task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k |
|---|---|---|---|---|---|
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #C.23 | C# | using System;
using System.Collections.Generic;
namespace RandomLatinSquares {
using Matrix = List<List<int>>;
// Taken from https://stackoverflow.com/a/1262619
static class Helper {
private static readonly Random rng = new Random();
public static void Shuffle<T>(this IList<T> list) {
... |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Given a point and a polygon, check if the point is inside or out... | #OCaml | OCaml | type point = { x:float; y:float }
type polygon = {
vertices: point array;
edges: (int * int) list;
}
let p x y = { x=x; y=y }
let square_v = [|
(p 0. 0.); (p 10. 0.); (p 10. 10.); (p 0. 10.);
(p 2.5 2.5); (p 7.5 0.1); (p 7.5 7.5); (p 2.5 7.5)
|]
let esa_v = [|
(p 3. 0.); (p 7. 0.); (p 10. 5.); (p 7. 1... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #11l | 11l | Deque[String] my_queue
my_queue.append(‘foo’)
my_queue.append(‘bar’)
my_queue.append(‘baz’)
print(my_queue.pop_left())
print(my_queue.pop_left())
print(my_queue.pop_left()) |
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... | #Phixmonti | Phixmonti | include ..\Utilitys.pmt
argument 1 get "r" fopen var f drop
0
7 for
f fgets number? if f fclose exitfor else nip nip endif
endfor
print /# show -1 if past eof #/ |
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... | #PHP | PHP | <?php
$DOCROOT = $_SERVER['DOCUMENT_ROOT'];
function fileLine ($lineNum, $file) {
$count = 0;
while (!feof($file)) {
$count++;
$line = fgets($file);
if ($count == $lineNum) return $line;
}
die("Requested file has fewer than ".$lineNum." lines!");
}
@ $fp = fopen("$DOCROOT... |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #J | J | NB. no trailing linefeed
A=: '1 2 3'
NB. removing linefeed
A=: 0 : 0-.LF
1 2 3
)
NB. removing linefeed
A=: {{)n
1 2 3
}}-.LF |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #jq | jq | def data:
"A string", 1, {"a":0}, [1,2,[3]]
;
|
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Julia | Julia |
julia> str = "Hello, world.\n"
"Hello, world.\n"
julia> """Contains "quote" characters and
a newline"""
"Contains \"quote\" characters and \na newline"
|
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Lua | Lua | s1 = "This is a double-quoted 'string' with embedded single-quotes."
s2 = 'This is a single-quoted "string" with embedded double-quotes.'
s3 = "this is a double-quoted \"string\" with escaped double-quotes."
s4 = 'this is a single-quoted \'string\' with escaped single-quotes.'
s5 = [[This is a long-bracket "'string'" w... |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
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
... | #Action.21 | Action! | PROC Swap(BYTE ARRAY tab INT i,j)
BYTE tmp
tmp=tab(i) tab(i)=tab(j) tab(j)=tmp
RETURN
BYTE FUNC QuickSelect(BYTE ARRAY tab INT count,index)
INT px,i,j,k
BYTE pv
DO
px=count/2
pv=tab(px)
Swap(tab,px,count-1)
i=0
FOR j=0 TO count-2
DO
IF tab(j)<pv THEN
Swap(tab,i,j)... |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
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
... | #Ada | Ada | ----------------------------------------------------------------------
with Ada.Numerics.Float_Random;
with Ada.Text_IO;
procedure quickselect_task
is
use Ada.Numerics.Float_Random;
use Ada.Text_IO;
gen : Generator;
----------------------------------------------------------------------
--
-- procedure p... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #FreeBASIC | FreeBASIC |
Function DistanciaPerpendicular(tabla() As Double, i As Integer, ini As Integer, fin As Integer) As Double
Dim As Double dx, dy, mag, pvx, pvy, pvdot, dsx, dsy, ax, ay
dx = tabla(fin, 1) - tabla(ini, 1)
dy = tabla(fin, 2) - tabla(ini, 2)
'Normaliza
mag = (dx^2 + dy^2)^0.5
If mag > 0 Then d... |
http://rosettacode.org/wiki/Ramanujan%27s_constant | Ramanujan's constant | Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| #Julia | Julia |
julia> a = BigFloat(MathConstants.e^(BigFloat(pi)))^(BigFloat(163.0)^0.5)
2.625374126407687439999999999992500725971981856888793538563373369908627075373427e+17
julia> 262537412640768744 - a
7.499274028018143111206461436626630091372924626572825942241598957614307213309258e-13
|
http://rosettacode.org/wiki/Ramanujan%27s_constant | Ramanujan's constant | Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | First[RealDigits[N[Exp[Pi Sqrt[163]], 200]]]
Table[
c = N[Exp[Pi Sqrt[h]], 40];
Log10[1 - FractionalPart[c]]
,
{h, {19, 43, 67, 163}}
] |
http://rosettacode.org/wiki/Ramanujan%27s_constant | Ramanujan's constant | Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| #Nim | Nim | import strformat, strutils
import decimal
setPrec(75)
let pi = newDecimal("3.1415926535897932384626433832795028841971693993751058209749445923078164")
proc eval(n: int): DecimalType =
result = exp(pi * sqrt(newDecimal(n)))
func format(n: DecimalType; d: Positive): string =
## Return the representation of "n" w... |
http://rosettacode.org/wiki/Range_extraction | Range extraction | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #BBC_BASIC | BBC BASIC | range$ = " 0, 1, 2, 4, 6, 7, 8, 11, 12, 14, " + \
\ "15, 16, 17, 18, 19, 20, 21, 22, 23, 24, " + \
\ "25, 27, 28, 29, 30, 31, 32, 33, 35, 36, " + \
\ "37, 38, 39"
PRINT FNrangeextract(range$)
END
DEF FNrangeextract(r$)
LOCAL f%, i%, r%, t%, t$... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #D | D | import std.stdio, std.random, std.math;
struct NormalRandom {
double mean, stdDev;
// Necessary because it also defines an opCall.
this(in double mean_, in double stdDev_) pure nothrow {
this.mean = mean_;
this.stdDev = stdDev_;
}
double opCall() const /*nothrow*/ {
imm... |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #D | D | function Random : Extended;
function Random ( LimitPlusOne : Integer ) : Integer;
procedure Randomize;
|
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Delphi | Delphi | function Random : Extended;
function Random ( LimitPlusOne : Integer ) : Integer;
procedure Randomize;
|
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #DWScript | DWScript | !print random-int # prints a 32-bit random integer |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #D.C3.A9j.C3.A0_Vu | Déjà Vu | !print random-int # prints a 32-bit random integer |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #EchoLisp | EchoLisp |
(edit 'preferences)
;; current contents to edit is displayed in the input box
(define (preferences)
(define-syntax-rule (++ n) (begin (set! n (1+ n)) n))
(define-syntax-rule (% a b) (modulo a b))
;; (lib 'gloops)
(lib 'timer))
;; enter new preferences
(define (preferences)
(define FULLNAME "Foo Barber")
(de... |
http://rosettacode.org/wiki/Rare_numbers | Rare numbers | Definitions and restrictions
Rare numbers are positive integers n where:
n is expressed in base ten
r is the reverse of n (decimal digits)
n must be non-palindromic (n ≠ r)
(n+r) is the sum
(n-r) is the difference and must be positive
the sum and the ... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | c = Compile[{{k, _Integer}},
Module[{out = {0}, start = 0, stop = 0, rlist = {0}, r = 0,
sum = 0.0, diff = 0.0, imax = 8, step = 10},
Do[
If[j == k, imax = 2, imax = 8];
Do[
If[i == 2,
start = i 10^j + 2;
stop = (i + 1) 10^j - 1;
step = 10;
,
start = i 10^j;
s... |
http://rosettacode.org/wiki/Range_expansion | Range expansion | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #C.23 | C# | using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;
class Program
{
static void Main(string[] args)
{
var rangeString = "-6,-3--1,3-5,7-11,14,15,17-20";
var matches = Regex.Matches(rangeString, @"(?<f>-?\d+)-(?<s>-?\d+)|(-?\d+)");
va... |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #C.2B.2B | C++ | #include <fstream>
#include <string>
#include <iostream>
int main( int argc , char** argv ) {
int linecount = 0 ;
std::string line ;
std::ifstream infile( argv[ 1 ] ) ; // input file stream
if ( infile ) {
while ( getline( infile , line ) ) {
std::cout << linecount << ": "
<<... |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
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
... | #Kotlin | Kotlin | // version 1.0.6
/* all ranking functions assume the array of Pairs is non-empty and already sorted by decreasing order of scores
and then, if the scores are equal, by reverse alphabetic order of names
*/
fun standardRanking(scores: Array<Pair<Int, String>>): IntArray {
val rankings = IntArray(scores.size... |
http://rosettacode.org/wiki/Range_consolidation | Range consolidation | Define a range of numbers R, with bounds b0 and b1 covering all numbers between and including both bounds.
That range can be shown as:
[b0, b1]
or equally as:
[b1, b0]
Given two ranges, the act of consolidation between them compares the two ranges:
If one range covers all of the other then t... | #Phix | Phix | with javascript_semantics
function consolidate(sequence sets)
integer l = length(sets)
sequence res = repeat(0,l)
for i=1 to l do
atom {rs,re} = sets[i]
res[i] = iff(rs>re?{re,rs}:{rs,re})
end for
for i=l to 1 by -1 do
atom {il,ih} = res[i]
for j=l to i+1 by -1 do
... |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Oforth | Oforth | reverse |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #Groovy | Groovy | def rng = new java.security.SecureRandom() |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #Haskell | Haskell | #!/usr/bin/env runhaskell
import System.Entropy
import Data.Binary.Get
import qualified Data.ByteString.Lazy as B
main = do
bytes <- getEntropy 4
print (runGet getWord32be $ B.fromChunks [bytes]) |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #Icon_and_Unicon | Icon and Unicon | procedure main(A)
n := integer(A[1])|5
every !n do write(rand(4))
end
procedure rand(n)
f := open("/dev/urandom") | stop("Cannot get to urandom!")
x := 0
every !n do x := x*256 + ord(reads(f,1))
close(f)
return x
end |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #D | D | import std.array;
import std.random;
import std.stdio;
alias Matrix = int[][];
void latinSquare(int n) {
if (n <= 0) {
writeln("[]");
return;
}
Matrix latin = uninitializedArray!Matrix(n, n);
foreach (row; latin) {
for (int i = 0; i < n; i++) {
row[i] = i;
... |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Given a point and a polygon, check if the point is inside or out... | #Perl | Perl | use strict;
use List::Util qw(max min);
sub point_in_polygon
{
my ( $point, $polygon ) = @_;
my $count = 0;
foreach my $side ( @$polygon ) {
$count++ if ray_intersect_segment($point, $side);
}
return ($count % 2 == 0) ? 0 : 1;
}
my $eps = 0.0001;
my $inf = 1e600;
sub ray_intersect_segment... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #6502_Assembly | 6502 Assembly |
queuePointerStart equ #$FD
queuePointerMinus1 equ #$FC ;make this equal whatever "queuePointerStart" is, minus 1.
pushQueue:
STA 0,x
DEX
RTS
popQueue:
STX temp
LDX #queuePointerStart
LDA 0,x ;get the item that's first in line
PHA
LDX #queuePointerMinus1
loop_popQueue:
LDA 0,X
STA 1,X
DEX
... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #8th | 8th |
10 q:new \ create a new queue 10 deep
123 q:push
341 q:push \ push 123, 341 onto the queue
q:pop . cr \ displays 123
q:len . cr \ displays 1
q:pop . cr \ displays 341
q:len . cr \ displays 0
|
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... | #PicoLisp | PicoLisp | (in "file.txt"
(do 6 (line))
(or (line) (quit "No 7 lines")) ) |
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... | #PL.2FI | PL/I |
declare text character (1000) varying, line_no fixed;
get (line_no);
on endfile (f) begin;
put skip list ('the specified line does not exist');
go to next;
end;
get file (f) edit ((text do i = 1 to line_no)) (L);
put skip list (text);
next: ;
|
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Nim | Nim |
echo "A simple string."
echo "A simple string including tabulation special character \\t: \t."
echo """
First part of a multiple string,
followed by second part
and third part.
"""
echo r"A raw string containing a \."
# Interpolation in strings.
import strformat
const C = "constant"
const S = fmt"A string with ... |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Phix | Phix | constant t123 = `
one
two
three
`
|
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Raku | Raku | /*REXX program demonstrates various ways to express a string of characters or numbers.*/
a= 'This is one method of including a '' (an apostrophe) within a string.'
b= "This is one method of including a ' (an apostrophe) within a string."
/*sometimes, an apostrophe i... |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #ALGOL_68 | ALGOL 68 | BEGIN
# returns the kth lowest element of list using the quick select algorithm #
PRIO QSELECT = 1;
OP QSELECT = ( INT k, REF[]INT list )INT:
IF LWB list > UPB list THEN
# empty list #
0
ELSE
# non-empty list #
# partitions the subset o... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #Go | Go | package main
import (
"fmt"
"math"
)
type point struct{ x, y float64 }
func RDP(l []point, ε float64) []point {
x := 0
dMax := -1.
last := len(l) - 1
p1 := l[0]
p2 := l[last]
x21 := p2.x - p1.x
y21 := p2.y - p1.y
for i, p := range l[1:last] {
if d := math.Abs(y21*p.... |
http://rosettacode.org/wiki/Ramanujan%27s_constant | Ramanujan's constant | Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| #Pari.2FGP | Pari/GP | \p 50
exp(Pi*sqrt(163)) |
http://rosettacode.org/wiki/Ramanujan%27s_constant | Ramanujan's constant | Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| #Perl | Perl | use strict;
use warnings;
use Math::AnyNum;
sub ramanujan_const {
my ($x, $decimals) = @_;
$x = Math::AnyNum->new($x);
my $prec = (Math::AnyNum->pi * $x->sqrt)/log(10) + $decimals + 1;
local $Math::AnyNum::PREC = 4*$prec->round->numify;
exp(Math::AnyNum->pi * $x->sqrt)->round(-$decimals)->stri... |
http://rosettacode.org/wiki/Range_extraction | Range extraction | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Bracmat | Bracmat | ( rangeExtract
= accumulator firstInRange nextInRange
, accumulate fasten rangePattern
. ( accumulate
= !accumulator
(!accumulator:|?&",")
!firstInRange
( !firstInRange+1:<>!nextInRange
& ( !firstInRange+2:!nextInRange&","
... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Delphi | Delphi | program Randoms;
{$APPTYPE CONSOLE}
uses
Math;
var
Values: array[0..999] of Double;
I: Integer;
begin
// Randomize; Commented to obtain reproducible results
for I:= Low(Values) to High(Values) do
Values[I]:= RandG(1.0, 0.5); // Mean = 1.0, StdDev = 0.5
Writeln('Mean = ', Mean(Values):... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #DWScript | DWScript | var values : array [0..999] of Float;
var i : Integer;
for i := values.Low to values.High do
values[i] := RandG(1, 0.5); |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #EchoLisp | EchoLisp |
(random-seed "albert")
(random) → 0.9672510261922906 ; random float in [0 ... 1[
(random 1000) → 726 ; random integer in [0 ... 1000 [
(random -1000) → -936 ; random integer in ]-1000 1000[
(lib 'bigint)
(random 1e200) → 48635656441292641677...3917639734865662239925...9490799697903133046309616766848265781368
|
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Elena | Elena | import extensions;
public program()
{
console.printLine(randomGenerator.nextReal());
console.printLine(randomGenerator.eval(0,100))
} |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Elixir | Elixir |
# Seed the RNG
:random.seed(:erlang.now())
# Integer in the range 1..10
:random.uniform(10)
# Float between 0.0 and 1.0
:random.uniform()
|
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Erlang | Erlang |
random:seed(A1, A2, A3)
|
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Elixir | Elixir | defmodule Configuration_file do
def read(file) do
File.read!(file)
|> String.split(~r/\n|\r\n|\r/, trim: true)
|> Enum.reject(fn line -> String.starts_with?(line, ["#", ";"]) end)
|> Enum.map(fn line ->
case String.split(line, ~r/\s/, parts: 2) do
[option] -> {to_atom(optio... |
http://rosettacode.org/wiki/Rare_numbers | Rare numbers | Definitions and restrictions
Rare numbers are positive integers n where:
n is expressed in base ten
r is the reverse of n (decimal digits)
n must be non-palindromic (n ≠ r)
(n+r) is the sum
(n-r) is the difference and must be positive
the sum and the ... | #Nim | Nim | import algorithm, math, strformat, times
type Llst = seq[seq[int]]
const
# Powers of 10.
P = block:
var p: array[19, int64]
p[0] = 1i64
for i in 1..18: p[i] = 10 * p[i - 1]
p
# Digital root lookup array.
Drar = block:
var drar: array[19, int]
for i in ... |
http://rosettacode.org/wiki/Range_expansion | Range expansion | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #C.2B.2B | C++ | #include <iostream>
#include <sstream>
#include <iterator>
#include <climits>
#include <deque>
// parse a list of numbers with ranges
//
// arguments:
// is: the stream to parse
// out: the output iterator the parsed list is written to.
//
// returns true if the parse was successful. false otherwise
template<typen... |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Clojure | Clojure |
(with-open [r (clojure.java.io/reader "some-file.txt")]
(doseq [l (line-seq r)]
(println l)))
|
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #CLU | CLU | start_up = proc ()
po: stream := stream$primary_output()
% There is a special type for file names. This ensures that
% the path is valid; if not, file_name$parse would throw an
% exception (which we are just ignoring here).
fname: file_name := file_name$parse("input.txt")
% File I/O is then ... |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
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
exec 2> /tmp/Ranking_methods.err
# Ranking methods
#
# # Standard. (Ties share what would have been their first ordinal number).
# # Modified. (Ties share what would have been their last ordinal number).
# # Dense. (Ties share the next available integer).
# # Ordinal. ((Competitors take the next available ... |
http://rosettacode.org/wiki/Range_consolidation | Range consolidation | Define a range of numbers R, with bounds b0 and b1 covering all numbers between and including both bounds.
That range can be shown as:
[b0, b1]
or equally as:
[b1, b0]
Given two ranges, the act of consolidation between them compares the two ranges:
If one range covers all of the other then t... | #Prolog | Prolog | consolidate_ranges(Ranges, Consolidated):-
normalize(Ranges, Normalized),
sort(Normalized, Sorted),
merge(Sorted, Consolidated).
normalize([], []):-!.
normalize([r(X, Y)|Ranges], [r(Min, Max)|Normalized]):-
(X > Y -> Min = Y, Max = X; Min = X, Max = Y),
normalize(Ranges, Normalized).
merge([], [... |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Ol | Ol |
(define (rev s)
(runes->string (reverse (string->runes s))))
; testing:
(print (rev "Hello, λ!"))
; ==> !λ ,olleH
|
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #J | J | 256#.a.i.1!:11'/dev/urandom';0 4 |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #Java | Java | import java.security.SecureRandom;
public class RandomExample {
public static void main(String[] args) {
SecureRandom rng = new SecureRandom();
/* Prints a random signed 32-bit integer. */
System.out.println(rng.nextInt());
}
} |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #F.23 | F# |
// Generate 2 Random Latin Squares of order 5. Nigel Galloway: July 136th., 2019
let N=let N=System.Random() in (fun n->N.Next(n))
let rc()=let β=lN2p [|0;N 4;N 3;N 2|] [|0..4|] in Seq.item (N 56) (normLS 5) |> List.map(lN2p [|N 5;N 4;N 3;N 2|]) |> List.permute(fun n->β.[n]) |> List.iter(printfn "%A")
rc(); printfn "... |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Given a point and a polygon, check if the point is inside or out... | #Phix | Phix | constant inf = 1e300*1e300
function rayIntersectsSegment(sequence point, sequence segment)
sequence {a, b} = segment
atom {pX,pY} = point,
{aX,aY} = a,
{bX,bY} = b,
m_red,m_blue
-- ensure {aX,aY} is the segment end-point with the smallest y coordinate
if aY>bY then
{... |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #8080_Assembly | 8080 Assembly | org 100h
lxi b,P
call A
lxi d,P
jmp B
A: ldax b
ana a
rz
call G
inx b
jmp A
B: lxi h,C
call H
mvi c,16
D: mvi a,48
call G
ldax d
... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Action.21 | Action! | SET EndProg=* |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Ada | Ada | with FIFO;
with Ada.Text_Io; use Ada.Text_Io;
procedure Queue_Test is
package Int_FIFO is new FIFO (Integer);
use Int_FIFO;
Queue : FIFO_Type;
Value : Integer;
begin
Push (Queue, 1);
Push (Queue, 2);
Push (Queue, 3);
Pop (Queue, Value);
Pop (Queue, Value);
Push (Queue, 4);
Pop (Que... |
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... | #PL.2FM | PL/M | 100H: /* READ A SPECIFIC LINE FROM A FILE */
DECLARE FALSE LITERALLY '0', TRUE LITERALLY '0FFH';
DECLARE NL$CHAR LITERALLY '0AH'; /* NEWLINE: CHAR 10 */
DECLARE EOF$CHAR LITERALLY '26'; /* EOF: CTRL-Z */
/* CP/M BDOS SYST... |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #REXX | REXX | /*REXX program demonstrates various ways to express a string of characters or numbers.*/
a= 'This is one method of including a '' (an apostrophe) within a string.'
b= "This is one method of including a ' (an apostrophe) within a string."
/*sometimes, an apostrophe i... |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
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
... | #AppleScript | AppleScript | on quickselect(theList, l, r, k)
script o
property lst : theList's items -- Shallow copy.
end script
repeat
-- Median-of-3 pivot selection.
set leftValue to item l of o's lst
set rightValue to item r of o's lst
set pivot to item ((l + r) div 2) of o's lst
se... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #J | J | mp=: +/ .* NB. matrix product
norm=: +/&.:*: NB. vector norm
normalize=: (% norm)^:(0 < norm)
dxy=. normalize@({: - {.)
pv=. -"1 {.
NB.*perpDist v Calculate perpendicular distance of points from a line
perpDist=: norm"1@(pv ([ -"1 mp"1~ */ ]) dxy) f.
rdp=: verb define
1 rdp y
:
points=. ,:^:(2... |
http://rosettacode.org/wiki/Ramanujan%27s_constant | Ramanujan's constant | Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| #Phix | Phix | without javascript_semantics -- no mpfr_exp() under p2js (yet), sorry
requires("1.0.0") -- (mpfr_set_default_prec[ision] has been renamed)
include mpfr.e
mpfr_set_default_precision(-120) -- (18 before, 100 after, plus 2 for kicks.)
function q(integer d)
mpfr pi = mpfr_init()
mpfr_const_pi(pi)
mpfr t = mpf... |
http://rosettacode.org/wiki/Range_extraction | Range extraction | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #C | C | #include <stdio.h>
#include <stdlib.h>
size_t rprint(char *s, int *x, int len)
{
#define sep (a > s ? "," : "") /* use comma except before first output */
#define ol (s ? 100 : 0) /* print only if not testing for length */
int i, j;
char *a = s;
for (i = j = 0; i < len; i = ++j) {
for (; j < len - 1 && x[j... |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #E | E | accum [] for _ in 1..1000 { _.with(entropy.nextGaussian()) } |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #EasyLang | EasyLang | for i range 1000
a[] &= 1 + 0.5 * sqrt (-2 * logn randomf) * cos (360 * randomf)
.
print a[] |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Euler_Math_Toolbox | Euler Math Toolbox |
program rosetta_random
implicit none
integer, parameter :: rdp = kind(1.d0)
real(rdp) :: num
integer, allocatable :: seed(:)
integer :: un,n, istat
call random_seed(size = n)
allocate(seed(n))
! Seed with the OS random number generator
open(newunit=un, file="/dev/urandom", access="str... |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #Factor | Factor |
program rosetta_random
implicit none
integer, parameter :: rdp = kind(1.d0)
real(rdp) :: num
integer, allocatable :: seed(:)
integer :: un,n, istat
call random_seed(size = n)
allocate(seed(n))
! Seed with the OS random number generator
open(newunit=un, file="/dev/urandom", access="str... |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Erlang | Erlang |
-module( configuration_file ).
-export( [read/1, task/0] ).
read( File ) ->
{ok, Binary} = file:read_file( File ),
Lines = [X || <<First:8, _T/binary>> = X <- binary:split(Binary, <<"\n">>, [global]), First =/= $#, First =/= $;],
[option_from_binaries(binary:split(X, <<" ">>)) || X <- Lines].
task()... |
http://rosettacode.org/wiki/Rare_numbers | Rare numbers | Definitions and restrictions
Rare numbers are positive integers n where:
n is expressed in base ten
r is the reverse of n (decimal digits)
n must be non-palindromic (n ≠ r)
(n+r) is the sum
(n-r) is the difference and must be positive
the sum and the ... | #Perl | Perl | #!/usr/bin/perl
use strict; # https://rosettacode.org/wiki/Rare_numbers
use warnings;
use integer;
my $count = 0;
my @squares;
for my $large ( 0 .. 1e5 )
{
my $largesquared = $squares[$large] = $large * $large; # $large ** 2;
for my $small ( 0 .. $large - 1 )
{
my $n = $largesquared + $squares[$small]... |
http://rosettacode.org/wiki/Range_expansion | Range expansion | A format for expressing an ordered list of integers is to use a comma separated list of either
individual integers
Or a range of integers denoted by the starting integer separated from the end integer in the range by a dash, '-'. (The range includes all integers in the interval including both endpoints)
The range s... | #Clojure | Clojure | (defn split [s sep]
(defn skipFirst [[x & xs :as s]]
(cond (empty? s) [nil nil]
(= x sep) [x xs]
true [nil s]))
(loop [lst '(), s s]
(if (empty? s) (reverse lst)
(let [[hd trunc] (skipFirst s)
[word news] (split-with #(not= % sep) trunc)
cWord (cons hd word)] ... |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #COBOL | COBOL | IDENTIFICATION DIVISION.
PROGRAM-ID. read-file-line-by-line.
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT input-file ASSIGN TO "input.txt"
ORGANIZATION LINE SEQUENTIAL
FILE STATUS input-file-status.
DATA DIVISION.... |
http://rosettacode.org/wiki/Ranking_methods | Ranking methods |
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
... | #M2000_Interpreter | M2000 Interpreter |
Module Ranking (output$, orderlist) {
Open output$ for output as #k
Gosub getdata
Print #k, "Standard ranking:"
skip=true
rankval=1
oldrank=0
For i=1 to items
Read rank, name$
if skip then
skip=false
else.if oldrank<>rank then
rankval=i
end if
oldrank=rank
Print #k, Format$("{0::-5} {2} ({1})... |
http://rosettacode.org/wiki/Range_consolidation | Range consolidation | Define a range of numbers R, with bounds b0 and b1 covering all numbers between and including both bounds.
That range can be shown as:
[b0, b1]
or equally as:
[b1, b0]
Given two ranges, the act of consolidation between them compares the two ranges:
If one range covers all of the other then t... | #Python | Python | def normalize(s):
return sorted(sorted(bounds) for bounds in s if bounds)
def consolidate(ranges):
norm = normalize(ranges)
for i, r1 in enumerate(norm):
if r1:
for r2 in norm[i+1:]:
if r2 and r1[-1] >= r2[0]: # intersect?
r1[:] = [r1[0], max(r1[... |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #OOC | OOC |
main: func {
"asdf" reverse() println() // prints "fdsa"
}
|
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #jq | jq | od -t x -An /dev/urandom | tr -d " " | fold -w 8 | jq -R -f uniform.jq |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #Julia | Julia |
const rdev = "/dev/random"
rstream = try
open(rdev, "r")
catch
false
end
if isa(rstream, IOStream)
b = readbytes(rstream, 4)
close(rstream)
i = reinterpret(Int32, b)[1]
println("A hardware random number is: ", i)
else
println("The hardware random number stream, ", rdev, ", was unavailab... |
http://rosettacode.org/wiki/Random_number_generator_(device) | Random number generator (device) | Task
If your system has a means to generate random numbers involving not only a software algorithm (like the /dev/urandom devices in Unix), then:
show how to obtain a random 32-bit number from that mechanism.
Related task
Random_number_generator_(included)
| #Kotlin | Kotlin | // version 1.1.2
import java.security.SecureRandom
fun main(args: Array<String>) {
val rng = SecureRandom()
val rn1 = rng.nextInt()
val rn2 = rng.nextInt()
val newSeed = rn1.toLong() * rn2
rng.setSeed(newSeed) // reseed using the previous 2 random numbers
println(rng.nextInt()) // get ra... |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #Factor | Factor | USING: arrays combinators.extras fry io kernel math.matrices
prettyprint random sequences sets ;
IN: rosetta-code.random-latin-squares
: rand-permutation ( n -- seq ) <iota> >array randomize ;
: ls? ( n -- ? ) [ all-unique? ] column-map t [ and ] reduce ;
: (ls) ( n -- m ) dup '[ _ rand-permutation ] replicate ;
: ls... |
http://rosettacode.org/wiki/Random_Latin_squares | Random Latin squares | A Latin square of size n is an arrangement of n symbols in an n-by-n square in such a way that each row and column has each symbol appearing exactly once.
A randomised Latin square generates random configurations of the symbols for any given n.
Example n=4 randomised Latin square
0 2 3 1
2 1 0 3
3 0 1 2
1 3 2 0
Task... | #Go | Go | package main
import (
"fmt"
"math/rand"
"time"
)
type matrix [][]int
func shuffle(row []int, n int) {
rand.Shuffle(n, func(i, j int) {
row[i], row[j] = row[j], row[i]
})
}
func latinSquare(n int) {
if n <= 0 {
fmt.Println("[]\n")
return
}
latin := make(mat... |
http://rosettacode.org/wiki/Ray-casting_algorithm | Ray-casting algorithm |
This page uses content from Wikipedia. The original article was at Point_in_polygon. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Given a point and a polygon, check if the point is inside or out... | #PHP | PHP |
<?php
function contains($bounds, $lat, $lng)
{
$count = 0;
$bounds_count = count($bounds);
for ($b = 0; $b < $bounds_count; $b++) {
$vertex1 = $bounds[$b];
$vertex2 = $bounds[($b + 1) % $bounds_count];
if (west($vertex1, $vertex2, $lng, $lat))
$count++;
}
re... |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #ABAP | ABAP | REPORT R NO STANDARD PAGE HEADING LINE-SIZE 67.
DATA:A(440),B,C,N(3) TYPE N,I TYPE I,S.
A+000 = 'REPORT R NO STANDARD PAGE HEADING LINE-SIZE 6\7.1DATA:A'.
A+055 = '(440),B,C,N(\3) TYPE N,I TYPE I,S.?1DO 440 TIMES.3C = A'.
A+110 = '+I.3IF B = S.5IF C CA `\\\?\1\3\5\7`.7B = C.5ELSEIF C ='.
A+165 = ' `\``.7WRITE ```` NO-G... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #ALGOL_68 | ALGOL 68 | # -*- coding: utf-8 -*- #
MODE DIETITEM = STRUCT(
STRING food, annual quantity, units, REAL cost
);
# Stigler's 1939 Diet ... #
FORMAT diet item fmt = $g": "g" "g" = $"zd.dd$;
[]DIETITEM stigler diet = (
("Cabbage", "111","lb.", 4.11),
("Dried Navy Beans", "285","lb.", 16.80),
("Evaporated Milk", ... |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #App_Inventor | App Inventor | on push(StackRef, value)
set StackRef's contents to {value} & StackRef's contents
return StackRef
end push
on pop(StackRef)
set R to missing value
if StackRef's contents ≠ {} then
set R to StackRef's contents's item 1
set StackRef's contents to {} & rest of StackRef's contents
end ... |
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
}
|
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... | #PureBasic | PureBasic | Structure lineLastRead
lineRead.i
line.s
EndStructure
Procedure readNthLine(file, n, *results.lineLastRead)
*results\lineRead = 0
While *results\lineRead < n And Not Eof(file)
*results\line = ReadString(file)
*results\lineRead + 1
Wend
If *results\lineRead = n
ProcedureReturn 1
EndIf
EndP... |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Ring | Ring |
text = list(3)
text[1] = "This is 'first' example for quoting"
text[2] = "This is second 'example' for quoting"
text[3] = "This is third example 'for' quoting"
for n = 1 to len(text)
see "text for quoting: " + nl + text[n] + nl
str = substr(text[n],"'","")
see "quoted text:" + nl + str + nl + nl
next
... |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Smalltalk | Smalltalk | $a
$Å
$日 |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Wren | Wren | import "/fmt" for Fmt
// simple string literal
System.print("Hello world!")
// string literal including an escape sequence
System.print("Hello tabbed\tworld!")
// interpolated string literal
var w = "world"
System.print("Hello interpolated %(w)!")
// 'printf' style
Fmt.print("Hello 'printf' style $s!", w)
// ... |
http://rosettacode.org/wiki/Quoting_constructs | Quoting constructs | Pretty much every programming language has some form of quoting construct to allow embedding of data in a program, be it literal strings, numeric data or some combination thereof.
Show examples of the quoting constructs in your language. Explain where they would likely be used, what their primary use is, what limitati... | #Z80_Assembly | Z80 Assembly | MyString:
byte "Hello World",0 ;a null-terminated string
LookupTable:
byte &03,&06,&09,&0C ;a pre-defined sequence of bytes (similar in concept to enum in C)
TileGfx:
incbin "Z:\game\gfx\tilemap.bmp" ;a file containing bitmap graphics data |
http://rosettacode.org/wiki/Quickselect_algorithm | Quickselect algorithm |
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
... | #Arturo | Arturo | quickselect: function [a k][
arr: new a
while ø [
indx: random 0 (size arr)-1
pivot: arr\[indx]
remove 'arr .index indx
left: select arr 'item -> item<pivot
right: select arr 'item -> item>pivot
case [k]
when? [= size left]-> return pivot
... |
http://rosettacode.org/wiki/Ramer-Douglas-Peucker_line_simplification | Ramer-Douglas-Peucker line simplification | Ramer-Douglas-Peucker line simplification
You are encouraged to solve this task according to the task description, using any language you may know.
The Ramer–Douglas–Peucker algorithm is a line simplification algorithm for reducing the number of points used to define its shape.
Task
Using the Ramer–Douglas–P... | #Java | Java | import javafx.util.Pair;
import java.util.ArrayList;
import java.util.List;
public class LineSimplification {
private static class Point extends Pair<Double, Double> {
Point(Double key, Double value) {
super(key, value);
}
@Override
public String toString() {
... |
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