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/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... | #MATLAB_.2F_Octave | MATLAB / Octave | n = 15;
p = pascal(n + 2);
p(n + 4 : n + 3 : end - 1)' - diag(p, 2) | Give a code snippet in #MATLAB_.2F_Octave
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 Triang... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_common_divisor | Greatest common divisor | Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest common measure.
Related tas... | #Tcl | Tcl | package require Tcl 8.5
namespace path {::tcl::mathop ::tcl::mathfunc}
proc gcd_iter {p q} {
while {$q != 0} {
lassign [list $q [% $p $q]] p q
}
abs $p
} | Give a code snippet in #Tcl
Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #Delphi | Delphi | Type
pOneWayList = ^OneWayList;
OneWayList = record
pData : pointer ;
Next : pOneWayList ;
end; | Give a code snippet in #Delphi
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element de... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Output | Non-decimal radices/Output | Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routines of your programming langu... | #Nim | Nim | import strutils
for i in 0..33:
echo toBin(i, 6)," ",toOct(i, 3)," ",align($i,2)," ",toHex(i,2) | Give a code snippet in #Nim
Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Break | Loops/Break | Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If the number 10 is never gener... | #VBA | VBA | Public Sub LoopsBreak()
Dim value As Integer
Randomize
Do While True
value = Int(20 * Rnd)
Debug.Print value
If value = 10 Then Exit Do
Debug.Print Int(20 * Rnd)
Loop
End Sub | Give a code snippet in #VBA
Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-continuous_subsequences | Non-continuous subsequences | Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.)
A subsequence contains some subset of the elements of this sequence, in the same order.
A continuous subsequence is one in which no elements are missing between the first and last elements of the subseque... | #Wren | Wren | import "/fmt" for Fmt
var ncs = Fn.new { |a|
var f = "$d "
if (a[0] is String) {
for (i in 0...a.count) a[i] = a[i].bytes[0]
f = "$c "
}
var generate // recursive
generate = Fn.new { |m, k, c|
if (k == m) {
if (c[m - 1] != c[0] + m - 1) {
for (i ... | Give a code snippet in #Wren
Consider some sequence of elements. (It differs from a mere set of elements by having an ordering among members.)
A subsequence contains some subset of the elements of this sequence, in the same order.
A continuous subsequence is one in which no elements are missing between the first and... | 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... | #NewLISP | NewLISP | (dup "ha" 5) | Give a code snippet in #NewLISP
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/CSV_data_manipulation | CSV data manipulation | CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file, change some values and save the cha... | #Lua | Lua | local csv={}
for line in io.lines('file.csv') do
table.insert(csv, {})
local i=1
for j=1,#line do
if line:sub(j,j) == ',' then
table.insert(csv[#csv], line:sub(i,j-1))
i=j+1
end
end
table.insert(csv[#csv], line:sub(i,j))
end
table.insert(csv[1], 'SUM')
for i... | Give a code snippet in #Lua
CSV spreadsheet files are suitable for storing tabular data in a relatively portable way.
The CSV format is flexible but somewhat ill-defined.
For present purposes, authors may assume that the data fields contain no commas, backslashes, or quotation marks.
Task
Read a CSV file, change... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Window_creation/X11 | Window creation/X11 | Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| #PicoLisp | PicoLisp | #!/usr/bin/picolisp /usr/lib/picolisp/lib.l
(load "@lib/misc.l" "@lib/gcc.l")
(gcc "x11" '("-lX11") 'simpleWin)
#include <X11/Xlib.h>
any simpleWin(any ex) {
any x = cdr(ex);
int dx, dy;
Display *disp;
int scrn;
Window win;
XEvent ev;
x = cdr(ex), dx = (int)evCnt(ex,x);
x = cdr(x), d... | Give a code snippet in #PicoLisp
Task
Create a simple X11 application, using an X11 protocol library such as Xlib or XCB, that draws a box and "Hello World" in a window.
Implementations of this task should avoid using a toolkit as much as possible.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep 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
... | #Groovy | Groovy |
@Grab(group = 'org.codehaus.gpars', module = 'gpars', version = '1.2.1')
import groovyx.gpars.GParsPool
GParsPool.withPool args.size(), {
args.eachParallel {
sleep(it.toInteger() * 10)
println it
}
}
| Give a code snippet in #Groovy
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/Mian-Chowla_sequence | Mian-Chowla sequence | The Mian–Chowla sequence is an integer sequence defined recursively.
Mian–Chowla is an infinite instance of a Sidon sequence, and belongs to the class known as B₂ sequences.
The sequence starts with:
a1 = 1
then for n > 1, an is the smallest positive integer such that every pairwise sum
ai + aj
is distinct, fo... | #Java | Java |
import java.util.Arrays;
public class MianChowlaSequence {
public static void main(String[] args) {
long start = System.currentTimeMillis();
System.out.println("First 30 terms of the Mian–Chowla sequence.");
mianChowla(1, 30);
System.out.println("Terms 91 through 100 of the Mia... | Give a code snippet in #Java
The Mian–Chowla sequence is an integer sequence defined recursively.
Mian–Chowla is an infinite instance of a Sidon sequence, and belongs to the class known as B₂ sequences.
The sequence starts with:
a1 = 1
then for n > 1, an is the smallest positive integer such that every pairwise... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Horizontal_sundial_calculations | Horizontal sundial calculations | Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit... | #BASIC | BASIC |
10 REM Horizontal sundial calculations
20 DEF FNM(X) = INT(X*1000+0.5)/1000
30 PRINT "Enter latitude";
40 INPUT L
50 PRINT "Enter longitude";
60 INPUT L1
70 PRINT "Enter legal meridian";
80 INPUT R
90 PRINT
100 LET P = 4*ATN(1)
110 LET S1 = SIN(L*P/180)
120 PRINT " sine of latitude:"; S1
130 PRINT " diff longit... | Give a code snippet in #BASIC
Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island... | 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 ... | #Latitude | Latitude | arr := n times to (Array) map { Object clone. }. | Give a code snippet in #Latitude
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 consi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Time_a_function | Time a function | Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
between start and finish, which could ... | #Clojure | Clojure |
(defn fib []
(map first
(iterate
(fn [[a b]] [b (+ a b)])
[0 1])))
(time (take 100 (fib)))
| Give a code snippet in #Clojure
Task
Write a program which uses a timer (with the least granularity available
on your system) to time how long a function takes to execute.
Whenever possible, use methods which measure only the processing time used
by the current process; instead of the difference in system time
betwe... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/RPN_to_infix_conversion | Parsing/RPN to infix conversion | Parsing/RPN to infix conversion
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a program that takes an RPN representation of an expression formatted as a space separated sequence of tokens and generates the equivalent expression in infix notation.... | #Visual_Basic_.NET | Visual Basic .NET | Option Strict On
Imports System.Text.RegularExpressions
Module Module1
Class Operator_
Sub New(t As Char, p As Integer, Optional i As Boolean = False)
Token = t
Precedence = p
IsRightAssociative = i
End Sub
Property Token As Char
Get
... | Give a code snippet in #Visual_Basic_.NET
Parsing/RPN to infix conversion
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a program that takes an RPN representation of an expression formatted as a space separated sequence of tokens and generates t... | 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.
| #AWK | AWK | BEGIN {
s="/inet/tcp/256/0/0"
print strftime() |& s
close(s)
}
| Give a code snippet in #AWK
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/Factorions | Factorions |
Definition
A factorion is a natural number that equals the sum of the factorials of its digits.
Example
145 is a factorion in base 10 because:
1! + 4! + 5! = 1 + 24 + 120 = 145
It can be shown (see talk page) that no factorion in base 10 can exceed 1,499,999.
Task
Write a progr... | #Haskell | Haskell | import Text.Printf (printf)
import Data.List (unfoldr)
import Control.Monad (guard)
factorion :: Int -> Int -> Bool
factorion b n = f b n == n
where
f b = sum . map (product . enumFromTo 1) . unfoldr (\x -> guard (x > 0) >> pure (x `mod` b, x `div` b))
main :: IO ()
main = mapM_ (uncurry (printf "Factorions for ... | Give a code snippet in #Haskell
Definition
A factorion is a natural number that equals the sum of the factorials of its digits.
Example
145 is a factorion in base 10 because:
1! + 4! + 5! = 1 + 24 + 120 = 145
It can be shown (see talk page) that no factorion in base 10 can exceed ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pseudo-random_numbers/Splitmix64 | Pseudo-random numbers/Splitmix64 | Splitmix64 is the default pseudo-random number generator algorithm in Java and is included / available in many other languages. It uses a fairly simple algorithm that, though it is considered to be poor for cryptographic purposes, is very fast to calculate, and is "good enough" for many random number needs. It passes s... | #Go | Go | package main
import (
"fmt"
"math"
)
type Splitmix64 struct{ state uint64 }
func Splitmix64New(state uint64) *Splitmix64 { return &Splitmix64{state} }
func (sm64 *Splitmix64) nextInt() uint64 {
sm64.state += 0x9e3779b97f4a7c15
z := sm64.state
z = (z ^ (z >> 30)) * 0xbf58476d1ce4e5b9
z = ... | Give a code snippet in #Go
Splitmix64 is the default pseudo-random number generator algorithm in Java and is included / available in many other languages. It uses a fairly simple algorithm that, though it is considered to be poor for cryptographic purposes, is very fast to calculate, and is "good enough" for many rand... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gamma_function | Gamma function | Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function.
The Gamma funct... | #Sidef | Sidef | var a = [ 1.00000_00000_00000_00000, 0.57721_56649_01532_86061, -0.65587_80715_20253_88108,
-0.04200_26350_34095_23553, 0.16653_86113_82291_48950, -0.04219_77345_55544_33675,
-0.00962_19715_27876_97356, 0.00721_89432_46663_09954, -0.00116_51675_91859_06511,
-0.00021_52416_74114_95097, 0.0... | Give a code snippet in #Sidef
Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/lib... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_a_list_of_object_identifiers | Sort a list of object identifiers |
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
... | #Nim | Nim | import algorithm, sequtils, strutils
type OID = distinct string
# Borrow the `$` procedure from the base string type.
proc `$`(oid: OID): string {.borrow.}
template toSeqInt(oid: OID): seq[int] =
## Convert an OID into a sequence of integers.
oid.string.split('.').map(parseInt)
proc oidCmp(a, b: OID): i... | Give a code snippet in #Nim
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/Repeat | Repeat | Task
Write a procedure which accepts as arguments another procedure and a positive integer.
The latter procedure is executed a number of times equal to the accepted integer.
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Sub proc()
Print " proc called"
End Sub
Sub repeat(s As Sub, n As UInteger)
For i As Integer = 1 To n
Print Using "##"; i;
s()
Next
End Sub
repeat(@proc, 5)
Print
Print "Press any key to quit"
Sleep | Give a code snippet in #FreeBASIC
Task
Write a procedure which accepts as arguments another procedure and a positive integer.
The latter procedure is executed a number of times equal to the accepted integer.
| 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.
| #ML.2FI | ML/I | MCSKIP "WITH" NL
"" Special variables
"" There are four different kinds of variables in ML/I.
"" Permanent (P) variables - these have no special predefined values.
"" Character (C) variables - these have no special predefined values.
"" Temporary (T) variables - a macro has at least three of these, and
"" those have... | Give a code snippet in #ML.2FI
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/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 ... | #Racket | Racket | #lang racket
;;; reads a licence file on standard input
;;; returns max licences used and list of times this occurred
(define (count-licences)
(let inner ((ln (read-line)) (in-use 0) (max-in-use 0) (times-list null))
(if (eof-object? ln)
(values max-in-use (reverse times-list))
(let ((mtch (regex... | Give a code snippet in #Racket
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 ch... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pseudo-random_numbers/Splitmix64 | Pseudo-random numbers/Splitmix64 | Splitmix64 is the default pseudo-random number generator algorithm in Java and is included / available in many other languages. It uses a fairly simple algorithm that, though it is considered to be poor for cryptographic purposes, is very fast to calculate, and is "good enough" for many random number needs. It passes s... | #Factor | Factor | USING: io kernel math math.bitwise math.functions
math.statistics namespaces prettyprint sequences ;
SYMBOL: state
: seed ( n -- ) 64 bits state set ;
: next-int ( -- n )
0x9e3779b97f4a7c15 state [ + 64 bits ] change
state get -30 0xbf58476d1ce4e5b9 -27 0x94d049bb133111eb -31 1
[ [ dupd shift bitxor ]... | Give a code snippet in #Factor
Splitmix64 is the default pseudo-random number generator algorithm in Java and is included / available in many other languages. It uses a fairly simple algorithm that, though it is considered to be poor for cryptographic purposes, is very fast to calculate, and is "good enough" for many ... | 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.
| #Pascal | Pascal | Program Sockets_ExampleA;
Uses
{ Free Pascal RTL sockets unit }
sockets;
Var
TCP_Sock: integer;
Remote_Addr: TSockAddr;
Message: string;
PMessage: Pchar;
Message_Len: integer;
Begin
{ Fill the record (struct) with the server's address information }
With Remote_Addr do
begin
S... | Give a code snippet in #Pascal
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/Fusc_sequence | Fusc sequence |
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition starts with unity, not zero. Th... | #Ruby | Ruby | fusc = Enumerator.new do |y|
y << 0
y << 1
arr = [0,1]
2.step do |n|
res = n.even? ? arr[n/2] : arr[(n-1)/2] + arr[(n+1)/2]
y << res
arr << res
end
end
fusc_max_digits = Enumerator.new do |y|
cur_max, cur_exp = 0, 0
0.step do |i|
f = fusc.next
if f >= cur_max
cur_exp ... | Give a code snippet in #Ruby
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition sta... | 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,... | #PicoLisp | PicoLisp | (setq A '((1 2 3) (a b c) ((d e) NIL 777))) # Create a 3x3 structure
(mapc println A) # Show it | Give a code snippet in #PicoLisp
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 re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_reversal_game | Number reversal game | Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score is the count of the reversa... | #R | R | reversalGame <- function(){
cat("Welcome to the Number Reversal Game! \n")
cat("Sort the numbers into ascending order by repeatedly \n",
"reversing the first n digits, where you specify n. \n \n", sep="")
# Generate a list that's definitely not in ascending order, per instuctions
data <- sample(1:9, 9)
... | Give a code snippet in #R
Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sutherland-Hodgman_polygon_clipping | Sutherland-Hodgman polygon clipping | The Sutherland-Hodgman clipping algorithm finds the polygon that is the intersection between an arbitrary polygon (the “subject polygon”) and a convex polygon (the “clip polygon”).
It is used in computer graphics (especially 2D graphics) to reduce the complexity of a scene being displayed by eliminating parts of a... | #Phix | Phix | --
-- demo\rosetta\Sutherland_Hodgman_polygon_clipping.exw
-- ====================================================
--
with javascript_semantics
enum X,Y
function inside(sequence cp1, cp2, p)
return (cp2[X]-cp1[X])*(p[Y]-cp1[Y])>(cp2[Y]-cp1[Y])*(p[X]-cp1[X])
end function
function intersect(sequence cp1, cp2, s, e)... | Give a code snippet in #Phix
The Sutherland-Hodgman clipping algorithm finds the polygon that is the intersection between an arbitrary polygon (the “subject polygon”) and a convex polygon (the “clip polygon”).
It is used in computer graphics (especially 2D graphics) to reduce the complexity of a scene being displ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Shoelace_formula_for_polygonal_area | Shoelace formula for polygonal area | Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs returns the absolute value)
Task
Write ... | #Maple | Maple |
with(ArrayTools):
module Point()
option object;
local x := 0;
local y := 0;
export getX::static := proc(self::Point, $)
return self:-x;
end proc;
export getY::static := proc(self::Point, $)
return self:-y
end proc;
export ModuleApply::static := proc()
Object(Point, _passed);
end proc;
export... | Give a code snippet in #Maple
Given the n + 1 vertices x[0], y[0] .. x[N], y[N] of a simple polygon described in a clockwise direction, then the polygon's area can be calculated by:
abs( (sum(x[0]*y[1] + ... x[n-1]*y[n]) + x[N]*y[0]) -
(sum(x[1]*y[0] + ... x[n]*y[n-1]) + x[0]*y[N])
) / 2
(Where abs returns th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_a_system_command | Execute a system command | Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| #Visual_Basic_.NET | Visual Basic .NET | Module System_Command
Sub Main()
Dim cmd As New Process
cmd.StartInfo.FileName = "cmd.exe"
cmd.StartInfo.RedirectStandardInput = True
cmd.StartInfo.RedirectStandardOutput = True
cmd.StartInfo.CreateNoWindow = True
cmd.StartInfo.UseShellExecute = False
cmd.... | Give a code snippet in #Visual_Basic_.NET
Task
Run either the ls system command (dir on Windows), or the pause system command.
Related task
Get system command output
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Element-wise_operations | Element-wise operations | This task is similar to:
Matrix multiplication
Matrix transposition
Task
Implement basic element-wise matrix-matrix and scalar-matrix operations, which can be referred to in other, higher-order tasks.
Implement:
addition
subtraction
multiplication
division
exponentiation
Extend the task if ... | #PicoLisp | PicoLisp | (de elementWiseMatrix (Fun Mat1 Mat2)
(mapcar '((L1 L2) (mapcar Fun L1 L2)) Mat1 Mat2) )
(de elementWiseScalar (Fun Mat Scalar)
(elementWiseMatrix Fun Mat (circ (circ Scalar))) ) | Give a code snippet in #PicoLisp
This task is similar to:
Matrix multiplication
Matrix transposition
Task
Implement basic element-wise matrix-matrix and scalar-matrix operations, which can be referred to in other, higher-order tasks.
Implement:
addition
subtraction
multiplication
division
ex... | 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... | #AutoIt | AutoIt |
ConsoleWrite(Fibonacci(10) & @CRLF) ; ## USAGE EXAMPLE
ConsoleWrite(Fibonacci(20) & @CRLF) ; ## USAGE EXAMPLE
ConsoleWrite(Fibonacci(30)) ; ## USAGE EXAMPLE
Func Fibonacci($number)
If $number < 0 Then Return "Invalid argument" ; No negative numbers
If $number < 2 Then ; If $n... | Give a code snippet in #AutoIt
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 unwan... | 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:
*
* *
* *
* * * *
* *
* * * *
... | #Pascal | Pascal | program Sierpinski;
function ipow(b, n : Integer) : Integer;
var
i : Integer;
begin
ipow := 1;
for i := 1 to n do
ipow := ipow * b
end;
function truth(a : Char) : Boolean;
begin
if a = '*' then
truth := true
else
truth := false
end; | Give a code snippet in #Pascal
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/Largest_int_from_concatenated_ints | Largest int from concatenated ints | Task
Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer.
Use the following two sets of integers as tests and show your program output here.
{1, 34, 3, 98, 9, 76, 45, 4}
{54,... | #Elixir | Elixir | defmodule RC do
def largest_int(list) do
sorted = Enum.sort(list, fn x,y -> "#{x}#{y}" >= "#{y}#{x}" end)
Enum.join(sorted)
end
end
IO.inspect RC.largest_int [1, 34, 3, 98, 9, 76, 45, 4]
IO.inspect RC.largest_int [54, 546, 548, 60] | Give a code snippet in #Elixir
Task
Given a set of positive integers, write a function to order the integers in such a way that the concatenation of the numbers forms the largest possible integer and return this integer.
Use the following two sets of integers as tests and show your program output here.
{1, ... | 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
| #Programming_Language | Programming Language | print(Hello world!) | Give a code snippet in #Programming_Language
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/S... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would repr... | #BBC_BASIC | BBC BASIC | DIM a(2), b(2), c(2), d(2)
a() = 3, 4, 5
b() = 4, 3, 5
c() = -5, -12, -13
PRINT "a . b = "; FNdot(a(),b())
PROCcross(a(),b(),d())
PRINT "a x b = (";d(0)", ";d(1)", ";d(2)")"
PRINT "a . (b x c) = "; FNscalartriple(a(),b(),c())
PROCvectortriple(a(),b(),c(),d())
... | Give a code snippet in #BBC_BASIC
A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Metronome | Metronome |
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for production of the beat notes, and an ext... | #Ruby | Ruby |
#!/usr/bin/ruby
bpm = Integer(ARGV[0]) rescue 60 # sets BPM by the first command line argument, set to 60 if none provided
msr = Integer(ARGV[1]) rescue 4 # sets number of beats in a measure by the second command line argument, set to 4 if none provided
i = 0
loop do
(msr-1).times do
puts "\a"
sleep(60... | Give a code snippet in #Ruby
The task is to implement a metronome.
The metronome should be capable of producing high and low audio beats, accompanied by a visual beat indicator, and the beat pattern and tempo should be configurable.
For the purpose of this task, it is acceptable to play sound files for production... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Address_of_a_variable | Address of a variable |
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 |... | #Creative_Basic | Creative Basic |
== Get ==
To get the address of a variable without using the Windows API:
DEF X:INT
DEF pPointer:POINTER
pPointer=X
----
To get the address of a variable using the Windows API Lstrcpy function called in Creative Basic:
(This may give users of another language without a native way to get the address of a varia... | Give a code snippet in #Creative_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 Op... | 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... | #Ruby | Ruby | $cache = {}
def selfReferentialSequence_cached(n, seen = [])
return $cache[n] if $cache.include? n
return [] if seen.include? n
digit_count = Array.new(10, 0)
n.to_s.chars.collect {|char| digit_count[char.to_i] += 1}
term = ''
9.downto(0).each do |d|
if digit_count[d] > 0
term += digit_count[d].... | Give a code snippet in #Ruby
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, 31131... | christopher/rosetta-code | |
http://rosettacode.org/wiki/15_puzzle_game | 15 puzzle game |
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| #Racket | Racket | #lang racket/base
(require 2htdp/universe 2htdp/image racket/list racket/match)
(define ((fifteen->pict (finished? #f)) fifteen)
(for/fold ((i (empty-scene 0 0))) ((r 4))
(define row
(for/fold ((i (empty-scene 0 0))) ((c 4))
(define v (list-ref fifteen (+ (* r 4) c)))
(define cell
... | Give a code snippet in #Racket
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Concurrent_computing | Concurrent computing | Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
| #Java | Java | import java.util.concurrent.CyclicBarrier;
public class Threads
{
public static class DelayedMessagePrinter implements Runnable
{
private CyclicBarrier barrier;
private String msg;
public DelayedMessagePrinter(CyclicBarrier barrier, String msg)
{
this.barrier = barrier;
this.msg = ms... | Give a code snippet in #Java
Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your la... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Boolean_values | Boolean values | Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| #Ring | Ring |
x = True
y = False
see "x and y : " + (x and y) + nl
see "x or y : " + (x or y) + nl
see "not x : " + (not x) + nl
| Give a code snippet in #Ring
Task
Show how to represent the boolean states "true" and "false" in a language.
If other objects represent "true" or "false" in conditionals, note it.
Related tasks
Logical operations
| christopher/rosetta-code | |
http://rosettacode.org/wiki/General_FizzBuzz | General FizzBuzz | Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along with the corresponding word to be ... | #Rust | Rust | use std::io;
use std::io::BufRead;
fn parse_entry(l: &str) -> (i32, String) {
let params: Vec<&str> = l.split(' ').collect();
let divisor = params[0].parse::<i32>().unwrap();
let word = params[1].to_string();
(divisor, word)
}
fn main() {
let stdin = io::stdin();
let mut lines = stdin.lock... | Give a code snippet in #Rust
Task
Write a generalized version of FizzBuzz that works for any list of factors, along with their words.
This is basically a "fizzbuzz" implementation where the user supplies the parameters.
The user will enter the max number, then they will enter the factors to be calculated along with... | 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 ... | #NS-HUBASIC | NS-HUBASIC | 10 LIST | Give a code snippet in #NS-HUBASIC
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 progr... | 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
| #Ruby | Ruby | str = "I am a string"
p "Ends with 'string'" if str =~ /string$/
p "Does not start with 'You'" unless str =~ /^You/ | Give a code snippet in #Ruby
Task
match a string against a regular expression
substitute part of a string using a regular expression
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Generate_lower_case_ASCII_alphabet | Generate lower case ASCII alphabet | Task
Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence.
For this basic task use a reliable style of coding, a sty... | #Prolog | Prolog | a_to_z(From, To, L) :-
maplist(atom_codes, [From, To], [[C_From], [C_To]]),
bagof([C], between(C_From, C_To, C), L1),
maplist(atom_codes,L, L1).
| Give a code snippet in #Prolog
Task
Generate an array, list, lazy sequence, or even an indexable string of all the lower case ASCII characters, from a to z. If the standard library contains such a sequence, show how to access it, but don't fail to show how to generate a similar sequence.
For this basic task use a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Graphical | Hello world/Graphical |
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| #Visual_Basic_.NET | Visual Basic .NET | Imports System.Windows.Forms
Module GoodbyeWorld
Sub Main()
Messagebox.Show("Goodbye, World!")
End Sub
End Module | Give a code snippet in #Visual_Basic_.NET
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_multiplication | Long multiplication | Task
Explicitly implement long multiplication.
This is one possible approach to arbitrary-precision integer algebra.
For output, display the result of 264 * 264.
Optionally, verify your result against builtin arbitrary precision support.
The decimal representation of 264 is:
18,446,744,073,709,551,61... | #ALGOL_68 | ALGOL 68 | PRAGMAT precision=200 PRAGMAT
MODE INTEGER = LONG LONG INT;
LONG INT default integer width := 69;
INT width = 69+2;
INT fix w = 1, fix h = 1; # round up #
LONG LONG INT golden ratio w := ENTIER ((long long sqrt(5)-1) / 2 * LENG LENG 10 ** default integer width + fix w),
golden ratio h := ENTIER ((lo... | Give a code snippet in #ALGOL_68
Task
Explicitly implement long multiplication.
This is one possible approach to arbitrary-precision integer algebra.
For output, display the result of 264 * 264.
Optionally, verify your result against builtin arbitrary precision support.
The decimal representation of 264... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Pythagorean_means | Averages/Pythagorean means | Task[edit]
Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive).
Show that
A
(
x
1
,
…
,
x
n
)
≥
G
(
x
1
,
…
,
x
n
)
≥
H
(
x
1
,
…
,
x
n
)
{\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{1},\ldots ,x_{n})}
for this set of p... | #C | C | #include <stdio.h>
#include <stdlib.h> // atoi()
#include <math.h> // pow()
int main(int argc, char* argv[])
{
int i, count=0;
double f, sum=0.0, prod=1.0, resum=0.0;
for (i=1; i<argc; ++i) {
f = atof(argv[i]);
count++;
sum += f;
prod *= f;
resum += (1.0/f);
}
//printf(" c:%d\n s:%f\n ... | Give a code snippet in #C
Task[edit]
Compute all three of the Pythagorean means of the set of integers 1 through 10 (inclusive).
Show that
A
(
x
1
,
…
,
x
n
)
≥
G
(
x
1
,
…
,
x
n
)
≥
H
(
x
1
,
…
,
x
n
)
{\displaystyle A(x_{1},\ldots ,x_{n})\geq G(x_{1},\ldots ,x_{n})\geq H(x_{1},\ldots ,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Raku | Raku | Give a code snippet in #Raku
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Cumulative_standard_deviation | Cumulative standard deviation | Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function in the implementation langu... | #J | J | mean=: +/ % #
dev=: - mean
stddevP=: [: %:@mean *:@dev NB. A) 3 equivalent defs for stddevP
stddevP=: [: mean&.:*: dev NB. B) uses Under (&.:) to apply inverse of *: after mean
stddevP=: %:@(mean@:*: - *:@mean) NB. C) sqrt of ((mean of squares) - (square of mean))
stddevP\ 2 ... | Give a code snippet in #J
Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/URL_parser | URL parser | URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
According to the standards, t... | #Rust | Rust | use url::Url;
fn print_fields(url: Url) -> () {
println!("scheme: {}", url.scheme());
println!("username: {}", url.username());
if let Some(password) = url.password() {
println!("password: {}", password);
}
if let Some(domain) = url.domain() {
println!("domain: {}", domain);
... | Give a code snippet in #Rust
URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop b... | #Stata | Stata | forvalues i=1(2)10 {
display "`i'"
}
1
3
5
7
9 | Give a code snippet in #Stata
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Inc... | 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
... | #M4 | M4 | define(`ack',`ifelse($1,0,`incr($2)',`ifelse($2,0,`ack(decr($1),1)',`ack(decr($1),ack($1,decr($2)))')')')dnl
ack(3,3) | Give a code snippet in #M4
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
... | 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... | #Delphi.2FPascal | Delphi/Pascal | var
matrix: array[1..10,1..10] of Integer;
row, col: Integer;
broken: Boolean;
begin
// Launch random number generator
randomize;
// Filling matrix with random numbers
for row := 1 to 10 do
for col := 1 to 10 do
matrix[row, col] := Succ(Random(20));
// Displaying values one by one, until at th... | Give a code snippet in #Delphi.2FPascal
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 2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_intersection_of_a_line_with_a_plane | Find the intersection of a line with a plane | Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of (0, 0, 1) and which passes ... | #Prolog | Prolog |
:- initialization(main).
vector_plus(U, V, W) :-
U = p(X1, Y1, Z1),
V = p(X2, Y2, Z2),
X3 is X1 + X2,
Y3 is Y1 + Y2,
Z3 is Z1 + Z2,
W = p(X3, Y3, Z3).
vector_minus(U, V, W) :-
U = p(X1, Y1, Z1),
V = p(X2, Y2, Z2),
X3 is X1 - X2,
Y3 is Y1 - Y2,
Z3 is Z1 - Z2,
W = p(X... | Give a code snippet in #Prolog
Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop b... | #Kotlin | Kotlin | // version 1.0.6
fun main(args: Array<String>) {
for (i in 1 .. 21 step 2) print("$i ")
} | Give a code snippet in #Kotlin
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/In... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Aliquot_sequence_classifications | Aliquot sequence classifications | An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications for non termination:
If the s... | #11l | 11l | F pdsum(n)
R sum((1 .. (n + 1) I/ 2).filter(x -> @n % x == 0 & @n != x))
F aliquot(n, maxlen = 16, maxterm = 2 ^ 30)
I n == 0
R (‘terminating’, [0])
V s = [n]
V slen = 1
V new = n
L slen <= maxlen & new < maxterm
new = pdsum(s.last)
I new C s
I s[0] == new
I sl... | Give a code snippet in #11l
An aliquot sequence of a positive integer K is defined recursively as the first member
being K and subsequent members being the sum of the Proper divisors of the previous term.
If the terms eventually reach 0 then the series for K is said to terminate.
There are several classifications f... | 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 |... | #Sparkling | Sparkling | let a = 13, b = 37;
if a < b {
print("a < b");
} else if a > b {
print("a > b");
} else if a == b {
print("a == b");
} else {
print("either a or b or both are NaN");
} | Give a code snippet in #Sparkling
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 Operati... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_a_series | Sum of a series | Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
k
=
1
n
1
k
2
{\displa... | #MiniScript | MiniScript | zeta = function(num)
return 1 / num^2
end function
sum = function(start, finish, formula)
total = 0
for i in range(start, finish)
total = total + formula(i)
end for
return total
end function
print sum(1, 1000, @zeta)
| Give a code snippet in #MiniScript
Compute the nth term of a series, i.e. the sum of the n first terms of the corresponding sequence.
Informally this value, or its limit when n tends to infinity, is also called the sum of the series, thus the title of this task.
For this task, use:
S
n
=
∑
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #HicEst | HicEst | OPEN(FIle= 'input.txt', OLD, IOStat=ios, ERror=99)
OPEN(FIle='C:\input.txt', OLD, IOStat=ios, ERror=99)
! ...
99 WRITE(Messagebox='!') 'File does not exist. Error message ', ios | Give a code snippet in #HicEst
Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works wi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_case | String case | Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not reversable.
Show any additional... | #Frink | Frink |
a = "alphaBETA"
println[lc[a]]
println[uc[a]]
| Give a code snippet in #Frink
Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_the_coins | Count the coins | There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels and 5 pennies
A nickel and 10 pen... | #IS-BASIC | IS-BASIC | 100 PROGRAM "Coins.bas"
110 LET MONEY=100
120 LET COUNT=0
125 PRINT "Count Pennies Nickles Dimes Quaters"
130 FOR QC=0 TO INT(MONEY/25)
150 FOR DC=0 TO INT((MONEY-QC*25)/10)
170 FOR NC=0 TO INT((MONEY-DC*10)/5)
190 FOR PC=0 TO MONEY-NC*5 STEP 5
200 LET S=PC+NC*5+DC*10+QC*25
210 IF S=MONEY T... | Give a code snippet in #IS-BASIC
There are four types of common coins in US currency:
quarters (25 cents)
dimes (10 cents)
nickels (5 cents), and
pennies (1 cent)
There are six ways to make change for 15 cents:
A dime and a nickel
A dime and 5 pennies
3 nickels
2 nickels an... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anagrams/Deranged_anagrams | Anagrams/Deranged anagrams | Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.
Task[edit]
Use the word list at uni... | #Ruby | Ruby | def deranged?(a, b)
a.chars.zip(b.chars).all? {|char_a, char_b| char_a != char_b}
end
def find_derangements(list)
list.combination(2) {|a,b| return a,b if deranged?(a,b)}
nil
end
require 'open-uri'
anagram = open('http://www.puzzlers.org/pub/wordlists/unixdict.txt') do |f|
f.read.split.group_by {|s| s.each... | Give a code snippet in #Ruby
Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.
Task[... | 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... | #LiveCode | LiveCode | command shaRosettaCode
local shex, sha1
put sha1Digest("Rosetta Code") into sha1
get binaryDecode("H*",sha1,shex)
put shex
end shaRosettaCode | Give a code snippet in #LiveCode
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Statistics/Normal_distribution | Statistics/Normal distribution | The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform random number generator and create a ... | #Nim | Nim | import math, random, sequtils, stats, strformat, strutils
proc drawHistogram(ns: seq[float]) =
# Distribute values in bins.
const NBins = 50
var minval = min(ns)
var maxval = max(ns)
var h = newSeq[int](NBins + 1)
for n in ns:
let pos = ((n - minval) * NBins / (maxval - minval)).toInt
inc h[pos]... | Give a code snippet in #Nim
The Normal (or Gaussian) distribution is a frequently used distribution in statistics. While most programming languages provide a uniformly distributed random number generator, one can derive normally distributed random numbers from a uniform generator.
The task
Take a uniform random n... | 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... | #LiveCode | LiveCode | function rlEncode str
local charCount
put 1 into charCount
repeat with i = 1 to the length of str
if char i of str = char (i + 1) of str then
add 1 to charCount
else
put char i of str & charCount after rle
put 1 into charCount
end if
end repeat... | Give a code snippet in #LiveCode
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 f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #Wortel | Wortel | @uniq [1 2 3 2 1 2 3] ; returns [1 2 3] | Give a code snippet in #Wortel
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/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... | #Python | Python | inclusive_range = mn, mx = (1, 10)
print('''\
Think of a number between %i and %i and wait for me to guess it.
On every guess of mine you should state whether the guess was
too high, too low, or equal to your number by typing h, l, or =
''' % inclusive_range)
i = 0
while True:
i += 1
guess = (mn+mx)//2
... | Give a code snippet in #Python
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/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #Bracmat | Bracmat | @("fesylk789/35768poq2art":? (#<7:?n & out$!n & ~) ?) | Give a code snippet in #Bracmat
Task
match a string against a regular expression
substitute part of a string using a regular expression
| 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... | #Elixir | Elixir | defmodule RC do
def entropy(str) do
leng = String.length(str)
String.graphemes(str)
|> Enum.group_by(&(&1))
|> Enum.map(fn{_,value} -> length(value) end)
|> Enum.reduce(0, fn count, entropy ->
freq = count / leng
entropy - freq * :math.log2(freq)
end)
end
end
IO.inspec... | Give a code snippet in #Elixir
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/Cyclotomic_polynomial | Cyclotomic polynomial | The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n.
Task
Find and print the first 30 cyclotomic polynomials.
Find and print the order of the first 10... | #C.2B.2B | C++ | #include <algorithm>
#include <iostream>
#include <initializer_list>
#include <map>
#include <vector>
const int MAX_ALL_FACTORS = 100000;
const int algorithm = 2;
int divisions = 0;
//Note: Cyclotomic Polynomials have small coefficients. Not appropriate for general polynomial usage.
class Term {
private:
long ... | Give a code snippet in #C.2B.2B
The nth Cyclotomic polynomial, for any positive integer n, is the unique irreducible polynomial of largest degree with integer coefficients that is a divisor of x^n − 1, and is not a divisor of x^k − 1 for any k < n.
Task
Find and print the first 30 cyclotomic polynomials.
Find an... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_missing_permutation | Find the missing permutation | ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
CDBA
... | #Groovy | Groovy | def fact = { n -> [1,(1..<(n+1)).inject(1) { prod, i -> prod * i }].max() }
def missingPerms
missingPerms = {List elts, List perms ->
perms.empty ? elts.permutations() : elts.collect { e ->
def ePerms = perms.findAll { e == it[0] }.collect { it[1..-1] }
ePerms.size() == fact(elts.size() - 1) ? [] \
... | Give a code snippet in #Groovy
ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/List_comprehensions | List comprehensions | A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and the use of map and filter functio... | #EchoLisp | EchoLisp |
;; copied from Racket
(for*/list ([x (in-range 1 21)]
[y (in-range x 21)]
[z (in-range y 21)])
#:when (= (+ (* x x) (* y y)) (* z z))
(list x y z))
→ ((3 4 5) (5 12 13) (6 8 10) (8 15 17) (9 12 15) (12 16 20))
| Give a code snippet in #EchoLisp
A list comprehension is a special syntax in some programming languages to describe lists. It is similar to the way mathematicians describe sets, with a set comprehension, hence the name.
Some attributes of a list comprehension are:
They should be distinct from (nested) for loops and... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Monads/Maybe_monad | Monads/Maybe monad | Demonstrate in your programming language the following:
Construct a Maybe Monad by writing the 'bind' function and the 'unit' (sometimes known as 'return') function for that Monad (or just use what the language already has implemented)
Make two functions, each which take a number and return a monadic number, e.g. Int ... | #J | J |
NB. monad implementation:
unit=: <
bind=: (@>)( :: ])
NB. monad utility
safeVersion=: (<@) ( ::((<_.)"_))
safeCompose=:dyad define
dyad def 'x`:6 bind y'/x,unit y
)
NB. unsafe functions (fail with infinite arguments)
subtractFromSelf=: -~
divideBySelf=: %~
NB. wrapped functions:
safeSubtractFromSelf=: subtrac... | Give a code snippet in #J
Demonstrate in your programming language the following:
Construct a Maybe Monad by writing the 'bind' function and the 'unit' (sometimes known as 'return') function for that Monad (or just use what the language already has implemented)
Make two functions, each which take a number and return ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Split_a_character_string_based_on_change_of_character | Split a character string based on change of character |
Task
Split a (character) string into comma (plus a blank) delimited
strings based on a change of character (left to right).
Show the output here (use the 1st example below).
Blanks should be treated as any other character (except
they are problematic to display clearly). The same applies
to commas.
Fo... | #COBOL | COBOL |
identification division.
program-id. split-ch.
data division.
1 split-str pic x(30) value space.
88 str-1 value "gHHH5YY++///\".
88 str-2 value "gHHH5 ))YY++,,,///\".
1 binary.
2 ptr pic 9(4) value 1.
2 str-start pic 9(4) value 1.
2 delim-len p... | Give a code snippet in #COBOL
Task
Split a (character) string into comma (plus a blank) delimited
strings based on a change of character (left to right).
Show the output here (use the 1st example below).
Blanks should be treated as any other character (except
they are problematic to display clearly). Th... | 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
| #Python | Python | print "Hello world!" | Give a code snippet in #Python
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/Subtractive_generator | Subtractive generator | A subtractive generator calculates a sequence of random numbers, where each number is congruent to the subtraction of two previous numbers from the sequence.
The formula is
r
n
=
r
(
n
−
i
)
−
r
(
n
−
j
)
(
mod
m
)
{\displaystyle r_{n}=r_{(n-i)}-r_{(n-j)}{\pmod {m}}}
for some fixed values of... | #Fortran | Fortran | module subgenerator
implicit none
integer, parameter :: modulus = 1000000000
integer :: s(0:54), r(0:54)
contains
subroutine initgen(seed)
integer :: seed
integer :: n, rnum
s(0) = seed
s(1) = 1
do n = 2, 54
s(n) = mod(s(n-2) - s(n-1), modulus)
if (s(n) < 0) s(n) = s(n) + modulus
en... | Give a code snippet in #Fortran
A subtractive generator calculates a sequence of random numbers, where each number is congruent to the subtraction of two previous numbers from the sequence.
The formula is
r
n
=
r
(
n
−
i
)
−
r
(
n
−
j
)
(
mod
m
)
{\displaystyle r_{n}=r_{(n-i)}-r_{(n-j)}{\pmod... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compiler/code_generator | Compiler/code generator | A code generator translates the output of the syntax analyzer and/or semantic analyzer
into lower level code, either assembly, object, or virtual.
Task[edit]
Take the output of the Syntax analyzer task - which is a flattened Abstract Syntax Tree (AST) - and convert it to virtual machine code, that can be run by the
Vi... | #Forth | Forth | CREATE BUF 0 ,
: PEEK BUF @ 0= IF KEY BUF ! THEN BUF @ ;
: GETC PEEK 0 BUF ! ;
: SPACE? DUP BL = SWAP 9 14 WITHIN OR ;
: >SPACE BEGIN PEEK SPACE? WHILE GETC DROP REPEAT ;
: DIGIT? 48 58 WITHIN ;
: >Integer >SPACE 0
BEGIN PEEK DIGIT?
WHILE GETC [CHAR] 0 - SWAP 10 * + REPEAT ;
: SKIP ( xt --)
B... | Give a code snippet in #Forth
A code generator translates the output of the syntax analyzer and/or semantic analyzer
into lower level code, either assembly, object, or virtual.
Task[edit]
Take the output of the Syntax analyzer task - which is a flattened Abstract Syntax Tree (AST) - and convert it to virtual machine ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_language_name_in_3D_ASCII | Write language name in 3D ASCII | Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
draw a Deathstar
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | locs = Position[
ImageData[Binarize[Rasterize["Mathematica", ImageSize -> 150]]], 0];
Print[StringRiffle[
StringJoin /@
ReplacePart[
ReplacePart[
ConstantArray[
" ", {Max[locs[[All, 1]]] + 1, Max[locs[[All, 2]]] + 1}],
locs -> "\\"], Map[# + 1 &, locs, {2}] -> "#"], "\n"]]; | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Write/display a language's name in 3D ASCII.
(We can leave the definition of "3D ASCII" fuzzy,
so long as the result is interesting or amusing,
not a cheap hack to satisfy the task.)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
d... | 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
| #Groovy | Groovy | def sha256Hash = { text ->
java.security.MessageDigest.getInstance("SHA-256").digest(text.bytes)
.collect { String.format("%02x", it) }.join('')
} | Give a code snippet in #Groovy
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: 764faf5c61ac315f1497f9dfa542713965b7... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mind_boggling_card_trick | Mind boggling card trick | Mind boggling card trick
You are encouraged to solve this task according to the task description, using any language you may know.
Matt Parker of the "Stand Up Maths channel" has a YouTube video of a card trick that creates a semblance of order from chaos.
The task is to simulate the trick in a way that mimics th... | #AutoHotkey | AutoHotkey | ;==========================================================
; create cards
cards := [], suits := ["♠","♥","♦","♣"], num := 0
for i, v in StrSplit("A,2,3,4,5,6,7,8,9,10,J,Q,K",",")
for i, suit in suits
cards[++num] := v suit
;==========================================================
; create gui
w := 40
Gui, font, S... | Give a code snippet in #AutoHotkey
Mind boggling card trick
You are encouraged to solve this task according to the task description, using any language you may know.
Matt Parker of the "Stand Up Maths channel" has a YouTube video of a card trick that creates a semblance of order from chaos.
The task is to simula... | 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
... | #Ursala | Ursala | #import std
#import nat
prime = ~<{0,1}&& -={2,3}!| ~&h&& (all remainder)^Dtt/~& iota@K31 | Give a code snippet in #Ursala
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 loop... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #S-lang | S-lang | variable old = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
variable new = "NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm";
define rot13(s) {
s = strtrans(s, old, new);
return s;
}
define rot13_stream(s) {
variable ln;
while (-1 != fgets(&ln, s))
fputs(rot13(ln), stdout);
}
if (__arg... | Give a code snippet in #S-lang
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-1... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_an_object_method | Call an object method | In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static or class method, and an instance m... | #zkl | zkl | class C{var v; fcn f{v}}
C.f() // call function f in class C
C.v=5; c2:=C(); // create new instance of C
println(C.f()," ",c2.f()) //-->5 Void
C.f.isStatic //--> False
class [static] D{var v=123; fcn f{v}}
D.f(); D().f(); // both return 123
D.f.isStatic //-->False
class E{var v; fcn f{}} E.f.isStatic //-->True | Give a code snippet in #zkl
In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static or cl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Display_an_outline_as_a_nested_table | Display an outline as a nested table |
Display an outline as a nested table.
Parse the outline to a tree,
count the leaves descending from each node,
and write out a table with 'colspan' values
measuring the indent of each line,
translating the indentation to a nested structure,
and padding the tree to even depth.
defining the width of a ... | #AutoHotkey | AutoHotkey | outline2table(db, Delim:= "`t"){
oNum:=[], oMID:=[], oNod := [], oKid := [], oPnt := [], oMbr := [], oLvl := []
oCrl := ["#ffffe6;", "#ffebd2;", "#f0fff0;", "#e6ffff;", "#ffeeff;"]
col := 0, out := "", anc := ""
; create numerical index for each line
for i, line in StrSplit(db, "`n", "`r")
{
RegExMatch(line, ... | Give a code snippet in #AutoHotkey
Display an outline as a nested table.
Parse the outline to a tree,
count the leaves descending from each node,
and write out a table with 'colspan' values
measuring the indent of each line,
translating the indentation to a nested structure,
and padding the tree to ev... | 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
| #Lingo | Lingo | -- load Lingo code from file
fp = xtra("fileIO").new()
fp.openFile(_movie.path&"someinclude.ls", 1)
code = fp.readFile()
fp.closeFile()
-- create new script member, assign loaded code
m = new(#script)
m.name = "someinclude"
m.scriptText = code
-- use it instantly in the current script (i.e. the script that containe... | Give a code snippet in #Lingo
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/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... | #Rust | Rust | extern crate csv;
extern crate getopts;
extern crate gnuplot;
extern crate nalgebra;
extern crate num;
extern crate rand;
extern crate rustc_serialize;
extern crate test;
use getopts::Options;
use gnuplot::{Axes2D, AxesCommon, Color, Figure, Fix, PointSize, PointSymbol};
use nalgebra::{DVector, Iterable};
use rand::{... | Give a code snippet in #Rust
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 datase... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Concurrent_computing | Concurrent computing | Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your language.
| #Scala | Scala | import scala.actors.Futures
List("Enjoy", "Rosetta", "Code").map { x =>
Futures.future {
Thread.sleep((Math.random * 1000).toInt)
println(x)
}
}.foreach(_()) | Give a code snippet in #Scala
Task
Using either native language concurrency syntax or freely available libraries, write a program to display the strings "Enjoy" "Rosetta" "Code", one string per line, in random order.
Concurrency syntax must use threads, tasks, co-routines, or whatever concurrency is called in your l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Selection_sort | Sorting algorithms/Selection 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
... | #BASIC | BASIC |
10 'SAVE"SELSORT",A
20 ' Selection Sort Algorithm
30 '
40 ' VAR
50 DEFINT A-Z
60 OPTION BASE 1
70 I=0: J=0: IMINV = 0: IMAX = 0: TP! = 0: TL! = 0
80 '
90 CLS
100 PRINT "This program does the Selection Sort Algorithm"
110 INPUT "Number of elements to sort (Max=1000, Enter=10)";IMAX
120 IF IMAX = 0 THEN IMAX = 10
130 I... | Give a code snippet in #BASIC
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 so... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_duplicate_elements | Remove duplicate elements |
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
... | #Run_BASIC | Run BASIC | a$ = "2 3 5 7 11 13 17 19 cats 222 -100.2 +11 1.1 +7 7. 7 5 5 3 2 0 4.4 2"
for i = 1 to len(a$)
a1$ = word$(a$,i)
if a1$ = "" then exit for
for i1 = 1 to len(b$)
if a1$ = word$(b$,i1) then [nextWord]
next i1
b$ = b$ + a1$ + " "
[nextWord]
next i
print "Dups:";a$
print "No Dups:";b$ | Give a code snippet in #Run_BASIC
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Take_notes_on_the_command_line | Take notes on the command line | Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES.TXT followed by a newline.
Then al... | #Groovy | Groovy | def notes = new File('./notes.txt')
if (args) {
notes << "${new Date().format('YYYY-MM-dd HH:mm:ss')}\t${args.join(' ')}\n"
} else {
println notes.text
}
| Give a code snippet in #Groovy
Take notes on the command line is part of Short Circuit's Console Program Basics selection.
Invoking NOTES without commandline arguments displays the current contents of the local NOTES.TXT if it exists.
If NOTES has arguments, the current date and time are appended to the local NOTES.TX... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_cuboid | Draw a cuboid | Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection is acceptable for this task.
R... | #Kotlin | Kotlin | // version 1.1
import java.awt.*
import java.awt.event.MouseAdapter
import java.awt.event.MouseEvent
import javax.swing.*
class Cuboid: JPanel() {
private val nodes = arrayOf(
doubleArrayOf(-1.0, -1.0, -1.0),
doubleArrayOf(-1.0, -1.0, 1.0),
doubleArrayOf(-1.0, 1.0, -1.0),
doubl... | Give a code snippet in #Kotlin
Task
Draw a cuboid with relative dimensions of 2 × 3 × 4.
The cuboid can be represented graphically, or in ASCII art, depending on the language capabilities.
To fulfill the criteria of being a cuboid, three faces must be visible.
Either static or rotational projection i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Environment_variables | Environment variables | Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| #Modula-3 | Modula-3 | MODULE EnvVars EXPORTS Main;
IMPORT IO, Env;
VAR
k, v: TEXT;
BEGIN
IO.Put(Env.Get("HOME") & "\n");
FOR i := 0 TO Env.Count - 1 DO
Env.GetNth(i, k, v);
IO.Put(k & " = " & v & "\n")
END
END EnvVars. | Give a code snippet in #Modula-3
Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Statistics/Basic | Statistics/Basic | Statistics is all about large groups of numbers.
When talking about a set of sampled data, most frequently used is their mean value and standard deviation (stddev).
If you have set of data
x
i
{\displaystyle x_{i}}
where
i
=
1
,
2
,
…
,
n
{\displaystyle i=1,2,\ldots ,n\,\!}
, the mean is
x
¯... | #Lasso | Lasso | define stat1(a) => {
if(#a->size) => {
local(mean = (with n in #a sum #n) / #a->size)
local(sdev = math_pow(((with n in #a sum Math_Pow((#n - #mean),2)) / #a->size),0.5))
return (:#sdev, #mean)
else
return (:0,0)
}
}
define stat2(a) => {
if(#a->size) => {
local(sx = 0, sxx = 0)
with x in #a do => {
#... | Give a code snippet in #Lasso
Statistics is all about large groups of numbers.
When talking about a set of sampled data, most frequently used is their mean value and standard deviation (stddev).
If you have set of data
x
i
{\displaystyle x_{i}}
where
i
=
1
,
2
,
…
,
n
{\displaystyle i=1,2,\ldots ,n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Almost_prime | Almost prime | A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, where
k
=
2
{\displaystyl... | #Factor | Factor | USING: formatting fry kernel lists lists.lazy locals
math.combinatorics math.primes.factors math.ranges sequences ;
IN: rosetta-code.almost-prime
: k-almost-prime? ( n k -- ? )
'[ factors _ <combinations> [ product ] map ]
[ [ = ] curry ] bi any? ;
:: first10 ( k -- seq )
10 0 lfrom [ k k-almost-prime? ... | Give a code snippet in #Factor
A k-Almost-prime is a natural number
n
{\displaystyle n}
that is the product of
k
{\displaystyle k}
(possibly identical) primes.
Example
1-almost-primes, where
k
=
1
{\displaystyle k=1}
, are the prime numbers themselves.
2-almost-primes, w... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arbitrary-precision_integers_(included) | Arbitrary-precision integers (included) | Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | #11l | 11l | V y = String(BigInt(5) ^ 4 ^ 3 ^ 2)
print(‘5^4^3^2 = #....#. and has #. digits’.format(y[0.<20], y[(len)-20..], y.len)) | Give a code snippet in #11l
Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Graphical | Hello world/Graphical |
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| #Vlang | Vlang | import ui
fn main() {
ui.message_box('Hello World')
} | Give a code snippet in #Vlang
Task
Display the string Goodbye, World! on a GUI object (alert box, plain window, text area, etc.).
Related task
Hello world/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Menu | Menu | Task
Given a prompt and a list containing a number of strings of which one is to be selected, create a function that:
prints a textual menu formatted as an index value followed by its corresponding string for each item in the list;
prompts the user to enter a number;
returns the string corresponding to the selecte... | #Run_BASIC | Run BASIC | dim choose$(5)
choose$(1) = "1 Fee Fie"
choose$(2) = "2 Huff Puff"
choose$(3) = "3 Mirror, Mirror"
choose$(4) = "4 Tick, Tock"
choose$(5) = "Exit"
[start]
print "Menu Selection"
listbox #lb,choose$(),5
button #sel, "Accept",[select]
wait
[select]
selected$=#lb selection$()
print " "
if selected$<>"" then
print "Y... | Give a code snippet in #Run_BASIC
Task
Given a prompt and a list containing a number of strings of which one is to be selected, create a function that:
prints a textual menu formatted as an index value followed by its corresponding string for each item in the list;
prompts the user to enter a number;
returns the ... | christopher/rosetta-code |
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