task_url stringlengths 30 116 | task_name stringlengths 2 86 | task_description stringlengths 0 14.4k | language_url stringlengths 2 53 | language_name stringlengths 1 52 | code stringlengths 0 61.9k | response_seed stringclasses 1
value | instruction_seed stringlengths 27 14.4k | _source stringclasses 1
value |
|---|---|---|---|---|---|---|---|---|
http://rosettacode.org/wiki/Topological_sort | Topological 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
... | #Object_Pascal | Object Pascal |
program topologicalsortrosetta;
{*
Topological sorter to parse e.g. dependencies.
Written for FreePascal 2.4.x/2.5.1. Probably works in Delphi, but you'd have to
change some units.
*}
{$IFDEF FPC}
// FreePascal-specific setup
{$mode objfpc}
uses {$IFDEF UNIX}
cwstring, {* widestring support for unix *} {$IFDEF Us... | Give a code snippet in #Object_Pascal
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Increment_loop_index_within_loop_body | Loops/Increment loop index within loop body | Sometimes, one may need (or want) a loop which
its iterator (the index
variable) is modified within the
loop body in addition to the normal incrementation by the (do) loop structure index.
Goal
Demonstrate the best way to accomplish this.
Task
Write a loop which:
starts the index (variable... | #Scala | Scala | import scala.annotation.tailrec
object LoopIncrementWithinBody extends App {
private val (limit, offset) = (42L, 1)
@tailrec
private def loop(i: Long, n: Int): Unit = {
def isPrime(n: Long) =
n > 1 && ((n & 1) != 0 || n == 2) && (n % 3 != 0 || n == 3) &&
((5 to math.sqrt(n).toInt by 2).par... | Give a code snippet in #Scala
Sometimes, one may need (or want) a loop which
its iterator (the index
variable) is modified within the
loop body in addition to the normal incrementation by the (do) loop structure index.
Goal
Demonstrate the best way to accomplish this.
Task
Write a loop which:... | 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... | #Panda | Panda | sum{{1.0.divide(1..1000.sqr)}} | Give a code snippet in #Panda
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback | Guess the number/With feedback | Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the guess is:
higher than the target,
equal to... | #Genie | Genie | [indent=4]
/*
Number guessing with feedback, in Genie
from https://wiki.gnome.org/Projects/Genie/AdvancedSample
valac numberGuessing.gs
./numberGuessing
*/
class NumberGuessing
prop min:int
prop max:int
construct(m:int, n:int)
self.min = m
self.max = n
def start()
... | Give a code snippet in #Genie
Task
Write a game (computer program) that follows the following rules:
The computer chooses a number between given set limits.
The player is asked for repeated guesses until the the target number is guessed correctly
At each guess, the computer responds with whether the guess is:
hi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Show_ASCII_table | Show ASCII table | Task
Show the ASCII character set from values 32 to 127 (decimal) in a table format.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioin... | #Common_Lisp | Common Lisp | (setq startVal 32)
(setq endVal 127)
(setq cols 6)
(defun print-val (val) "Prints the value for that ascii number"
(cond
((= val 32) (format t " 32: SPC "))
((= val 127) (format t "127: DEL~%"))
((and (zerop (mod (- val startVal) cols)) (< val 100)) (format t "~% ~d: ~a " val (int-char val)))
((and (zerop... | Give a code snippet in #Common_Lisp
Task
Show the ASCII character set from values 32 to 127 (decimal) in a table format.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and sto... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Order_two_numerical_lists | Order two numerical lists | sorting
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
She... | #PureBasic | PureBasic | DataSection
Array_1:
Data.i 5 ;element count
Data.i 1, 2, 3, 4, 5 ;element data
Array_2:
Data.i 6
Data.i 1, 2, 1, 5, 2, 2
Array_3:
Data.i 5
Data.i 1, 2, 1, 5, 2
Array_4:
Data.i 5
Data.i 1, 2, 1, 5, 2
Array_5:
Data.i 4
Data.i 1, 2, 1, 6
Array_6:
Data.i 5
Data.i 1, 2, 1, ... | Give a code snippet in #PureBasic
sorting
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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
| #HolyC | HolyC | "Hello world!\n"; | Give a code snippet in #HolyC
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/Higher-order_functions | Higher-order functions | Task
Pass a function as an argument to another function.
Related task
First-class functions
| #PureBasic | PureBasic | Prototype.d func(*text$)
Procedure NumberTwo(arg$)
Debug arg$
EndProcedure
Procedure NumberOne(*p, text$)
Define MyFunc.func=*p
MyFunc(@text$)
EndProcedure
NumberOne(@NumberTwo(),"Hello Worldy!") | Give a code snippet in #PureBasic
Task
Pass a function as an argument to another function.
Related task
First-class functions
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Luhn_test_of_credit_card_numbers | Luhn test of credit card numbers | The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order of the digits in the number.
Tak... | #Pascal | Pascal | program luhnTestOfCreditCardNumbers(input, output);
type
{
`string(…)` is an Extended Pascal, ISO 10206, extension.
`string(64)` discriminates the “schema” data type `string`
to contain at most 64 `char` values.
}
creditCardNumber = string(64);
{
\brief determines whether a string contains digits only
... | Give a code snippet in #Pascal
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order o... | 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... | #Wren | Wren | import "io" for Stdin, Stdout
import "/str" for Char
var hle
var lowest = 1
var highest = 20
var guess = 10
System.print("Please choose a number between 1 and 20 but don't tell me what it is yet\n")
while (true) {
System.print("My guess is %(guess)")
while (true) {
System.write("Is this higher/lower... | Give a code snippet in #Wren
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 c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua... | #Z80_Assembly | Z80 Assembly | cp b
jr nz,B_False
cp c
jr z,doubleTrue
;B true, C false
;your code goes here
jp done
B_False:
cp c
jr nz,doubleFalse
;B false, C true
;your code goes here
jp done
doubleTrue:
;your code goes here
jp done
doubleFalse:
;your code goes here
jp done
done:
;rest of prog... | Give a code snippet in #Z80_Assembly
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most language... | 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... | #Smalltalk | Smalltalk | [
|first second done|
first := Random nextIntegerBetween:0 and:19.
Stdout print:first; cr.
(done := (first == 10)) ifFalse:[
second := Random nextIntegerBetween:0 and:19.
Stdout print:' '; print:second; cr.
].
done
] whileFalse | Give a code snippet in #Smalltalk
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 loo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Isqrt_(integer_square_root)_of_X | Isqrt (integer square root) of X | Sometimes a function is needed to find the integer square root of X, where X can be a
real non─negative number.
Often X is actually a non─negative integer.
For the purposes of this task, X can be an integer or a real number, but if it
simplifies things in your computer programming language, assume... | #Forth | Forth |
: d., ( n -- ) \ write double precision int, commatized.
tuck dabs
<# begin 2dup 1.000 d> while # # # [char] , hold repeat #s rot sign #>
type space ;
: ., ( n -- ) \ write integer commatized.
s>d d., ;
: 4* s" 2 lshift" evaluate ; immediate
: 4/ s" 2 rshift" evaluate ; immediate
: isqrt-... | Give a code snippet in #Forth
Sometimes a function is needed to find the integer square root of X, where X can be a
real non─negative number.
Often X is actually a non─negative integer.
For the purposes of this task, X can be an integer or a real number, but if it
simplifies things in your computer... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Set_puzzle | Set puzzle | Set Puzzles are created with a deck of cards from the Set Game™. The object of the puzzle is to find sets of 3 cards in a rectangle of cards that have been dealt face up.
There are 81 cards in a deck.
Each card contains a unique variation of the following four features: color, symbol, number and shading.
there are... | #Go | Go | package main
import (
"fmt"
"math/rand"
"time"
)
const (
number = [3]string{"1", "2", "3"}
color = [3]string{"red", "green", "purple"}
shade = [3]string{"solid", "open", "striped"}
shape = [3]string{"oval", "squiggle", "diamond"}
)
type card int
func (c card) String() string {
... | Give a code snippet in #Go
Set Puzzles are created with a deck of cards from the Set Game™. The object of the puzzle is to find sets of 3 cards in a rectangle of cards that have been dealt face up.
There are 81 cards in a deck.
Each card contains a unique variation of the following four features: color, symbol, num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Legendre_prime_counting_function | Legendre prime counting function | The prime-counting function π(n) computes the number of primes not greater than n. Legendre was the first mathematician to create a formula to compute π(n) based on the inclusion/exclusion principle.
To calculate:
Define
φ(x, 0) = x
φ(x, a) = φ(x, a−1) − φ(⌊x/pa⌋, a−1), where pa is the ath prime number.
then
π(n) ... | #Phix | Phix | with javascript_semantics
--
-- While a phix dictionary can handle keys of {x,a}, for this
-- task performance was dreadful (7,612,479 entries, >3mins),
-- so instead memophix maps known x to an index to memophia
-- which holds the full [1..a] for each x, dropping to a much
-- more respectable (albeit not super-fast)... | Give a code snippet in #Phix
The prime-counting function π(n) computes the number of primes not greater than n. Legendre was the first mathematician to create a formula to compute π(n) based on the inclusion/exclusion principle.
To calculate:
Define
φ(x, 0) = x
φ(x, a) = φ(x, a−1) − φ(⌊x/pa⌋, a−1), where pa is the ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_numbers | Random numbers | Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Related task
Standard deviation
| #Maxima | Maxima | load(distrib)$
random_normal(1.0, 0.5, 1000); | Give a code snippet in #Maxima
Task
Generate a collection filled with 1000 normally distributed random (or pseudo-random) numbers
with a mean of 1.0 and a standard deviation of 0.5
Many libraries only generate uniformly distributed random numbers. If so, you may use one of these algorithms.
Relate... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Closest-pair_problem | Closest-pair problem |
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Provide a function to find the closest two p... | #PureBasic | PureBasic | Procedure.d bruteForceClosestPair(Array P.coordinate(1))
Protected N=ArraySize(P()), i, j
Protected mindistance.f=Infinity(), t.d
Shared a, b
If N<2
a=0: b=0
Else
For i=0 To N-1
For j=i+1 To N
t=Pow(Pow(P(i)\x-P(j)\x,2)+Pow(P(i)\y-P(j)\y,2),0.5)
If mindistance>t
mindist... | Give a code snippet in #PureBasic
This page uses content from Wikipedia. The original article was at Closest pair of points problem. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Provide a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Display_an_extended_character | Terminal control/Display an extended character | Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| #BBC_BASIC | BBC BASIC | PRINT "£" | Give a code snippet in #BBC_BASIC
Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #ATS | ATS |
(* ****** ****** *)
//
#include
"share/atspre_staload.hats"
// ... | Give a code snippet in #ATS
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Currying | Currying |
This page uses content from Wikipedia. The original article was at Currying. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Create a simple demonstrative example of Currying in a specific la... | #Delphi | Delphi |
program Currying;
{$APPTYPE CONSOLE}
{$R *.res}
uses
System.SysUtils;
var
Plus: TFunc<Integer, TFunc<Integer, Integer>>;
begin
Plus :=
function(x: Integer): TFunc<Integer, Integer>
begin
result :=
function(y: Integer): Integer
begin
result := x + y;
end;
... | Give a code snippet in #Delphi
This page uses content from Wikipedia. The original article was at Currying. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Create a simple demonstrative exam... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file_on_magnetic_tape | Create a file on magnetic tape | The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| #REXX | REXX | /*REXX pgm demonstrates writing records to an attached magnetic tape.*/
dsName = 'TAPE.FILE' /*dsName of "file" being written.*/
do j=1 for 100 /*write 100 records to mag tape. */
call lineout dsName, 'this is record' j || "."
end /*j*/
... | Give a code snippet in #REXX
The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #Clojure | Clojure | (concat [1 2 3] [4 5 6]) | Give a code snippet in #Clojure
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Calendar_-_for_%22REAL%22_programmers | Calendar - for "REAL" programmers | Task
Provide an algorithm as per the Calendar task, except the entire code for the algorithm must be presented entirely without lowercase.
Also - as per many 1969 era line printers - format the calendar to nicely fill a page that is 132 characters wide.
(Hint: manually convert the code from the Calendar task to al... | #Ada | Ada | WITH PRINTABLE_CALENDAR;
PROCEDURE REAL_CAL IS
C: PRINTABLE_CALENDAR.CALENDAR := PRINTABLE_CALENDAR.INIT_132
((WEEKDAY_REP =>
"MO TU WE TH FR SA SO",
MONTH_REP =>
(" JANUARY ", " FEBRUARY ",
" MARCH ", " APRIL ",
... | Give a code snippet in #Ada
Task
Provide an algorithm as per the Calendar task, except the entire code for the algorithm must be presented entirely without lowercase.
Also - as per many 1969 era line printers - format the calendar to nicely fill a page that is 132 characters wide.
(Hint: manually convert the code... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FTP | FTP | Task
Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
| #Tcl | Tcl |
package require ftp
set conn [::ftp::Open kernel.org anonymous "" -mode passive]
::ftp::Cd $conn /pub/linux/kernel
foreach line [ftp::NList $conn] {
puts $line
}
::ftp::Type $conn binary
::ftp::Get $conn README README
| Give a code snippet in #Tcl
Task
Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Forward_difference | Forward difference | Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
List B should have one fewer elem... | #11l | 11l | V dif = s -> enumerate(s[1..]).map2((i, x) -> x - @s[i])
F difn(s, n) -> [Int]
R I n != 0 {difn(dif(s), n - 1)} E s
V s = [90, 47, 58, 29, 22, 32, 55, 5, 55, 73]
L(i) 10
print(difn(s, i)) | Give a code snippet in #11l
Task
Provide code that produces a list of numbers which is the nth order forward difference, given a non-negative integer (specifying the order) and a list of numbers.
The first-order forward difference of a list of numbers A is a new list B, where Bn = An+1 - An.
List B... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Farey_sequence | Farey sequence | The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a Farey series.
Each Farey se... | #Prolog | Prolog | task(1) :-
between(1, 11, I),
farey(I, F),
write(I), write(': '),
rwrite(F), nl, fail; true.
task(2) :- between(1, 10, I),
I100 is I*100,
farey( I100, F),
length(F,N),
write('|F('), write(I100), write(')| = '), writeln(N), fail; true.
% farey(+Order, Sequence)
farey(Order, Sequence) :-
bagof( R,
I^J^(be... | Give a code snippet in #Prolog
The Farey sequence Fn of order n is the sequence of completely reduced fractions between 0 and 1 which, when in lowest terms, have denominators less than or equal to n, arranged in order of increasing size.
The Farey sequence is sometimes incorrectly called a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Primality_by_Wilson%27s_theorem | Primality by Wilson's theorem | Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.
Wikipedia: Wilson's theorem
| #C.2B.2B | C++ | #include <iomanip>
#include <iostream>
int factorial_mod(int n, int p) {
int f = 1;
for (; n > 0 && f != 0; --n)
f = (f * n) % p;
return f;
}
bool is_prime(int p) {
return p > 1 && factorial_mod(p - 1, p) == p - 1;
}
int main() {
std::cout << " n | prime?\n------------\n";
std::co... | Give a code snippet in #C.2B.2B
Task
Write a boolean function that tells whether a given integer is prime using Wilson's theorem.
By Wilson's theorem, a number p is prime if and only if p divides (p - 1)! + 1.
Remember that 1 and all non-positive integers are not prime.
See also
Cut-the-knot: Wilson's theorem.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cholesky_decomposition | Cholesky decomposition | Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose:
A
=
L
L
T
{\displaystyle A=LL^{T}}
L
{\displaystyle L}
is called the Cholesky factor of
A
{\displaystyle A}
, and can be interpreted as a generalized square r... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | CholeskyDecomposition[{{25, 15, -5}, {15, 18, 0}, {-5, 0, 11}}] | Give a code snippet in #Mathematica_.2F_Wolfram_Language
Every symmetric, positive definite matrix A can be decomposed into a product of a unique lower triangular matrix L and its transpose:
A
=
L
L
T
{\displaystyle A=LL^{T}}
L
{\displaystyle L}
is called the Cholesky factor of
A
{\displayst... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Zero_to_the_zero_power | Zero to the zero power | Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or 0^0 at compile time, ... | #ERRE | ERRE |
.....
PRINT(0^0)
.....
| Give a code snippet in #ERRE
Some computer programming languages are not exactly consistent (with other computer programming languages)
when raising zero to the zeroth power: 00
Task
Show the results of raising zero to the zeroth power.
If your computer language objects to 0**0 or ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multisplit | Multisplit | It is often necessary to split a string into pieces
based on several different (potentially multi-character) separator strings,
while still retaining the information about which separators were present in the input.
This is particularly useful when doing small parsing tasks.
The task is to write code to demonstrate ... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | StringSplit["a!===b=!=c", {"==", "!=", "="}] | Give a code snippet in #Mathematica.2FWolfram_Language
It is often necessary to split a string into pieces
based on several different (potentially multi-character) separator strings,
while still retaining the information about which separators were present in the input.
This is particularly useful when doing small pa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hostname | Hostname | Task
Find the name of the host on which the routine is running.
| #Kotlin | Kotlin | // version 1.1.4
import java.net.InetAddress
fun main(args: Array<String>) {
println(InetAddress.getLocalHost().hostName)
} | Give a code snippet in #Kotlin
Task
Find the name of the host on which the routine is running.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Z80_Assembly | Z80 Assembly | PrintChar equ $BB5A ;Amstrad CPC bios call
Terminator equ 0 ;null terminator for strings
org $8000
ld hl, StringA
call ReverseString
ld hl, StringA
call PrintString
ret ;return to basic
StringA:
byte "12345678",0
;;;; SUBROUTINES
GetStringLength:
;HL = STRING. RETURNS LENGTH IN B. LENGTH... | Give a code snippet in #Z80_Assembly
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game/Solve | 24 game/Solve | task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| #Wren | Wren | import "random" for Random
import "/dynamic" for Tuple, Enum, Struct
var N_CARDS = 4
var SOLVE_GOAL = 24
var MAX_DIGIT = 9
var Frac = Tuple.create("Frac", ["num", "den"])
var OpType = Enum.create("OpType", ["NUM", "ADD", "SUB", "MUL", "DIV"])
var Expr = Struct.create("Expr", ["op", "left", "right", "value"])
... | Give a code snippet in #Wren
task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Date_format | Date format | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| #PicoLisp | PicoLisp | (let (Date (date) Lst (date Date))
(prinl (dat$ Date "-")) # 2010-02-19
(prinl # Friday, February 19, 2010
(day Date)
", "
(get *MonFmt (cadr Lst))
" "
(caddr Lst)
", "
(car Lst) ) ) | Give a code snippet in #PicoLisp
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Task
Display the current date in the formats of:
2007-11-23 and
Friday, November 23, 2007
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Scala | Scala | def gcd(a: Int, b: Int): Int = if (b == 0) a.abs else gcd(b, a % b) | Give a code snippet in #Scala
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Creation | Associative array/Creation | Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element ins... | #Dart | Dart |
main() {
var rosettaCode = { // Type is inferred to be Map<String, String>
'task': 'Associative Array Creation'
};
rosettaCode['language'] = 'Dart';
// The update function can be used to update a key using a callback
rosettaCode.update( 'is fun', // Key to update
(value) => "i don't know", // New value ... | Give a code snippet in #Dart
Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, E... | 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... | #Kotlin | Kotlin | // version 1.1.2
fun <T> ncs(a: Array<T>) {
fun generate(m: Int, k: Int, c: IntArray) {
if (k == m) {
if (c[m - 1] != c[0] + m - 1) {
for (i in 0 until m) print("${a[c[i]]} ")
println()
}
}
else {
for (j... | Give a code snippet in #Kotlin
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 a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strong_and_weak_primes | Strong and weak primes |
Definitions (as per number theory)
The prime(p) is the pth prime.
prime(1) is 2
prime(4) is 7
A strong prime is when prime(p) is > [prime(p-1) + prime(p+1)] ÷ 2
A weak prime is when prime(p) is < [prime(p-1) + prime(p+1)] ÷ 2
Note that the defin... | #AWK | AWK |
# syntax: GAWK -f STRONG_AND_WEAK_PRIMES.AWK
BEGIN {
for (i=1; i<1E7; i++) {
if (is_prime(i)) {
arr[++n] = i
}
}
# strong:
stop1 = 36 ; stop2 = 1E6 ; stop3 = 1E7
count1 = count2 = count3 = 0
printf("The first %d strong primes:",stop1)
for (i=2; count1<stop1; i++) {
if... | Give a code snippet in #AWK
Definitions (as per number theory)
The prime(p) is the pth prime.
prime(1) is 2
prime(4) is 7
A strong prime is when prime(p) is > [prime(p-1) + prime(p+1)] ÷ 2
A weak prime is when prime(p) is < [prime(p-1) + prime(p+... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Balanced_ternary | Balanced ternary | Balanced ternary is a way of representing numbers. Unlike the prevailing binary representation, a balanced ternary integer is in base 3, and each digit can have the values 1, 0, or −1.
Examples
Decimal 11 = 32 + 31 − 30, thus it can be written as "++−"
Decimal 6 = 32 − 31 + 0 × 30, thus it can be written as "+−0"
... | #FreeBASIC | FreeBASIC |
#define MAX(a, b) iif((a) > (b), (a), (b))
Dim Shared As Integer pow, signo
Dim Shared As String t
t = "-0+"
Function deci(cadena As String) As Integer
Dim As Integer i, deci1
Dim As String c1S
pow = 1
For i = Len(cadena) To 1 Step -1
c1S = Mid(cadena,i,1)
signo = Instr(t, c1S)-2
... | Give a code snippet in #FreeBASIC
Balanced ternary is a way of representing numbers. Unlike the prevailing binary representation, a balanced ternary integer is in base 3, and each digit can have the values 1, 0, or −1.
Examples
Decimal 11 = 32 + 31 − 30, thus it can be written as "++−"
Decimal 6 = 32 − 31 + 0 × 3... | 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
| #Oz | Oz | {OS.system "ls" _} | Give a code snippet in #Oz
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/Handle_a_signal | Handle a signal | Most operating systems provide interrupt facilities, sometimes called signals either generated by the user or as a result of program failure or reaching a limit like file space.
Unhandled signals generally terminate a program in a disorderly manner.
Signal handlers are created so that the program behaves in a well-defi... | #C.2B.2B | C++ | #include <chrono>
#include <csignal>
#include <ctime>
#include <iostream>
#include <thread>
volatile sig_atomic_t gotint = 0;
void handler(int signum) {
// Set a flag for handling the signal, as other methods like printf are not safe here
gotint = 1;
}
int main() {
using namespace std;
signal(SIGINT, handle... | Give a code snippet in #C.2B.2B
Most operating systems provide interrupt facilities, sometimes called signals either generated by the user or as a result of program failure or reaching a limit like file space.
Unhandled signals generally terminate a program in a disorderly manner.
Signal handlers are created so that t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_matching | String matching |
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 |... | #Ring | Ring |
aString = "Welcome to the Ring Programming Language"
bString = "Ring"
bStringIndex = substr(aString,bString)
if bStringIndex > 0 see "" + bStringIndex + " : " + bString ok
| Give a code snippet in #Ring
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
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_an_array_of_composite_structures | Sort an array of composite structures |
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
... | #PureBasic | PureBasic | Structure MyPair ; Define a structured data type
Name$
Value.i
EndStructure
Dim People.MyPair(2) ; Allocate some elements
People(0)\Name$ = "John" ; Start filling them in
People(0)\Value = 100
People(1)\Name$ = "Emma"
People(1)\Value = 200
People(2)\Name$ = "Johnny"
People(2)\Value = 175... | Give a code snippet in #PureBasic
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/Magic_8-ball | Magic 8-ball | Task
Create Magic 8-Ball.
See details at: Magic 8-Ball.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurren... | #8080_Assembly | 8080 Assembly | bdos: equ 5 ; CP/M calls
puts: equ 9
gets: equ 10
org 100h
lxi d,message ; Print message
mvi c,puts
call bdos
question: lxi d,prompt ; Ask for question
mvi c,puts
call bdos
lxi d,bufdef ; Read answer
mvi c,gets
call bdos
lxi d,newline ; Print newline
mvi c,puts
call bdos
lxi h,buf ; XOR... | Give a code snippet in #8080_Assembly
Task
Create Magic 8-Ball.
See details at: Magic 8-Ball.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Real_constants_and_functions | Real constants and functions | Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "magnitude")
floor (largest ... | #Lasso | Lasso | //e
define e => 2.7182818284590452
//π
define pi => 3.141592653589793
e
pi
9.0->sqrt
1.64->log
1.64->log10
1.64->exp
1.64->abs
1.64->floor
1.64->ceil
1.64->pow(10.0) | Give a code snippet in #Lasso
Task
Show how to use the following math constants and functions in your language (if not available, note it):
e (base of the natural logarithm)
π
{\displaystyle \pi }
square root
logarithm (any base allowed)
exponential (ex )
absolute value (a.k.a. "m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nested_function | Nested function | In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of two nested functions that prints t... | #Racket | Racket | #lang racket
(define (make-list separator)
(define counter 1)
(define (make-item item)
(begin0
(format "~a~a~a~%" counter separator item)
(set! counter (add1 counter))))
(apply string-append (map make-item '(first second third))))
(display (make-list ". ")) | Give a code snippet in #Racket
In many languages, functions can be nested, resulting in outer functions and inner functions. The inner function can access variables from the outer function. In most languages, the inner function can also modify variables in the outer function.
Task
Write a program consisting of tw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evaluate_binomial_coefficients | Evaluate binomial coefficients | This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2
)
…
(
n
−
k
+
1
)
k
(
k
−
1... | #TI-83_BASIC | TI-83 BASIC | 10 nCr 4 | Give a code snippet in #TI-83_BASIC
This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Solve_a_Numbrix_puzzle | Solve a Numbrix puzzle | Numbrix puzzles are similar to Hidato.
The most important difference is that it is only possible to move 1 node left, right, up, or down (sometimes referred to as the Von Neumann neighborhood).
Published puzzles also tend not to have holes in the grid and may not always indicate the end node.
Two examples follow:
Exam... | #REXX | REXX | /*REXX program solves a Numbrix (R) puzzle, it also displays the puzzle and solution. */
maxR= 0; maxC= 0; maxX= 0; /*define maxR, maxC, and maxX. */
minR= 9e9; minC= 9e9; minX= 9e9; /* " minR, minC, " minX. */
cells= 0 ... | Give a code snippet in #REXX
Numbrix puzzles are similar to Hidato.
The most important difference is that it is only possible to move 1 node left, right, up, or down (sometimes referred to as the Von Neumann neighborhood).
Published puzzles also tend not to have holes in the grid and may not always indicate the end no... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_occurrences_of_a_substring | Count occurrences of a substring | Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
It should return an integer cou... | #Euphoria | Euphoria | function countSubstring(sequence s, sequence sub)
integer from,count
count = 0
from = 1
while 1 do
from = match_from(sub,s,from)
if not from then
exit
end if
from += length(sub)
count += 1
end while
return count
end function
? countSubstring(... | Give a code snippet in #Euphoria
Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for. ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_character_by_character/UTF8 | Read a file character by character/UTF8 | Task
Read a file one character at a time, as opposed to reading the entire file at once.
The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached).
The procedure should support the reading of files contain... | #Haskell | Haskell | #!/usr/bin/env runhaskell
{- The procedure to read a UTF-8 character is just:
hGetChar :: Handle -> IO Char
assuming that the encoding for the handle has been set to utf8.
-}
import System.Environment (getArgs)
import System.IO (
Handle, IOMode (..),
hGetChar, hIsEOF, hSetEncoding, stdin, ... | Give a code snippet in #Haskell
Task
Read a file one character at a time, as opposed to reading the entire file at once.
The solution may be implemented as a procedure, which returns the next character in the file on each consecutive call (returning EOF when the end of the file is reached).
The procedure should sup... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Animation | Animation |
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This task demonstrates this.
Task
Creat... | #Action.21 | Action! | PROC DrawWindow(BYTE x,y,len)
BYTE i
Position(x,y)
Put(17)
FOR i=1 TO len DO Put(18) OD
Put(5)
Position(x,y+1)
Put(124)
Position(x+len+1,y+1)
Put(124)
Position(x,y+2)
Put(26)
FOR i=1 TO len DO Put(18) OD
Put(3)
RETURN
PROC RotateLeft(CHAR ARRAY a)
BYTE i,tmp
IF a(0)<1 THEN RETURN... | Give a code snippet in #Action.21
Animation is integral to many parts of GUIs, including both the fancy effects when things change used in window managers, and of course games. The core of any animation system is a scheme for periodically changing the display while still remaining responsive to the user. This tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_prepend | String prepend |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Var s = "prepend"
s = "String " + s
Print s
Sleep | Give a code snippet in #FreeBASIC
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/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
... | #Racket | Racket | #lang racket
(define answer (number->string (foldr expt 1 '(5 4 3 2))))
(define len (string-length answer))
(printf "Got ~a digits~n" len)
(printf "~a ... ~a~n"
(substring answer 0 20)
(substring answer (- len 20) len))
| Give a code snippet in #Racket
Using the in-built capabilities of your language, calculate the integer value of:
5
4
3
2
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_configuration_file | Read a configuration file | The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicolon are ignored by the application
# pr... | #Visual_Basic | Visual Basic | ' Configuration file parser routines.
'
' (c) Copyright 1993 - 2011 Mark Hobley
'
' This configuration parser contains code ported from an application program
' written in Microsoft Quickbasic
'
' This code can be redistributed or modified under the terms of version 1.2 of
' the GNU Free Documentation Licence as publis... | Give a code snippet in #Visual_Basic
The task is to read a configuration file in standard configuration file format,
and set variables accordingly.
For this task, we have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines beginning with a hash or a semicol... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Topswops | Topswops | Topswops is a card game created by John Conway in the 1970's.
Assume you have a particular permutation of a set of n cards numbered 1..n on both of their faces, for example the arrangement of four cards given by [2, 4, 1, 3] where the leftmost card is on top.
A round is composed of reversing the first ... | #AutoHotkey | AutoHotkey | Topswops(Obj, n){
R := []
for i, val in obj{
if (i <=n)
res := val (A_Index=1?"":",") res
else
res .= "," val
}
Loop, Parse, res, `,
R[A_Index]:= A_LoopField
return R
} | Give a code snippet in #AutoHotkey
Topswops is a card game created by John Conway in the 1970's.
Assume you have a particular permutation of a set of n cards numbered 1..n on both of their faces, for example the arrangement of four cards given by [2, 4, 1, 3] where the leftmost card is on top.
A round ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Introspection | Introspection | Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute abs(bloop).
Extra credit
Repor... | #Oforth | Oforth | : bloopAbs
| bl m |
System.VERSION println
Word find("bloop") ->bl
bl isA(Constant) ifFalse: [ "bloop constant does not exist" println return ]
"abs" asMethod ->m
m ifNull: [ "abs method does not exist" println return ]
System.Out "bloop value is : " << bl value << cr
System.Out "bloop abs ... | Give a code snippet in #Oforth
Task
verify the version/revision of your currently running (compiler/interpreter/byte-compiler/runtime environment/whatever your language uses) and exit if it is too old.
check whether the variable "bloop" exists and whether the math-function "abs()" is available and if yes compute ab... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Best_shuffle | Best shuffle | Task
Shuffle the characters of a string in such a way that as many of the character values are in a different position as possible.
A shuffle that produces a randomized result among the best choices is to be preferred. A deterministic approach that produces the same sequence every time is acceptable as an alternative... | #PicoLisp | PicoLisp | (de bestShuffle (Str)
(let Lst NIL
(for C (setq Str (chop Str))
(if (assoc C Lst)
(con @ (cons C (cdr @)))
(push 'Lst (cons C)) ) )
(setq Lst (apply conc (flip (by length sort Lst))))
(let Res
(mapcar
'((C)
(prog1 (or (find <> Lst... | Give a code snippet in #PicoLisp
Task
Shuffle the characters of a string in such a way that as many of the character values are in a different position as possible.
A shuffle that produces a randomized result among the best choices is to be preferred. A deterministic approach that produces the same sequence every ti... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_length | String length | Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme containing combining characters.
F... | #Lua | Lua | str = "Hello world"
length = #str | Give a code snippet in #Lua
Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme contai... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pythagorean_triples | Pythagorean triples | A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime,... | #Perl | Perl | sub gcd {
my ($n, $m) = @_;
while($n){
my $t = $n;
$n = $m % $n;
$m = $t;
}
return $m;
}
sub tripel {
my $pmax = shift;
my $prim = 0;
my $count = 0;
my $nmax = sqrt($pmax)/2;
for( my $n=1; $n<=$nmax; $n++ ) {
for( my $m=$n+1; (my $p = 2*$m*($m+$n))... | Give a code snippet in #Perl
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displ... | 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... | #AWK | AWK | # Find Mian-Chowla numbers: an
# where: ai = 1,
# and: an = smallest integer such that ai + aj is unique
# for all i, j in 1 .. n && i <= j
#
BEGIN \
{
FALSE = 0;
TRUE = 1;
mcCount = 1;
for( i = 1; mcC... | Give a code snippet in #AWK
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/Truncate_a_file | Truncate a file | Task
Truncate a file to a specific length. This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes).
Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating a temporary file of a reduced... | #Lua | Lua | function truncate (filename, length)
local inFile = io.open(filename, 'r')
if not inFile then
error("Specified filename does not exist")
end
local wholeFile = inFile:read("*all")
inFile:close()
if length >= wholeFile:len() then
error("Provided length is not less than current file... | Give a code snippet in #Lua
Task
Truncate a file to a specific length. This should be implemented as a routine that takes two parameters: the filename and the required file length (in bytes).
Truncation can be achieved using system or library calls intended for such a task, if such methods exist, or by creating ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cantor_set | Cantor set | Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| #D | D | import std.stdio;
enum WIDTH = 81;
enum HEIGHT = 5;
char[WIDTH*HEIGHT] lines;
void cantor(int start, int len, int index) {
int seg = len / 3;
if (seg == 0) return;
for (int i=index; i<HEIGHT; i++) {
for (int j=start+seg; j<start+seg*2; j++) {
int pos = i*WIDTH + j;
line... | Give a code snippet in #D
Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
⋮
⋮
⋮
⋱
... | #Visual_Basic | Visual Basic | Option Explicit
'------------
Public Function BuildIdentityMatrix(ByVal Size As Long) As Byte()
Dim i As Long
Dim b() As Byte
Size = Size - 1
ReDim b(0 To Size, 0 To Size)
'at this point, the matrix is allocated and
'all elements are initialized to 0 (zero)
For i = 0 To Size
b(i, i) = 1 'set diagonal ... | Give a code snippet in #Visual_Basic
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Generic_swap | Generic swap | Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides genericity.
If variables are typed in t... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
-- Simple values with no spaces can be swapped without the use of a parse template
lval = 27
rval = 5
say 'Before - <lval>'lval'</lval> <rval>'rval'</rval>'
parse (lval rval) rval lval
say 'After - <lval>'lval'</lval> <rval>'rva... | Give a code snippet in #NetRexx
Task
Write a generic swap function or operator which exchanges the values of two variables (or, more generally, any two storage places that can be assigned), regardless of their types.
If your solution language is statically typed please describe the way your language provides generic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evaluate_binomial_coefficients | Evaluate binomial coefficients | This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2
)
…
(
n
−
k
+
1
)
k
(
k
−
1... | #min | min | ((dup 0 ==) 'succ (dup pred) '* linrec) :fact
('dup dip dup ((fact) () (- fact) (fact * div)) spread) :binomial
5 3 binomial puts! | Give a code snippet in #min
This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/One-dimensional_cellular_automata | One-dimensional cellular automata | Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.
If, in the follow... | #PARI.2FGP | PARI/GP | step(v)=my(u=vector(#v),k);u[1]=v[1]&v[2];u[#u]=v[#v]&v[#v-1];for(i=2,#v-1,k=v[i-1]+v[i+1];u[i]=if(v[i],k==1,k==2));u; | Give a code snippet in #PARI.2FGP
Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the cur... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Balanced_brackets | Balanced brackets | Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nest.
Examples
(empty) ... | #11l | 11l | F gen(n)
V txt = [‘[’, ‘]’] * n
random:shuffle(&txt)
R txt.join(‘’)
F is_balanced(s)
V nesting_level = 0
L(c) s
S c
‘[’
nesting_level++
‘]’
I --nesting_level < 0
R 0B
R 1B
L(n) 0..9
V s = gen(n)
print(s‘’(‘ ’ * (20 - s.len))‘is ’... | Give a code snippet in #11l
Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nes... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game | 24 game | The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four digits, used exactly once each. T... | #Rust | Rust | use std::io::{self,BufRead};
extern crate rand;
use rand::Rng;
fn op_type(x: char) -> i32{
match x {
'-' | '+' => return 1,
'/' | '*' => return 2,
'(' | ')' => return -1,
_ => return 0,
}
}
fn to_rpn(input: &mut String){
let mut rpn_string : String = String::new();
... | Give a code snippet in #Rust
The 24 Game tests one's mental arithmetic.
Task
Write a program that randomly chooses and displays four digits, each from 1 ──► 9 (inclusive) with repetitions allowed.
The program should prompt for the player to enter an arithmetic expression using just those, and all of those four dig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #Mercury | Mercury | :- module sstack.
:- interface.
% We're going to call the type sstack (simple stack) because we don't want to get it
% accidentally confused with the official stack module in the standard library.
:- type sstack(T).
:- func sstack.new = sstack(T).
:- pred sstack.is_empty(sstack(T)::in) is semidet.
:- func sstack.... | Give a code snippet in #Mercury
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Galton_box_animation | Galton box animation | Example of a Galton Box at the end of animation.
A Galton device Sir Francis Galton's device is also known as a bean machine, a Galton Board, or a quincunx.
Description of operation
In a Galton box, there are a set of pins arranged in a triangular pattern. A number of balls are dropped so that ... | #Racket | Racket |
;a ball's position...row is a natural number and col is an integer where 0 is the center
(define-struct pos (row col))
;state of simulation...list of all positions and vector of balls (index = bin)
(define-struct st (poss bins))
;increment vector @i
(define (vector-inc! v i) (vector-set! v i (add1 (vector-ref v i))))... | Give a code snippet in #Racket
Example of a Galton Box at the end of animation.
A Galton device Sir Francis Galton's device is also known as a bean machine, a Galton Board, or a quincunx.
Description of operation
In a Galton box, there are a set of pins arranged in a triangular pattern. A numb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vampire_number | Vampire number | A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
together they consist of exactl... | #Go | Go | package main
import (
"fmt"
"math"
)
func max(a, b uint64) uint64 {
if a > b {
return a
}
return b
}
func min(a, b uint64) uint64 {
if a < b {
return a
}
return b
}
func ndigits(x uint64) (n int) {
for ; x > 0; x /= 10 {
n++
}
return
}
f... | Give a code snippet in #Go
A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
tog... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Letter_frequency | Letter frequency | Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequen... | #Julia | Julia | using DataStructures
function letterfreq(file::AbstractString; fltr::Function=(_) -> true)
sort(Dict(counter(filter(fltr, read(file, String)))))
end
display(letterfreq("src/Letter_frequency.jl"; fltr=isletter))
| Give a code snippet in #Julia
Task
Open a text file and count the occurrences of each letter.
Some of these programs count all characters (including punctuation),
but some only count letters A to Z.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (ass... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Plot_coordinate_pairs | Plot coordinate pairs | Task
Plot a function represented as x, y numerical arrays.
Post the resulting image for the following input arrays (taken from Python's Example section on Time a function):
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
y = {2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.... | #Maple | Maple | x := Vector([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]):
y := Vector([2.7, 2.8, 31.4, 38.1, 58.0, 76.2, 100.5, 130.0, 149.3, 180.0]):
plot(x,y,style="point"); | Give a code snippet in #Maple
Task
Plot a function represented as x, y numerical arrays.
Post the resulting image for the following input arrays (taken from Python's Example section on Time a function):
x = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
y = {2.7, 2.8, 31.4, 38.1,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pentomino_tiling | Pentomino tiling | A pentomino is a polyomino that consists of 5 squares. There are 12 pentomino shapes,
if you don't count rotations and reflections. Most pentominoes can form their own mirror image through
rotation, but some of them have to be flipped over.
I ... | #Kotlin | Kotlin | // Version 1.1.4-3
import java.util.Random
val F = arrayOf(
intArrayOf(1, -1, 1, 0, 1, 1, 2, 1), intArrayOf(0, 1, 1, -1, 1, 0, 2, 0),
intArrayOf(1, 0, 1, 1, 1, 2, 2, 1), intArrayOf(1, 0, 1, 1, 2, -1, 2, 0),
intArrayOf(1, -2, 1, -1, 1, 0, 2, -1), intArrayOf(0, 1, 1, 1, 1, 2, 2, 1),
intArrayOf(1, -1,... | Give a code snippet in #Kotlin
A pentomino is a polyomino that consists of 5 squares. There are 12 pentomino shapes,
if you don't count rotations and reflections. Most pentominoes can form their own mirror image through
rotation, but some of them have to be flipped over.
I ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Set | Set |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set creation
Test m ∈ S -- "m is an... | #OCaml | OCaml | # module IntSet = Set.Make(struct type t = int let compare = compare end);; (* Create a module for our type of set *)
module IntSet :
sig
type elt = int
type t
val empty : t
val is_empty : t -> bool
val mem : elt -> t -> bool
val add : elt -> t -> t
val singleton : elt -> t
val remove ... | Give a code snippet in #OCaml
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A set is a collection of elements, without duplicates and without order.
Task
Show each of these set operations:
Set c... | 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... | #Racket | Racket | #lang racket
(define (gamma number)
(if (> 1/2 number)
(/ pi (* (sin (* pi number))
(gamma (- 1.0 number))))
(let ((n (sub1 number))
(c '(0.99999999999980993 676.5203681218851 -1259.1392167224028
771.32342877765313 -176.61502916214059 12.507343278686905
... | Give a code snippet in #Racket
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/li... | 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... | #Python | Python | MASK64 = (1 << 64) - 1
C1 = 0x9e3779b97f4a7c15
C2 = 0xbf58476d1ce4e5b9
C3 = 0x94d049bb133111eb
class Splitmix64():
def __init__(self, seed=0):
self.state = seed & MASK64
def seed(self, num):
self.state = num & MASK64
def next_int(self):
"return random int between 0 and 2... | Give a code snippet in #Python
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/Discordian_date | Discordian date |
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| #PureBasic | PureBasic | Procedure.s Discordian_Date(Y, M, D)
Protected DoY=DayOfYear(Date(Y,M,D,0,0,0)), Yold$=Str(Y+1166)
Dim S.s(4)
S(0)="Chaos": S(1)="Discord": S(2)="Confusion": S(3)="Bureaucracy"
S(4)="The Aftermath"
If (Y%4=0 And Y%100) Or Y%400=0
If M=2 And D=29
ProcedureReturn "St. Tib's Day, YOLD " + Yold$
Els... | Give a code snippet in #PureBasic
Task
Convert a given date from the Gregorian calendar to the Discordian calendar.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Babbage_problem | Babbage problem |
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Computers, second edition, 1970, p.... | #PHP | PHP | <?php
for (
$i = 1 ; // Initial positive integer to check
($i * $i) % 1000000 !== 269696 ; // While i*i does not end with the digits 269,696
$i++ // ... go to next integer
);
echo $i, ' * ', $i, ' = ', ($i * $i), PHP_EO... | Give a code snippet in #PHP
Charles Babbage, looking ahead to the sorts of problems his Analytical Engine would be able to solve, gave this example:
What is the smallest positive integer whose square ends in the digits 269,696?
— Babbage, letter to Lord Bowden, 1837; see Hollingdale and Tootill, Electronic Comput... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #GML | GML | var doors,a,i;
//Sets up the array for all of the doors.
for (i = 1; i<=100; i += 1)
{
doors[i]=0;
}
//This first for loop goes through and passes the interval down to the next for loop.
for (i = 1; i <= 100; i += 1;)
{
//This for loop opens or closes the doors and uses the interval(if interval is... | Give a code snippet in #GML
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Permutations_by_swapping | Permutations by swapping | Task
Generate permutations of n items in which successive permutations differ from each other by the swapping of any two items.
Also generate the sign of the permutation which is +1 when the permutation is generated from an even number of swaps from the initial state, and -1 for odd.
Show the permutations and signs ... | #Raku | Raku | sub insert($x, @xs) { ([flat @xs[0 ..^ $_], $x, @xs[$_ .. *]] for 0 .. +@xs) }
sub order($sg, @xs) { $sg > 0 ?? @xs !! @xs.reverse }
multi perms([]) {
[] => +1
}
multi perms([$x, *@xs]) {
perms(@xs).map({ |order($_.value, insert($x, $_.key)) }) Z=> |(+1,-1) xx *
}
.say for perms([0..2]); | Give a code snippet in #Raku
Task
Generate permutations of n items in which successive permutations differ from each other by the swapping of any two items.
Also generate the sign of the permutation which is +1 when the permutation is generated from an even number of swaps from the initial state, and -1 for odd.
Sh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file | Create a file | In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Fortran | Fortran |
PROGRAM CREATION
OPEN (UNIT=5, FILE="output.txt", STATUS="NEW") ! Current directory
CLOSE (UNIT=5)
OPEN (UNIT=5, FILE="/output.txt", STATUS="NEW") ! Root directory
CLOSE (UNIT=5)
!Directories (Use System from GNU Fortran Compiler)
! -- Added by Anant Dixit, November 2014
call system("mkdir docs/")
call system("m... | Give a code snippet in #Fortran
In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix_multiplication | Matrix multiplication | Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| #Excel | Excel |
let MatrixMultiply (matrix1 : _[,] , matrix2 : _[,]) =
let result_row = (matrix1.GetLength 0)
let result_column = (matrix2.GetLength 1)
let ret = Array2D.create result_row result_column 0
for x in 0 .. result_row - 1 do
for y in 0 .. result_column - 1 do
let mutable acc = 0
... | Give a code snippet in #Excel
Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Convert_seconds_to_compound_duration | Convert seconds to compound duration | Task
Write a function or program which:
takes a positive integer representing a duration in seconds as input (e.g., 100), and
returns a string which shows the same duration decomposed into:
weeks,
days,
hours,
minutes, and
seconds.
This is detailed below (e.g., "2 hr, 59 sec").
Demonstrat... | #Fortran | Fortran |
SUBROUTINE PROUST(T) !Remembrance of time passed.
INTEGER T !The time, in seconds. Positive only, please.
INTEGER NTYPES !How many types of time?
PARAMETER (NTYPES = 5) !This should do.
INTEGER USIZE(NTYPES) !Size of the time unit.
CHARACTER*3 UNAME(NTYPES)!Name of the time ... | Give a code snippet in #Fortran
Task
Write a function or program which:
takes a positive integer representing a duration in seconds as input (e.g., 100), and
returns a string which shows the same duration decomposed into:
weeks,
days,
hours,
minutes, and
seconds.
This is detailed below (e.g... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_number_generator_(included) | Random number generator (included) | The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorithm used.
Note: the task is not t... | #MATLAB | MATLAB | setrand(3)
random(6)+1
\\ chosen by fair dice roll.
\\ guaranteed to the random. | Give a code snippet in #MATLAB
The task is to:
State the type of random number generator algorithm used in a language's built-in random number generator. If the language or its immediate libraries don't provide a random number generator, skip this task.
If possible, give a link to a wider explanation of the algorit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string | Tokenize a string | Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks related to string operations:
Me... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | StringJoin@StringSplit["Hello,How,Are,You,Today", "," -> "."] | Give a code snippet in #Mathematica.2FWolfram_Language
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing p... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Downward_for | Loops/Downward for | Task
Write a for loop which writes a countdown from 10 to 0.
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 body... | #Lua | Lua |
for i=10,0,-1 do
print(i)
end
| Give a code snippet in #Lua
Task
Write a for loop which writes a countdown from 10 to 0.
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/Incremen... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compound_data_type | Compound data type |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
Related task
Enumeration
S... | #Objeck | Objeck |
class Point {
@x : Int;
@y : Int;
New() {
@x := 0;
@y := 0;
}
New(x : Int, y : Int) {
@x := x;
@y := y;
}
New(p : Point) {
@x := p->GetX();
@y := p->GetY();
}
method : public : GetX() ~ Int {
return @x;
}
method : public : GetY() ~ Int {
return @y;... | Give a code snippet in #Objeck
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Task
Create a compound data type:
Point(x,y)
A compound data type is one that holds multiple independent values.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Caesar_cipher | Caesar cipher |
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A).
So key 2 encrypts "HI" to... | #Swift | Swift |
func usage(_ e:String) {
print("error: \(e)")
print("./caeser -e 19 a-secret-string")
print("./caeser -d 19 tskxvjxlskljafz")
}
func charIsValid(_ c:Character) -> Bool {
return c.isASCII && ( c.isLowercase || 45 == c.asciiValue ) // '-' = 45
}
func charRotate(_ c:Character, _ by:Int) -> Character {
var ... | Give a code snippet in #Swift
Task
Implement a Caesar cipher, both encoding and decoding.
The key is an integer from 1 to 25.
This cipher rotates (either towards left or right) the letters of the alphabet (A to Z).
The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_squares | Sum of squares | Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Function SumSquares(a() As Double) As Double
Dim As Integer length = UBound(a) - LBound(a) + 1
If length = 0 Then Return 0.0
Dim As Double sum = 0.0
For i As Integer = LBound(a) To UBound(a)
sum += a(i) * a(i)
Next
Return sum
End Function
Dim a(5) As Double = {1.0, 2.0, 3.0, -1.0, ... | Give a code snippet in #FreeBASIC
Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #SenseTalk | SenseTalk |
set keyList to ["red", "green", "blue"]
set valueList to [150,0,128]
repeat with n=1 to the number of items in keyList
set map.(item n of keyList) to item n of valueList
end repeat
put map
--> (blue:"128", green:"0", red:"150")
| Give a code snippet in #SenseTalk
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #FutureBasic | FutureBasic | window 1, @"Greatest Common Divisor", (0,0,480,270)
local fn gcd( a as short, b as short ) as short
short result
if ( b != 0 )
result = fn gcd( b, a mod b)
else
result = abs(a)
end if
end fn = result
print fn gcd( 6, 9 )
HandleEvents | Give a code snippet in #FutureBasic
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 gr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort_with_shifting_bounds | Sorting algorithms/Cocktail sort with shifting bounds |
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
... | #VBScript | VBScript | ' Sorting algorithms/Cocktail sort with shifting bounds - VBScript
Function cocktailShakerSort(ByVal A)
beginIdx = Lbound(A)
endIdx = Ubound(A)-1
Do While beginIdx <= endIdx
newBeginIdx = endIdx
newEndIdx = beginIdx
For ii = beginIdx To endIdx
If A(ii) > A(ii+1) Then
... | Give a code snippet in #VBScript
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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
... | #Common_Lisp | Common Lisp | (remove-duplicates '(1 3 2 9 1 2 3 8 8 1 0 2))
> (9 3 8 1 0 2) | Give a code snippet in #Common_Lisp
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 |
Qu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mean_angle | Averages/Mean angle | When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first reading was of 350 degrees and the ... | #Stata | Stata | mata
function meanangle(a) {
return(arg(sum(exp(C(0,a)))))
}
deg=pi()/180
meanangle((350,10)*deg)/deg
-1.61481e-15
meanangle((90,180,270,360)*deg)/deg
0
meanangle((10,20,30)*deg)/deg
20
end | Give a code snippet in #Stata
When calculating the average or mean of an angle one has to take into account how angles wrap around so that any angle in degrees plus any integer multiple of 360 degrees is a measure of the same angle.
If one wanted an average direction of the wind over two readings where the first read... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_a_set_of_characters_from_a_string | Strip a set of characters from a string | Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any characters in the second argument:
print str... | #Burlesque | Burlesque |
blsq ) "She was a soul stripper. She took my heart!"{"aei"\/~[n!}f[
"Sh ws soul strppr. Sh took my hrt!"
| Give a code snippet in #Burlesque
Task
Create a function that strips a set of characters from a string.
The function should take two arguments:
a string to be stripped
a string containing the set of characters to be stripped
The returned string should contain the first string, stripped of any characters ... | 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... | #D | D | import std.stdio, std.string;
void main() {
immutable mnOrig = 1, mxOrig = 10;
int mn = mnOrig, mx = mxOrig;
writefln(
"Think of a number between %d and %d 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... | Give a code snippet in #D
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 comp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CSV_to_HTML_translation | CSV to HTML translation | Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Task
Create a function that takes a st... | #UNIX_Shell | UNIX Shell | csv2html() {
IFS=,
echo "<table>"
echo "<thead>"
read -a fields
htmlrow th "${fields[@]}"
echo "</thead>"
echo "<tbody>"
while read -a fields
do htmlrow td "${fields[@]}"
done
echo "</tbody>"
echo "</table>"
}
htmlrow() {
cell=$1
shift
echo "<tr>"
for field
... | Give a code snippet in #UNIX_Shell
Consider a simplified CSV format where all rows are separated by a newline
and all columns are separated by commas.
No commas are allowed as field data, but the data may contain
other characters and character sequences that would
normally be escaped when converted to HTML
Tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hash_from_two_arrays | Hash from two arrays | Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| #Bracmat | Bracmat | two three apple:?arr1
& 2 3 fruit:?arr2
& new$hash:?H
& whl
' ( !arr1:%?k ?arr1
& !arr2:%?v ?arr2
& (H..insert)$(!k.!v)
)
& (H..forall)$out
& ;
| Give a code snippet in #Bracmat
Task
Using two Arrays of equal length, create a Hash object
where the elements from one array (the keys) are linked
to the elements of the other (the values)
Related task
Associative arrays/Creation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Lambdatalk | Lambdatalk |
{span {@ style="text-transform:lowercase"} alphaBETA } -> alphabeta
{span {@ style="text-transform:uppercase"} alphaBETA } -> ALPHABETA
| Give a code snippet in #Lambdatalk
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 ... | christopher/rosetta-code |
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