task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Sum_to_100 | Sum to 100 | Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particular sum (in this iconic case, ... | #Picat | Picat | main =>
L = "23456789",
gen(L,Str),
Exp = parse_term(['1'|Str]),
Exp =:= 100,
println(['1'|Str]).
gen(L@[_],Str) => Str = L.
gen([D|Ds],Str) ?=> Str = [D|StrR], gen(Ds,StrR). % no operator
gen([D|Ds],Str) ?=> Str = ['+',D|StrR], gen(Ds,StrR). % insert +
gen([D|Ds],Str) => Str = ['-',D|StrR], g... | Give a code snippet in #Picat
Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particular... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #Smalltalk | Smalltalk | |a b c|
a := #(1 2 3 4 5).
b := #(6 7 8 9 10).
c := a,b.
c displayNl. | Give a code snippet in #Smalltalk
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| 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... | #Scilab | Scilab | n=15
t=zeros(1,n+2)
t(1)=1
for i=1:n
for j=i+1:-1:2
t(j)=t(j)+t(j-1)
end
t(i+1)=t(i)
for j=i+2:-1:2
t(j)=t(j)+t(j-1)
end
disp(t(i+1)-t(i))
end | Give a code snippet in #Scilab
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/Polymorphism | Polymorphism | Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref savelog symbols binary
-- -----------------------------------------------------------------------------
class RCPolymorphism public final
method main(args = String[]) public constant
parry = [Point -
Point() ... | Give a code snippet in #NetRexx
Task
Create two classes Point(x,y) and Circle(x,y,r) with a polymorphic function print, accessors for (x,y,r), copy constructor, assignment and destructor and every possible default constructors
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_strings | Binary strings | Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings according to Wikipedia) for those la... | #BQN | BQN | name ← "" | Give a code snippet in #BQN
Many languages have powerful and useful (binary safe) string manipulation functions, while others don't, making it harder for these languages to accomplish some tasks.
This task is about creating functions to handle binary strings (strings made of arbitrary bytes, i.e. byte strings accordi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Summarize_and_say_sequence | Summarize and say sequence | There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 311311222110 ...
The terms generat... | #PicoLisp | PicoLisp | (de selfRefSequence (Seed)
(let L (mapcar format (chop Seed))
(make
(for (Cache NIL (not (idx 'Cache L T)))
(setq L
(las (flip (sort (copy (link L))))) ) ) ) ) )
(let Res NIL
(for Seed 1000000
(let N (length (selfRefSequence Seed))
(cond
((> ... | Give a code snippet in #PicoLisp
There are several ways to generate a self-referential sequence. One very common one (the Look-and-say sequence) is to start with a positive integer, then generate the next term by concatenating enumerated groups of adjacent alike digits:
0, 10, 1110, 3110, 132110, 1113122110, 3... | christopher/rosetta-code | |
http://rosettacode.org/wiki/First-class_functions | First-class functions | A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming:
Create new functions from preexisting functions at run-time
Store functions in collections
Use functions as arguments to other functions
Use functions as retu... | #GAP | GAP | # Function composition
Composition := function(f, g)
local h;
h := function(x)
return f(g(x));
end;
return h;
end;
# Apply each function in list u, to argument x
ApplyList := function(u, x)
local i, n, v;
n := Size(u);
v := [ ];
for i in [1 .. n] do
v[i] := u[i](x);
od;
return v;
end;
# ... | Give a code snippet in #GAP
A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming:
Create new functions from preexisting functions at run-time
Store functions in collections
Use functions as arguments to other fun... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tonelli-Shanks_algorithm | Tonelli-Shanks algorithm |
This page uses content from Wikipedia. The original article was at Tonelli-Shanks algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In computational number theory, the Tonelli–Shanks algor... | #C | C | #include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
uint64_t modpow(uint64_t a, uint64_t b, uint64_t n) {
uint64_t x = 1, y = a;
while (b > 0) {
if (b % 2 == 1) {
x = (x * y) % n; // multiplying with base
}
y = (y * y) % n; // squaring the base
b /= 2;
}... | Give a code snippet in #C
This page uses content from Wikipedia. The original article was at Tonelli-Shanks algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In computational number theor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Numerical_integration | Numerical integration | Write functions to calculate the definite integral of a function ƒ(x) using all five of the following methods:
rectangular
left
right
midpoint
trapezium
Simpson's
composite
Your functions should take in the upper and lower bounds (a and b), and the number of approximations to make in that range (n).
Assume t... | #Nim | Nim | type Function = proc(x: float): float
type Rule = proc(f: Function; x, h: float): float
proc leftRect(f: Function; x, h: float): float =
f(x)
proc midRect(f: Function; x, h: float): float =
f(x + h/2.0)
proc rightRect(f: Function; x, h: float): float =
f(x + h)
proc trapezium(f: Function; x, h: float): fl... | Give a code snippet in #Nim
Write functions to calculate the definite integral of a function ƒ(x) using all five of the following methods:
rectangular
left
right
midpoint
trapezium
Simpson's
composite
Your functions should take in the upper and lower bounds (a and b), and the number of approximations to make... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_comparison | Integer comparison |
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 |... | #BASIC | BASIC |
INPUT "Enter first number " ,a
INPUT "Enter second number " ,b
IF a < b THEN PRINT a ," is less than ", b
IF a = b THEN PRINT a, " is equal to ", b
IF a > b THEN PRINT a, " is greater than ", b | Give a code snippet in #BASIC
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/Set | Set |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an... | #PowerShell | PowerShell |
[System.Collections.Generic.HashSet[object]]$set1 = 1..4
[System.Collections.Generic.HashSet[object]]$set2 = 3..6
# Operation + Definition + Result
#--------------------------------+---------------------+-------------------------
$set1.UnionWith($set2) # Union ... | Give a code snippet in #PowerShell
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Miller%E2%80%93Rabin_primality_test | Miller–Rabin primality test |
This page uses content from Wikipedia. The original article was at Miller–Rabin primality test. 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)
The Miller–Rabin primality test or Rabin–Miller prima... | #Julia | Julia |
witnesses(n::Union(Uint8,Int8,Uint16,Int16)) = (2,3)
witnesses(n::Union(Uint32,Int32)) = n < 1373653 ? (2,3) : (2,7,61)
witnesses(n::Union(Uint64,Int64)) =
n < 1373653 ? (2,3) :
n < 4759123141 ? (2,7,61) :
n < 2152302898747 ? (2,3,5,7,11) :
n < 3474749660383 ? (2,3,5,7... | Give a code snippet in #Julia
This page uses content from Wikipedia. The original article was at Miller–Rabin primality test. 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)
The Miller–Rabin prima... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
Other tasks re... | #Fortran | Fortran | program test_repeat
write (*, '(a)') repeat ('ha', 5)
end program test_repeat | Give a code snippet in #Fortran
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calkin-Wilf_sequence | Calkin-Wilf sequence | The Calkin-Wilf sequence contains every nonnegative rational number exactly once.
It can be calculated recursively as follows:
a1 = 1
an+1 = 1/(2⌊an⌋+1-an) for n > 1
Task part 1
Show on this page terms 1 through 20 of the Calkin-Wilf sequence.
To avoid floating point error, you may want to ... | #ALGOL_68 | ALGOL 68 | BEGIN
# Show elements 1-20 of the Calkin-Wilf sequence as rational numbers #
# also show the position of a specific element in the seuence #
# Uses code from the Arithmetic/Rational #
# & Continued fraction/Arithmetic/Construct from rational number... | Give a code snippet in #ALGOL_68
The Calkin-Wilf sequence contains every nonnegative rational number exactly once.
It can be calculated recursively as follows:
a1 = 1
an+1 = 1/(2⌊an⌋+1-an) for n > 1
Task part 1
Show on this page terms 1 through 20 of the Calkin-Wilf sequence.
To avoid floa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pascal%27s_triangle | Pascal's triangle | Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is either 1 or the sum of the two elemen... | #TI-83_BASIC | TI-83 BASIC | PROGRAM:PASCALTR
:Lbl IN
:ClrHome
:Disp "NUMBER OF ROWS"
:Input N
:If N < 1:Goto IN
:{N,N}→dim([A])
:"CHEATING TO MAKE IT FASTER"
:For(I,1,N)
:1→[A](1,1)
:End
:For(I,2,N)
:For(J,2,I)
:[A](I-1,J-1)+[A](I-1,J)→[A](I,J)
:End
:End
:[A] | Give a code snippet in #TI-83_BASIC
Pascal's triangle is an arithmetic and geometric figure often associated with the name of Blaise Pascal, but also studied centuries earlier in India, Persia, China and elsewhere.
Its first few rows look like this:
1
1 1
1 2 1
1 3 3 1
where each element of each row is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Repeat_a_string | Repeat a string | Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => "*****").
Other tasks re... | #Oz | Oz | declare
fun {Repeat Xs N}
if N > 0 then
{Append Xs {Repeat Xs N-1}}
else
nil
end
end
in
{System.showInfo {Repeat "Ha" 5}} | Give a code snippet in #Oz
Take a string and repeat it some number of times.
Example: repeat("ha", 5) => "hahahahaha"
If there is a simpler/more efficient way to repeat a single “character” (i.e. creating a string filled with a certain character), you might want to show that as well (i.e. repeat-char("*", 5) => ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Short-circuit_evaluation | Short-circuit evaluation | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable resources without side effects, an... | #Logo | Logo | and [notequal? :x 0] [1/:x > 3]
(or [:x < 0] [:y < 0] [sqrt :x + sqrt :y < 3]) | Give a code snippet in #Logo
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable reso... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Stooge_sort | Sorting algorithms/Stooge 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
... | #Wren | Wren | var stoogeSort // recursive
stoogeSort = Fn.new { |a, i, j|
if (a[j] < a[i]) {
var t = a[i]
a[i] = a[j]
a[j] = t
}
if (j - i > 1) {
var t = ((j - i + 1)/3).floor
stoogeSort.call(a, i, j - t)
stoogeSort.call(a, i + t, j)
stoogeSort.call(a, i, j - t)
... | Give a code snippet in #Wren
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 sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Amb | Amb | Define and give an example of the Amb operator.
The Amb operator (short for "ambiguous") expresses nondeterminism. This doesn't refer to randomness (as in "nondeterministic universe") but is closely related to the term as it is used in automata theory ("non-deterministic finite automaton").
The Amb operator takes a v... | #PureBasic | PureBasic | Procedure Words_Ok(String1.s, String2.s)
If Mid(String1,Len(String1),1)=Mid(String2,1,1)
ProcedureReturn #True
EndIf
ProcedureReturn #False
EndProcedure
Procedure.s Amb(Array A.s(1), Array B.s(1), Array C.s(1), Array D.s(1))
Protected a, b, c, d
For a=0 To ArraySize(A())
For b=0 To ArraySize(B())
... | Give a code snippet in #PureBasic
Define and give an example of the Amb operator.
The Amb operator (short for "ambiguous") expresses nondeterminism. This doesn't refer to randomness (as in "nondeterministic universe") but is closely related to the term as it is used in automata theory ("non-deterministic finite autom... | christopher/rosetta-code | |
http://rosettacode.org/wiki/ISBN13_check_digit | ISBN13 check digit | Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing:
978-1734314502 (good)
... | #AppleScript | AppleScript | -------------------- ISBN13 CHECK DIGIT --------------------
-- isISBN13 :: String -> Bool
on isISBN13(s)
script digitValue
on |λ|(c)
if isDigit(c) then
{c as integer}
else
{}
end if
end |λ|
end script
set digits to conc... | Give a code snippet in #AppleScript
Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Dimensions | Terminal control/Dimensions | Determine the height and width of the terminal, and store this information into variables for subsequent use.
| #REXX | REXX | width = 'tput'( 'cols' )
height = 'tput'( 'lines' )
say 'The terminal is' width 'characters wide'
say 'and has' height 'lines' | Give a code snippet in #REXX
Determine the height and width of the terminal, and store this information into variables for subsequent use.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Mouse_position | Mouse position | Task
Get the current location of the mouse cursor relative to the active window.
Please specify if the window may be externally created.
| #Racket | Racket |
#lang racket/gui
(define-values [point _] (get-current-mouse-state))
(send point get-x)
(send point get-y)
| Give a code snippet in #Racket
Task
Get the current location of the mouse cursor relative to the active window.
Please specify if the window may be externally created.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Seven-sided_dice_from_five-sided_dice | Seven-sided dice from five-sided dice | Task
(Given an equal-probability generator of one of the integers 1 to 5
as dice5), create dice7 that generates a pseudo-random integer from
1 to 7 in equal probability using only dice5 as a source of random
numbers, and check the distribution for at least one million calls using the function created in Simple R... | #Nim | Nim | import random, tables
proc dice5(): int = rand(1..5)
proc dice7(): int =
while true:
let val = 5 * dice5() + dice5() - 6
if val < 21:
return val div 3 + 1
proc checkDist(f: proc(): int; repeat: Positive; tolerance: float) =
var counts: CountTable[int]
for _ in 1..repeat:
counts.inc... | Give a code snippet in #Nim
Task
(Given an equal-probability generator of one of the integers 1 to 5
as dice5), create dice7 that generates a pseudo-random integer from
1 to 7 in equal probability using only dice5 as a source of random
numbers, and check the distribution for at least one million calls using the f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Odd_word_problem | Odd word problem | Task
Write a program that solves the odd word problem with the restrictions given below.
Description
You are promised an input stream consisting of English letters and punctuations.
It is guaranteed that:
the words (sequence of consecutive letters) are delimited by one and only one punctuation,
the stream will... | #Haskell | Haskell | import System.IO
(BufferMode(..), getContents, hSetBuffering, stdin, stdout)
import Data.Char (isAlpha)
split :: String -> (String, String)
split = span isAlpha
parse :: String -> String
parse [] = []
parse l =
let (a, w) = split l
(b, x) = splitAt 1 w
(c, y) = split x
(d, z) = splitAt 1 ... | Give a code snippet in #Haskell
Task
Write a program that solves the odd word problem with the restrictions given below.
Description
You are promised an input stream consisting of English letters and punctuations.
It is guaranteed that:
the words (sequence of consecutive letters) are delimited by one and only ... | 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
| #Sather | Sather | class ZIPPER{K,E} is
zip(k:ARRAY{K}, e:ARRAY{E}) :MAP{K, E}
pre k.size = e.size
is
m :MAP{K, E} := #;
loop m[k.elt!] := e.elt!; end;
return m;
end;
end;
class MAIN is
main is
keys:ARRAY{STR} := |"one", "three", "four"|;
values:ARRAY{INT} := |1, 3, 4|;
m ::= ZIPPER{STR,INT}::... | Give a code snippet in #Sather
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/Elementary_cellular_automaton/Infinite_length | Elementary cellular automaton/Infinite length | The purpose of this task is to create a version of an Elementary cellular automaton whose number of cells is only limited by the memory size of the computer.
To be precise, consider the state of the automaton to be made of an infinite number of cells, but with a bounded support. In other words, to describe the state o... | #Wren | Wren | import "/fmt" for Fmt
var addNoCells = Fn.new { |s|
var l = (s[0] == "*") ? "." : "*"
var r = (s[-1] == "*") ? "." : "*"
for (i in 0..1) {
s.insert(0, l)
s.add(r)
}
}
var step = Fn.new { |cells, rule|
var newCells = []
for (i in 0...cells.count - 2) {
var bin = 0
... | Give a code snippet in #Wren
The purpose of this task is to create a version of an Elementary cellular automaton whose number of cells is only limited by the memory size of the computer.
To be precise, consider the state of the automaton to be made of an infinite number of cells, but with a bounded support. In other ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zero_to_the_zero_power | Zero to the zero power | Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or 0^0 at compile time, ... | #Applesoft_BASIC | Applesoft BASIC | ]? 0^0
1 | Give a code snippet in #Applesoft_BASIC
Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pick_random_element | Pick random element | Demonstrate how to pick a random element from a list.
| #Wren | Wren | import "random" for Random
var rand = Random.new()
var colors = ["red", "green", "blue", "yellow", "pink"]
for (i in 0..4) System.print(colors[rand.int(colors.count)]) | Give a code snippet in #Wren
Demonstrate how to pick a random element from a list.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fractal_tree | Fractal tree | Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| #Java | Java | import java.awt.Color;
import java.awt.Graphics;
import javax.swing.JFrame;
public class FractalTree extends JFrame {
public FractalTree() {
super("Fractal Tree");
setBounds(100, 100, 800, 600);
setResizable(false);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
private voi... | Give a code snippet in #Java
Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fairshare_between_two_and_more | Fairshare between two and more | The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (Football penalty shoot-outs for example, might
not favour t... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[Fairshare]
Fairshare[n_List, b_Integer : 2] := Fairshare[#, b] & /@ n
Fairshare[n_Integer, b_Integer : 2] := Mod[Total[IntegerDigits[n, b]], b]
Fairshare[Range[0, 24], 2]
Fairshare[Range[0, 24], 3]
Fairshare[Range[0, 24], 5]
Fairshare[Range[0, 24], 11] | Give a code snippet in #Mathematica_.2F_Wolfram_Language
The Thue-Morse sequence is a sequence of ones and zeros that if two people
take turns in the given order, the first persons turn for every '0' in the
sequence, the second for every '1'; then this is shown to give a fairer, more
equitable sharing of resources. (F... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Look-and-say_sequence | Look-and-say sequence | The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1, 11, 21, 1211, 11122... | #C | C | #include <stdio.h>
#include <stdlib.h>
int main()
{
char *a = malloc(2), *b = 0, *x, c;
int cnt, len = 1;
for (sprintf(a, "1"); (b = realloc(b, len * 2 + 1)); a = b, b = x) {
puts(x = a);
for (len = 0, cnt = 1; (c = *a); ) {
if (c == *++a)
cnt++;
else if (c) {
len += sprintf(b + len, "%d%c", cn... | Give a code snippet in #C
The Look and say sequence is a recursively defined sequence of numbers studied most notably by John Conway.
The look-and-say sequence is also known as the Morris Number Sequence, after cryptographer Robert Morris, and the puzzle What is the next number in the sequence 1, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calculating_the_value_of_e | Calculating the value of e | Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| #Prolog | Prolog |
% Calculate the value e = exp 1
% Use Newton's method: x0 = 2; y = x(2 - ln x)
tolerance(1e-15).
exp1_iter(L) :-
lazy_list(newton, 2, L).
newton(X0, X1, X1) :-
X1 is X0*(2 - log(X0)).
e([X1, X2|_], X1) :- tolerance(Eps), abs(X2 - X1) < Eps.
e([_|Xs], E) :- e(Xs, E).
main :-
exp1_iter(Iter),
... | Give a code snippet in #Prolog
Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Entropy | Entropy | Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary), the Shannon entropy of X in bit... | #ooRexx | ooRexx | /* REXX */
Numeric Digits 16
Parse Arg s
If s='' Then
s="1223334444"
occ.=0
chars=''
n=0
cn=0
Do i=1 To length(s)
c=substr(s,i,1)
If pos(c,chars)=0 Then Do
cn=cn+1
chars=chars||c
End
occ.c=occ.c+1
n=n+1
End
do ci=1 To cn
c=substr(chars,ci,1)
p.c=occ.c/n
/* say c p.c */
End
e=0
Do ci=1 To... | Give a code snippet in #ooRexx
Task
Calculate the Shannon entropy H of a given input string.
Given the discrete random variable
X
{\displaystyle X}
that is a string of
N
{\displaystyle N}
"symbols" (total characters) consisting of
n
{\displaystyle n}
different characters (n=2 for binary),... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_length | String length | Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme containing combining characters.
F... | #Stata | Stata | scalar s="Ἐν ἀρχῇ ἐποίησεν ὁ θεὸς τὸν οὐρανὸν καὶ τὴν γῆν"
di strlen(s)
97
di ustrlen(s)
47 | Give a code snippet in #Stata
Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme cont... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stream_merge | Stream merge | 2-stream merge
Read two sorted streams of items from external source (e.g. disk, or network), and write one stream of sorted items to external sink.
Common algorithm: keep 1 buffered item from each source, select minimal of them, write it, fetch another item from that stream from which the written item was.
N-strea... | #Go | Go | package main
import (
"container/heap"
"fmt"
"io"
"log"
"os"
"strings"
)
var s1 = "3 14 15"
var s2 = "2 17 18"
var s3 = ""
var s4 = "2 3 5 7"
func main() {
fmt.Print("merge2: ")
merge2(
os.Stdout,
strings.NewReader(s1),
strings.NewReader(s2))
fmt.Println... | Give a code snippet in #Go
2-stream merge
Read two sorted streams of items from external source (e.g. disk, or network), and write one stream of sorted items to external sink.
Common algorithm: keep 1 buffered item from each source, select minimal of them, write it, fetch another item from that stream from which th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rep-string | Rep-string | Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For e... | #Kotlin | Kotlin | // version 1.0.6
fun repString(s: String): MutableList<String> {
val reps = mutableListOf<String>()
if (s.length < 2) return reps
for (c in s) if (c != '0' && c != '1') throw IllegalArgumentException("Not a binary string")
for (len in 1..s.length / 2) {
val t = s.take(len)
val n = s.le... | Give a code snippet in #Kotlin
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at lea... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Decode | Roman numerals/Decode | Task
Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer.
You don't need to validate the form of the Roman numeral.
Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately,
starting with the leftmost decima... | #Modula-2 | Modula-2 | MODULE RomanNumerals;
FROM InOut IMPORT WriteString, WriteCard, WriteLn;
FROM Strings IMPORT Length;
(* Convert given Roman numeral to binary *)
PROCEDURE DecodeRoman(s: ARRAY OF CHAR): CARDINAL;
VAR i, d, len, acc: CARDINAL;
PROCEDURE Digit(d: CHAR): CARDINAL;
BEGIN
CASE CHR( BITSET(ORD(d)) + B... | Give a code snippet in #Modula-2
Task
Create a function that takes a Roman numeral as its argument and returns its value as a numeric decimal integer.
You don't need to validate the form of the Roman numeral.
Modern Roman numerals are written by expressing each decimal digit of the number to be encoded separately,
... | 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... | #Python | Python | #!/usr/bin/env python
import sys
def main():
program = sys.argv[0]
print("Program: %s" % program)
if __name__ == "__main__":
main() | Give a code snippet in #Python
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parallel_calculations | Parallel calculations | Many programming languages allow you to specify computations to be run in parallel.
While Concurrent computing is focused on concurrency,
the purpose of this task is to distribute time-consuming calculations
on as many CPUs as possible.
Assume we have a collection of numbers, and want to find the one
with the largest ... | #Prolog | Prolog | threaded_decomp(Number,ID):-
thread_create(
(prime_decomp(Number,Y),
thread_exit((Number,Y)))
,ID,[]).
threaded_decomp_list(List,Erg):-
maplist(threaded_decomp,List,IDs),
maplist(thread_join,IDs,Results),
maplist(pack_exit_out,Results,Smallest_Factors_List),
largest_min_factor(Smallest_Fa... | Give a code snippet in #Prolog
Many programming languages allow you to specify computations to be run in parallel.
While Concurrent computing is focused on concurrency,
the purpose of this task is to distribute time-consuming calculations
on as many CPUs as possible.
Assume we have a collection of numbers, and want t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #Dyalect | Dyalect | var n = 0
while true {
n += 1
print(n)
} | Give a code snippet in #Dyalect
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Walk_a_directory/Non-recursively | Walk a directory/Non-recursively | Task
Walk a given directory and print the names of files matching a given pattern.
(How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?)
Note: This task is for non-recursive methods. These tasks should read a single directory, not an entire directory tree.
... | #Batch_File | Batch File | dir /b "%windir%\system32\*.exe" | Give a code snippet in #Batch_File
Task
Walk a given directory and print the names of files matching a given pattern.
(How is "pattern" defined? substring match? DOS pattern? BASH pattern? ZSH pattern? Perl regular expression?)
Note: This task is for non-recursive methods. These tasks should read a single direct... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Test_integerness | Test integerness | Mathematically,
the integers Z are included in the rational numbers Q,
which are included in the real numbers R,
which can be generalized to the complex numbers C.
This means that each of those larger sets, and the data types used to represent them, include some integers.
Task[edit]
Given a rational, real, or co... | #Ruby | Ruby |
class Numeric
def to_i?
self == self.to_i rescue false
end
end
# Demo
ar = [25.000000, 24.999999, 25.000100, -2.1e120, -5e-2, # Floats
Float::NAN, Float::INFINITY, # more Floats
2r, 2.5r, # Rationals
2+0i, 2+0.0i, 5-5i] ... | Give a code snippet in #Ruby
Mathematically,
the integers Z are included in the rational numbers Q,
which are included in the real numbers R,
which can be generalized to the complex numbers C.
This means that each of those larger sets, and the data types used to represent them, include some integers.
Task[edit]... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Colorful_numbers | Colorful numbers | A colorful number is a non-negative base 10 integer where the product of every sub group of consecutive digits is unique.
E.G.
24753 is a colorful number. 2, 4, 7, 5, 3, (2×4)8, (4×7)28, (7×5)35, (5×3)15, (2×4×7)56, (4×7×5)140, (7×5×3)105, (2×4×7×5)280, (4×7×5×3)420, (2×4×7×5×3)840
Every product is unique.
2346 ... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | ClearAll[ColorfulNumberQ]
ColorfulNumberQ[n_Integer?NonNegative] := Module[{digs, parts},
If[n > 98765432,
False
,
digs = IntegerDigits[n];
parts = Partition[digs, #, 1] & /@ Range[1, Length[digs]];
parts //= Catenate;
parts = Times @@@ parts;
DuplicateFreeQ[parts]
]
]
Multicolumn[Select[Ran... | Give a code snippet in #Mathematica.2FWolfram_Language
A colorful number is a non-negative base 10 integer where the product of every sub group of consecutive digits is unique.
E.G.
24753 is a colorful number. 2, 4, 7, 5, 3, (2×4)8, (4×7)28, (7×5)35, (5×3)15, (2×4×7)56, (4×7×5)140, (7×5×3)105, (2×4×7×5)280, (4×7×5×... | 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.
| #Ceylon | Ceylon | alias Matrix => Integer[][];
void printMatrix(Matrix m) {
value strings = m.collect((row) => row.collect(Integer.string));
value maxLength = max(expand(strings).map(String.size)) else 0;
value padded = strings.collect((row) => row.collect((s) => s.padLeading(maxLength)));
for (row in padded) {
print("[``", ".jo... | Give a code snippet in #Ceylon
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/Inheritance/Multiple | Inheritance/Multiple | Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePhone, then write a class Camer... | #Perl | Perl | package Camera;
#functions go here...
1; | Give a code snippet in #Perl
Multiple inheritance allows to specify that one class is a subclass of several other classes.
Some languages allow multiple inheritance for arbitrary classes, others restrict it to interfaces, some don't allow it at all.
Task
Write two classes (or interfaces) Camera and MobilePho... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Balanced_brackets | Balanced brackets | Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nest.
Examples
(empty) ... | #Rust | Rust | extern crate rand;
trait Balanced {
/// Returns true if the brackets are balanced
fn is_balanced(&self) -> bool;
}
impl<'a> Balanced for str {
fn is_balanced(&self) -> bool {
let mut count = 0;
for bracket in self.chars() {
let change = match bracket {
'[' =... | Give a code snippet in #Rust
Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-ne... | 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.
| #Clojure | Clojure |
(use '(incanter core stats charts io))
(defn Arquimidean-function
[a b theta]
(+ a (* theta b)))
(defn transform-pl-xy [r theta]
(let [x (* r (sin theta))
y (* r (cos theta))]
[x y]))
(defn arq-spiral [t] (transform-pl-xy (Arquimidean-function 0 7 t) t))
(view (parametric-plot arq-spiral 0 (... | Give a code snippet in #Clojure
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/Write_entire_file | Write entire file | Task
(Over)write a file so that it contains a string.
The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.
| #VBScript | VBScript |
Set objFSO = CreateObject("Scripting.FileSystemObject")
SourceFile = objFSO.GetParentFolderName(WScript.ScriptFullName) & "\out.txt"
Content = "(Over)write a file so that it contains a string." & vbCrLf &_
"The reverse of Read entire file—for when you want to update or create a file which you would read in its en... | Give a code snippet in #VBScript
Task
(Over)write a file so that it contains a string.
The reverse of Read entire file—for when you want to update or create a file which you would read in its entirety all at once.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Huffman_coding | Huffman coding | Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could just encode each letter wi... | #M2000_Interpreter | M2000 Interpreter |
Module Huffman {
comp=lambda (a, b) ->{
=array(a, 0)<array(b, 0)
}
module InsertPQ (a, n, &comp) {
if len(a)=0 then stack a {data n} : exit
if comp(n, stackitem(a)) then stack a {push n} : exit
stack a {
push n
t=2:... | Give a code snippet in #M2000_Interpreter
Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sockets | Sockets | For this exercise a program is open a socket to localhost on port 256 and send the message "hello socket world" before closing the socket.
Catching any exceptions or errors is not required.
| #C.2B.2B | C++ | //compile with g++ main.cpp -lboost_system -pthread
#include <boost/asio.hpp>
int main()
{
boost::asio::io_context io_context;
boost::asio::ip::tcp::socket sock(io_context);
boost::asio::ip::tcp::resolver resolver(io_context);
boost::asio::ip::tcp::resolver::query query("localhost", "4321");
boost::asi... | Give a code snippet in #C.2B.2B
For this exercise a program is open a socket to localhost on port 256 and send the message "hello socket world" before closing the socket.
Catching any exceptions or errors is not required.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_a_quadratic_function | Roots of a quadratic function | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your program must correctly handle n... | #Elixir | Elixir | defmodule Quadratic do
def roots(a, b, c) do
IO.puts "Roots of a quadratic function (#{a}, #{b}, #{c})"
d = b * b - 4 * a * c
a2 = a * 2
cond do
d > 0 ->
sd = :math.sqrt(d)
IO.puts " the real roots are #{(- b + sd) / a2} and #{(- b - sd) / a2}"
d == 0 ->
IO.puts " ... | Give a code snippet in #Elixir
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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
... | #Tcl | Tcl | proc is_prime n {
if {$n <= 1} {return false}
if {$n == 2} {return true}
if {$n % 2 == 0} {return false}
for {set i 3} {$i <= sqrt($n)} {incr i 2} {
if {$n % $i == 0} {return false}
}
return true
} | Give a code snippet in #Tcl
Task
Write a boolean function that tells whether a given integer is prime.
Remember that 1 and all non-positive numbers are not prime.
Use trial division.
Even numbers greater than 2 may be eliminated right away.
A loop from 3 to √ n will suffice, but other loops a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Yahoo!_search_interface | Yahoo! search interface | Create a class for searching Yahoo! results.
It must implement a Next Page method, and read URL, Title and Content from results.
| #Gambas | Gambas | Public Sub Form_Open()
Dim hWebView As WebView
Me.Arrangement = Arrange.Fill
Me.Maximized = True
Me.Title = "Yahoo! search interface"
hWebView = New WebView(Me)
hWebView.Expand = True
hWebView.URL = "https://www.yahoo.com"
End | Give a code snippet in #Gambas
Create a class for searching Yahoo! results.
It must implement a Next Page method, and read URL, Title and Content from results.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Input | Non-decimal radices/Input | It is common to have a string containing a number written in some format, with the most common ones being decimal, hexadecimal, octal and binary. Such strings are found in many places (user interfaces, configuration files, XML data, network protocols, etc.)
This task requires parsing of such a string (which may be ass... | #Ring | Ring |
see number("0") + nl
see number("123456789") + nl
see number("-987654321") + nl
| Give a code snippet in #Ring
It is common to have a string containing a number written in some format, with the most common ones being decimal, hexadecimal, octal and binary. Such strings are found in many places (user interfaces, configuration files, XML data, network protocols, etc.)
This task requires parsing of s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Wren | Wren | // To use recursion definition and declaration must be on separate lines
var Ackermann
Ackermann = Fn.new {|m, n|
if (m == 0) return n + 1
if (n == 0) return Ackermann.call(m - 1, 1)
return Ackermann.call(m - 1, Ackermann.call(m, n - 1))
}
var pairs = [ [1, 3], [2, 3], [3, 3], [1, 5], [2, 5], [3, 5] ]
fo... | Give a code snippet in #Wren
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Excel | Excel |
=fact(5)
| Give a code snippet in #Excel
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newbie | Hello world/Newbie | Task
Guide a new user of a language through the steps necessary
to install the programming language and selection of a text editor if needed,
to run the languages' example in the Hello world/Text task.
Assume the language-newbie is a programmer in another language.
Assume the language-newbie is competent in install... | #Perl | Perl | =head1 Obtaining perl
On the majority of UNIX and UNIX-like operating systems
(Linux, Solaris, AIX, HPUX, et cetera), perl will already be installed.
Mac OS X also ships with perl.
Note that "Perl" refers to the language
while "perl" refers to the interpreter used to run Perl programs.
Windows does not ship wit... | Give a code snippet in #Perl
Task
Guide a new user of a language through the steps necessary
to install the programming language and selection of a text editor if needed,
to run the languages' example in the Hello world/Text task.
Assume the language-newbie is a programmer in another language.
Assume the language-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file | Create a file | In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Stata | Stata | file open f using output.txt, write replace
file close f
mkdir docs
file open f using \output.txt, write replace
file close f
mkdir \docs | Give a code snippet in #Stata
In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_management | Window management | Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window of interest may or may not have b... | #Oz | Oz | declare
[QTk] = {Module.link ['x-oz://system/wp/QTk.ozf']}
%% The messages that can be sent to the windows.
WindowActions =
[hide show close
iconify deiconify
maximize restore
set(minsize:minsize(width:400 height:400))
set(minsize:minsize(width:200 height:200))
set(geometry:geometry(x:0 y:0))
... | Give a code snippet in #Oz
Treat windows or at least window identities as first class objects.
Store window identities in variables, compare them for equality.
Provide examples of performing some of the following:
hide,
show,
close,
minimize,
maximize,
move, and
resize a window.
The window of in... | 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
| #KonsolScript | KonsolScript | function main() {
Konsol:Log("Hello world!")
} | Give a code snippet in #KonsolScript
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Run-length_encoding | Run-length encoding | Run-length encoding
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression... | #REXX | REXX | /*REXX program encodes and displays a string by using a run─length encoding scheme. */
parse arg input . /*normally, input would be in a file. */
default= 'WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW'
if input=='' | input=="," then input= default /*Not spec... | Give a code snippet in #REXX
Run-length encoding
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a funct... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #Clojure | Clojure |
(with-open [r (clojure.java.io/reader "some-file.txt")]
(doseq [l (line-seq r)]
(println l)))
| Give a code snippet in #Clojure
Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Conditional_structures | Conditional structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common conditional structures include ... | #XSLT | XSLT | <xsl:if test="condition">
<!-- executed if XPath expression evaluates to true -->
</xsl:if> | Give a code snippet in #XSLT
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Record_sound | Record sound | Record a monophonic 16-bit PCM sound into either memory space, a file or array.
(This task neglects to specify the sample rate, and whether to use signed samples.
The programs in this page might use signed 16-bit or unsigned 16-bit samples, at 8000 Hz, 44100 Hz, or any other sample rate.
Therefore, these programs migh... | #Scala | Scala | import java.io.{File, IOException}
import javax.sound.sampled.{AudioFileFormat, AudioFormat, AudioInputStream}
import javax.sound.sampled.{AudioSystem, DataLine, LineUnavailableException, TargetDataLine}
object SoundRecorder extends App {
// record duration, in milliseconds
final val RECORD_TIME = 60000 // 1 minu... | Give a code snippet in #Scala
Record a monophonic 16-bit PCM sound into either memory space, a file or array.
(This task neglects to specify the sample rate, and whether to use signed samples.
The programs in this page might use signed 16-bit or unsigned 16-bit samples, at 8000 Hz, 44100 Hz, or any other sample rate.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mandelbrot_set | Mandelbrot set | Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate it .
| #Vedit_macro_language | Vedit macro language | #1 =-21000 // left edge = -2.1
#2 = 15000 // right edge = 1.5
#3 = 15000 // top edge = 1.5
#4 =-15000 // bottom edge = -1.5
#5 = 200 // max iteration depth
#6 = 350 // x step size
#7 = 750 // y step size
Buf_Switch(Buf_Fr... | Give a code snippet in #Vedit_macro_language
Mandelbrot set
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw the Mandelbrot set.
Note that there are many algorithms to draw Mandelbrot set and there are many functions which generate ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Colour_pinstripe/Display | Colour pinstripe/Display | The task is to create 1 pixel wide coloured vertical pinstripes with a sufficient number of pinstripes to span the entire width of the graphics display.
The pinstripes should either follow the system palette sequence, or a sequence that includes:
black, red, green, blue, magenta, cyan, yellow, and ... | #FreeBASIC | FreeBASIC | ' version 14-03-2017
' compile with: fbc -s console
' or compile with: fbc -s gui
Dim As UInteger ps, col, h, w, x, y1, y2
ScreenInfo w, h
' create display size window, 8bit color (palette), no frame
ScreenRes w, h, 8,, 8
h = h \ 4 : y2 = h -1
For ps = 1 To 4
col = 0
For x = 0 To (w - ps -1) Step ps
... | Give a code snippet in #FreeBASIC
The task is to create 1 pixel wide coloured vertical pinstripes with a sufficient number of pinstripes to span the entire width of the graphics display.
The pinstripes should either follow the system palette sequence, or a sequence that includes:
black, red, green, blue, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping | Tokenize a string with escaping | Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for splitting:
The fields that were s... | #8080_Assembly | 8080 Assembly | org 100h
jmp demo
;;; Routine to split a 0-terminated string
;;; Input: B=separator, C=escape, HL=string pointer.
;;; Output: DE=end of list of strings
;;; The split strings are stored in place.
split: mov d,h ; Set DE = output pointer
mov e,l
snext: mov a,m ; Get current input character
inx h ; Advance input p... | Give a code snippet in #8080_Assembly
Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Letter_frequency | Letter frequency | Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequen... | #Elixir | Elixir | file = hd(System.argv)
File.read!(file)
|> String.upcase
|> String.graphemes
|> Enum.filter(fn c -> c =~ ~r/[A-Z]/ end)
|> Enum.reduce(Map.new, fn c,acc -> Map.update(acc, c, 1, &(&1+1)) end)
|> Enum.sort_by(fn {_k,v} -> -v end)
|> Enum.each(fn {k,v} -> IO.puts "#{k} #{v}" end) | Give a code snippet in #Elixir
Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (as... | 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.
... | #Pike | Pike | int main(){
for(int i = 1; i <= 5; i++){
for(int j=1; j <= i; j++){
write("*");
}
write("\n");
}
} | Give a code snippet in #Pike
“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 structur... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_length | Array length | Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I befo... | #Onyx | Onyx | [`apple' `orange'] length # leaves 2 on top of the stack | Give a code snippet in #Onyx
Task
Determine the amount of elements in an array.
As an example use an array holding the strings 'apple' and 'orange'.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter freque... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Special_variables | Special variables | Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| #Tcl | Tcl | # contains arguments passed to the ursa
# interpreter on the command line
string<> args
# iodevice that points to the console by default
iodevice console
# contains "\n"
string endl
# represents false
boolean false
# represents true
boolean true | Give a code snippet in #Tcl
Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/The_Name_Game | The Name Game | Write a program that accepts a name as input and outputs the lyrics to the Shirley Ellis song "The Name Game".
The regular verse
Unless your name begins with a vowel (A, E, I, O, U), 'B', 'F' or 'M' you don't have to care about special rules.
The verse for the name 'Gary' would be like this:
Gary, Gary, bo-bary... | #FreeBASIC | FreeBASIC | Sub TheGameName(nombre As String)
Dim As String x = Lcase(nombre)
x = Ucase(Mid(x,1,1)) + (Mid(x,2,Len(x)-1))
Dim As String x0 = Ucase(Mid(x,1,1))
Dim As String y
If x0 = "A" Or x0 = "E" Or x0 = "I" Or x0 = "O" Or x0 = "U" Then
y = Lcase(x)
Else
y = Mid(x,2)
End If
Di... | Give a code snippet in #FreeBASIC
Write a program that accepts a name as input and outputs the lyrics to the Shirley Ellis song "The Name Game".
The regular verse
Unless your name begins with a vowel (A, E, I, O, U), 'B', 'F' or 'M' you don't have to care about special rules.
The verse for the name 'Gary' would be... | 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:
*
* *
* *
* * * *
* *
* * * *
... | #ACL2 | ACL2 | (defun pascal-row (prev)
(if (endp (rest prev))
(list 1)
(cons (+ (first prev) (second prev))
(pascal-row (rest prev)))))
(defun pascal-triangle-r (rows prev)
(if (zp rows)
nil
(let ((curr (cons 1 (pascal-row prev))))
(cons curr (pascal-triangle-r (1- rows) cur... | Give a code snippet in #ACL2
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/Parsing/RPN_calculator_algorithm | Parsing/RPN calculator algorithm | Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the RPN expression generated from the... | #ooRexx | ooRexx | /* ooRexx *************************************************************
* 10.11.2012 Walter Pachl translated from PL/I via REXX
**********************************************************************/
fid='rpl.txt'
ex=linein(fid)
Say 'Input:' ex
/* ex=' 3 4 2 * 1 5 - 2 3 ^ ^ / +' */
Numeric Digits 15
expr=''
st=.circul... | Give a code snippet in #ooRexx
Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the R... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_prepend | String prepend |
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 |... | #Julia | Julia | s = "world!"
s = "Hello " * s | Give a code snippet in #Julia
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/Generator/Exponential | Generator/Exponential | A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so that the internal state of the objec... | #ALGOL_68 | ALGOL 68 | MODE YIELDVALUE = PROC(VALUE)VOID;
MODE GENVALUE = PROC(YIELDVALUE)VOID;
PROC gen filtered = (GENVALUE gen candidate, gen exclude, YIELDVALUE yield)VOID: (
VALUE candidate; SEMA have next exclude = LEVEL 0;
VALUE exclude; SEMA get next exclude = LEVEL 0;
BOOL initialise exclude := TRUE;
PAR ( # r... | Give a code snippet in #ALGOL_68
A generator is an executable entity (like a function or procedure) that contains code that yields a sequence of values, one at a time, so that each time you call the generator, the next value in the sequence is provided.
Generators are often built on top of coroutines or objects so th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Go | Go | package main
import "fmt"
func main() {
list := pancake{31, 41, 59, 26, 53, 58, 97, 93, 23, 84}
fmt.Println("unsorted:", list)
list.sort()
fmt.Println("sorted! ", list)
}
type pancake []int
func (a pancake) sort() {
for uns := len(a) - 1; uns > 0; uns-- {
// find largest in unsort... | Give a code snippet in #Go
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/Sorting_algorithms/Radix_sort | Sorting algorithms/Radix 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
... | #J | J |
radixSortR =: 3 : 0 NB. base radixSort data
16 radixSortR y
:
keys =. x #.^:_1 y NB. compute keys
length =. #{.keys
extra =. (-length) {."0 buckets =. i.x
for_pass. i.-length do.
keys =. ; (buckets,pass{"1 keys) <@:}./.extra,keys
end.
x#.keys NB. restore the data
) | Give a code snippet in #J
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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)
... | #FBSL | FBSL | #APPTYPE CONSOLE
DIM numbers AS STRING
DIM imod5 AS INTEGER
DIM imod3 AS INTEGER
FOR DIM i = 1 TO 100
numbers = ""
imod3 = i MOD 3
imod5 = i MOD 5
IF NOT imod3 THEN numbers = "Fizz"
IF NOT imod5 THEN numbers = numbers & "Buzz"
IF imod3 AND imod5 THEN numbers = i
PRINT numbers, " ";
NEXT
... | Give a code snippet in #FBSL
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/K-means%2B%2B_clustering | K-means++ clustering | K-means++ clustering
K-means
This data was partitioned into 7 clusters using the K-means algorithm.
The task is to implement the K-means++ algorithm. Produce a function which takes two arguments: the number of clusters K, and the dataset to classify. K is a positive integer and the dataset is a list of points in the C... | #Nim | Nim | #
# compile:
# nim c -d:release kmeans.nim
#
# and pipe the resultant EPS output to a file, e.g.
#
# kmeans > results.eps
#
import random, math, strutils
const
FloatMax = 1.0e100
nPoints = 100_000
nClusters = 11
type
Point = object
x, y: float
group: int
Points = seq[Point]
ClusterDist =... | Give a code snippet in #Nim
K-means++ clustering
K-means
This data was partitioned into 7 clusters using the K-means algorithm.
The task is to implement the K-means++ algorithm. Produce a function which takes two arguments: the number of clusters K, and the dataset to classify. K is a positive integer and the dataset... | 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)
... | #Visual_Prolog | Visual Prolog |
implement main
open core, console
class predicates
fizzbuzz : (integer) -> string procedure (i).
clauses
fizzbuzz(X) = S :- X mod 15 = 0, S = "FizzBuzz", !.
fizzbuzz(X) = S :- X mod 5 = 0, S = "Buzz", !.
fizzbuzz(X) = S :- X mod 3 = 0, S = "Fizz", !.
fizzbuzz(X) = S :- S = toString(X).
... | Give a code snippet in #Visual_Prolog
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perlin_noise | Perlin noise | The Perlin noise is a kind of gradient noise invented by Ken Perlin around the end of the twentieth century and still currently heavily used in computer graphics, most notably to procedurally generate textures or heightmaps.
The Perlin noise is basically a pseudo-random mapping of
R
d
... | #Perl | Perl | use strict;
use warnings;
use experimental 'signatures';
use constant permutation => qw{
151 160 137 91 90 15 131 13 201 95 96 53 194 233 7 225 140 36 103 30 69
142 8 99 37 240 21 10 23 190 6 148 247 120 234 75 0 26 197 62 94 252
219 203 117 35 11 32 57 177 33 88 237 149 56 87 17... | Give a code snippet in #Perl
The Perlin noise is a kind of gradient noise invented by Ken Perlin around the end of the twentieth century and still currently heavily used in computer graphics, most notably to procedurally generate textures or heightmaps.
The Perlin noise is basically a pseudo-random ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Password_generator | Password generator | Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-./:;<=>?@[]^_{|}~
(the above ch... | #Racket | Racket |
#lang racket
(require racket/cmdline)
(define valid-uppercase '(#\A #\B #\C #\D #\E #\F #\G #\H #\I #\J
#\K #\L #\M #\N #\O #\P #\Q #\R #\S #\T
#\U #\V #\W #\X #\Y #\Z))
(define valid-lowercase '(#\a #\b #\c #\d #\e #\f #\g #\h #\i #\j
... | Give a code snippet in #Racket
Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Closest-pair_problem | Closest-pair problem |
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Provide a function to find the closest two p... | #Delphi | Delphi | defmodule Closest_pair do
# brute-force algorithm:
def bruteForce([p0,p1|_] = points), do: bf_loop(points, {distance(p0, p1), {p0, p1}})
defp bf_loop([_], acc), do: acc
defp bf_loop([h|t], acc), do: bf_loop(t, bf_loop(h, t, acc))
defp bf_loop(_, [], acc), do: acc
defp bf_loop(p0, [p1|t], {minD, minP}) d... | Give a code snippet in #Delphi
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Provide a fu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Middle_three_digits | Middle three digits | Task
Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible.
Note: The order of the middle digits should be preserved.
Your function should be tested with the following values;... | #AWK | AWK | #!/bin/awk -f
# use as: awk -f middle_three_digits.awk
BEGIN {
n = split("123 12345 1234567 987654321 10001 -10001 -123 -100 100 -12345 1 2 -1 -10 2002 -2002 0", arr)
for (i=1; i<=n; i++) {
if (arr[i] !~ /^-?[0-9]+$/) {
printf("%10s : invalid input: not a number\n", arr[i])
continue
}
num = arr[i]<0... | Give a code snippet in #AWK
Task
Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible.
Note: The order of the middle digits should be preserved.
Your function should be test... | christopher/rosetta-code | |
http://rosettacode.org/wiki/ISBN13_check_digit | ISBN13 check digit | Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing:
978-1734314502 (good)
... | #Go | Go | package main
import (
"fmt"
"strings"
"unicode/utf8"
)
func checkIsbn13(isbn string) bool {
// remove any hyphens or spaces
isbn = strings.ReplaceAll(strings.ReplaceAll(isbn, "-", ""), " ", "")
// check length == 13
le := utf8.RuneCountInString(isbn)
if le != 13 {
return fals... | Give a code snippet in #Go
Task
Validate the check digit of an ISBN-13 code:
Multiply every other digit by 3.
Add these numbers and the other digits.
Take the remainder of this number after division by 10.
If it is 0, the ISBN-13 check digit is correct.
Use the following codes for testing:
978... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_unity | Roots of unity | The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| #Frink | Frink |
roots[n] :=
{
a = makeArray[[n], 0]
alpha = 360/n degrees
theta = 0 degrees
for k = 0 to length[a] - 1
{
a@k = cos[theta] + i sin[theta]
theta = theta + alpha
}
a
}
| Give a code snippet in #Frink
The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Include_a_file | Include a file | Task
Demonstrate the language's ability to include source code from other files.
See Also
Compiler/Simple file inclusion pre processor
| #Ring | Ring | Load 'file.ring' | Give a code snippet in #Ring
Task
Demonstrate the language's ability to include source code from other files.
See Also
Compiler/Simple file inclusion pre processor
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping | Tokenize a string with escaping | Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for splitting:
The fields that were s... | #Python | Python | def token_with_escape(a, escape = '^', separator = '|'):
'''
Issue python -m doctest thisfile.py to run the doctests.
>>> print(token_with_escape('one^|uno||three^^^^|four^^^|^cuatro|'))
['one|uno', '', 'three^^', 'four^|cuatro', '']
'''
result = []
token = ''
state = 0
... | Give a code snippet in #Python
Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for spl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #Visual_Basic_.NET | Visual Basic .NET | Module Module1
Sub Main()
Dim doors(100) As Boolean 'Door 1 is at index 0
For pass = 1 To 100
For door = pass - 1 To 99 Step pass
doors(door) = Not doors(door)
Next
Next
For door = 0 To 99
Console.WriteLine("Door # " & (door + 1) & " i... | Give a code snippet in #Visual_Basic_.NET
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2... | 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... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | {.checks: off, optimization: speed.} # Checks are deactivated and code is generated for speed.
# Define a type Color as pure which implies that value names are declared in their own scope
# and may/should be accessed with their type qualifier (as Color.Red).
type Color {.pure.} = enum Red, Green, Blue
# Declare ... | Give a code snippet in #Mathematica.2FWolfram_Language
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 la... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Newbie | Hello world/Newbie | Task
Guide a new user of a language through the steps necessary
to install the programming language and selection of a text editor if needed,
to run the languages' example in the Hello world/Text task.
Assume the language-newbie is a programmer in another language.
Assume the language-newbie is competent in install... | #REXX | REXX | /*REXX program to greet the world enthusiastically. */
say "Hello world!" | Give a code snippet in #REXX
Task
Guide a new user of a language through the steps necessary
to install the programming language and selection of a text editor if needed,
to run the languages' example in the Hello world/Text task.
Assume the language-newbie is a programmer in another language.
Assume the language-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zig-zag_matrix | Zig-zag matrix | Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to encode images).
For example, gi... | #REXX | REXX | /*REXX program produces and displays a zig─zag matrix (a square array). */
parse arg n start inc . /*obtain optional arguments from the CL*/
if n=='' | n=="," then n= 5 /*Not specified? Then use the default.*/
if start=='' | start=="," then start= 0 ... | Give a code snippet in #REXX
Task
Produce a zig-zag array.
A zig-zag array is a square arrangement of the first N2 natural numbers, where the
numbers increase sequentially as you zig-zag along the array's anti-diagonals.
For a graphical representation, see JPG zigzag (JPG uses such arrays to enco... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #Stata | Stata | program fib
args n
clear
qui set obs `n'
qui gen a=1
qui replace a=a[_n-1]+a[_n-2] in 3/l
end | Give a code snippet in #Stata
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Introspection | Introspection | Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop).
Extra credit
Repor... | #Maxima | Maxima | /* Get version information */
build_info();
/* build_info("5.27.0", "2012-05-08 11:27:57", "i686-pc-mingw32", "GNU Common Lisp (GCL)", "GCL 2.6.8") */
%@lisp_version;
/* "GCL 2.6.8" */
/* One can only check for user-defined objects: functions, variables, macros, ...
Hence we won't check for 'abs, which is built-... | Give a code snippet in #Maxima
Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute ab... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Law_of_cosines_-_triples | Law of cosines - triples | The Law of cosines states that for an angle γ, (gamma) of any triangle, if the sides adjacent to the angle are A and B and the side opposite is C; then the lengths of the sides are related by this formula:
A2 + B2 - 2ABcos(γ) = C2
Specific angles
For an angle of of 90º this becomes the more familiar ... | #Fortran | Fortran | MODULE LAW_OF_COSINES
IMPLICIT NONE
CONTAINS
! Calculate the third side of a triangle using the cosine rule
REAL FUNCTION COSINE_SIDE(SIDE_A, SIDE_B, ANGLE)
INTEGER, INTENT(IN) :: SIDE_A, SIDE_B
REAL(8), INTENT(IN) :: ANGLE
COSINE_SIDE = SIDE_A**2 + SIDE_B**2 - 2*SIDE_A*SID... | Give a code snippet in #Fortran
The Law of cosines states that for an angle γ, (gamma) of any triangle, if the sides adjacent to the angle are A and B and the side opposite is C; then the lengths of the sides are related by this formula:
A2 + B2 - 2ABcos(γ) = C2
Specific angles
For an angle of of 90º ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anti-primes | Anti-primes | The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI or android with termux */
/* program antiprime.s */
/* REMARK 1 : this program use routines in a include file
see task Include a file language arm assembly
for the routine affichageMess conversion10
see at end of this program the instruction include */
/* for constantes ... | Give a code snippet in #ARM_Assembly
The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| christopher/rosetta-code | |
http://rosettacode.org/wiki/P-value_correction | P-value correction | Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-values are sometimes called "q... | #C.23 | C# | using System;
using System.Collections.Generic;
using System.Linq;
namespace PValueCorrection {
class Program {
static List<int> SeqLen(int start, int end) {
var result = new List<int>();
if (start == end) {
for (int i = 0; i < end + 1; ++i) {
re... | Give a code snippet in #C.23
Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/State_name_puzzle | State name puzzle | Background
This task is inspired by Mark Nelson's DDJ Column "Wordplay" and one of the weekly puzzle challenges from Will Shortz on NPR Weekend Edition [1] and originally attributed to David Edelheit.
The challenge was to take the names of two U.S. States, mix them all together, then rearrange the letters to form the... | #Icon_and_Unicon | Icon and Unicon | link strings # for csort and deletec
procedure main(arglist)
ECsolve(S1 := getStates()) # original state names puzzle
ECsolve(S2 := getStates2()) # modified fictious names puzzle
GNsolve(S1)
GNsolve(S2)
end
procedure ECsolve(S) # Solve challenge using equivalence clas... | Give a code snippet in #Icon_and_Unicon
Background
This task is inspired by Mark Nelson's DDJ Column "Wordplay" and one of the weekly puzzle challenges from Will Shortz on NPR Weekend Edition [1] and originally attributed to David Edelheit.
The challenge was to take the names of two U.S. States, mix them all togethe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/K-means%2B%2B_clustering | K-means++ clustering | K-means++ clustering
K-means
This data was partitioned into 7 clusters using the K-means algorithm.
The task is to implement the K-means++ algorithm. Produce a function which takes two arguments: the number of clusters K, and the dataset to classify. K is a positive integer and the dataset is a list of points in the C... | #Racket | Racket |
#lang racket
(require racket/dict
math/distributions)
;; Divides the set of points into k clusters
;; using the standard k-means clustering algorithm
(define (k-means data k #:initialization (init k-means++))
(define (iteration centroids)
(map centroid (clusterize data centroids)))
(fixed-poin... | Give a code snippet in #Racket
K-means++ clustering
K-means
This data was partitioned into 7 clusters using the K-means algorithm.
The task is to implement the K-means++ algorithm. Produce a function which takes two arguments: the number of clusters K, and the dataset to classify. K is a positive integer and the data... | christopher/rosetta-code |
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