yl='bears, oh my!' zl='(from the "Wizard of OZ")'   typeset -i xn=77444 typeset -F yn=-12.0 typeset -i zn=0   # # Functions: #   # # Function _intoarray(x, y, z, arr) - put 3 variables i...
Give a code snippet in #Ksh 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/Send_email
Send email
Task Write a function to send an email. The function should have parameters for setting From, To and Cc addresses; the Subject, and the message text, and optionally fields for the server name and login details. If appropriate, explain what notifications of problems/success are given. Solutions using libraries or f...
#Nim
Nim
import smtp   proc sendMail(fromAddr: string; toAddrs, ccAddrs: seq[string]; subject, message, login, password: string; server = "smtp.gmail.com"; port = Port 465; ssl = true) = let msg = createMessage(subject, message, toAddrs, ccAddrs) let session = newSmtp(useSsl = ssl, debug = true) ...
Give a code snippet in #Nim Task Write a function to send an email. The function should have parameters for setting From, To and Cc addresses; the Subject, and the message text, and optionally fields for the server name and login details. If appropriate, explain what notifications of problems/success are given. S...
christopher/rosetta-code
http://rosettacode.org/wiki/Create_an_HTML_table
Create an HTML table
Create an HTML table. The table body should have at least three rows of three columns. Each of these three columns should be labelled "X", "Y", and "Z". An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled with sequential row numbers. The...
#Peloton
Peloton
<@ SDCLIT> <@ DTBLIT> <@ DTRLITLIT> <@ DTDLITLIT>|[style]background-color:white</@> <@ DTD>X</@> <@ DTD>Y</@> <@ DTD>Z</@>|[style]width:100%; background-color:brown;color:white; text-align:center</@> <@ ITEFORLIT>10| <@ DTRLITCAP> <@ DTDPOSFORLIT>...|[style]background-color:Brown; color:white; te...
Give a code snippet in #Peloton Create an HTML table. The table body should have at least three rows of three columns. Each of these three columns should be labelled "X", "Y", and "Z". An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled w...
christopher/rosetta-code
http://rosettacode.org/wiki/Continued_fraction
Continued fraction
continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to write a program which generates su...
#NetRexx
NetRexx
/* REXX *************************************************************** * Derived from REXX ... Derived from PL/I with a little "massage" * SQRT2= 1.41421356237309505 <- PL/I Result * 1.41421356237309504880168872421 <- NetRexx Result 30 digits * NAPIER= 2.71828182845904524 * 2.71828182845...
Give a code snippet in #NetRexx continued fraction Mathworld a 0 + b 1 a 1 + b 2 a 2 + b 3 a 3 + ⋱ {\displaystyle a_{0}+{\cfrac {b_{1}}{a_{1}+{\cfrac {b_{2}}{a_{2}+{\cfrac {b_{3}}{a_{3}+\ddots }}}}}}} The task is to w...
christopher/rosetta-code
http://rosettacode.org/wiki/Galton_box_animation
Galton box animation
Example of a Galton Box at the end of animation. A   Galton device   Sir Francis Galton's device   is also known as a   bean machine,   a   Galton Board,   or a   quincunx. Description of operation In a Galton box, there are a set of pins arranged in a triangular pattern.   A number of balls are dropped so that ...
#Ruby
Ruby
$rows_of_pins = 12 $width = $rows_of_pins * 10 + ($rows_of_pins+1)*14   Shoes.app( :width => $width + 14, :title => "Galton Box" ) do @bins = Array.new($rows_of_pins+1, 0)   @x_coords = Array.new($rows_of_pins) {Array.new} @y_coords = Array.new($rows_of_pins) stack(:width => $width) do stroke gray ...
Give a code snippet in #Ruby Example of a Galton Box at the end of animation. A   Galton device   Sir Francis Galton's device   is also known as a   bean machine,   a   Galton Board,   or a   quincunx. Description of operation In a Galton box, there are a set of pins arranged in a triangular pattern.   A number...
christopher/rosetta-code
http://rosettacode.org/wiki/Bitmap/Read_a_PPM_file
Bitmap/Read a PPM file
Using the data storage type defined on this page for raster images, read an image from a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.) Task: Use write ppm file solution and grayscale image solution with this one in order to convert a color image to grayscale one.
#Nim
Nim
import strutils import bitmap import streams   type FormatError = object of CatchableError   # States used to parse the header. type State = enum waitingMagic, waitingWidth, waitingHeight, waitingColors   #---------------------------------------------------------------------------------------------------   iterator tok...
Give a code snippet in #Nim Using the data storage type defined on this page for raster images, read an image from a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.) Task: Use write ppm file solution and grayscale image solution with this one in order to convert a color image to grayscal...
christopher/rosetta-code
http://rosettacode.org/wiki/Environment_variables
Environment variables
Task Show how to get one of your process's environment variables. The available variables vary by system;   some of the common ones available on Unix include:   PATH   HOME   USER
#Swift
Swift
print("USER: \(ProcessInfo.processInfo.environment["USER"] ?? "Not set")") print("PATH: \(ProcessInfo.processInfo.environment["PATH"] ?? "Not set")")
Give a code snippet in #Swift Task Show how to get one of your process's environment variables. The available variables vary by system;   some of the common ones available on Unix include:   PATH   HOME   USER
christopher/rosetta-code
http://rosettacode.org/wiki/Constrained_random_points_on_a_circle
Constrained random points on a circle
Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" circle. The actual number of point...
#Clojure
Clojure
(ns rosettacode.circle-random-points (:import [java.awt Color Graphics Dimension] [javax.swing JFrame JPanel]))   (let [points (->> (for [x (range -15 16), y (range -15 16) :when (<= 10 (Math/hypot x y) 15)] [(+ x 15) (+ y 15)]) shuffle (take 100))] (doto (JFrame.) (.add (doto (proxy...
Give a code snippet in #Clojure Task Generate 100 <x,y> coordinate pairs such that x and y are integers sampled from the uniform distribution with the condition that 10 ≤ x 2 + y 2 ≤ 15 {\displaystyle 10\leq {\sqrt {x^{2}+y^{2}}}\leq 15} . Then display/plot them. The outcome should be a "fuzzy" c...
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).
#Befunge
Befunge
"| "+,@
Give a code snippet in #Befunge Task Display an extended (non ASCII) character onto the terminal. Specifically, display a   £   (GBP currency sign).
christopher/rosetta-code
http://rosettacode.org/wiki/Balanced_brackets
Balanced brackets
Task: Generate a string with   N   opening brackets   [   and with   N   closing brackets   ],   in some arbitrary order. Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nest. Examples (empty) ...
#Lua
Lua
  function isBalanced(s) --Lua pattern matching has a 'balanced' pattern that matches sets of balanced characters. --Any two characters can be used. return s:gsub('%b[]','')=='' and true or false end   function randomString() math.randomseed(os.time()) math.random()math.random()math.random()math.random() lo...
Give a code snippet in #Lua Task: Generate a string with   N   opening brackets   [   and with   N   closing brackets   ],   in some arbitrary order. Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nes...
christopher/rosetta-code
http://rosettacode.org/wiki/Superpermutation_minimisation
Superpermutation minimisation
A superpermutation of N different characters is a string consisting of an arrangement of multiple copies of those N different characters in which every permutation of those characters can be found as a substring. For example, representing the characters as A..Z, using N=2 we choose to use the first two characters 'AB'...
#Java
Java
import static java.util.stream.IntStream.rangeClosed;   public class Test { final static int nMax = 12;   static char[] superperm; static int pos; static int[] count = new int[nMax];   static int factSum(int n) { return rangeClosed(1, n) .map(m -> rangeClosed(1, m).reduce(1, ...
Give a code snippet in #Java A superpermutation of N different characters is a string consisting of an arrangement of multiple copies of those N different characters in which every permutation of those characters can be found as a substring. For example, representing the characters as A..Z, using N=2 we choose to use...
christopher/rosetta-code
http://rosettacode.org/wiki/Handle_a_signal
Handle a signal
Most operating systems provide interrupt facilities, sometimes called signals either generated by the user or as a result of program failure or reaching a limit like file space. Unhandled signals generally terminate a program in a disorderly manner. Signal handlers are created so that the program behaves in a well-defi...
#Liberty_BASIC
Liberty BASIC
  nomainwin WindowHeight=DisplayHeight open "Handle a signal" for graphics as #1 #1 "trapclose [quit]" #1 "down;setfocus;place 10 20" #1 "\Press CTRL + C to stop." #1 "when characterInput [keyPressed]" start=time$("ms") timer 500, [doPrint] wait [quit] close #1:end   [doPrint] if sigInt then timer 0 #1 "\Seco...
Give a code snippet in #Liberty_BASIC Most operating systems provide interrupt facilities, sometimes called signals either generated by the user or as a result of program failure or reaching a limit like file space. Unhandled signals generally terminate a program in a disorderly manner. Signal handlers are created so ...
christopher/rosetta-code
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were s...
#Phix
Phix
function tokenize(string s, integer sep, integer esc) sequence ret = {} string word = "" integer skip = 0 if length(s)!=0 then for i=1 to length(s) do integer si = s[i] if skip then word &= si skip = 0 elsif si=esc then sk...
Give a code snippet in #Phix Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for split...
christopher/rosetta-code
http://rosettacode.org/wiki/Pragmatic_directives
Pragmatic directives
Pragmatic directives cause the language to operate in a specific manner,   allowing support for operational variances within the program code   (possibly by the loading of specific or alternative modules). Task List any pragmatic directives supported by the language,   and demonstrate how to activate and deactivate...
#PowerShell
PowerShell
  #Requires -Version <N>[.<n>] #Requires –PSSnapin <PSSnapin-Name> [-Version <N>[.<n>]] #Requires -Modules { <Module-Name> | <Hashtable> } #Requires –ShellId <ShellId> #Requires -RunAsAdministrator  
Give a code snippet in #PowerShell Pragmatic directives cause the language to operate in a specific manner,   allowing support for operational variances within the program code   (possibly by the loading of specific or alternative modules). Task List any pragmatic directives supported by the language,   and demons...
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.
#zkl
zkl
const { [1..10].reduce('*).println(" parse time") }   #fcn fact(N) { [1..N].reduce('*).println(" tokenize time"); ""} // paste output of fact into source #tokenize fact(10)   println("compiled program running.");
Give a code snippet in #zkl 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/Shell_one-liner
Shell one-liner
Task Show how to specify and execute a short program in the language from a command shell, where the input to the command shell is only one line in length. Avoid depending on the particular shell or operating system used as much as is reasonable; if the language has notable implementations which have different comman...
#CMake
CMake
echo 'message(STATUS "Goodbye, World!")' | cmake -P /dev/stdin
Give a code snippet in #CMake Task Show how to specify and execute a short program in the language from a command shell, where the input to the command shell is only one line in length. Avoid depending on the particular shell or operating system used as much as is reasonable; if the language has notable implementati...
christopher/rosetta-code
http://rosettacode.org/wiki/Logical_operations
Logical 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 |...
#Dc
Dc
[ 1 q ] sT   [ 0=T 0 ] s! [ l! x S@ l! x L@ + l! x ] s& [ l! x S@ l! x L@ * l! x ] s|   [ 48 + P ] s.   [ Sb Sa la l. x [ ] P lb l. x [ ] P la lb l& x l. x [ ] P la Lb l| x l. x [ ] P La l! x l. x A P ] sF   [a b a&b a|b !a] P A P 0 0 lF x 0 1 lF x 1 0 lF x 1 1 lF x
Give a code snippet in #Dc 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 Con...
christopher/rosetta-code
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort
Sorting algorithms/Sleep 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 ...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
SleepSort = RunScheduledTask[Print@#, {#, 1}] & /@ # &; SleepSort@{1, 9, 8, 7, 6, 5, 3, 4, 5, 2, 0};
Give a code snippet in #Mathematica.2FWolfram_Language 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 |...
christopher/rosetta-code
http://rosettacode.org/wiki/Least_common_multiple
Least common multiple
Least common multiple You are encouraged to solve this task according to the task description, using any language you may know. Task Compute the   least common multiple   (LCM)   of two integers. Given   m   and   n,   the least common multiple is the smallest positive integer that has both   m   and   n   as factor...
#PicoLisp
PicoLisp
(de lcm (A B) (abs (*/ A B (gcd A B))) )
Give a code snippet in #PicoLisp Least common multiple You are encouraged to solve this task according to the task description, using any language you may know. Task Compute the   least common multiple   (LCM)   of two integers. Given   m   and   n,   the least common multiple is the smallest positive integer that ...
christopher/rosetta-code
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#TUSCRIPT
TUSCRIPT
  $$ MODE TUSCRIPT SET DATEN = REQUEST ("http://www.rosettacode.org") *{daten}  
Give a code snippet in #TUSCRIPT Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
christopher/rosetta-code