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 | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/P-value_correction | P-value correction | Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-values are sometimes called "q... | #Perl | Perl | #!/usr/bin/env perl
use strict;
use warnings FATAL => 'all';
use autodie ':all';
use List::Util 'min';
use feature 'say';
sub pmin {
my $array = shift;
my $x = 1;
my @pmin_array;
my $n = scalar @$array;
for (my $index = 0; $index < $n; $index++) {
$pmin_array[$index] = min(@$array[$index], $x);
}
@pmin_arr... | Give a code snippet in #Perl
Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #BCPL | BCPL | get "libhdr"
let fib(n) = n<=1 -> n, valof
$( let a=0 and b=1
for i=2 to n
$( let c=a
a := b
b := a+c
$)
resultis b
$)
let start() be
for i=0 to 10 do
writef("F_%N*T= %N*N", i, fib(i)) | Give a code snippet in #BCPL
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/Output | XML/Output | Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> element.
As an example, calling ... | #SenseTalk | SenseTalk | put ("April", "Tam O'Shanter", "Emily") into names
put ("Bubbly: I'm > Tam and <= Emily", <<Burns: "When chapman billies leave the street ...">>, "Short & shrift") into remarks
put (_tag: "CharacterRemarks") as tree into document
repeat for each item name in names
insert (_tag: "Character", name: name, _children: item... | Give a code snippet in #SenseTalk
Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #DBL | DBL | XCALL TIME (D6) ;D6=hhmmss | Give a code snippet in #DBL
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Da... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mutual_recursion | Mutual recursion | Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)
=
n
−
M
(
F
(
n
−
1
)
)
,
... | #Go | Go | package main
import "fmt"
func F(n int) int {
if n == 0 { return 1 }
return n - M(F(n-1))
}
func M(n int) int {
if n == 0 { return 0 }
return n - F(M(n-1))
}
func main() {
for i := 0; i < 20; i++ {
fmt.Printf("%2d ", F(i))
}
fmt.Println()
for i := 0; i < 20; i++ {
fmt.Printf("%2d ", M(i))
... | Give a code snippet in #Go
Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Groovy | Groovy | def rFact
rFact = { (it > 1) ? it * rFact(it - 1) : 1 as BigInteger } | Give a code snippet in #Groovy
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RSA_code | RSA code | Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encryption is that you can distribute the... | #Erlang | Erlang |
%%% @author Tony Wallace <tony@tony.gen.nz>
%%% @doc
%%% For details of the algorithms used see
%%% https://en.wikipedia.org/wiki/Modular_exponentiation
%%% @end
%%% Created : 21 Jul 2021 by Tony Wallace <tony@resurrection>
-module mod.
-export [mod_mult/3,mod_exp/3,binary_exp/2,test/0].
mod_mult(I1,I2,Mod) when ... | Give a code snippet in #Erlang
Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encryptio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size_distribution | File size distribution | Task
Beginning from the current directory, or optionally from a directory specified as a command-line argument, determine how many files there are of various sizes in a directory hierarchy.
My suggestion is to sort by logarithmn of file size, since a few bytes here or there, or even a factor of two or three, may no... | #Sidef | Sidef | func traverse(Block callback, Dir dir) {
dir.open(\var dir_h) || return nil
for entry in (dir_h.entries) {
if (entry.kind_of(Dir)) {
traverse(callback, entry)
} else {
callback(entry)
}
}
}
var dir = (ARGV ? Dir(ARGV[0]) : Dir.cwd)
var group = Hash()
var... | Give a code snippet in #Sidef
Task
Beginning from the current directory, or optionally from a directory specified as a command-line argument, determine how many files there are of various sizes in a directory hierarchy.
My suggestion is to sort by logarithmn of file size, since a few bytes here or there, or even a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Cursor_positioning | Terminal control/Cursor positioning |
Task
Move the cursor to column 3, row 6, and display the word "Hello" (without the quotes), so that the letter H is in column 3 on row 6.
| #Forth | Forth | 2 5 at-xy ." Hello" | Give a code snippet in #Forth
Task
Move the cursor to column 3, row 6, and display the word "Hello" (without the quotes), so that the letter H is in column 3 on row 6.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would repr... | #Lambdatalk | Lambdatalk |
{def dotProduct
{lambda {:a :b}
{+ {* {A.get 0 :a} {A.get 0 :b}}
{* {A.get 1 :a} {A.get 1 :b}}
{* {A.get 2 :a} {A.get 2 :b}}}}}
-> dotProduct
{def crossProduct
{lambda {:a :b}
{A.new {- {* {A.get 1 :a} {A.get 2 :b}}
{* {A.get 2 :a} {A.get 1 :b}}}
{- {* {A.get 2 :a} {A.get 0 :b}... | Give a code snippet in #Lambdatalk
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Julia | Julia | # http://en.wikipedia.org/wiki/Feigenbaum_constant
function feigenbaum_delta(imax=23, jmax=20)
a1, a2, d1 = BigFloat(1.0), BigFloat(0.0), BigFloat(3.2)
println("Feigenbaum's delta constant incremental calculation:\ni δ\n1 3.20")
for i in 2:imax
a = a1 + (a1 - a2) / d1
for j in 1:jmax
... | Give a code snippet in #Julia
Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available,... | #Ruby | Ruby | # create an array with one object in it
a = ['foo']
# the Array#new method allows several additional ways to create arrays
# push objects into the array
a << 1 # ["foo", 1]
a.push(3,4,5) # ["foo", 1, 3, 4, 5]
# set the value at a specific index in the array
a[0] = 2 # [2, 1, 3, 4, 5]
# a couple o... | Give a code snippet in #Ruby
This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrie... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Simula | Simula | BEGIN
WHILE NOT LASTITEM DO
BEGIN
OUTINT(ININT + ININT, 0);
OUTIMAGE;
END;
END.
| Give a code snippet in #Simula
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tic-tac-toe | Tic-tac-toe |
Task
Play a game of tic-tac-toe.
Ensure that legal moves are played and that a winning position is notified.
Tic-tac-toe is also known as:
naughts and crosses
tic tac toe
tick tack toe
three in a row
tres en rayo and
Xs and Os
See also
MathWorld™, Tic-Tac-Toe game.
Wikipedi... | #Common_Lisp | Common Lisp |
(defun generate-board ()
(loop repeat 9 collect nil))
(defparameter *straights* '((1 2 3) (4 5 6) (7 8 9) (1 4 7) (2 5 8) (3 6 9) (1 5 9) (3 5 7)))
(defparameter *current-player* 'x)
(defun get-board-elt (n board)
(nth (1- n) board))
(defun legal-p (n board)
(null (get-board-elt n board)))
(defun set-bo... | Give a code snippet in #Common_Lisp
Task
Play a game of tic-tac-toe.
Ensure that legal moves are played and that a winning position is notified.
Tic-tac-toe is also known as:
naughts and crosses
tic tac toe
tick tack toe
three in a row
tres en rayo and
Xs and Os
See also
Math... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Convert | Non-decimal radices/Convert | Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in binary, but that's typically invisibl... | #AutoHotkey | AutoHotkey | MsgBox % number2base(200, 16) ; 12
MsgBox % parse(200, 16) ; 512
number2base(number, base)
{
While, base < digit := floor(number / base)
{
result := mod(number, base) . result
number := digit
}
result := digit . result
Return result
}
parse(number, base)
{
result = 0
pos := StrLen(number) - 1... | Give a code snippet in #AutoHotkey
Number base conversion is when you express a stored integer in an integer base, such as in octal (base 8) or binary (base 2). It also is involved when you take a string representing a number in a given base and convert it to the stored integer form. Normally, a stored integer is in b... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compound_data_type | Compound data type |
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.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
Related task
Enumeration
S... | #Kotlin | Kotlin | data class Point(var x: Int, var y: Int)
fun main(args: Array<String>) {
val p = Point(1, 2)
println(p)
p.x = 3
p.y = 4
println(p)
} | Give a code snippet in #Kotlin
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.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Delete_a_file | Delete a file | Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #PureBasic | PureBasic | DeleteFile("input.txt")
DeleteDirectory("docs","") ; needs to delete all included files
DeleteFile("/input.txt")
DeleteDirectory("/docs","*.*") ; deletes all files according to a pattern
DeleteDirectory("/docs","",#PB_FileSystem_Recursive) ; deletes all files and directories recursive | Give a code snippet in #PureBasic
Task
Delete a file called "input.txt" and delete a directory called "docs".
This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game/Solve | 24 game/Solve | task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| #Icon_and_Unicon | Icon and Unicon | invocable all
link strings # for csort, deletec, permutes
procedure main()
static eL
initial {
eoP := [] # set-up expression and operator permutation patterns
every ( e := !["a@b#c$d", "a@(b#c)$d", "a@b#(c$d)", "a@(b#c$d)", "a@(b#(c$d))"] ) &
( o := !(opers := "+-*/") || !opers || !opers ) do
... | Give a code snippet in #Icon_and_Unicon
task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Chowla_numbers | Chowla numbers | Chowla numbers are also known as:
Chowla's function
chowla numbers
the chowla function
the chowla number
the chowla sequence
The chowla number of n is (as defined by Chowla's function):
the sum of the divisors of n excluding unity and n
where n is a positive integer
The s... | #Perl | Perl | use strict;
use warnings;
use ntheory 'divisor_sum';
sub comma { reverse ((reverse shift) =~ s/(.{3})/$1,/gr) =~ s/^,//r }
sub chowla {
my($n) = @_;
$n < 2 ? 0 : divisor_sum($n) - ($n + 1);
}
sub prime_cnt {
my($n) = @_;
my $cnt = 1;
for (3..$n) {
$cnt++ if $_%2 and chowla($_) == 0
... | Give a code snippet in #Perl
Chowla numbers are also known as:
Chowla's function
chowla numbers
the chowla function
the chowla number
the chowla sequence
The chowla number of n is (as defined by Chowla's function):
the sum of the divisors of n excluding unity and n
where n ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Ada | Ada | -- Standard I/O Streams
with Ada.Integer_Text_Io;
procedure APlusB is
A, B : Integer;
begin
Ada.Integer_Text_Io.Get (Item => A);
Ada.Integer_Text_Io.Get (Item => B);
Ada.Integer_Text_Io.Put (A+B);
end APlusB; | Give a code snippet in #Ada
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Feigenbaum_constant_calculation | Feigenbaum constant calculation | Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| #Ring | Ring | # Project : Feigenbaum constant calculation
decimals(8)
see "Feigenbaum constant calculation:" + nl
maxIt = 13
maxItJ = 10
a1 = 1.0
a2 = 0.0
d1 = 3.2
see "i " + "d" + nl
for i = 2 to maxIt
a = a1 + (a1 - a2) / d1
for j = 1 to maxItJ
x = 0
y = 0
for k = 1 to pow(2,i)
... | Give a code snippet in #Ring
Task
Calculate the Feigenbaum constant.
See
Details in the Wikipedia article: Feigenbaum constant.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_a_foreign-language_function | Call a foreign-language function | Task
Show how a foreign language function can be called from the language.
As an example, consider calling functions defined in the C language. Create a string containing "Hello World!" of the string type typical to the language. Pass the string content to C's strdup. The content can be copied if necessary. Get the... | #Prolog | Prolog | :- module(plffi, [strdup/2]).
:- use_foreign_library(plffi). | Give a code snippet in #Prolog
Task
Show how a foreign language function can be called from the language.
As an example, consider calling functions defined in the C language. Create a string containing "Hello World!" of the string type typical to the language. Pass the string content to C's strdup. The content can... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CSV_data_manipulation | CSV data manipulation | CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file, change some values and save the cha... | #Nim | Nim | import strutils, streams
let
csv = newFileStream("data.csv", fmRead)
outf = newFileStream("data-out.csv", fmWrite)
var lineNumber = 1
while true:
if atEnd(csv):
break
var line = readLine(csv)
if lineNumber == 1:
line.add(",SUM")
else:
var sum = 0
for n in split(line, ","):
sum ... | Give a code snippet in #Nim
CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file, change... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/0-1 | Knapsack problem/0-1 | A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will have to last the whole day.
He cre... | #SQL | SQL |
WITH KnapsackItems (item, [weight], VALUE) AS
(
SELECT 'map',9, 150
UNION ALL SELECT 'compass',13, 35
UNION ALL SELECT 'water',153, 200
UNION ALL SELECT 'sandwich',50, 160
UNION ALL SELECT 'glucose',15, 60
UNION ALL SELECT 'tin',68, 45
UNION ALL SELECT 'banana',27, 60
... | Give a code snippet in #SQL
A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature, so he needs to pack well for the trip.
He has a good knapsack for carrying things, but knows that he can carry a maximum of only 4kg in it, and it will have t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #D | D | import std.stdio, std.algorithm, std.array, std.range;
T[] mergeSorted(T)(in T[] D) /*pure nothrow @safe*/ {
if (D.length < 2)
return D.dup;
return [D[0 .. $ / 2].mergeSorted, D[$ / 2 .. $].mergeSorted]
.nWayUnion.array;
}
void main() {
[3, 4, 2, 5, 1, 6].mergeSorted.writeln;
} | Give a code snippet in #D
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Circles_of_given_radius_through_two_points | Circles of given radius through two points |
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points.
Exceptions
r==0.0 should be treated as never describing circles (except in the case where the points are coincident).
If the points are coincident then an infinite number of circles with the point on thei... | #Sidef | Sidef | func circles(a, b, r) {
if (a == b) {
if (r == 0) {
return ['Degenerate point']
}
else {
return ['Infinitely many share a point']
}
}
var h = (b-a)/2
if (r**2 < h.norm) {
return ['Too far apart']
}
var l = sqrt(r**2 - h.norm... | Give a code snippet in #Sidef
Given two points on a plane and a radius, usually two circles of given radius can be drawn through the points.
Exceptions
r==0.0 should be treated as never describing circles (except in the case where the points are coincident).
If the points are coincident then an infinite number of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_duplicate_files | Find duplicate files | In a large directory structure it is easy to inadvertently leave unnecessary copies of files around, which can use considerable disk space and create confusion.
Task
Create a program which, given a minimum size and a folder/directory, will find all files of at least size bytes with duplicate contents under the dire... | #Python | Python | from __future__ import print_function
import os
import hashlib
import datetime
def FindDuplicateFiles(pth, minSize = 0, hashName = "md5"):
knownFiles = {}
#Analyse files
for root, dirs, files in os.walk(pth):
for fina in files:
fullFina = os.path.join(root, fina)
isSymLin... | Give a code snippet in #Python
In a large directory structure it is easy to inadvertently leave unnecessary copies of files around, which can use considerable disk space and create confusion.
Task
Create a program which, given a minimum size and a folder/directory, will find all files of at least size bytes with d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Untouchable_numbers | Untouchable numbers | Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also known as the aliquot sum.
A... | #Delphi | Delphi |
program Untouchable_numbers;
{$APPTYPE CONSOLE}
uses
System.SysUtils;
function SumDivisors(n: Integer): Integer;
begin
Result := 1;
var k := 2;
if not odd(n) then
k := 1;
var i := 1 + k;
while i * i <= n do
begin
if (n mod i) = 0 then
begin
inc(Result, i);
var j := n div i;... | Give a code snippet in #Delphi
Definitions
Untouchable numbers are also known as nonaliquot numbers.
An untouchable number is a positive integer that cannot be expressed as the sum of all the proper divisors of any positive integer. (From Wikipedia)
The sum of all the proper divisors is also kn... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #PureBasic | PureBasic | #SymbolCount = 12 ;0 based count
DataSection
denominations:
Data.s "M","CM","D","CD","C","XC","L","XL","X","IX","V","IV","I" ;0-12
denomValues:
Data.i 1000,900,500,400,100,90,50,40,10,9,5,4,1 ;values in decending sequential order
EndDataSection
;-setup
Structure romanNumeral
symbol.s
value.i
EndStruct... | Give a code snippet in #PureBasic
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #Slate | Slate | Platform run: 'ls'. | Give a code snippet in #Slate
Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| christopher/rosetta-code | |
http://rosettacode.org/wiki/ABC_problem | ABC problem | ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alphabet is guaranteed amongst all sid... | #Haskell | Haskell | import Data.List (delete)
import Data.Char (toUpper)
-- returns list of all solutions, each solution being a list of blocks
abc :: (Eq a) => [[a]] -> [a] -> [[[a]]]
abc _ [] = [[]]
abc blocks (c:cs) = [b:ans | b <- blocks, c `elem` b,
ans <- abc (delete b blocks) cs]
blocks = ["BO", "XK... | Give a code snippet in #Haskell
ABC problem
You are encouraged to solve this task according to the task description, using any language you may know.
You are given a collection of ABC blocks (maybe like the ones you had when you were a kid).
There are twenty blocks with two letters on each block.
A complete alpha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Metronome | Metronome |
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for production of the beat notes, and an ext... | #Wren | Wren | import "timer" for Timer
import "io" for Stdout
var metronome = Fn.new { |bpm, bpb, maxBeats|
var delay = (60000/bpm).floor
var beats = 0
while (true) {
Timer.sleep(delay)
System.write((beats % bpb == 0) ? "\n\aTICK " : "\atick ")
Stdout.flush()
beats = beats + 1
if... | Give a code snippet in #Wren
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for production... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #Apricot | Apricot | (puts "Hello world!") | Give a code snippet in #Apricot
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error... | christopher/rosetta-code | |
http://rosettacode.org/wiki/S-expressions | S-expressions | S-Expressions are one convenient way to parse and store data.
Task
Write a simple reader and writer for S-Expressions that handles quoted and unquoted strings, integers and floats.
The reader should read a single but nested S-Expression from a string and store it in a suitable datastructure (list, array, etc).
... | #Cowgol | Cowgol | include "cowgol.coh";
include "strings.coh";
include "malloc.coh";
const MAXDEPTH := 256; # Maximum depth (used for stack sizes)
const MAXSTR := 256; # Maximum string length
# Type markers
const T_ATOM := 1;
const T_STRING := 2;
const T_NUMBER := 3;
const T_LIST := 4;
# Value union
record SVal is
number @at... | Give a code snippet in #Cowgol
S-Expressions are one convenient way to parse and store data.
Task
Write a simple reader and writer for S-Expressions that handles quoted and unquoted strings, integers and floats.
The reader should read a single but nested S-Expression from a string and store it in a suitable dat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #D | D | void main()
{
import std.algorithm.searching : maxElement;
import std.stdio : writeln;
[9, 4, 3, 8, 5].maxElement.writeln;
} | Give a code snippet in #D
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Case-sensitivity_of_identifiers | Case-sensitivity of identifiers | Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, Samba and Bernie.
For a language... | #Elixir | Elixir | dog = "Benjamin"
doG = "Samba"
dOG = "Bernie"
IO.puts "The three dogs are named #{dog}, #{doG} and #{dOG}." | Give a code snippet in #Elixir
Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, S... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #DeviousYarn | DeviousYarn | o:"Hello world! | Give a code snippet in #DeviousYarn
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hailstone_sequence | Hailstone sequence | The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) + 1
The (unproven) Collatz conje... | #Burlesque | Burlesque |
blsq ) 27{^^^^2.%{3.*1.+}\/{2./}\/ie}{1!=}w!bx{\/+]}{\/isn!}w!L[
112
| Give a code snippet in #Burlesque
The Hailstone sequence of numbers can be generated from a starting positive integer, n by:
If n is 1 then the sequence ends.
If n is even then the next n of the sequence = n/2
If n is odd then the next n of the sequence = (3 * n) ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Pythagorean_means | Averages/Pythagorean means | Task[edit]
Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive).
Show that
A
(
x
1
,
…
,
x
n
)
≥
G
(
x
1
,
…
,
x
n
)
≥
H
(
x
1
,
…
,
x
n
)
{\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{1},\ldots ,x_{n})}
for this set of p... | #CoffeeScript | CoffeeScript | a = [ 1..10 ]
arithmetic_mean = (a) -> a.reduce(((s, x) -> s + x), 0) / a.length
geometic_mean = (a) -> Math.pow(a.reduce(((s, x) -> s * x), 1), (1 / a.length))
harmonic_mean = (a) -> a.length / a.reduce(((s, x) -> s + 1 / x), 0)
A = arithmetic_mean a
G = geometic_mean a
H = harmonic_mean a
console.log "A = ", A, "... | Give a code snippet in #CoffeeScript
Task[edit]
Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive).
Show that
A
(
x
1
,
…
,
x
n
)
≥
G
(
x
1
,
…
,
x
n
)
≥
H
(
x
1
,
…
,
x
n
)
{\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #Sather | Sather | class MAIN is
-- we cannot have "functions" (methods) outside classes
mult(a, b:FLT):FLT is return a*b; end;
main is
#OUT + mult(5.2, 3.4) + "\n";
end;
end; | Give a code snippet in #Sather
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Start_from_a_main_routine | Start from a main routine |
Some languages (like Gambas and Visual Basic) support two startup modes. Applications written in these languages start with an open window that waits for events, and it is necessary to do some trickery to cause a main procedure to run instead. Data driven or event driven languages may also require similar tricker... | #Wren | Wren | var main = Fn.new {
System.print("Hello from the main function.")
}
main.call() | Give a code snippet in #Wren
Some languages (like Gambas and Visual Basic) support two startup modes. Applications written in these languages start with an open window that waits for events, and it is necessary to do some trickery to cause a main procedure to run instead. Data driven or event driven languages ma... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Output | Non-decimal radices/Output | Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routines of your programming langu... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
const proc: main is func
local
var integer: i is 0;
begin
for i range 1 to 33 do
writeln(i lpad 6 <&
i radix 8 lpad 6 <&
i radix 16 lpad 6);
end for;
end func; | Give a code snippet in #Seed7
Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard rou... | christopher/rosetta-code | |
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}}
] | Give a code snippet in #Mathematica.2FWolfram_Language
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 int... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Scala | Scala | def ack(m: BigInt, n: BigInt): BigInt = {
if (m==0) n+1
else if (n==0) ack(m-1, 1)
else ack(m-1, ack(m, n-1))
} | Give a code snippet in #Scala
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_format | Date format | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| #Terraform | Terraform | locals {
today = timestamp()
}
output "iso" {
value = formatdate("YYYY-MM-DD", local.today)
}
output "us-long" {
value = formatdate("EEEE, MMMM D, YYYY", local.today)
} | Give a code snippet in #Terraform
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Ordered_partitions | Ordered partitions | In this task we want to find the ordered partitions into fixed-size blocks.
This task is related to Combinations in that it has to do with discrete mathematics and moreover a helper function to compute combinations is (probably) needed to solve this task.
p
a
r
t
i
t
i
o
n
s
(
a
r
g
1
,
a
r
g
2
,
... | #C.2B.2B | C++ |
#include <iostream>
#include <algorithm>
#include <vector>
#include <numeric>
void partitions(std::vector<size_t> args) {
size_t sum = std::accumulate(std::begin(args), std::end(args), 0);
std::vector<size_t> nums(sum);
std::iota(std::begin(nums), std::end(nums), 1);
do {
size_t total_index = 0;
std... | Give a code snippet in #C.2B.2B
In this task we want to find the ordered partitions into fixed-size blocks.
This task is related to Combinations in that it has to do with discrete mathematics and moreover a helper function to compute combinations is (probably) needed to solve this task.
p
a
r
t
i
t
i
o
n
s
(
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop b... | #11l | 11l | L(i) (1..9).step(2)
print(i) | Give a code snippet in #11l
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Incre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pascal%27s_triangle/Puzzle | Pascal's triangle/Puzzle | This puzzle involves a Pascals Triangle, also known as a Pyramid of Numbers.
[ 151]
[ ][ ]
[40][ ][ ]
[ ][ ][ ][ ]
[ X][11][ Y][ 4][ Z]
Each brick of the pyramid is the sum of the two bricks situated below it.
Of the three missing numbers at the base of the pyramid,
the... | #Sidef | Sidef | # set up triangle
var rows = 5
var tri = rows.of {|i| (i+1).of { Hash(x => 0, z => 0, v => 0, rhs => nil) } }
tri[0][0]{:rhs} = 151
tri[2][0]{:rhs} = 40
tri[4][0]{:x} = 1
tri[4][1]{:v} = 11
tri[4][2]{:x} = 1
tri[4][2]{:z} = 1
tri[4][3]{:v} = 4
tri[4][4]{:z} = 1
# aggregate from bottom to top
for row in (tri.len ^.. 1... | Give a code snippet in #Sidef
This puzzle involves a Pascals Triangle, also known as a Pyramid of Numbers.
[ 151]
[ ][ ]
[40][ ][ ]
[ ][ ][ ][ ]
[ X][11][ Y][ 4][ Z]
Each brick of the pyramid is the sum of the two bricks situated below it.
Of the three missing numbers ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bubble_sort | Sorting algorithms/Bubble sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #PicoLisp | PicoLisp | (de bubbleSort (Lst)
(use Chg
(loop
(off Chg)
(for (L Lst (cdr L) (cdr L))
(when (> (car L) (cadr L))
(xchg L (cdr L))
(on Chg) ) )
(NIL Chg Lst) ) ) ) | Give a code snippet in #PicoLisp
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Babbage_problem | Babbage problem |
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Computers, second edition, 1970, p.... | #XLISP | XLISP | ; The computer will evaluate expressions written in -- possibly nested -- parentheses, where the first symbol gives the operation and any subsequent symbols or numbers give the operands.
; For instance, (+ (+ 2 2) (- 7 5)) evaluates to 6.
; We define our problem as a function:
(define (try n)
; We are looking f... | Give a code snippet in #XLISP
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Comp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Wrong_ranges | Loops/Wrong ranges | Loops/Wrong ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages have syntax or function(s) to generate a range of numeric values from a start value, a stop value, and an increment.
The purpose of this task is to select the range syntax/functi... | #Haskell | Haskell | import Data.List
main = putStrLn $ showTable True '|' '-' '+' table
table = [["start","stop","increment","Comment","Code","Result/Analysis"]
,["-2","2","1","Normal","[-2,-1..2] or [-2..2]",show [-2,-1..2]]
,["-2","2","0","Zero increment","[-2,-2..2]","Infinite loop of -2 <=> repeat -2"]
,["-... | Give a code snippet in #Haskell
Loops/Wrong ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages have syntax or function(s) to generate a range of numeric values from a start value, a stop value, and an increment.
The purpose of this task is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Animation | Animation |
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task demonstrates this.
Task
Creat... | #Fantom | Fantom |
using concurrent
using fwt
using gfx
const class RotateString : Actor
{
new make (Label label) : super (ActorPool ())
{
Actor.locals["rotate-label"] = label
Actor.locals["rotate-string"] = label.text
Actor.locals["direction"] = "forward"
sendLater (1sec, "update")
}
// responsible for call... | Give a code snippet in #Fantom
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop b... | #Haskell | Haskell | import Control.Monad (forM_)
main = do forM_ [2,4..8] (\x -> putStr (show x ++ ", "))
putStrLn "who do we appreciate?" | Give a code snippet in #Haskell
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/I... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game | 24 game | The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digits, used exactly once each. T... | #Vlang | Vlang | import os
import rand
import rand.seed
import math
fn main() {
rand.seed(seed.time_seed_array(2))
mut n := []int{len: 4}
for i in 0.. n.len {
n[i] = rand.intn(9) or {0}
}
println("Your numbers: $n")
expr := os.input("Enter RPN: ")
if expr.len != 7 {
println("invalid. expres... | Give a code snippet in #Vlang
The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four di... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Nim | Nim | var a {.noInit.}: array[1_000_000, int]
# For a proc, {.noInit.} means that the result is not initialized.
proc p(): array[1000, int] {.noInit.} =
for i in 0..999: result[i] = i | Give a code snippet in #Nim
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Humble_numbers | Humble numbers | Humble numbers are positive integers which have no prime factors > 7.
Humble numbers are also called 7-smooth numbers, and sometimes called highly composite,
although this conflicts with another meaning of highly composite numbers.
Another way to express the above is:
humble = 2i × 3j × 5k... | #Kotlin | Kotlin | fun isHumble(i: Int): Boolean {
if (i <= 1) return true
if (i % 2 == 0) return isHumble(i / 2)
if (i % 3 == 0) return isHumble(i / 3)
if (i % 5 == 0) return isHumble(i / 5)
if (i % 7 == 0) return isHumble(i / 7)
return false
}
fun main() {
val limit: Int = Short.MAX_VALUE.toInt()
val h... | Give a code snippet in #Kotlin
Humble numbers are positive integers which have no prime factors > 7.
Humble numbers are also called 7-smooth numbers, and sometimes called highly composite,
although this conflicts with another meaning of highly composite numbers.
Another way to express the abov... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers | Catalan numbers | Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
for
n
≥
0.
{\displaystyle C... | #Perl | Perl | sub factorial { my $f = 1; $f *= $_ for 2 .. $_[0]; $f; }
sub catalan {
my $n = shift;
factorial(2*$n) / factorial($n+1) / factorial($n);
}
print "$_\t@{[ catalan($_) ]}\n" for 0 .. 20; | Give a code snippet in #Perl
Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calculating_the_value_of_e | Calculating the value of e | Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| #Icon_and_Unicon | Icon and Unicon | $define EPSILON 1.0e-15
procedure main()
local e0
local e := 2.0
local fact := 1
local n := 2
repeat {
e0 := e
fact *:= n
n +:= 1
e +:= (1.0 / fact)
if abs(e - e0) < EPSILON then break
}
write("computed e ", e)
write("keyword &e ", &e)
end | Give a code snippet in #Icon_and_Unicon
Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_stability | Sort stability |
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
... | #D.C3.A9j.C3.A0_Vu | Déjà Vu | cities = [ {"UK", "London"},
{"US", "New York"},
{"US", "Birmingham"},
{"UK", "Birmingham"} ]
IO.inspect Enum.sort(cities)
IO.inspect Enum.sort(cities, fn a,b -> elem(a,0) >= elem(b,0) end)
IO.inspect Enum.sort_by(cities, fn {country, _city} -> country end)
IO.inspect Enum.sort_by(cit... | Give a code snippet in #D.C3.A9j.C3.A0_Vu
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 sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available,... | #HicEst | HicEst | REAL :: n = 3, Astat(n), Bdyn(1, 1)
Astat(2) = 2.22222222
WRITE(Messagebox, Name) Astat(2)
ALLOCATE(Bdyn, 2*n, 3*n)
Bdyn(n-1, n) = -123
WRITE(Row=27) Bdyn(n-1, n)
ALIAS(Astat, n-1, last2ofAstat, 2)
WRITE(ClipBoard) last2ofAstat ! 2.22222222 0 | Give a code snippet in #HicEst
This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Multiple | Inheritance/Multiple | Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePhone, then write a class Camer... | #Ruby | Ruby | module Camera
# define methods here
end
class MobilePhone
# define methods here
end
class CameraPhone < MobilePhone
include Camera
# define methods here
end | Give a code snippet in #Ruby
Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePho... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_input_device_is_a_terminal | Check input device is a terminal | Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| #Haskell | Haskell | module Main (main) where
import System.Posix.IO (stdInput)
import System.Posix.Terminal (queryTerminal)
main :: IO ()
main = do
isTTY <- queryTerminal stdInput
putStrLn $ if isTTY
then "stdin is TTY"
else "stdin is not TTY" | Give a code snippet in #Haskell
Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Maximum_triangle_path_sum | Maximum triangle path sum | Starting from the top of a pyramid of numbers like this, you can walk down going one step on the right or on the left, until you reach the bottom row:
55
94 48
95 30 96
77 71 26 67
One of such walks is 55 - 94 - 30 - 26.
You... | #AutoHotkey | AutoHotkey | Give a code snippet in #AutoHotkey
Starting from the top of a pyramid of numbers like this, you can walk down going one step on the right or on the left, until you reach the bottom row:
55
94 48
95 30 96
77 71 26 67
One of ... | christopher/rosetta-code | ||
http://rosettacode.org/wiki/Matrix_multiplication | Matrix multiplication | Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| #Julia | Julia | julia> [1 2 3 ; 4 5 6] * [1 2 ; 3 4 ; 5 6] # product of a 2x3 by a 3x2
2x2 Array{Int64,2}:
22 28
49 64
julia> [1 2 3] * [1,2,3] # product of a row vector by a column vector
1-element Array{Int64,1}:
14
| Give a code snippet in #Julia
Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Symmetric_difference | Symmetric difference | Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{\displaystyle (A\cup B)\setminus (A... | #Ksh | Ksh |
#!/bin/ksh
# Symmetric difference - enumerate the items that are in A or B but not both.
# # Variables:
#
typeset -a A=( John Bob Mary Serena )
typeset -a B=( Jim Mary John Bob )
# # Functions:
#
# # Function _flattenarr(arr, sep) - flatten arr into string by separator sep
#
function _flattenarr {
typeset _arr... | Give a code snippet in #Ksh
Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{\displ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Secure_temporary_file | Secure temporary file | Task
Create a temporary file, securely and exclusively (opening it such that there are no possible race conditions).
It's fine assuming local filesystem semantics (NFS or other networking filesystems can have signficantly more complicated semantics for satisfying the "no race conditions" criteria).
The function shou... | #Emacs_Lisp | Emacs Lisp | (make-temp-file "prefix")
;; => "/tmp/prefix25452LPe" | Give a code snippet in #Emacs_Lisp
Task
Create a temporary file, securely and exclusively (opening it such that there are no possible race conditions).
It's fine assuming local filesystem semantics (NFS or other networking filesystems can have signficantly more complicated semantics for satisfying the "no race condi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_intersection_of_a_line_with_a_plane | Find the intersection of a line with a plane | Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of (0, 0, 1) and which passes ... | #C.23 | C# | using System;
namespace FindIntersection {
class Vector3D {
private double x, y, z;
public Vector3D(double x, double y, double z) {
this.x = x;
this.y = y;
this.z = z;
}
public static Vector3D operator +(Vector3D lhs, Vector3D rhs) {
... | Give a code snippet in #C.23
Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Gnome_sort | Sorting algorithms/Gnome sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #PARI.2FGP | PARI/GP | gnomeSort(v)={
my(i=2,j=3,n=#v,t);
while(i<=n,
if(v[i-1]>v[i],
t=v[i];
v[i]=v[i-1];
v[i--]=t;
if(i==1, i=j; j++);
,
i=j;
j++
)
);
v
}; | Give a code snippet in #PARI.2FGP
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 |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/List_comprehensions | List comprehensions | A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and the use of map and filter functio... | #Ioke | Ioke | for(
x <- 1..20,
y <- x..20,
z <- y..20,
x * x + y * y == z * z,
[x, y, z]
) | Give a code snippet in #Ioke
A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mandelbrot_set | Mandelbrot set | Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
| #JavaScript | JavaScript | function mandelIter(cx, cy, maxIter) {
var x = 0.0;
var y = 0.0;
var xx = 0;
var yy = 0;
var xy = 0;
var i = maxIter;
while (i-- && xx + yy <= 4) {
xy = x * y;
xx = x * x;
yy = y * y;
x = xx - yy + cx;
y = xy + xy + cy;
}
return maxIter - i;
}
function mandelbrot(canvas, xmin, ... | Give a code snippet in #JavaScript
Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program pancakeSort.s */
/* REMARK 1 : this program use routines in a include file
see task Include a file language arm assembly
for the routine affichageMess conversion10
see at end of this program the instruction include */
/* for constantes see task include a fi... | Give a code snippet in #ARM_Assembly
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Q... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_if_a_point_is_within_a_triangle | Find if a point is within a triangle | Find if a point is within a triangle.
Task
Assume points are on a plane defined by (x, y) real number coordinates.
Given a point P(x, y) and a triangle formed by points A, B, and C, determine if P is within triangle ABC.
You may use any algorithm.
Bonus: explain why the algorithm you chose works.
Re... | #Nim | Nim | import strformat
const
Eps = 0.001
Eps2 = Eps * Eps
type
Point = tuple[x, y: float]
Triangle = object
p1, p2, p3: Point
func initTriangle(p1, p2, p3: Point): Triangle =
Triangle(p1: p1, p2: p2, p3: p3)
func side(p1, p2, p: Point): float =
(p2.y - p1.y) * (p.x - p1.x) + (-p2.x + p1.x) * (p.y - ... | Give a code snippet in #Nim
Find if a point is within a triangle.
Task
Assume points are on a plane defined by (x, y) real number coordinates.
Given a point P(x, y) and a triangle formed by points A, B, and C, determine if P is within triangle ABC.
You may use any algorithm.
Bonus: explain why the al... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Chowla_numbers | Chowla numbers | Chowla numbers are also known as:
Chowla's function
chowla numbers
the chowla function
the chowla number
the chowla sequence
The chowla number of n is (as defined by Chowla's function):
the sum of the divisors of n excluding unity and n
where n is a positive integer
The s... | #11l | 11l | F chowla(n)
V sum = 0
V i = 2
L i * i <= n
I n % i == 0
sum += i
V j = n I/ i
I i != j
sum += j
i++
R sum
L(n) 1..37
print(‘chowla(’n‘) = ’chowla(n))
V count = 0
V power = 100
L(n) 2..10'000'000
I chowla(n) == 0
count++
I n % power == 0
... | Give a code snippet in #11l
Chowla numbers are also known as:
Chowla's function
chowla numbers
the chowla function
the chowla number
the chowla sequence
The chowla number of n is (as defined by Chowla's function):
the sum of the divisors of n excluding unity and n
where n ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #Standard_ML | Standard ML | fun hanoi(0, a, b, c) = [] |
hanoi(n, a, b, c) = hanoi(n-1, a, c, b) @ [(a,b)] @ hanoi(n-1, c, b, a);
| Give a code snippet in #Standard_ML
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available,... | #BaCon | BaCon |
DATA "January", "February", "March", "April", "May", "June", "July"
DATA "August", "September", "October", "November", "December"
LOCAL dat$[11]
FOR i = 0 TO 11
READ dat$[i]
PRINT dat$[i]
NEXT
| Give a code snippet in #BaCon
This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Runge-Kutta_method | Runge-Kutta method | Given the example Differential equation:
y
′
(
t
)
=
t
×
y
(
t
)
{\displaystyle y'(t)=t\times {\sqrt {y(t)}}}
With initial condition:
t
0
=
0
{\displaystyle t_{0}=0}
and
y
0
=
y
(
t
0
)
=
y
(
0
)
=
1
{\displaystyle y_{0}=y(t_{0})=y(0)=1}
This equation has an exact solution:
... | #Groovy | Groovy |
class Runge_Kutta{
static void main(String[] args){
def y=1.0,t=0.0,counter=0;
def dy1,dy2,dy3,dy4;
def real;
while(t<=10)
{if(counter%10==0)
{real=(t*t+4)*(t*t+4)/16;
println("y("+t+")="+ y+ " Error:"+ (real-y));
}
dy1=dy(dery(y,t));
dy2=dy(dery(y+dy1/2,t+0.05));
dy3=dy(dery(y+dy2/2,t+0.05));
dy4=dy(dery(y+dy3,t+0... | Give a code snippet in #Groovy
Given the example Differential equation:
y
′
(
t
)
=
t
×
y
(
t
)
{\displaystyle y'(t)=t\times {\sqrt {y(t)}}}
With initial condition:
t
0
=
0
{\displaystyle t_{0}=0}
and
y
0
=
y
(
t
0
)
=
y
(
0
)
=
1
{\displaystyle y_{0}=y(t_{0})=y(0)=1}
This e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_a_quadratic_function | Roots of a quadratic function | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your program must correctly handle n... | #ERRE | ERRE | PROGRAM QUADRATIC
PROCEDURE SOLVE_QUADRATIC
D=B*B-4*A*C
IF ABS(D)<1D-6 THEN D=0 END IF
CASE SGN(D) OF
0->
PRINT("the single root is ";-B/2/A)
END ->
1->
F=(1+SQR(1-4*A*C/(B*B)))/2
PRINT("the real roots are ";-F*B/A;"and ";-C/B/F)
END ->
-1->
PRINT("the complex roo... | Give a code snippet in #ERRE
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pangram_checker | Pangram checker | Pangram checker
You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.
For example: The quick brown fox jumps over the lazy dog.
Task
Write a function or method to chec... | #Picat | Picat | go =>
S1 = "The quick brown fox jumps over the lazy dog",
S2 = "The slow brown fox jumps over the lazy dog",
println([S1, is_pangram(S1)]),
println([S2, is_pangram(S2)]),
nl,
println("With missing chars:"),
println([S1, is_pangram2(S1)]),
println([S2, is_pangram2(S2)]),
nl.
% Check if S ... | Give a code snippet in #Picat
Pangram checker
You are encouraged to solve this task according to the task description, using any language you may know.
A pangram is a sentence that contains all the letters of the English alphabet at least once.
For example: The quick brown fox jumps over the lazy dog.
Task
Wri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #R | R | stringval <- readline("String: ")
intval <- as.integer(readline("Integer: ")) | Give a code snippet in #R
User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Compiler/syntax_analyzer | Compiler/syntax analyzer | A Syntax analyzer transforms a token stream (from the Lexical analyzer)
into a Syntax tree, based on a grammar.
Task[edit]
Take the output from the Lexical analyzer task,
and convert it to an Abstract Syntax Tree (AST),
based on the grammar below. The output should be in a flattened format.
The program should read in... | #Icon | Icon | #
# The Rosetta Code Tiny-Language Parser, in Icon.
#
# This implementation is based closely on the pseudocode and the C
# reference implementation.
#
# ximage from the IPL is useful for debugging. Use "xdump(x)" to
# pretty-print x.
#link ximage
record token_record (line_no, column_no, tok, tokval)
record token_ge... | Give a code snippet in #Icon
A Syntax analyzer transforms a token stream (from the Lexical analyzer)
into a Syntax tree, based on a grammar.
Task[edit]
Take the output from the Lexical analyzer task,
and convert it to an Abstract Syntax Tree (AST),
based on the grammar below. The output should be in a flattened forma... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Monads/List_monad | Monads/List monad | A Monad is a combination of a data-type with two helper functions written for that type.
The data-type can be of any kind which can contain values of some other type – common examples are lists, records, sum-types, even functions or IO streams. The two special functions, mathematically known as eta and mu, but usually... | #uBasic.2F4tH | uBasic/4tH | s := "[" : Push 5, 4, 3
Do While Used ()
y = Set (x, Pop ()) + 1
s = Join (s, Str (Set (z, y * 2)), ", " )
Loop
Print Show (Set (s, Join (Clip (s, 2), "]")))
| Give a code snippet in #uBasic.2F4tH
A Monad is a combination of a data-type with two helper functions written for that type.
The data-type can be of any kind which can contain values of some other type – common examples are lists, records, sum-types, even functions or IO streams. The two special functions, mathemati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_8-ball | Magic 8-ball | Task
Create Magic 8-Ball.
See details at: Magic 8-Ball.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurren... | #Haskell | Haskell | import System.Random (getStdRandom, randomR)
import Control.Monad (forever)
answers :: [String]
answers =
[ "It is certain"
, "It is decidedly so"
, "Without a doubt"
, "Yes, definitely"
, "You may rely on it"
, "As I see it, yes"
, "Most likely"
, "Outlook good"
, "Signs point t... | Give a code snippet in #Haskell
Task
Create Magic 8-Ball.
See details at: Magic 8-Ball.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinfor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knight%27s_tour | Knight's tour |
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; that is, the knight need not e... | #ATS | ATS | (*
Find Knight’s Tours.
Using Warnsdorff’s heuristic, find multiple solutions.
Optionally accept only closed tours.
Compile with:
patscc -O3 -DATS_MEMALLOC_GCBDW -o knights_tour knights_tour.dats -lgc
Usage: ./knights_tour [START_POSITION [MAX_TOURS [closed]]]
Examples:
./knights_tour ... | Give a code snippet in #ATS
Task
Problem: you have a standard 8x8 chessboard, empty but for a single knight on some square. Your task is to emit a series of legal knight moves that result in the knight visiting every square on the chessboard exactly once. Note that it is not a requirement that the tour be "closed"; t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_HTML_table | Create an HTML table | Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled with sequential row numbers.
The... | #JavaScript | JavaScript | <html><head><title>Table maker</title><script type="application/javascript">
// normally, don't do this: at least name it something other than "a"
Node.prototype.a = function (e) { this.appendChild(e); return this }
function ce(tag, txt) {
var x = document.createElement(tag);
x.textContent = (txt === undefined) ?... | Give a code snippet in #JavaScript
Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is fille... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/String | Literals/String | Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters
Here document
Other tasks r... | #TUSCRIPT | TUSCRIPT |
$$ MODE TUSCRIPT,{}
s1=*
DATA "string"
s2=*
DATA + "double" quotes
s3=*
DATA + 'single' quotes
s4=*
DATA + "double" + 'single' quotes
show=JOIN(s1," ",s2,s3,s4)
show=JOIN(show)
PRINT show
| Give a code snippet in #TUSCRIPT
Task
Show literal specification of characters and strings.
If supported, show how the following work:
verbatim strings (quotes where escape sequences are quoted literally)
here-strings
Also, discuss which quotes expand variables.
Related tasks
Special characters... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sieve_of_Eratosthenes | Sieve of Eratosthenes | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed... | #Modula-2 | Modula-2 | MODULE Erato;
FROM InOut IMPORT WriteCard, WriteLn;
FROM MathLib IMPORT sqrt;
CONST Max = 100;
VAR prime: ARRAY [2..Max] OF BOOLEAN;
i: CARDINAL;
PROCEDURE Sieve;
VAR i, j, sqmax: CARDINAL;
BEGIN
sqmax := TRUNC(sqrt(FLOAT(Max)));
FOR i := 2 TO Max DO prime[i] := TRUE; END;
FOR i := 2 TO sqm... | Give a code snippet in #Modula-2
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Foreach | Loops/Foreach | Loop through and print each element in a collection in order.
Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for... | #PHL | PHL | var numbers = 1..10;
numbers each # (number) [
printf("%i\n", number);
]; | Give a code snippet in #PHL
Loop through and print each element in a collection in order.
Use your language's "for each" loop if it has one, otherwise iterate through the collection in order with some other loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/D... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Keyboard_input/Flush_the_keyboard_buffer | Keyboard input/Flush the keyboard buffer | Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| #Haskell | Haskell | import Control.Concurrent (threadDelay)
import Control.Monad (when)
import System.IO (hFlush, stdout)
import System.Posix
-- If the file descriptor is associated with a terminal, then flush its input,
-- otherwise do nothing.
termFlush :: Fd -> IO ()
termFlush fd = do
isTerm <- queryTerminal fd
when isTerm $ disc... | Give a code snippet in #Haskell
Flush the keyboard buffer.
This reads characters from the keyboard input and
discards them until there are no more currently buffered,
and then allows the program to continue.
The program must not wait for users to type anything.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Inverted_syntax | Inverted syntax | Inverted syntax with conditional expressions
In traditional syntax conditional expressions are usually shown before the action within a statement or code block:
IF raining=true THEN needumbrella=true
In inverted syntax, the action is listed before the conditional expression in the statement or code block:
needumb... | #Oforth | Oforth | 6 -> a : Push 6 on the stack and set the top of the stack as value of local variable a (top of the stack is consumed)
6 := a : Push 6 on the stack and set the top of the satck as value of attribute a (top of the stack is consumed).
raining ifTrue: [ true ->needumbrella ]
| Give a code snippet in #Oforth
Inverted syntax with conditional expressions
In traditional syntax conditional expressions are usually shown before the action within a statement or code block:
IF raining=true THEN needumbrella=true
In inverted syntax, the action is listed before the conditional expression in the st... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Environment_variables | Environment variables | Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| #M2000_Interpreter | M2000 Interpreter |
Module CheckIt {
\\ using read only variablles
Print "Platform: ";Platform$
Print "Computer Os: "; Os$
Print "Type of OS: ";OsBit;" bit"
Print "Computer Name:"; Computer$
Print "User Name: "; User.Name$
\\ using WScript.Shell
Declare objShell "WScript.Shell"
With... | Give a code snippet in #M2000_Interpreter
Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers | Luhn test of credit card numbers | The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order of the digits in the number.
Tak... | #Logo | Logo | to small? :list
output or [empty? :list] [empty? bf :list]
end
to every.other :list
if small? :list [output :list]
output fput first :list every.other bf bf :list
end
to wordtolist :word
output map.se [?] :word
end
to double.digit :digit
output item :digit {0 2 4 6 8 1 3 5 7 9}@0
; output ifelse :digit < ... | Give a code snippet in #Logo
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Interactive_programming_(repl) | Interactive programming (repl) | Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
Task
Show how to start this... | #Elena | Elena |
c:\Alex\ELENA\bin>elt
ELENA command line VM terminal 5.1.13 (C)2011-2020 by Alexei Rakov
ELENA VM 5.1.17 (C)2005-2020 by Alex Rakov
Initializing...
Done...
>f(s1,s2,sep){^ s1 + sep + sep + s2 };
>f("Rosetta","Code",":")
Rosetta::Code
>
| Give a code snippet in #Elena
Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Box_the_compass | Box the compass | There be many a land lubber that knows naught of the pirate ways and gives direction by degree!
They know not how to box the compass!
Task description
Create a function that takes a heading in degrees and returns the correct 32-point compass heading.
Use the function to print and display a table of Index, Compass... | #Sidef | Sidef | func point (index) {
var ix = (index % 32);
if (ix & 1) { "#{point((ix + 1) & 28)} by #{point(((2 - (ix & 2)) * 4) + ix & 24)}" }
elsif (ix & 2) { "#{point((ix + 2) & 24)}-#{point((ix | 4) & 28)}" }
elsif (ix & 4) { "#{point((ix + 8) & 16)}#{point((ix | 8) & 24)}" }
else { <north east s... | Give a code snippet in #Sidef
There be many a land lubber that knows naught of the pirate ways and gives direction by degree!
They know not how to box the compass!
Task description
Create a function that takes a heading in degrees and returns the correct 32-point compass heading.
Use the function to print and di... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Farey_sequence | Farey sequence | The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a Farey series.
Each Farey se... | #Maple | Maple | #Displays terms in Farey_sequence of order n
farey_sequence := proc(n)
local a,b,c,d,k;
a,b,c,d := 0,1,1,n;
printf("%d/%d", a,b);
while c <= n do
k := iquo(n+b,d);
a,b,c,d := c,d,c*k-a,d*k-b;
printf(", %d/%d", a,b)
end do;
printf("\n");
end proc:
#Returns the length of a Farey sequence
farey_l... | Give a code snippet in #Maple
The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multifactorial | Multifactorial | The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(... | #Julia | Julia | using Printf
function multifact(n::Integer, k::Integer)
n > 0 && k > 0 || throw(DomainError())
k > 1 || factorial(n)
return prod(n:-k:2)
end
const khi = 5
const nhi = 10
println("Showing multifactorial for n in [1, $nhi] and k in [1, $khi].")
for k = 1:khi
a = multifact.(1:nhi, k)
lab = "n" * "!... | Give a code snippet in #Julia
The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\dis... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_manipulation | Date manipulation | Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| #Julia | Julia | using Dates
function main()
dtstr = "March 7 2009 7:30pm" # Base.Dates doesn't handle "EST"
cleandtstr = replace(dtstr, r"(am|pm)"i, "")
dtformat = dateformat"U dd yyyy HH:MM"
dtime = parse(DateTime, cleandtstr, dtformat) +
Hour(12 * contains(dtstr, r"pm"i)) # add 12h for the pm
println(Da... | Give a code snippet in #Julia
Task
Given the date string "March 7 2009 7:30pm EST",
output the time 12 hours later in any human-readable format.
As extra credit, display the resulting time in a time zone different from your own.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix_transposition | Matrix transposition | Transpose an arbitrarily sized rectangular Matrix.
| #Wren | Wren | import "/matrix" for Matrix
import "/fmt" for Fmt
var m = Matrix.new([
[ 1, 2, 3],
[ 4, 5, 6],
[ 7, 8, 9],
[10, 11, 12]
])
System.print("Original:\n")
Fmt.mprint(m, 2, 0)
System.print("\nTransposed:\n")
Fmt.mprint(m.transpose, 2, 0) | Give a code snippet in #Wren
Transpose an arbitrarily sized rectangular Matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Superellipse | Superellipse | A superellipse is a geometric figure defined as the set of all points (x, y) with
|
x
a
|
n
+
|
y
b
|
n
=
1
,
{\displaystyle \left|{\frac {x}{a}}\right|^{n}\!+\left|{\frac {y}{b}}\right|^{n}\!=1,}
where n, a, and b are positive numbers.
Task
Draw a superellipse with n = 2.5, and a... | #Scala | Scala | import java.awt._
import java.awt.geom.Path2D
import java.util
import javax.swing._
import javax.swing.event.{ChangeEvent, ChangeListener}
object SuperEllipse extends App {
SwingUtilities.invokeLater(() => {
new JFrame("Super Ellipse") {
class SuperEllipse extends JPanel with ChangeListener {
... | Give a code snippet in #Scala
A superellipse is a geometric figure defined as the set of all points (x, y) with
|
x
a
|
n
+
|
y
b
|
n
=
1
,
{\displaystyle \left|{\frac {x}{a}}\right|^{n}\!+\left|{\frac {y}{b}}\right|^{n}\!=1,}
where n, a, and b are positive numbers.
Task
Draw a s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_year | Long year | Most years have 52 weeks, some have 53, according to ISO8601.
Task
Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
| #Delphi | Delphi |
program Long_year;
{$APPTYPE CONSOLE}
{$R *.res}
uses
System.SysUtils;
function p(const Year: Integer): Integer;
begin
Result := (Year + (Year div 4) - (Year div 100) + (Year div 400)) mod 7;
end;
function IsLongYear(const Year: Integer): Boolean;
begin
Result := (p(Year) = 4) or (p(Year - 1) = 3);
en... | Give a code snippet in #Delphi
Most years have 52 weeks, some have 53, according to ISO8601.
Task
Write a function which determines if a given year is long (53 weeks) or not, and demonstrate it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Get_system_command_output | Get system command output | Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| #Racket | Racket | #lang racket/base
(require racket/system
(only-in racket/port with-output-to-string)
tests/eli-tester)
(test
;; system runs command and outputs to current output port (which is stdout unless we catch it)
(system "ls /etc/motd") => #t
;; it throws an error on non-zero exit code (so I need to cat... | Give a code snippet in #Racket
Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| christopher/rosetta-code |
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