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http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#C
C
#include <stdio.h> #include <stdarg.h>   void varstrings(int count, ...) /* the ellipsis indicates variable arguments */ { va_list args; va_start(args, count); while (count--) puts(va_arg(args, const char *)); va_end(args); }   varstrings(5, "Mary", "had", "a", "little", "lamb");
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#C.23
C#
using System;   class Program { static void Main(string[] args) { PrintAll("test", "rosetta code", 123, 5.6); }   static void PrintAll(params object[] varargs) { foreach (var i in varargs) { Console.WriteLine(i); } } }
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#BASIC
BASIC
10 REM this only works with strings 20 PRINT LEN(variable$)
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#BASIC256
BASIC256
i = 1 #Integer f = 1.0 #Float s$ = "cad" #String dim a(99) #Array A = {1, 2, 3} #Anonymous array m = {"key" -> 1} #Map   print typeof(i) # 1 print typeof(f) # 2 print typeof(s$) # 3 print typeof(A) # 4 print typeof(m) # 6
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#BBC_BASIC
BBC BASIC
DIM bstruct{b&} DIM istruct{i%} DIM fstruct{f} DIM dstruct{d#} DIM sstruct{s$}   PRINT "Size of b& is ";DIM(bstruct{}) PRINT "Size of i% is ";DIM(istruct{}) PRINT "Size of f is ";DIM(fstruct{}) PRINT "Size of d# is ";DIM(dstruct{}) PRINT "Size of s$ is ";DIM(...
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#C
C
printf("An int contains %u bytes.\n", sizeof(int));
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Go
Go
package main   import "fmt"   type vector []float64   func (v vector) add(v2 vector) vector { r := make([]float64, len(v)) for i, vi := range v { r[i] = vi + v2[i] } return r }   func (v vector) sub(v2 vector) vector { r := make([]float64, len(v)) for i, vi := range v { r[i] = vi...
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#Tcl
Tcl
% proc format_trace {fmt _var el op} {upvar 1 $_var v; set v [format $fmt $v]}   % trace var foo w {format_trace %10s} % puts "/[set foo bar]/" / bar/   % trace var grill w {format_trace %-10s} % puts "/[set grill bar]/" /bar /
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#TXR
TXR
(make-buf 8 0 4096)
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#Ursala
Ursala
p = mpfr..pi 200 # 200 bits of precision   x = mpfr..grow(1.0E+0,1000) # 160 default precision, grown to 1160   y = mpfr..shrink(1.0+0,40) # 160 default shrunk to 120   z = mpfr..add(p,y) # inherits 200 bits of precision   a = # 180 bits (not the default 160) because of more digits in t...
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#Vlang
Vlang
fn main() { b := true i := 5 // default type is i32 r := '5' f := 5.0 // default type is float64 println("b: ${sizeof(b)} bytes") println("i: ${sizeof(i)} bytes") println("r: ${sizeof(r)} bytes") println("f: ${sizeof(f)} bytes") i_min := i8(5) r_min := `5` f_min := f32(5.0...
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#Wren
Wren
// create a list with 10 elements all initialized to zero var l = List.filled(10, 0) // give them different values and print them for (i in 0..9) l[i] = i System.print(l) // add another element to the list dynamically and print it again l.add(10) System.print(l)
http://rosettacode.org/wiki/Voronoi_diagram
Voronoi diagram
A Voronoi diagram is a diagram consisting of a number of sites. Each Voronoi site s also has a Voronoi cell consisting of all points closest to s. Task Demonstrate how to generate and display a Voroni diagram. See algo K-means++ clustering.
#XPL0
XPL0
include c:\cxpl\codes; \intrinsic 'code' declarations   def N = 15; \number of sites int SiteX(N), SiteY(N), \coordinates of sites Dist2, MinDist2, MinI, \distance squared, and minimums X, Y, I; [SetVid($13); \set 320x200x8 graphics for I:= 0 to N-...
http://rosettacode.org/wiki/Voronoi_diagram
Voronoi diagram
A Voronoi diagram is a diagram consisting of a number of sites. Each Voronoi site s also has a Voronoi cell consisting of all points closest to s. Task Demonstrate how to generate and display a Voroni diagram. See algo K-means++ clustering.
#Yabasic
Yabasic
  clear screen   sites = 200 xEdge = 600 yEdge = 400   open window xEdge, yEdge   dim townX(sites), townY(sites), col$(sites)   for i =1 to sites townX(i) =int(xEdge *ran(1)) townY(i) =int(yEdge *ran(1)) col$(i) = str$(int(256 * ran(1))) + ", " + str$(int(256 * ran(1))) + ", " + str$(int(256 * ran(1))) ...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#REXX
REXX
/*REXX program performs a chi─squared test to verify a given distribution is uniform. */ numeric digits length( pi() ) - length(.) /*enough decimal digs for calculations.*/ @.=; @.1= 199809 200665 199607 200270 199649 @.2= 52257...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Julia
Julia
  →(a::Char, b::Char, ± = +) = 'A'+((a-'A')±(b-'A')+26)%26 ←(a::Char, b::Char) = →(a,b,-)   cleanup(str) = filter(a-> a in 'A':'Z', collect(uppercase.(str))) match_length(word, len) = repeat(word,len)[1:len]   function →(message::String, codeword::String, ↔ = →) plaintext = cleanup(message) key = match_length(c...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Prolog
Prolog
% direction may be horizontal/vertical/list display_tree(Direction) :- sformat(A, 'Display tree ~w', [Direction]), new(D, window(A)), send(D, size, size(350,200)), new(T, tree(text('Root'))), send(T, neighbour_gap, 10), new(S1, node(text('Child1'))), new(S2, node(text('Child2'))), send_list(T, son,[S1,S2]), ne...
http://rosettacode.org/wiki/Walk_a_directory/Non-recursively
Walk a directory/Non-recursively
Task Walk a given directory and print the names of files matching a given pattern. (How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?) Note: This task is for non-recursive methods.   These tasks should read a single directory, not an entire directory tree. ...
#Visual_Basic_.NET
Visual Basic .NET
'Using the OS pattern matching For Each file In IO.Directory.GetFiles("\temp", "*.txt") Console.WriteLine(file) Next   'Using VB's pattern matching and LINQ For Each file In (From name In IO.Directory.GetFiles("\temp") Where name Like "*.txt") Console.WriteLine(file) Next   'Using VB's pattern matching and dot-nota...
http://rosettacode.org/wiki/Walk_a_directory/Non-recursively
Walk a directory/Non-recursively
Task Walk a given directory and print the names of files matching a given pattern. (How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?) Note: This task is for non-recursive methods.   These tasks should read a single directory, not an entire directory tree. ...
#Wren
Wren
import "io" for Directory import "/pattern" for Pattern   var walk = Fn.new { |dir, pattern| if (!Directory.exists(dir)) Fiber.abort("Directory does not exist.") var files = Directory.list(dir) return files.where { |f| pattern.isMatch(f) } }   // get all C header files beginning with 'a' or 'b' var p = Patt...
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   ...
#PHP
PHP
function findFiles($dir = '.', $pattern = '/./'){ $prefix = $dir . '/'; $dir = dir($dir); while (false !== ($file = $dir->read())){ if ($file === '.' || $file === '..') continue; $file = $prefix . $file; if (is_dir($file)) findFiles($file, $pattern); if (preg_match($pattern, $file)){ echo $f...
http://rosettacode.org/wiki/Water_collected_between_towers
Water collected between towers
Task In a two-dimensional world, we begin with any bar-chart (or row of close-packed 'towers', each of unit width), and then it rains, completely filling all convex enclosures in the chart with water. 9 ██ 9 ██ 8 ██ 8 ██ 7 ██ ...
#Racket
Racket
#lang racket/base (require racket/match)   (define (water-collected-between-towers towers) (define (build-tallest-left/rev-list t mx/l rv) (match t [(list) rv] [(cons a d) (define new-mx/l (max a mx/l)) (build-tallest-left/rev-list d new-mx/l (cons mx/l rv))]))   (define (collect-from-...
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#APL
APL
dot ← +.× cross ← 1⌽(⊣×1⌽⊢)-⊢×1⌽⊣
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#Run_BASIC
Run BASIC
s$ = "#########################" dim num(100) for i = 1 to 1000 n = (rnd(1) * 10) + 1 num(n) = num(n) + 1 next i   for i = 1 to 10 print using("###",i);" "; using("#####",num(i));" ";left$(s$,num(i) / 5) next i
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#Scala
Scala
object DistrubCheck1 extends App {   private def distCheck(f: () => Int, nRepeats: Int, delta: Double): Unit = { val counts = scala.collection.mutable.Map[Int, Int]()   for (_ <- 0 until nRepeats) counts.updateWith(f()) { case Some(count) => Some(count + 1) case None => Some(1) }  ...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#AWK
AWK
  # syntax: GAWK -f VARIABLE_DECLARATION_RESET.AWK BEGIN { n = split("1,2,2,3,4,4,5",arr,",") for (i=1; i<=n; i++) { curr = arr[i] if (i > 1 && prev == curr) { printf("%s\n",i) } prev = curr } exit(0) }  
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#C
C
#include <stdio.h>   int main() { int i, gprev = 0; int s[7] = {1, 2, 2, 3, 4, 4, 5};   /* There is no output as 'prev' is created anew each time around the loop and set explicitly to zero. */ for (i = 0; i < 7; ++i) { // for (int i = 0, prev; i < 7; ++i) { // as below, see note int curr...
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#11l
11l
Int a
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#11l
11l
F van_eck(c) [Int] r V n = 0 V seen = [0] V val = 0 L r.append(val) I r.len == c R r I val C seen[1..] val = seen.index(val, 1) E val = 0 seen.insert(0, val) n++   print(‘Van Eck: first 10 terms: ’van_eck(10)) print(‘Van Eck: terms 991 - 10...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Julia
Julia
using Printf   mutable struct VLQ quant::Vector{UInt8} end   function VLQ(n::T) where T <: Integer quant = UInt8.(digits(n, 128)) @inbounds for i in 2:length(quant) quant[i] |= 0x80 end VLQ(reverse(quant)) end   import Base.UInt64 function Base.UInt64(vlq::VLQ) quant = reverse(vlq.quant) n = shi...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Kotlin
Kotlin
// version 1.0.6   fun Int.toOctets(): ByteArray { var s = Integer.toBinaryString(this) val r = s.length % 7 var z = s.length / 7 if (r > 0) { z++ s = s.padStart(z * 7, '0') } s = Array(z) { "1" + s.slice(it * 7 until (it + 1) * 7) }.joinToString("") s = s.take(s.length - 8) ...
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#C.2B.2B
C++
#include <iostream>   template<typename T> void print(T const& t) { std::cout << t; }   template<typename First, typename ... Rest> void print(First const& first, Rest const& ... rest) { std::cout << first; print(rest ...); }   int main() { int i = 10; std::string s = "Hello world"; print("i = ", i, " and...
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#C.23
C#
  class Program { static void Main(string[] args) { int i = sizeof(int); Console.WriteLine(i); Console.ReadLine(); } }  
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#C.2B.2B
C++
#include <cstdlib> std::size_t intsize = sizeof(int);
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#COBOL
COBOL
  identification division. program-id. variable-size-get.   environment division. configuration section. repository. function all intrinsic.   data division. working-storage section. 01 bc-len constant as length of binary-char. 01 fd-34...
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Groovy
Groovy
import groovy.transform.EqualsAndHashCode   @EqualsAndHashCode class Vector { private List<Number> elements Vector(List<Number> e ) { if (!e) throw new IllegalArgumentException("A Vector must have at least one element.") if (!e.every { it instanceof Number }) throw new IllegalArgumentException("...
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#XPL0
XPL0
include c:\cxpl\codes; \intrinsic 'code' declarations string 0; \use zero-terminated strings char S, A(1), \sets up an array containing one byte B(0); \sets up an array containing no bytes int I; [S:= ""; \a zero-length (null) string A:= Reserve(1); ...
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#Z80_Assembly
Z80 Assembly
MyByte: byte 0 ;most assemblers will also accept DB or DFB MyWord: word 0 ;most assemblers will also accept DW or DFW MyDouble: dd 0
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#zkl
zkl
10 DIM a$(10): REM This array will be 10 characters long 20 DIM b(10): REM this will hold a set of numbers. The fixed number of bytes per number is implementation specific 30 LET c=5: REM this is a single numerical value of fixed size
http://rosettacode.org/wiki/Variable_size/Set
Variable size/Set
Task Demonstrate how to specify the minimum size of a variable or a data type.
#ZX_Spectrum_Basic
ZX Spectrum Basic
10 DIM a$(10): REM This array will be 10 characters long 20 DIM b(10): REM this will hold a set of numbers. The fixed number of bytes per number is implementation specific 30 LET c=5: REM this is a single numerical value of fixed size
http://rosettacode.org/wiki/Voronoi_diagram
Voronoi diagram
A Voronoi diagram is a diagram consisting of a number of sites. Each Voronoi site s also has a Voronoi cell consisting of all points closest to s. Task Demonstrate how to generate and display a Voroni diagram. See algo K-means++ clustering.
#zkl
zkl
fcn generate_voronoi_diagram(width,height,num_cells){ image,imgx,imgy:=PPM(width,height),width,height; nx:=num_cells.pump(List,(0).random.fp(imgx)); ny:=num_cells.pump(List,(0).random.fp(imgy)); nr:=num_cells.pump(List,(0).random.fp(256)); // red ng:=num_cells.pump(List,(0).random.fp(256)); // blue ...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#Ruby
Ruby
def gammaInc_Q(a, x) a1, a2 = a-1, a-2 f0 = lambda {|t| t**a1 * Math.exp(-t)} df0 = lambda {|t| (a1-t) * t**a2 * Math.exp(-t)}   y = a1 y += 0.3 while f0[y]*(x-y) > 2.0e-8 and y < x y = x if y > x   h = 3.0e-4 n = (y/h).to_i h = y/n hh = 0.5 * h sum = 0 (n-1).step(0, -1) do |j| t = h * j ...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Kotlin
Kotlin
// version 1.1.3   fun vigenere(text: String, key: String, encrypt: Boolean = true): String { val t = if (encrypt) text.toUpperCase() else text val sb = StringBuilder() var ki = 0 for (c in t) { if (c !in 'A'..'Z') continue val ci = if (encrypt) (c.toInt() + key[ki].toInt() -...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Python
Python
Python 3.2.3 (default, May 3 2012, 15:54:42) [GCC 4.6.3] on linux2 Type "copyright", "credits" or "license()" for more information. >>> help('pprint.pprint') Help on function pprint in pprint:   pprint.pprint = pprint(object, stream=None, indent=1, width=80, depth=None) Pretty-print a Python object to a stream [d...
http://rosettacode.org/wiki/Walk_a_directory/Non-recursively
Walk a directory/Non-recursively
Task Walk a given directory and print the names of files matching a given pattern. (How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?) Note: This task is for non-recursive methods.   These tasks should read a single directory, not an entire directory tree. ...
#zkl
zkl
File.glob("*.zkl") //--> list of matches
http://rosettacode.org/wiki/Walk_a_directory/Non-recursively
Walk a directory/Non-recursively
Task Walk a given directory and print the names of files matching a given pattern. (How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?) Note: This task is for non-recursive methods.   These tasks should read a single directory, not an entire directory tree. ...
#Zsh
Zsh
print -l -- *.c
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   ...
#PicoLisp
PicoLisp
(let Dir "." (recur (Dir) (for F (dir Dir) (let Path (pack Dir "/" F) (cond ((=T (car (info Path))) # Is a subdirectory? (recurse Path) ) # Yes: Recurse ((match '`(chop "s@.l") (chop F)) # Matches 's*.l'? ...
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   ...
#Pop11
Pop11
lvars repp, fil; ;;; create path repeater sys_file_match('.../*.p', '', false, 0) -> repp; ;;; iterate over paths while (repp() ->> fil) /= termin do  ;;; print the path printf(fil, '%s\n'); endwhile;
http://rosettacode.org/wiki/Water_collected_between_towers
Water collected between towers
Task In a two-dimensional world, we begin with any bar-chart (or row of close-packed 'towers', each of unit width), and then it rains, completely filling all convex enclosures in the chart with water. 9 ██ 9 ██ 8 ██ 8 ██ 7 ██ ...
#Raku
Raku
sub max_l ( @a ) { [\max] @a } sub max_r ( @a ) { ([\max] @a.reverse).reverse }   sub water_collected ( @towers ) { return 0 if @towers <= 2;   my @levels = max_l(@towers) »min« max_r(@towers);   return ( @levels »-« @towers ).grep( * > 0 ).sum; }   say map &water_collected, [ 1, 5, 3, 7, 2 ], [ 5...
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#AppleScript
AppleScript
--------------------- VECTOR PRODUCTS ---------------------   -- dotProduct :: Num a => [a] -> [a] -> Either String a on dotProduct(xs, ys) -- Dot product of two vectors of equal dimension.   if length of xs = length of ys then |Right|(sum(zipWith(my mul, xs, ys))) else |Left|("Dot product n...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#Tcl
Tcl
proc distcheck {random times {delta 1}} { for {set i 0} {$i<$times} {incr i} {incr vals([uplevel 1 $random])} set target [expr {$times / [array size vals]}] foreach {k v} [array get vals] { if {abs($v - $target) > $times * $delta / 100.0} { error "distribution potentially skewed for $k: ...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#C.2B.2B
C++
#include <array> #include <iostream>   int main() { constexpr std::array s {1,2,2,3,4,4,5};   if(!s.empty()) { int previousValue = s[0];   for(size_t i = 1; i < s.size(); ++i) { // in C++, variables in block scope are reset at each iteration const int currentValue = s[i];   if(i > 0 ...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#F.23
F#
  // Variable declaration reset. Nigel Galloway: June 21st 2022 let s=[1;2;2;3;4;4;5] // First let me write this in real F#, which rather avoids the whole issue printfn "Real F#" s|>List.pairwise|>List.iteri(fun i (n,g)->if n=g then printfn "%d" (i+1)) // Now let me take the opportunity to write some awful F# by transl...
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#360_Assembly
360 Assembly
* value of F L 2,F assigment r2=f * reference (or address) of F LA 3,F reference r3=@f * referencing (or indexing) of reg3 (r3->f) L 4,0(3) referencing r4=%r3=%@f=f
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#6502_Assembly
6502 Assembly
org $1200 SoundRam equ $1200  ;some assemblers require equ directives to not be indented. SoundChannel_One equ $1200 SoundChannel_Two equ $1201 SoundChannel_Three equ $1202 LDA #$FF ;this still gets assembled starting at $1200, since equ directives don't take up space!
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#8080_Assembly
8080 Assembly
org 100h lxi h,ecks ; Zero out 2000 bytes lxi b,0 lxi d,2000 zero: mov m,b inx h dcx d mov a,d ora e jnz zero lxi b,-1 ; BC = Outer loop variable outer: inx b mvi a,3 ; Are we there yet? 1000 = 03E8h cmp b ; Compare high byte jnz go mvi a,0E8h ; Compare low byte cmp c jz done go: mov d,b ; DE = Inner l...
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#8086_Assembly
8086 Assembly
LIMIT: equ 1000 cpu 8086 org 100h section .text mov di,eck ; Zero out the memory xor ax,ax mov cx,LIMIT rep stosw mov bx,eck ; Base address mov cx,LIMIT ; Limit xor ax,ax mov si,-1 ; Outer loop index outer: inc si dec cx jcxz done mov di,si ; Inner loop index inner: dec di js outer shl si,1 ; Shif...
http://rosettacode.org/wiki/Vampire_number
Vampire number
A vampire number is a natural decimal number with an even number of digits,   that can be factored into two integers. These two factors are called the   fangs,   and must have the following properties:   they each contain half the number of the decimal digits of the original number   together they consist of exactl...
#11l
11l
-V Pow10 = (0..18).map(n -> Int64(10) ^ n)   F isOdd(n) R (n [&] 1) != 0   F fangs(n) [(Int64, Int64)] r   V nDigits = sorted(String(n)) I isOdd(nDigits.len) R r   V fangLen = nDigits.len I/ 2 V inf = Pow10[fangLen - 1] L(d) inf .< inf * 10 I n % d != 0 L.continue V q = n...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#xTalk
xTalk
  on DecToVLQ Ask "Enter base 10 value:" -- input dialog box if it is not empty then if it is a number then put it into theString if isWholeNumString(theString) is false then -- I think there is built in equivalent for this but I rolled my own! answer "Only Whole Decimal Number...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
toOctets[n_Integer] := StringJoin @@@ Partition[ PadLeft[Characters@IntegerString[n, 16], 2 Ceiling[Plus @@ DigitCount[n, 16]/2], {"0"}], 2] fromOctets[octets_List] := FromDigits[StringJoin @@ octets, 16] Grid[{#, toOctets@#, fromOctets[toOctets@#]} & /@ {16^^3ffffe, 16^^1fffff, 16^^200000}]
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Clojure
Clojure
(defn foo [& args] (doseq [a args] (println a)))   (foo :bar :baz :quux) (apply foo [:bar :baz :quux])
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#COBOL
COBOL
  program-id. dsp-str is external. data division. linkage section. 1 cnt comp-5 pic 9(4). 1 str pic x. procedure division using by value cnt by reference str delimited repeated 1 to 5. end program dsp-str.   program-id. variadic. procedure divisi...
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Common_Lisp
Common Lisp
(let ((a (cons 1 2)) (b (make-array 10)) (c "a string")) (list (hcl:find-object-size a) (hcl:find-object-size b) (hcl:find-object-size c)))
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#D
D
int i ; writefln(i.sizeof) ; // print 4 int[13] ints1 ; // static integer array of length 13 writefln(ints1.sizeof) ; // print 52 int[] ints2 = new int[13] ; // dynamic integer array, variable length, currently 13 writefln(ints2.sizeof) ; // print 8, all dynamic array has this size writefln(in...
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Haskell
Haskell
  add (u,v) (x,y) = (u+x,v+y) minus (u,v) (x,y) = (u-x,v-y) multByScalar k (x,y) = (k*x,k*y) divByScalar (x,y) k = (x/k,y/k)   main = do let vecA = (3.0,8.0) -- cartersian coordinates let (r,theta) = (3,pi/12) :: (Double,Double) let vecB = (r*(cos theta),r*(sin theta)) -- from polar coordinates to cartes...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#Rust
Rust
  use statrs::function::gamma::gamma_li;   fn chi_distance(dataset: &[u32]) -> f64 { let expected = f64::from(dataset.iter().sum::<u32>()) / dataset.len() as f64; dataset .iter() .fold(0., |acc, &elt| acc + (elt as f64 - expected).powf(2.)) / expected }   fn chi2_probability(dof: f64, di...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#Scala
Scala
import org.apache.commons.math3.special.Gamma.regularizedGammaQ   object ChiSquare extends App { private val dataSets: Seq[Seq[Double]] = Seq( Seq(199809, 200665, 199607, 200270, 199649), Seq(522573, 244456, 139979, 71531, 21461) )   private def χ2IsUniform(data: Seq[Double], significance: Doubl...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Lambdatalk
Lambdatalk
  {def vigenere {def vigenere.map {lambda {:code :key :txt} {S.map {{lambda {:code :txt :key :i} {W.code2char {+ {% {+ {W.char2code {W.get :i :txt}} {if :code then {W.char2code {W.get {% :i {W.length :key}} :key}} else {- 26 {W.char2code {W.g...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Racket
Racket
  #lang racket/base   (define (visualize t0) (let loop ([t t0] [last? #t] [indent '()]) (define (I mid last) (cond [(eq? t t0) ""] [last? mid] [else last])) (for-each display (reverse indent)) (unless (eq? t t0) (printf "|\n")) (for-each display (reverse indent)) (printf "~a~a\n" (I "\\-" "+-") (c...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#Raku
Raku
sub visualize-tree($tree, &label, &children, :$indent = '', :@mid = ('├─', '│ '), :@end = ('└─', ' '), ) { sub visit($node, *@pre) { | gather { take @pre[0] ~ label($node); my @children := children($node); my $end ...
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   ...
#PowerShell
PowerShell
Get-ChildItem -Recurse -Include *.mp3
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   ...
#Prolog
Prolog
  % submitted by Aykayayciti (Earl Lamont Montgomery) % altered from fsaenzperez April 2019 % (swi-prolog.discourse-group) test_run :- proc_dir('C:\\vvvv\\vvvv_beta_39_x64').   proc_dir(Directory) :- format('Directory: ~w~n',[Directory]), directory_files(Directory,Files),!, %cut inserted proc_file...
http://rosettacode.org/wiki/Water_collected_between_towers
Water collected between towers
Task In a two-dimensional world, we begin with any bar-chart (or row of close-packed 'towers', each of unit width), and then it rains, completely filling all convex enclosures in the chart with water. 9 ██ 9 ██ 8 ██ 8 ██ 7 ██ ...
#REXX
REXX
/* REXX */ Call bars '1 5 3 7 2' Call bars '5 3 7 2 6 4 5 9 1 2' Call bars '2 6 3 5 2 8 1 4 2 2 5 3 5 7 4 1' Call bars '5 5 5 5' Call bars '5 6 7 8' Call bars '8 7 7 6' Call bars '6 7 10 7 6' Exit bars: Parse Arg bars bar.0=words(bars) high=0 box.=' ' Do i=1 To words(bars) bar.i=word(bars,i) high=max(high,bar.i) ...
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#Arturo
Arturo
; dot product dot: function [a b][ sum map couple a b => product ]   ; cross product cross: function [a b][ A: (a\1 * b\2) - a\2 * b\1 B: (a\2 * b\0) - a\0 * b\2 C: (a\0 * b\1) - a\1 * b\0 @[A B C] ]   ; scalar triple product stp: function [a b c][ dot a cross b c ]   ; vector triple product vtp...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#VBScript
VBScript
Option Explicit   sub verifydistribution(calledfunction, samples, delta) Dim i, n, maxdiff 'We could cheat via Dim d(7), but "7" wasn't mentioned in the Task. Heh. Dim d : Set d = CreateObject("Scripting.Dictionary") wscript.echo "Running """ & calledfunction & """ " & samples & " times..." for i = 1 to samples ...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#Vlang
Vlang
import rand import rand.seed import math // "given" fn dice5() int { return rand.intn(5) or {0} + 1 }   // fntion specified by task "Seven-sided dice from five-sided dice" fn dice7() int { mut i := 0 for { i = 5*dice5() + dice5() if i < 27 { break } } return (i / ...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Naive
Verify distribution uniformity/Naive
This task is an adjunct to Seven-sided dice from five-sided dice. Task Create a function to check that the random integers returned from a small-integer generator function have uniform distribution. The function should take as arguments: The function (or object) producing random integers. The number of times ...
#Wren
Wren
import "random" for Random import "/fmt" for Fmt import "/sort" for Sort   var r = Random.new()   var dice5 = Fn.new { 1 + r.int(5) }   var checkDist = Fn.new { |gen, nRepeats, tolerance| var occurs = {} for (i in 1..nRepeats) { var d = gen.call() occurs[d] = occurs.containsKey(d) ? occurs[d] + ...
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Factor
Factor
USING: kernel math prettyprint sequences ;   [let { 1 2 2 3 4 4 5 } :> s s length <iota> [| i | i s nth -1 :> ( curr prev! ) i 0 > curr prev = and [ i . ] when curr prev! ] each ]
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#FreeBASIC
FreeBASIC
Dim As Integer s(1 To 7) => {1,2,2,3,4,4,5} For i As Integer = 1 To Ubound(s) Dim As Integer curr = s(i), prev If i > 1 And curr = prev Then Print i prev = curr Next i Sleep
http://rosettacode.org/wiki/Variable_declaration_reset
Variable declaration reset
A decidely non-challenging task to highlight a potential difference between programming languages. Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ...
#Go
Go
package main   import "fmt"   func main() { s := []int{1, 2, 2, 3, 4, 4, 5}   // There is no output as 'prev' is created anew each time // around the loop and set implicitly to zero. for i := 0; i < len(s); i++ { curr := s[i] var prev int if i > 0 && curr == prev { fm...
http://rosettacode.org/wiki/Van_der_Corput_sequence
Van der Corput sequence
When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of 2 0 {\displaystyle 2^{0}} ; the digit in the next column to the left has a multiplier of 2 1 {\displaystyle 2^{1}} ; and so o...
#11l
11l
F vdc(=n, base = 2) V (vdc, denom) = (0.0, 1) L n != 0 denom *= base (n, V remainder) = divmod(n, base) vdc += Float(remainder) / denom R vdc   print((0.<10).map(i -> vdc(i))) print((0.<10).map(i -> vdc(i, 3)))
http://rosettacode.org/wiki/Variables
Variables
Task Demonstrate a language's methods of:   variable declaration   initialization   assignment   datatypes   scope   referencing,     and   other variable related facilities
#68000_Assembly
68000 Assembly
MyVar: DC.L 0 ;reserves 4 bytes of storage. The label MyVar represents the address of the four 0 bytes shown here.   MyOtherVar: DC.L $C0 ;reserves 8 bytes of storage. The first four bytes are initialized to 00 00 00 C0 and the second four to $00 $00 $01 $F4. DC.L 500 ;MyOtherVar points to the first four bytes...
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#AArch64_Assembly
AArch64 Assembly
  /* ARM assembly AARCH64 Raspberry PI 3B */ /* program vanEckSerie64.s */   /*******************************************/ /* Constantes file */ /*******************************************/ /* for this file see task include a file in language AArch64 assembly */ .include "../includeConstante...
http://rosettacode.org/wiki/Van_Eck_sequence
Van Eck sequence
The sequence is generated by following this pseudo-code: A: The first term is zero. Repeatedly apply: If the last term is *new* to the sequence so far then: B: The next term is zero. Otherwise: C: The next term is how far back this last term occured previously. Example Using ...
#Action.21
Action!
INT FUNC LastPos(INT ARRAY a INT count,value) INT pos   pos=count-1 WHILE pos>=0 AND a(pos)#value DO pos==-1 OD RETURN (pos)   PROC Main() DEFINE MAX="1000" INT ARRAY seq(MAX) INT i,pos   seq(0)=0 FOR i=1 TO MAX-1 DO pos=LastPos(seq,i-1,seq(i-1)) IF pos>=0 THEN seq(i)=i-1-pos ...
http://rosettacode.org/wiki/Vampire_number
Vampire number
A vampire number is a natural decimal number with an even number of digits,   that can be factored into two integers. These two factors are called the   fangs,   and must have the following properties:   they each contain half the number of the decimal digits of the original number   together they consist of exactl...
#AutoHotkey
AutoHotkey
SetBatchLines -1 ; used to improve performance ; (you can make it much faster by removing the informative tooltips)   ;******************** ; CONFIG ;******************** StartingNumber := 10 NumberLimit := 126030 CounterLimit := 25 ; calculations stop when one of these limits is reached AdditionalNumbers := "167582432...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#Nim
Nim
import strformat   proc toSeq(x: uint64): seq[uint8] = var x = x var f = 0u64 for i in countdown(9u64, 1): if (x and 127'u64 shl (i * 7)) > 0: f = i break for j in 0u64..f: result.add uint8((x shr ((f - j) * 7)) and 127) or 128   result[f] = result[f] xor 128'u8   proc fromSeq(xs: openArra...
http://rosettacode.org/wiki/Variable-length_quantity
Variable-length quantity
Implement some operations on variable-length quantities, at least including conversions from a normal number in the language to the binary representation of the variable-length quantity for that number, and vice versa. Any variants are acceptable. Task With above operations, convert these two numbers 0x200000 (209...
#OCaml
OCaml
let to_vlq n = let a, b = n lsr 7, n land 0x7F in let rec aux n acc = let x = (n land 0x7F) lor 0x80 and xs = n lsr 7 in if xs > 0 then aux xs (x::acc) else x::acc in aux a [b]   let to_num = List.fold_left (fun n x -> n lsl 7 + (x land 0x7F)) 0   let v_rep n = Printf.printf "%d ->" n; l...
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Common_Lisp
Common Lisp
(defun example (&rest args) (dolist (arg args) (print arg)))   (example "Mary" "had" "a" "little" "lamb")   (let ((args '("Mary" "had" "a" "little" "lamb"))) (apply #'example args))
http://rosettacode.org/wiki/Variadic_function
Variadic function
Task Create a function which takes in a variable number of arguments and prints each one on its own line. Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime. Functions of this type are also known as Variadic Functions. Related task   Call a function...
#Coq
Coq
  Fixpoint Arity (A B: Set) (n: nat): Set := match n with |O => B |S n' => A -> (Arity A B n') end.  
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Delphi
Delphi
i := sizeof({any variable or data type identifier});
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Elixir
Elixir
list = [1,2,3] IO.puts length(list) #=> 3   tuple = {1,2,3,4} IO.puts tuple_size(tuple) #=> 4   string = "Elixir" IO.puts String.length(string) #=> 6 IO.puts byte_size(string) #=> 6 IO.puts bit_size(string) #=> 48   utf8 = "○×△" IO.puts String.leng...
http://rosettacode.org/wiki/Variable_size/Get
Variable size/Get
Demonstrate how to get the size of a variable. See also: Host introspection
#Erlang
Erlang
24> erlang:tuple_size( {1,2,3} ). 3 25> erlang:length( [1,2,3] ). 3 29> erlang:bit_size( <<1:11>> ). 11 30> erlang:byte_size( <<1:11>> ). 2
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#J
J
5 7+2 3 7 10 5 7-2 3 3 4 5 7*11 55 77 5 7%2 2.5 3.5
http://rosettacode.org/wiki/Vector
Vector
Task Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented. The Vector may be initialized in any reasonable way. Start and end points, and direction Angular coefficient and value (length) The four operations to...
#Java
Java
import java.util.Locale;   public class Test {   public static void main(String[] args) { System.out.println(new Vec2(5, 7).add(new Vec2(2, 3))); System.out.println(new Vec2(5, 7).sub(new Vec2(2, 3))); System.out.println(new Vec2(5, 7).mult(11)); System.out.println(new Vec2(5, 7).div...
http://rosettacode.org/wiki/Verify_distribution_uniformity/Chi-squared_test
Verify distribution uniformity/Chi-squared test
Task Write a function to verify that a given distribution of values is uniform by using the χ 2 {\displaystyle \chi ^{2}} test to see if the distribution has a likelihood of happening of at least the significance level (conventionally 5%). The function should return a boolean that is true if the distribut...
#Sidef
Sidef
# Confluent hypergeometric function of the first kind F_1(a;b;z) func F1(a, b, z, limit=100) { sum(0..limit, {|k| rising_factorial(a, k) / rising_factorial(b, k) * z**k / k! }) }   func γ(a,x) { # lower incomplete gamma function γ(a,x) #a**(-1) * x**a * F1(a, a+1, -x) # simpler formula...
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher
Vigenère cipher
Task Implement a   Vigenère cypher,   both encryption and decryption. The program should handle keys and text of unequal length, and should capitalize everything and discard non-alphabetic characters. (If your program handles non-alphabetic characters in another way, make a note of it.) Related tasks   Caesar ...
#Liberty_BASIC
Liberty BASIC
  ori$ = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!" key$ = filter$("vigenerecipher") print ori$ print key$ enc$ = encrypt$(ori$, key$) print enc$ dec$ = decrypt$(enc$, key$) print dec$   end   function encrypt$(text$, key$) flt$ = filter$(text$) encrypt$ = "" j = 1 for i...
http://rosettacode.org/wiki/Visualize_a_tree
Visualize a tree
A tree structure   (i.e. a rooted, connected acyclic graph)   is often used in programming. It's often helpful to visually examine such a structure. There are many ways to represent trees to a reader, such as:   indented text   (à la unix tree command)   nested HTML tables   hierarchical GUI widgets   2D   or ...
#REXX
REXX
/* REXX *************************************************************** * 10.05.2014 Walter Pachl using the tree and the output format of C **********************************************************************/ Call mktree Say node.1.0name Call tt 1,'' Exit   tt: Procedure Expose node. /*******************************...
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   ...
#PureBasic
PureBasic
Procedure.s WalkRecursive(dir,path.s,Pattern.s="\.txt$") Static RegularExpression If Not RegularExpression RegularExpression=CreateRegularExpression(#PB_Any,Pattern) EndIf   While NextDirectoryEntry(dir) If DirectoryEntryType(dir)=#PB_DirectoryEntry_Directory If DirectoryEntryName(dir)<>"." And D...
http://rosettacode.org/wiki/Water_collected_between_towers
Water collected between towers
Task In a two-dimensional world, we begin with any bar-chart (or row of close-packed 'towers', each of unit width), and then it rains, completely filling all convex enclosures in the chart with water. 9 ██ 9 ██ 8 ██ 8 ██ 7 ██ ...
#Ruby
Ruby
  def a(array) n=array.length left={} right={} left[0]=array[0] i=1 loop do break if i >=n left[i]=[left[i-1],array[i]].max i += 1 end right[n-1]=array[n-1] i=n-2 loop do break if i<0 right[i]=[right[i+1],array[i]].max i-=1 end i=0 water=0 loop do break if i>=n water+=[left[i],right[i]].min-array[i] i+=1 end ...
http://rosettacode.org/wiki/Vector_products
Vector products
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers:   (X, Y, Z). If you imagine a graph with the   x   and   y   axis being at right angles to each other and having a third,   z   axis coming out of the page, then a triplet of numbers,   (X, Y, Z)   would repr...
#AutoHotkey
AutoHotkey
V := {a: [3, 4, 5], b: [4, 3, 5], c: [-5, -12, -13]}   for key, val in V Out .= key " = (" val[1] ", " val[2] ", " val[3] ")`n"   CP := CrossProduct(V.a, V.b) VTP := VectorTripleProduct(V.a, V.b, V.c)   MsgBox, % Out "`na • b = " DotProduct(V.a, V.b) "`n" . "a x b = (" CP[1] ", " CP[2] ", " CP[3] ")`n" . "a • b x c ...
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number
Validate International Securities Identification Number
An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond. Task Write a function or program that takes a string as input, and checks whether it is a valid ISIN. It is only valid if it has the correct format,   and   the embedded c...
#11l
11l
F check_isin(a) I a.len != 12 R 0B [Int] s L(c) a I c.is_digit() I L.index < 2 R 0B s.append(c.code - 48) E I c.is_uppercase() I L.index == 11 R 0B V (d, m) = divmod(c.code - 55, 10) s [+]= [d, m] E R 0B V ...