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
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|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Associative_array/Creation | Associative array/Creation | Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element ins... | #XLISP | XLISP | (define starlings (make-table)) | Give a code snippet in #XLISP
Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determinant_and_permanent | Determinant and permanent | For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the permanent is given by
... | #R | R | library(combinat)
perm <- function(A)
{
stopifnot(is.matrix(A))
n <- nrow(A)
if(n != ncol(A)) stop("Matrix is not square.")
if(n < 1) stop("Matrix has a dimension of size 0.")
sum(sapply(combinat::permn(n), function(sigma) prod(sapply(1:n, function(i) A[i, sigma[i]]))))
}
#We copy our test cases from the Py... | Give a code snippet in #R
For a given matrix, return the determinant and the permanent of the matrix.
The determinant is given by
det
(
A
)
=
∑
σ
sgn
(
σ
)
∏
i
=
1
n
M
i
,
σ
i
{\displaystyle \det(A)=\sum _{\sigma }\operatorname {sgn}(\sigma )\prod _{i=1}^{n}M_{i,\sigma _{i}}}
while the p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player) | Guess the number/With feedback (player) | Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score... | #Elixir | Elixir | defmodule Game do
def guess(a..b) do
x = Enum.random(a..b)
guess(x, a..b, div(a+b, 2))
end
defp guess(x, a.._b, guess) when x < guess do
IO.puts "Is it #{guess}? Too High."
guess(x, a..guess-1, div(a+guess, 2))
end
defp guess(x, _a..b, guess) when x > guess do
IO.puts "Is it #{guess}? To... | Give a code snippet in #Elixir
Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mean_angle | Averages/Mean angle | When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first reading was of 350 degrees and the ... | #Kotlin | Kotlin | // version 1.0.5-2
fun meanAngle(angles: DoubleArray): Double {
val sinSum = angles.sumByDouble { Math.sin(it * Math.PI / 180.0) }
val cosSum = angles.sumByDouble { Math.cos(it * Math.PI / 180.0) }
return Math.atan2(sinSum / angles.size, cosSum / angles.size) * 180.0 / Math.PI
}
fun main(args: Array<S... | Give a code snippet in #Kotlin
When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first rea... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ascending_primes | Ascending primes | Generate and show all primes with strictly ascending decimal digits.
Aside: Try solving without peeking at existing solutions. I had a weird idea for generating
a prime sieve faster, which needless to say didn't pan out. The solution may be p(r)etty trivial
but generating them quickly is at least mildly interesting.
T... | #Go | Go | package main
import (
"fmt"
"rcu"
"sort"
)
var ascPrimesSet = make(map[int]bool) // avoids duplicates
func generate(first, cand, digits int) {
if digits == 0 {
if rcu.IsPrime(cand) {
ascPrimesSet[cand] = true
}
return
}
for i := first; i < 10; i++ {
... | Give a code snippet in #Go
Generate and show all primes with strictly ascending decimal digits.
Aside: Try solving without peeking at existing solutions. I had a weird idea for generating
a prime sieve faster, which needless to say didn't pan out. The solution may be p(r)etty trivial
but generating them quickly is at... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Attractive_numbers | Attractive numbers | A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
Show sequence items up to 120.... | #BCPL | BCPL | get "libhdr"
manifest $( MAXIMUM = 120 $)
let sieve(prime, max) be
$( for i=0 to max do i!prime := i>=2
for i=2 to max>>1 if i!prime
$( let j = i<<1
while j <= max do
$( j!prime := false
j := j+i
$)
$)
$)
let factors(n, prime, max) = valof
$( let count = 0
fo... | Give a code snippet in #BCPL
A number is an attractive number if the number of its prime factors (whether distinct or not) is also prime.
Example
The number 20, whose prime decomposition is 2 × 2 × 5, is an attractive number because the number of its prime factors (3) is also prime.
Task
Sh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mayan_calendar | Mayan calendar | The ancient Maya people had two somewhat distinct calendar systems.
In somewhat simplified terms, one is a cyclical calendar known as The Calendar Round,
that meshes several sacred and civil cycles; the other is an offset calendar
known as The Long Count, similar in many ways to the Gregorian calendar.
The Calendar R... | #Go | Go | package main
import (
"fmt"
"strconv"
"strings"
"time"
)
var sacred = strings.Fields("Imix’ Ik’ Ak’bal K’an Chikchan Kimi Manik’ Lamat Muluk Ok Chuwen Eb Ben Hix Men K’ib’ Kaban Etz’nab’ Kawak Ajaw")
var civil = strings.Fields("Pop Wo’ Sip Sotz’ Sek Xul Yaxk’in Mol Ch’en Yax Sak’ Keh Mak K’ank’in ... | Give a code snippet in #Go
The ancient Maya people had two somewhat distinct calendar systems.
In somewhat simplified terms, one is a cyclical calendar known as The Calendar Round,
that meshes several sacred and civil cycles; the other is an offset calendar
known as The Long Count, similar in many ways to the Gregori... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #Octave | Octave |
in = fopen("input.txt", "r", "native");
out = fopen("output.txt", "w","native");
if (in == -1)
disp("Error opening input.txt for reading.");
else
if (out == -1)
disp("Error opening output.txt for writing.");
else
while (1)
[val,count]=fread(in,1,"uchar",0,"native");
if (count > 0)
count=fwrite(out,val,"uc... | Give a code snippet in #Octave
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/N%27th | N'th | Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show here the output for at least t... | #Yabasic | Yabasic |
sub ordinal$ (n)
NMod10 = mod(n, 10)
NMod100 = mod(n, 100)
if (NMod10 = 1) and (NMod100 <> 11) then
return "st"
else
if (NMod10 = 2) and (NMod100 <> 12) then
return "nd"
else
if (NMod10 = 3) and (NMod100 <> 13) then
return "rd"
else
... | Give a code snippet in #Yabasic
Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to sh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parse_an_IP_Address | Parse an IP Address | The purpose of this task is to demonstrate parsing of text-format IP addresses, using IPv4 and IPv6.
Taking the following as inputs:
127.0.0.1
The "localhost" IPv4 address
127.0.0.1:80
The "localhost" IPv4 address, with a specified port (80)
::1
The "localhost" IPv6 address
[::1]:80
The "localhost" IPv6... | #Julia | Julia |
const testdata = ["127.0.0.1", "127.0.0.1:80", "::1", "[::1]:80",
"2605:2700:0:3::4713:93e3", "[2605:2700:0:3::4713:93e3]:80",
"::ffff:192.168.173.22", "[::ffff:192.168.173.22]:80",
"1::", "[1::]:80", "::", "[::]:80"]
maybev4(ip) = search(ip, '.') > 0 && length(... | Give a code snippet in #Julia
The purpose of this task is to demonstrate parsing of text-format IP addresses, using IPv4 and IPv6.
Taking the following as inputs:
127.0.0.1
The "localhost" IPv4 address
127.0.0.1:80
The "localhost" IPv4 address, with a specified port (80)
::1
The "localhost" IPv6 address
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Benford%27s_law | Benford's law |
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the first-digit law, refers to the freque... | #Raku | Raku | sub benford(@a) { bag +« @a».substr(0,1) }
sub show(%distribution) {
printf "%9s %9s %s\n", <Actual Expected Deviation>;
for 1 .. 9 -> $digit {
my $actual = %distribution{$digit} * 100 / [+] %distribution.values;
my $expected = (1 + 1 / $digit).log(10) * 100;
printf "%d: %5.2f%% | %5.... | Give a code snippet in #Raku
This page uses content from Wikipedia. The original article was at Benford's_law. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Benford's law, also called the first-d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Character_codes | Character codes |
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
Conversely, given a code, print out... | #ALGOL_68 | ALGOL 68 | main:(
printf(($gl$, ABS "a")); # for ASCII this prints "+97" EBCDIC prints "+129" #
printf(($gl$, REPR 97)) # for ASCII this prints "a"; EBCDIC prints "/" #
) | Give a code snippet in #ALGOL_68
Task
Given a character value in your language, print its code (could be ASCII code, Unicode code, or whatever your language uses).
Example
The character 'a' (lowercase letter A) has a code of 97 in ASCII (as well as Unicode, as ASCII forms the beginning of Unicode).
C... | 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
| #Maple | Maple | printf("String:"); string_value := readline();
printf("Integer: "); int_value := parse(readline()); | Give a code snippet in #Maple
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/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #Befunge | Befunge | v_$0:8p>:#v_:18p08g1-08p >:08g`!v
~->p5p ^ 0v1p80-1g80vj!-g5g80g5_0'ev
:a^80+1:g8<>8g1+:18pv>0"eslaF">:#,_@
[[relet]]-2010------>003-x -^"Tru"< | Give a code snippet in #Befunge
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort | Sorting algorithms/Cocktail 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
... | #Icon_and_Unicon | Icon and Unicon | procedure main() #: demonstrate various ways to sort a list and string
demosort(cocktailsort,[3, 14, 1, 5, 9, 2, 6, 3],"qwerty")
end
procedure cocktailsort(X,op) #: return sorted list
local i,swapped
op := sortop(op,X) # select how and what we sort
swapped :... | Give a code snippet in #Icon_and_Unicon
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list_of_records | Search a list of records | Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task[edit]
Write a function/method/et... | #Wren | Wren | import "/dynamic" for Tuple
var Element = Tuple.create("Element", ["record", "index"])
var findFirst = Fn.new { |seq, pred|
var i = 0
for (e in seq) {
if (pred.call(e)) return Element.new(e, i)
i = i + 1
}
return Element.new(null, -1)
}
var City = Tuple.create("City", ["name", "pop... | Give a code snippet in #Wren
Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task[ed... | 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
... | #uBasic.2F4tH | uBasic/4tH | PRINT "Bubble sort:"
n = FUNC (_InitArray)
PROC _ShowArray (n)
PROC _Bubblesort (n)
PROC _ShowArray (n)
PRINT
END
_Bubblesort PARAM(1) ' Bubble sort
LOCAL (2)
DO
b@ = 0
FOR c@ = 1 TO a@-1
IF @(c@-1) > @(c@) THEN PROC _Swap (c@, c@-1) : b@ = c@
NEXT
a@ = b@
U... | Give a code snippet in #uBasic.2F4tH
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/Strip_block_comments | Strip block comments | A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos should at least handle simple, non-ne... | #Prolog | Prolog |
:- system:set_prolog_flag(double_quotes,codes) .
strip_block_comments(INPUTz)
:-
strip_block_comments(INPUTz,OUTPUTz) ,
system:format("```~n",[OUTPUTz]) ,
system:format("~s~n",[OUTPUTz]) ,
system:format("```~n",[OUTPUTz])
.
strip_block_comments(INPUTz,OUTPUTz)
:-
prolog:phrase(block(OUTPUTz),INPUTz)
.
block([... | Give a code snippet in #Prolog
A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos shoul... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #Haskell | Haskell | import Data.Map
makeMap ks vs = fromList $ zip ks vs
mymap = makeMap ['a','b','c'] [1,2,3] | Give a code snippet in #Haskell
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Super-d_numbers | Super-d numbers | A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or super-d.
Task
Write a... | #R | R | library(Rmpfr)
options(scipen = 999)
find_super_d_number <- function(d, N = 10){
super_number <- c(NA)
n = 0
n_found = 0
while(length(super_number) < N){
n = n + 1
test = d * mpfr(n, precBits = 200) ** d #Here I augment precision
test_formatted = .mpfr2str(test)$str #and I extract the... | Give a code snippet in #R
A super-d number is a positive, decimal (base ten) integer n such that d × nd has at least d consecutive digits d where
2 ≤ d ≤ 9
For instance, 753 is a super-3 number because 3 × 7533 = 1280873331.
Super-d numbers are also shown on MathWorld™ as super-d or ... | christopher/rosetta-code | |
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([], [... | Give a code snippet in #Prolog
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 rang... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_sphere | Draw a sphere | Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a Deathstar
| #SVG | SVG |
class Sphere: UIView{
override func drawRect(rect: CGRect)
{
let context = UIGraphicsGetCurrentContext()
let locations: [CGFloat] = [0.0, 1.0]
let colors = [UIColor.whiteColor().CGColor,
UIColor.blueColor().CGColor]
let colorspace = CGColorSpaceCreateDeviceRGB()
let gradient = CG... | Give a code snippet in #SVG
Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a Deat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations | Combinations | Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0 2 4
0 3 4
1 2 3
1 2 4
1 3 4
2 3 4
... | #CLU | CLU | % generate the size-M combinations from 0 to n-1
combinations = iter (m, n: int) yields (sequence[int])
if m<=n then
state: array[int] := array[int]$predict(1, m)
for i: int in int$from_to(0, m-1) do
array[int]$addh(state, i)
end
i: int := m
while i>0 do
... | Give a code snippet in #CLU
Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0 2 4
0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers/Pascal%27s_triangle | Catalan numbers/Pascal's triangle | Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that generates Catalan Numbers using onl... | #Elixir | Elixir | defmodule Catalan do
def numbers(num) do
{result,_} = Enum.reduce(1..num, {[],{0,1}}, fn i,{list,t0} ->
t1 = numbers(i, t0)
t2 = numbers(i+1, Tuple.insert_at(t1, i+1, elem(t1, i)))
{[elem(t2, i+1) - elem(t2, i) | list], t2}
end)
Enum.reverse(result)
end
defp numbers(0, t), do: t
... | Give a code snippet in #Elixir
Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that gen... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For | Loops/For | “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers.
... | #OCaml | OCaml | for i = 1 to 5 do
for j = 1 to i do
print_string "*"
done;
print_newline ()
done | Give a code snippet in #OCaml
“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_squares_of_doubly_even_order | Magic squares of doubly even order | A magic square is an N×N square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant).
A magic square of doubly even order has a size that is a multiple of four (e... | #ALGOL_68 | ALGOL 68 | BEGIN # Magic squares of doubly even order #
PROC doubly even magic square = ( INT n )[,]INT:
IF n MOD 4 /= 0 THEN
# not a doubly even number #
[ 1 : 0, 1 : 0 ]INT empty square;
empty square
ELSE
# ok to create the square #
[ 1 : 4, 1 : 4... | Give a code snippet in #ALGOL_68
A magic square is an N×N square matrix whose numbers consist of consecutive numbers arranged so that the sum of each row and column, and both diagonals are equal to the same sum (which is called the magic number or magic constant).
A magic square of doubly even order has a si... | christopher/rosetta-code | |
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
| #R | R | # For reproducibility, set the seed:
set.seed(12345L)
result <- rnorm(1000, mean = 1, sd = 0.5) | Give a code snippet in #R
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 tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #FreeBASIC | FreeBASIC | ' version 20-06-2015
' compile with: fbc -s console "filename".bas
#Ifndef TRUE ' define true and false for older freebasic versions
#Define FALSE 0
#Define TRUE Not FALSE
#EndIf
Function reverse(norm As String) As Integer
Dim As String rev
Dim As Integer i, l = Len(norm) -1
rev = nor... | Give a code snippet in #FreeBASIC
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #LOLCODE | LOLCODE | HAI 1.3
VISIBLE "SEED ME, FEMUR! "!
I HAS A seed, GIMMEH seed
HOW IZ I randomizin
seed R MOD OF SUM OF 1 AN PRODUKT OF 69069 AN seed AN 10
IF U SAY SO
I IZ randomizin MKAY
I HAS A answer ITZ SUM OF seed AN 1
I HAS A guess
IM IN YR guesser
VISIBLE "WUTS MY NUMBR? "!
GIMMEH guess, guess IS NOW A NUMBR... | Give a code snippet in #LOLCODE
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #Gleam | Gleam | import gleam/int
import gleam/io
import gleam/iterator
pub fn main() {
iterator.range(1, 101)
|> iterator.map(to_fizzbuzz)
|> iterator.map(io.println)
|> iterator.run
}
fn to_fizzbuzz(n: Int) -> String {
case n % 3, n % 5 {
0, 0 -> "FizzBuzz"
0, _ -> "Fizz"
_, 0 -> "Buzz"
_, _ -> int.to_st... | Give a code snippet in #Gleam
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-1 | SHA-1 | SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to identify commits.
A US government... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/sha.h>
int main()
{
int i;
unsigned char result[SHA_DIGEST_LENGTH];
const char *string = "Rosetta Code";
SHA1(string, strlen(string), result);
for(i = 0; i < SHA_DIGEST_LENGTH; i++)
printf("%02x%c", result[i], i < (SHA_DIGE... | Give a code snippet in #C
SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to identif... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm | Bitmap/Midpoint circle algorithm | Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| #Tcl | Tcl | package require Tcl 8.5
package require Tk
proc drawCircle {image colour point radius} {
lassign $point x0 y0
setPixel $image $colour [list $x0 [expr {$y0 + $radius}]]
setPixel $image $colour [list $x0 [expr {$y0 - $radius}]]
setPixel $image $colour [list [expr {$x0 + $radius}] $y0]
setPixel $im... | Give a code snippet in #Tcl
Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| 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... | #VBScript | VBScript | Function Luhn_Test(cc)
cc = RevString(cc)
s1 = 0
s2 = 0
For i = 1 To Len(cc)
If i Mod 2 > 0 Then
s1 = s1 + CInt(Mid(cc,i,1))
Else
tmp = CInt(Mid(cc,i,1))*2
If tmp < 10 Then
s2 = s2 + tmp
Else
s2 = s2 + CInt(Right(CStr(tmp),1)) + 1
End If
End If
Next
If Right(CStr(s1 + s2),1) = "0" T... | Give a code snippet in #VBScript
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Teacup_rim_text | Teacup rim text | On a set of coasters we have, there's a picture of a teacup. On the rim of the teacup the word TEA appears a number of times separated by bullet characters (•).
It occurred to me that if the bullet were removed and the words run together, you could start at any letter and still end up with a meaningful three... | #Java | Java | import java.io.*;
import java.util.*;
public class Teacup {
public static void main(String[] args) {
if (args.length != 1) {
System.err.println("usage: java Teacup dictionary");
System.exit(1);
}
try {
findTeacupWords(loadDictionary(args[0]));
} ... | Give a code snippet in #Java
On a set of coasters we have, there's a picture of a teacup. On the rim of the teacup the word TEA appears a number of times separated by bullet characters (•).
It occurred to me that if the bullet were removed and the words run together, you could start at any letter and still ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fivenum | Fivenum | Many big data or scientific programs use boxplots to show distributions of data. In addition, sometimes saving large arrays for boxplots can be impractical and use extreme amounts of RAM. It can be useful to save large arrays as arrays with five numbers to save memory.
For example, the R programming language i... | #Raku | Raku | sub fourths ( Int $end ) {
my $end_22 = $end div 2 / 2;
return 0, $end_22, $end/2, $end - $end_22, $end;
}
sub fivenum ( @nums ) {
my @x = @nums.sort(+*)
or die 'Input must have at least one element';
my @d = fourths(@x.end);
return ( @x[@d».floor] Z+ @x[@d».ceiling] ) »/» 2;
}
say .... | Give a code snippet in #Raku
Many big data or scientific programs use boxplots to show distributions of data. In addition, sometimes saving large arrays for boxplots can be impractical and use extreme amounts of RAM. It can be useful to save large arrays as arrays with five numbers to save memory.
For example, th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_in_octal | Count in octal | Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.
Related task
Integer sequ... | #NewLISP | NewLISP | ; file: ocount.lsp
; url: http://rosettacode.org/wiki/Count_in_octal
; author: oofoe 2012-01-29
; Although NewLISP itself uses a 64-bit integer representation, the
; format function relies on underlying C library's printf function,
; which can only handle a 32-bit octal number on this implementation.
(for (i 0... | Give a code snippet in #NewLISP
Task
Produce a sequential count in octal, starting at zero, and using an increment of a one for each consecutive number.
Each number should appear on a single line, and the program should count until terminated, or until the maximum value of the numeric type in use is reached.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Power_set | Power set | A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a set S, the power set (or pow... | #TXR | TXR | (defun power-set (s)
(mappend* (op comb s) (range 0 (length s)))) | Give a code snippet in #TXR
A set is a collection (container) of certain values,
without any particular order, and no repeated values.
It corresponds with a finite set in mathematics.
A set can be implemented as an associative array (partial mapping)
in which the value of each key-value pair is ignored.
Given a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parametric_polymorphism | Parametric polymorphism | Parametric Polymorphism
type variables
Task
Write a small example for a type declaration that is parametric over another type, together with a short bit of code (and its type signature) that uses it.
A good example is a container type, let's say a binary tree, together with some function that traverses the tree, ... | #J | J | public class Tree<T>{
private T value;
private Tree<T> left;
private Tree<T> right;
public void replaceAll(T value){
this.value = value;
if (left != null)
left.replaceAll(value);
if (right != null)
right.replaceAll(value);
}
} | Give a code snippet in #J
Parametric Polymorphism
type variables
Task
Write a small example for a type declaration that is parametric over another type, together with a short bit of code (and its type signature) that uses it.
A good example is a container type, let's say a binary tree, together with some functio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Move-to-front_algorithm | Move-to-front algorithm | Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is useful in some compression algorithms... | #Factor | Factor | USING: formatting kernel locals make sequences ;
: to-front ( elt seq -- seq' ) over [ remove ] dip prefix ;
: encode ( symbols msg -- indices )
[ [ swap 2dup index , to-front ] each ] { } make nip ;
: decode ( symbols indices -- msg )
[ [ swap [ nth ] keep over , to-front ] each ] "" make nip ;
:: roun... | Give a code snippet in #Factor
Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is usefu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Haskell | Haskell | import Text.Regex
str = "I am a string"
case matchRegex (mkRegex ".*string$") str of
Just _ -> putStrLn $ "ends with 'string'"
Nothing -> return () | Give a code snippet in #Haskell
Task
match a string against a regular expression
substitute part of a string using a regular expression
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Nested | Loops/Nested | Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is met.
Specifically, this task als... | #Frink | Frink | array = new array[[10,10], {|x,y| random[1,20]}]
println["array is:\n" + formatTable[array, "right"] + "\n"]
[rows,cols] = array.dimensions[]
ROW:
for r = 0 to rows-1
for c = 0 to cols-1
{
print[array@r@c + " " ]
if array@r@c == 20
break ROW
} | Give a code snippet in #Frink
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is me... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Merge_and_aggregate_datasets | Merge and aggregate datasets | Merge and aggregate datasets
Task
Merge and aggregate two datasets as provided in .csv files into a new resulting dataset.
Use the appropriate methods and data structures depending on the programming language.
Use the most common libraries only when built-in functionality is not sufficient.
Note
Either lo... | #R | R | # load data from csv files
# setwd("C:\Temp\csv\")
# df_patient <- read.csv(file="patients.csv", header = TRUE, sep = ",")
# df_visits <- read.csv(file="visits.csv", header = TRUE, sep = ",", dec = ".", colClasses=c("character","character","numeric"))
# load data hard coded, create data frames
df_patient <- read.tabl... | Give a code snippet in #R
Merge and aggregate datasets
Task
Merge and aggregate two datasets as provided in .csv files into a new resulting dataset.
Use the appropriate methods and data structures depending on the programming language.
Use the most common libraries only when built-in functionality is not suf... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mertens_function | Mertens function | The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number.
It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möbius numbers from n == 1 through n... | #ALGOL_W | ALGOL W | begin % compute values of the Mertens function %
integer array M ( 1 :: 1000 );
integer k, zero, cross;
% Generate Mertens numbers %
M( 1 ) := 1;
for n := 2 until 1000 do begin
M( n ) := 1;
for k := 2 until n do M( n ) ... | Give a code snippet in #ALGOL_W
The Mertens function M(x) is the count of square-free integers up to x that have an even number of prime factors, minus the count of those that have an odd number.
It is an extension of the Möbius function. Given the Möbius function μ(n), the Mertens function M(x) is the sum of the Möb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Price_fraction | Price fraction | A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 and 1.00, rescale according to ... | #AppleScript | AppleScript | -- This handler just returns the standardised real value. It's up to external processes to format it for display.
on standardisePrice(input)
set integerPart to input div 1.0
set fractionalPart to input mod 1.0
if (fractionalPart is 0.0) then
return input as real
else if (fractionalPart < 0.0... | Give a code snippet in #AppleScript
A friend of mine runs a pharmacy. He has a specialized function in his Dispensary application which receives a decimal value of currency and replaces it to a standard value. This value is regulated by a government department.
Task
Given a floating point value between 0.00 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pragmatic_directives | Pragmatic directives | Pragmatic directives cause the language to operate in a specific manner, allowing support for operational variances within the program code (possibly by the loading of specific or alternative modules).
Task
List any pragmatic directives supported by the language, and demonstrate how to activate and deactivate... | #J | J | 9!:1 random seed (incomplete specification of state -- see 9!:45)
9!:3 default display for non-nouns
9!:7 box drawing characters
9!:9 error messages
9!:11 print precision
9!:17 centering (or not) when box contents are smaller than boxes
9!:19 comparison tolerance
9!:21 memory limit
9!:25 security level
9!:27 text of i... | Give a code snippet in #J
Pragmatic directives cause the language to operate in a specific manner, allowing support for operational variances within the program code (possibly by the loading of specific or alternative modules).
Task
List any pragmatic directives supported by the language, and demonstrate how... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-transitive_dice | Non-transitive dice | Let our dice select numbers on their faces with equal probability, i.e. fair dice.
Dice may have more or less than six faces. (The possibility of there being a
3D physical shape that has that many "faces" that allow them to be fair dice,
is ignored for this task - a die with 3 or 33 defined sides is defined by the
numb... | #MiniZinc | MiniZinc |
%Non transitive dice. Nigel Galloway, September 14th., 2020
int: die; int: faces; set of int: values;
predicate pN(array[1..faces] of var values: n, array[1..faces] of var values: g) = sum(i in 1..faces,j in 1..faces)(if n[i]<g[j] then 1 elseif n[i]>g[j] then -1 else 0 endif)>0;
predicate pG(array[1..faces] of var va... | Give a code snippet in #MiniZinc
Let our dice select numbers on their faces with equal probability, i.e. fair dice.
Dice may have more or less than six faces. (The possibility of there being a
3D physical shape that has that many "faces" that allow them to be fair dice,
is ignored for this task - a die with 3 or 33 de... | 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
| #Wren | Wren | System.print("Hello world!") | Give a code snippet in #Wren
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/Strip_a_set_of_characters_from_a_string | Strip a set of characters from a string | Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any characters in the second argument:
print str... | #360_Assembly | 360 Assembly | * Strip a set of characters from a string 07/07/2016
STRIPCH CSECT
USING STRIPCH,R13 base register
B 72(R15) skip savearea
DC 17F'0' savearea
STM R14,R12,12(R13) prolog
ST R13,4(R15) " <-
ST R15,... | Give a code snippet in #360_Assembly
Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any characte... | christopher/rosetta-code | |
http://rosettacode.org/wiki/JortSort | JortSort |
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
... | #Delphi | Delphi |
program JortSort;
{$APPTYPE CONSOLE}
{$R *.res}
uses
System.SysUtils,
System.Generics.Collections,
System.Generics.Defaults;
type
TArrayHelper = class helper for TArray
public
class function JortSort<T>(const original: TArray<T>): Boolean; static;
end;
{ TArrayHelper }
class function TArrayH... | Give a code snippet in #Delphi
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 s... | 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... | #8086_Assembly | 8086 Assembly | cpu 8086
bits 16
org 100h
section .text
jmp demo
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;; Subroutine "blocks": see if the $-terminated string in DS:BX
;;; can be written with the blocks.
;;; Returns: carry flag set if word is accepted.
;;; Uses registers: AL, BX, CX, SI, DI
... | Give a code snippet in #8086_Assembly
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... | 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... | #Racket | Racket | #lang racket
;;; Generate the headings and boxes
(define (i->heading/box i)
(values (let ((heading (* i #e11.25)))
(case (modulo i 3)
((1) (+ heading #e5.62))
((2) (- heading #e5.62))
(else heading)))
(add1 (modulo i 32))))
(define-values (headings-list box-list... | Give a code snippet in #Racket
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 d... | 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... | #Pascal | Pascal | # These variables are all different
$dog='Benjamin';
$Dog='Samba';
$DOG='Bernie';
print "The three dogs are named $dog, $Dog, and $DOG \n" | Give a code snippet in #Pascal
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/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
... | #jq | jq | # As soon as "condition" is true, then emit . and stop:
def do_until(condition; next):
def u: if condition then . else (next|u) end;
u;
# input: an array
def gnomeSort:
def swap(i;j): .[i] as $x | .[i]=.[j] | .[j]=$x;
length as $length
# state: [i, j, ary]
| [1, 2, .]
| do_until( .[0] >= $length;
... | Give a code snippet in #jq
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Positional_read | Terminal control/Positional read | Determine the character displayed on the screen at column 3, row 6 and store that character in a variable. Note that it is permissible to utilize system or language provided methods or system provided facilities, system maintained records or available buffers or system maintained display records to achieve this task, r... | #Phix | Phix | --
-- demo\rosetta\Positional_read.exw
-- ================================
--
without js -- (position, get_screen_char)
position(6,1) -- line 6 column 1 (1-based)
puts(1,"abcdef")
integer {ch,attr} = get_screen_char(6,3)
printf(1,"\n\n=>%c",ch)
{} = wait_key()
| Give a code snippet in #Phix
Determine the character displayed on the screen at column 3, row 6 and store that character in a variable. Note that it is permissible to utilize system or language provided methods or system provided facilities, system maintained records or available buffers or system maintained display r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Archimedean_spiral | Archimedean spiral |
The Archimedean spiral is a spiral named after the Greek mathematician Archimedes.
An Archimedean spiral can be described by the equation:
r
=
a
+
b
θ
{\displaystyle \,r=a+b\theta }
with real numbers a and b.
Task
Draw an Archimedean spiral.
| #Kotlin | Kotlin | // version 1.1.0
import java.awt.*
import javax.swing.*
class ArchimedeanSpiral : JPanel() {
init {
preferredSize = Dimension(640, 640)
background = Color.white
}
private fun drawGrid(g: Graphics2D) {
g.color = Color(0xEEEEEE)
g.stroke = BasicStroke(2f)
val angl... | Give a code snippet in #Kotlin
The Archimedean spiral is a spiral named after the Greek mathematician Archimedes.
An Archimedean spiral can be described by the equation:
r
=
a
+
b
θ
{\displaystyle \,r=a+b\theta }
with real numbers a and b.
Task
Draw an Archimedean spiral.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Anonymous_recursion | Anonymous recursion | While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), causing unwanted side-effects, and/or the f... | #M2000_Interpreter | M2000 Interpreter |
A$={{ Module "Fibonacci" : Read X :If X<0 then {Error {X<0}} Else Fib=Lambda (x)->if(x>1->fib(x-1)+fib(x-2), x) : =fib(x)}}
Try Ok {
Print Function(A$, -12)
}
If Error or Not Ok Then Print Error$
Print Function(A$, 12)=144 ' true
| Give a code snippet in #M2000_Interpreter
While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), ca... | christopher/rosetta-code | |
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 ... | #Swift | Swift | ({print($0+$0.debugDescription+")")})("({print($0+$0.debugDescription+\")\")})(") | Give a code snippet in #Swift
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
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Component_Pascal | Component Pascal |
MODULE Arithmetic;
IMPORT CPmain,Console,RTS;
VAR
x,y : INTEGER;
arg : ARRAY 128 OF CHAR;
status : BOOLEAN;
PROCEDURE Error(IN str : ARRAY OF CHAR);
BEGIN
Console.WriteString(str);Console.WriteLn;
HALT(1)
END Error;
BEGIN
IF CPmain.ArgNumber() < 2 THEN Error("Give me two integers!") EN... | Give a code snippet in #Component_Pascal
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Curzon_numbers | Curzon numbers | A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1.
Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1.
Base here does not imply the radix of the counting sys... | #Pascal | Pascal |
program CurzonNumbers;
uses SysUtils;
const
MAX_CURZON_MEG = 100;
RC_LINE_LENGTH = 66;
procedure ListCurzonNumbers( base : integer);
var
k, n, m, x, testBit, maxCurzon : uint64;
nrHits : integer;
lineOut : string;
begin
maxCurzon := 1000000*MAX_CURZON_MEG;
k := uint64( base);
nrHits := 0;
n := 0;
... | Give a code snippet in #Pascal
A Curzon number is defined to be a positive integer n for which 2n + 1 is evenly divisible by 2 × n + 1.
Generalized Curzon numbers are those where the positive integer n, using a base integer k, satisfy the condition that kn + 1 is evenly divisible by k × n + 1.
Base here does not imp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newline_omission | Hello world/Newline omission | Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Standard error
Hello world/Text
| #Blade | Blade | print('Goodbye, World!') | Give a code snippet in #Blade
Some languages automatically insert a newline after outputting a string, unless measures are taken to prevent its output.
Task
Display the string Goodbye, World! without a trailing newline.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Stand... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Formatted_numeric_output | Formatted numeric output | Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| #Visual_Basic | Visual Basic |
Debug.Print Format$(7.125, "00000.000")
| Give a code snippet in #Visual_Basic
Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Variable_declaration_reset | Variable declaration reset | A decidely non-challenging task to highlight a potential difference between programming languages.
Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}. The (non-blank) results may ... | #AWK | AWK |
# syntax: GAWK -f VARIABLE_DECLARATION_RESET.AWK
BEGIN {
n = split("1,2,2,3,4,4,5",arr,",")
for (i=1; i<=n; i++) {
curr = arr[i]
if (i > 1 && prev == curr) {
printf("%s\n",i)
}
prev = curr
}
exit(0)
}
| Give a code snippet in #AWK
A decidely non-challenging task to highlight a potential difference between programming languages.
Using a straightforward longhand loop as in the JavaScript and Phix examples below, show the locations of elements which are identical to the immediately preceding element in {1,2,2,3,4,4,5}.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiple_distinct_objects | Multiple distinct objects | Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they are considered unequal; etc. The code need ... | #Phix | Phix | with javascript_semantics
sequence s = repeat("x",6) ?s
s[$] = 5 ?s
s[1] &= 'y' ?s
-- s[2] = s ?s
s[2] = deep_copy(s) ?s
| Give a code snippet in #Phix
Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they are considere... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #C | C | /*
* File extension is in extensions list (dots allowed).
*
* This problem is trivial because the so-called extension is simply the end
* part of the name.
*/
#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <locale.h>
#include <string.h>
#ifdef _Bool
#includ... | Give a code snippet in #C
File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Spiral_matrix | Spiral matrix | Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 17 18 5
14 23 24 19 6
13 22 21 ... | #C.2B.2B | C++ | #include <vector>
#include <memory> // for auto_ptr
#include <cmath> // for the ceil and log10 and floor functions
#include <iostream>
#include <iomanip> // for the setw function
using namespace std;
typedef vector< int > IntRow;
typedef vector< IntRow > IntTable;
auto_ptr< IntTable > getSpiralArray( int dimensio... | Give a code snippet in #C.2B.2B
Task
Produce a spiral array.
A spiral array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you go around the edges of the array spiraling inwards.
For example, given 5, produce this array:
0 1 2 3 4
15 16 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brazilian_numbers | Brazilian numbers | Brazilian numbers are so called as they were first formally presented at the 1994 math Olympiad Olimpiada Iberoamericana de Matematica in Fortaleza, Brazil.
Brazilian numbers are defined as:
The set of positive integer numbers where each number N has at least one natural number B where 1 < B < N-1 where the represent... | #Raku | Raku | multi is-Brazilian (Int $n where $n %% 2 && $n > 6) { True }
multi is-Brazilian (Int $n) {
LOOP: loop (my int $base = 2; $base < $n - 1; ++$base) {
my $digit;
for $n.polymod( $base xx * ) {
$digit //= $_;
next LOOP if $digit != $_;
}
return True
}
Fa... | Give a code snippet in #Raku
Brazilian numbers are so called as they were first formally presented at the 1994 math Olympiad Olimpiada Iberoamericana de Matematica in Fortaleza, Brazil.
Brazilian numbers are defined as:
The set of positive integer numbers where each number N has at least one natural number B where 1... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_shuffle | Perfect shuffle | A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ K♠→7♠ 8♠ 9♠
J♠ Q♠ K♠→7♠ J♠ 8♠ Q♠ 9♠ K♠
When you ... | #Python | Python |
import doctest
import random
def flatten(lst):
"""
>>> flatten([[3,2],[1,2]])
[3, 2, 1, 2]
"""
return [i for sublst in lst for i in sublst]
def magic_shuffle(deck):
"""
>>> magic_shuffle([1,2,3,4])
[1, 3, 2, 4]
"""
half = len(deck) // 2
return flatten(zip(deck[:half]... | Give a code snippet in #Python
A perfect shuffle (or faro/weave shuffle) means splitting a deck of cards into equal halves, and perfectly interleaving them - so that you end up with the first card from the left half, followed by the first card from the right half, and so on:
7♠ 8♠ 9♠ J♠ Q♠ K♠→7♠ 8♠ 9♠
J♠ Q♠ ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Towers_of_Hanoi | Towers of Hanoi | Task
Solve the Towers of Hanoi problem with recursion.
| #Quackery | Quackery | [ stack ] is rings ( --> [ )
[ rings share
depth share -
8 * times sp
emit sp emit sp
say 'move' cr ] is echomove ( c c --> )
[ dup rings put
depth put
char a char b char c
[ swap decurse
rot 2dup echomove
decurse
swap rot ... | Give a code snippet in #Quackery
Task
Solve the Towers of Hanoi problem with recursion.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Angle_difference_between_two_bearings | Angle difference between two bearings | Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range -180 to +180 degrees.
... | #Ruby | Ruby | def getDifference(b1, b2)
r = (b2 - b1) % 360.0
# Ruby modulus has same sign as divisor, which is positive here,
# so no need to consider negative case
if r >= 180.0
r -= 360.0
end
return r
end
if __FILE__ == $PROGRAM_NAME
puts "Input in -180 to +180 range"
puts getDifference(20.0, 45.0)
puts getDifference... | Give a code snippet in #Ruby
Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range -... | 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.
| #UNIX_Shell | UNIX Shell |
#!/bin/bash
DELAY=0 # increase this if printing of matrices should be slower
echo "This script takes two matrices, henceforth called A and B,
and returns their product, AB.
For the time being, matrices can have integer components only.
"
read -p "Number of rows of matrix A: " arows
read -p "Number of co... | Give a code snippet in #UNIX_Shell
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/Numerical_integration/Gauss-Legendre_Quadrature | Numerical integration/Gauss-Legendre Quadrature |
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting function
W
(
x
)
{\displaystyle ... | #Raku | Raku | multi legendre-pair( 1 , $x) { $x, 1 }
multi legendre-pair(Int $n, $x) {
my ($m1, $m2) = legendre-pair($n - 1, $x);
my \u = 1 - 1 / $n;
(1 + u) * $x * $m1 - u * $m2, $m1;
}
multi legendre( 0 , $ ) { 1 }
multi legendre(Int $n, $x) { legendre-pair($n, $x)[0] }
multi legendre-prime( 0 , $ ) { 0 }
... | Give a code snippet in #Raku
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting function... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #jq | jq | (1,2,3,4,5,6,7,8,9) | select(. % 2 == 0) | Give a code snippet in #jq
Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-256 | SHA-256 | SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.
Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa542713965b785e5cc2f707d6468d7d1124cdfcf
| #Smalltalk | Smalltalk |
(SHA256 new hashStream: 'Rosetta code' readStream) hex.
| Give a code snippet in #Smalltalk
SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.
Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa54271396... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_name | Program name | The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal A... | #Ada | Ada | with Ada.Command_Line, Ada.Text_IO;
procedure Command_Name is
begin
Ada.Text_IO.Put_Line(Ada.Command_Line.Command_Name);
end Command_Name; | Give a code snippet in #Ada
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script na... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Gambas | Gambas | Public Sub Main()
Dim sString As String = "THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG"
Print Mid(sString, 11, 5) 'Starting from n characters in and of m length
Print Mid(sString, 17) 'Starting from n characters in, up to the end of the string
Print Left(sString, -1) ... | Give a code snippet in #Gambas
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Primality_by_trial_division | Primality by trial division | Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops are allowed.
Related tasks
... | #OCaml | OCaml | let is_prime n =
if n = 2 then true
else if n < 2 || n mod 2 = 0 then false
else
let rec loop k =
if k * k > n then true
else if n mod k = 0 then false
else loop (k+2)
in loop 3 | Give a code snippet in #OCaml
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops... | 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,... | #LIL | LIL | # (not) Arrays, in LIL
set a [list abc def ghi]
set b [list 4 5 6]
print [index $a 0]
print [index $b 1]
print [count $a]
append b [list 7 8 9]
print [count $b]
print $b | Give a code snippet in #LIL
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 retriev... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_name | Program name | The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal A... | #Common_Lisp | Common Lisp | ;;; Play nice with shebangs
(set-dispatch-macro-character #\# #\!
(lambda (stream character n)
(declare (ignore character n))
(read-line stream nil nil t)
nil)) | Give a code snippet in #Common_Lisp
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Rational | Arithmetic/Rational | Task
Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language.
Example
Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number).
Fur... | #C | C | #include <stdio.h>
#include <stdlib.h>
#define FMT "%lld"
typedef long long int fr_int_t;
typedef struct { fr_int_t num, den; } frac;
fr_int_t gcd(fr_int_t m, fr_int_t n)
{
fr_int_t t;
while (n) { t = n; n = m % n; m = t; }
return m;
}
frac frac_new(fr_int_t num, fr_int_t den)
{
frac a;
if (!den) {
printf("d... | Give a code snippet in #C
Task
Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language.
Example
Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Move-to-front_algorithm | Move-to-front algorithm | Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is useful in some compression algorithms... | #Racket | Racket | #lang racket
(define default-symtab "abcdefghijklmnopqrstuvwxyz")
(define (move-to-front:encode in (symtab default-symtab))
(define inner-encode
(match-lambda**
[((? string? (app string->list in)) st acc) ; make input all listy
(inner-encode in st acc)]
[(in (? string? (app string->list st)) acc... | Give a code snippet in #Racket
Given a symbol table of a zero-indexed array of all possible input symbols
this algorithm reversibly transforms a sequence
of input symbols into an array of output numbers (indices).
The transform in many cases acts to give frequently repeated input symbols
lower indices which is usefu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_a_set_of_characters_from_a_string | Strip a set of characters from a string | Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any characters in the second argument:
print str... | #PL.2FI | PL/I | strip_chars: procedure (text, chars) returns (character (100) varying);
declare text character (*) varying, chars character (*) varying;
declare out_text character (100);
declare ch character (1);
declare (i, j) fixed binary;
j = 0;
do i = 1 to length(text);
ch = substr(text, i, 1);
if i... | Give a code snippet in #PL.2FI
Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any characters in ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Totient_function | Totient function | The totient function is also known as:
Euler's totient function
Euler's phi totient function
phi totient function
Φ function (uppercase Greek phi)
φ function (lowercase Greek phi)
Definitions (as per number theory)
The totient function:
counts the integers up to a given positiv... | #zkl | zkl | fcn totient(n){ [1..n].reduce('wrap(p,k){ p + (n.gcd(k)==1) }) }
fcn isPrime(n){ totient(n)==(n - 1) } | Give a code snippet in #zkl
The totient function is also known as:
Euler's totient function
Euler's phi totient function
phi totient function
Φ function (uppercase Greek phi)
φ function (lowercase Greek phi)
Definitions (as per number theory)
The totient function:
counts the i... | 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... | #M2000_Interpreter | M2000 Interpreter |
Module UseBlink {
Def boolean direction=True
rotating$ =lambda$ a$="Hello World! " (direction as boolean)->{
=a$
a$=if$(direction->right$(a$,1)+mid$(a$,1, len(a$)-1), mid$(a$,2)+left$(a$,1))
}
Declare MyForm Form
Declare MyButton Button Form MyForm
With My... | Give a code snippet in #M2000_Interpreter
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. ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anonymous_recursion | Anonymous recursion | While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), causing unwanted side-effects, and/or the f... | #OCaml | OCaml | let fib n =
let rec real = function
0 -> 1
| 1 -> 1
| n -> real (n-1) + real (n-2)
in
if n < 0 then
None
else
Some (real n) | Give a code snippet in #OCaml
While implementing a recursive function, it often happens that we must resort to a separate helper function to handle the actual recursion.
This is usually the case when directly calling the current function would waste too many resources (stack space, execution time), causing unwant... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Linear_congruential_generator | Linear congruential generator | The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r_{0}}
is a seed.
r
1
... | #Batch | Batch |
@echo off & setlocal enabledelayedexpansion
echo BSD Rand
set /a a=0,cnt=1
:b
set /a "a=1103515245 *a+12345,a&=0x7fffffff, cnt+=1"
call:prettyprint !cnt! !a!
if !cnt! leq 10 goto :b
echo.
echo Microsoft Rand
set /a a=0,cnt=1
:c
set /a "a=214013 *a+2531011,a&=0x7fffffff, b=a>>16,cnt+=1"
call:prettyprint !cnt! !b!
... | Give a code snippet in #Batch
The linear congruential generator is a very simple example of a random number generator.
All linear congruential generators use this formula:
r
n
+
1
=
a
×
r
n
+
c
(
mod
m
)
{\displaystyle r_{n+1}=a\times r_{n}+c{\pmod {m}}}
Where:
r
0
{\displaystyle r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers/Pascal%27s_triangle | Catalan numbers/Pascal's triangle | Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that generates Catalan Numbers using onl... | #Groovy | Groovy |
class Catalan
{
public static void main(String[] args)
{
BigInteger N = 15;
BigInteger k,n,num,den;
BigInteger catalan;
print(1);
for(n=2;n<=N;n++)
{
num = 1;
den = 1;
for(k=2;k<=n;k++)
{
num = num*(n+k);... | Give a code snippet in #Groovy
Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that gen... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Single | Inheritance/Single | This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent types.
Usually inherited properties... | #zkl | zkl | class Animal{}
class Dog(Animal){} class Cat(Animal){}
class Lab(Dog){} class Collie(Dog){}
Collie.linearizeParents | Give a code snippet in #zkl
This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent types.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Benford%27s_law | Benford's law |
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the first-digit law, refers to the freque... | #Ada | Ada | with Ada.Text_IO, Ada.Numerics.Generic_Elementary_Functions;
procedure Benford is
subtype Nonzero_Digit is Natural range 1 .. 9;
function First_Digit(S: String) return Nonzero_Digit is
(if S(S'First) in '1' .. '9'
then Nonzero_Digit'Value(S(S'First .. S'First))
else First_Digit(S(S'F... | Give a code snippet in #Ada
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the first-di... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Null_object | Null object |
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your language by checking to see if an ob... | #Phix | Phix | type nullableString(object o)
return string(o) or o=NULL
end type
nullableString s
s = "hello"
s = NULL
--s = 1 -- error
--s = {1,2,3} -- error
type nullableSequence(object o)
return sequence(o) or o=NULL
end type
nullableSequence q
q = {1,2,3}
q = "string" -- fine (strings are a subset of sequences)
q = N... | Give a code snippet in #Phix
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your langua... | 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 ... | #Go | Go | func multiply(a, b float64) float64 {
return a * b
} | Give a code snippet in #Go
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 fro... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
⋮
⋮
⋮
⋱
... | #VBScript | VBScript |
build_matrix(7)
Sub build_matrix(n)
Dim matrix()
ReDim matrix(n-1,n-1)
i = 0
'populate the matrix
For row = 0 To n-1
For col = 0 To n-1
If col = i Then
matrix(row,col) = 1
Else
matrix(row,col) = 0
End If
Next
i = i + 1
Next
'display the matrix
For row = 0 To n-1
For col = 0 To n-1
... | Give a code snippet in #VBScript
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mad_Libs | Mad Libs |
This page uses content from Wikipedia. The original article was at Mad Libs. 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)
Mad Libs is a phrasal template word game where one player prompts another... | #D | D | import std.stdio, std.regex, std.algorithm, std.string, std.array;
void main() {
writeln("Enter a story template, terminated by an empty line:");
string story;
while (true) {
auto line = stdin.readln().strip();
if (line.empty) break;
story ~= line ~ "\n";
}
auto re = rege... | Give a code snippet in #D
This page uses content from Wikipedia. The original article was at Mad Libs. 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)
Mad Libs is a phrasal template word game where... | 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
)
)
,
... | #Erlang | Erlang | -module(mutrec).
-export([mutrec/0, f/1, m/1]).
f(0) -> 1;
f(N) -> N - m(f(N-1)).
m(0) -> 0;
m(N) -> N - f(m(N-1)).
mutrec() -> lists:map(fun(X) -> io:format("~w ", [f(X)]) end, lists:seq(0,19)),
io:format("~n", []),
lists:map(fun(X) -> io:format("~w ", [m(X)]) end, lists:seq(0,19)),
io:format("~n"... | Give a code snippet in #Erlang
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/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:... | #Elixir | Elixir | iex(1)> ls = fn dir -> File.ls!(dir) |> Enum.each(&IO.puts &1) end
#Function<6.54118792/1 in :erl_eval.expr/5>
iex(2)> ls.("foo")
bar
:ok
iex(3)> ls.("foo/bar")
1
2
a
b
:ok | Give a code snippet in #Elixir
Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Examp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
numeric digits 1000
runSample(arg)
return
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) public static
BLACK_UPPOINTING_TRIANGLE = '\u25b2'
parse arg ordr filr .
if ordr = '' | ... | Give a code snippet in #NetRexx
Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #Swift | Swift | typealias NodePtr<T> = UnsafeMutablePointer<Node<T>>
class Node<T> {
var value: T
fileprivate var prev: NodePtr<T>?
fileprivate var next: NodePtr<T>?
init(value: T, prev: NodePtr<T>? = nil, next: NodePtr<T>? = nil) {
self.value = value
self.prev = prev
self.next = next
}
}
struct DoublyLinke... | Give a code snippet in #Swift
Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Universal_Turing_machine | Universal Turing machine | One of the foundational mathematical constructs behind computer science
is the universal Turing Machine.
(Alan Turing introduced the idea of such a machine in 1936–1937.)
Indeed one way to definitively prove that a language
is turing-complete
is to implement a universal Turing machine in it.
Task
Simulate such ... | #Prolog | Prolog | turing(Config, Rules, TapeIn, TapeOut) :-
call(Config, IS, _, _, _, _),
perform(Config, Rules, IS, {[], TapeIn}, {Ls, Rs}),
reverse(Ls, Ls1),
append(Ls1, Rs, TapeOut).
perform(Config, Rules, State, TapeIn, TapeOut) :-
call(Config, _, FS, RS, B, Symbols),
( memberchk(State, FS) ->
TapeO... | Give a code snippet in #Prolog
One of the foundational mathematical constructs behind computer science
is the universal Turing Machine.
(Alan Turing introduced the idea of such a machine in 1936–1937.)
Indeed one way to definitively prove that a language
is turing-complete
is to implement a universal Turing machin... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Text_processing/Max_licenses_in_use | Text processing/Max licenses in use | A company currently pays a fixed sum for the use of a particular licensed software package. In determining if it has a good deal it decides to calculate its maximum use of the software from its license management log file.
Assume the software's licensing daemon faithfully records a checkout event when a copy of the ... | #Euphoria | Euphoria | function split(sequence s, integer c)
sequence out
integer first, delim
out = {}
first = 1
while first <= length(s) do
delim = find_from(c, s, first)
if delim = 0 then
delim = length(s) + 1
end if
out = append(out, s[first..delim-1])
first = delim ... | Give a code snippet in #Euphoria
A company currently pays a fixed sum for the use of a particular licensed software package. In determining if it has a good deal it decides to calculate its maximum use of the software from its license management log file.
Assume the software's licensing daemon faithfully records a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #PHP | PHP |
<?php
session_start();
if(isset($_SESSION['number']))
{
$number = $_SESSION['number'];
}
else
{
$_SESSION['number'] = rand(1,10);
}
if(isset($_POST["guess"])){
if($_POST["guess"]){
$guess = htmlspecialchars($_POST['guess']);
echo $guess . "<br />";
if ($guess != $number)
{
ec... | Give a code snippet in #PHP
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #UNIX_Shell | UNIX Shell | #!/bin/sh
if [ -z $1 ]; then exit 1; fi
# weed out multiple erros due to bad year
ncal 1 $1 > /dev/null && \
for m in 01 02 03 04 05 06 07 08 09 10 11 12; do
echo $1-$m-`ncal $m $1 | grep Fr | sed 's/.* \([0-9]\)/\1/'`
done | Give a code snippet in #UNIX_Shell
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24... | christopher/rosetta-code |
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