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/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 ... | #SPL | SPL | d='JC5wcmludCgiZD0nIitkKyInOyIrJC5iNjRkZWNvZGUoZCkp';$.print("d='"+d+"';"+$.b64decode(d))
| Give a code snippet in #SPL
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
s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Chaocipher | Chaocipher | Description
The Chaocipher was invented by J.F.Byrne in 1918 and, although simple by modern cryptographic standards, does not appear to have been broken until the algorithm was finally disclosed by his family in 2010.
The algorithm is described in this paper by M.Rubin in 2010 and there is a C# implementation here.
... | #Objeck | Objeck | class Chaocipher {
L_ALPHABET : static : Char[];
R_ALPHABET : static : Char[];
function : Main(args : String[]) ~ Nil {
L_ALPHABET := "HXUCZVAMDSLKPEFJRIGTWOBNYQ"->ToCharArray();
R_ALPHABET := "PTLNBQDEOYSFAVZKGJRIHWXUMC"->ToCharArray();
plainText := "WELLDONEISBETTERTHANWELLSAID"->ToCharArray();
... | Give a code snippet in #Objeck
Description
The Chaocipher was invented by J.F.Byrne in 1918 and, although simple by modern cryptographic standards, does not appear to have been broken until the algorithm was finally disclosed by his family in 2010.
The algorithm is described in this paper by M.Rubin in 2010 and ther... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Partial_function_application | Partial function application | Partial function application is the ability to take a function of many
parameters and apply arguments to some of the parameters to create a new
function that needs only the application of the remaining arguments to
produce the equivalent of applying all arguments to the original function.
E.g:
Given values v1, v2
... | #Racket | Racket |
#lang racket
(define (fs f s) (map f s))
(define (f1 n) (* n 2))
(define (f2 n) (* n n))
(define fsf1 (curry fs f1))
(define fsf2 (curry fs f2))
(fsf1 '(0 1 2 3))
(fsf1 '(2 4 6 8))
(fsf2 '(0 1 2 3))
(fsf2 '(2 4 6 8))
| Give a code snippet in #Racket
Partial function application is the ability to take a function of many
parameters and apply arguments to some of the parameters to create a new
function that needs only the application of the remaining arguments to
produce the equivalent of applying all arguments to the original functi... | 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... | #Mercury | Mercury | :- module string_byte_length.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is det.
:- implementation.
:- import_module list, string.
main(!IO) :-
Words = ["møøse", "𝔘𝔫𝔦𝔠𝔬𝔡𝔢", "J\x332\o\x332\s\x332\e\x301\\x332\"],
io.write_list(Words, "", write_length, !IO).
:- pred write_l... | Give a code snippet in #Mercury
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 co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #PHP | PHP | function mergesort($arr){
if(count($arr) == 1 ) return $arr;
$mid = count($arr) / 2;
$left = array_slice($arr, 0, $mid);
$right = array_slice($arr, $mid);
$left = mergesort($left);
$right = mergesort($right);
return merge($left, $right);
}
function merge($left, $right){
$res = array();
while (count($le... | Give a code snippet in #PHP
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/Find_the_missing_permutation | Find the missing permutation | ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
CDBA
... | #Delphi | Delphi |
;; use the obvious methos
(lib 'list) ; for (permutations) function
;; input
(define perms '
(ABCD CABD ACDB DACB BCDA ACBD ADCB CDAB DABC BCAD CADB CDBA CBAD ABDC ADBC BDCA DCBA BACD BADC BDAC CBDA DBCA DCAB))
;; generate all permutations
(define all-perms (map list->string (permutations '(A B C D))))
→ all-p... | Give a code snippet in #Delphi
ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
... | 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... | #PowerShell | PowerShell |
function When-Condition
{
[CmdletBinding()]
Param
(
[Parameter(Mandatory=$true, Position=0)]
[bool]
$Test1,
[Parameter(Mandatory=$true, Position=1)]
[bool]
$Test2,
[Parameter(Mandatory=$true, Position=2)]
[scriptblock]
$Both,
... | Give a code snippet in #PowerShell
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Binary_search | Binary search | A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a secret number, and will only tell the p... | #uBasic.2F4tH | uBasic/4tH | For i = 1 To 100 ' Fill array with some values
@(i-1) = i
Next
Print FUNC(_binarySearch(50,0,99)) ' Now find value '50'
End ' and prints its index
_binarySearch Param(3) ' value, start index, end index
Local(1) ... | Give a code snippet in #uBasic.2F4tH
A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roman_numerals/Encode | Roman numerals/Encode | Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value of zero.
In Roman numeral... | #SPL | SPL | a2r(a)=
r = ""
n = [["M","CM","D","CD","C","XC","L","XL","X","IX","V","IV","I"],[1000,900,500,400,100,90,50,40,10,9,5,4,1]]
> i, 1..13
> a!<n[i,2]
r += n[i,1]
a -= n[i,2]
<
<
<= r
.
t = [1990,2008,1666]
> i, 1..#.size(t,1)
#.output(t[i]," = ",a2r(t[i]))
< | Give a code snippet in #SPL
Task
Create a function taking a positive integer as its parameter and returning a string containing the Roman numeral representation of that integer. Modern Roman numerals are written by expressing each digit separately, starting with the left most digit and skipping any digit with a value... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_sentence_from_book | Random sentence from book | Read in the book "The War of the Worlds", by H. G. Wells.
Skip to the start of the book, proper.
Remove extraneous punctuation, but keep at least sentence-ending punctuation characters . ! and ?
Keep account of what words follow words and how many times it is seen, (treat sentence terminators as words too).
Keep a... | #Python | Python | from urllib.request import urlopen
import re
from string import punctuation
from collections import Counter, defaultdict
import random
# The War of the Worlds, by H. G. Wells
text_url = 'http://www.gutenberg.org/files/36/36-0.txt'
text_start = 'No one would have believed'
sentence_ending = '.!?'
sentence_pausing ... | Give a code snippet in #Python
Read in the book "The War of the Worlds", by H. G. Wells.
Skip to the start of the book, proper.
Remove extraneous punctuation, but keep at least sentence-ending punctuation characters . ! and ?
Keep account of what words follow words and how many times it is seen, (treat sentence te... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Safe_addition | Safe addition | Implementation of interval arithmetic and more generally fuzzy number arithmetic require operations that yield safe upper and lower bounds of the exact result.
For example, for an addition, it is the operations +↑ and +↓ defined as: a +↓ b ≤ a + b ≤ a +↑ b.
Additionally it is desired that the widt... | #Forth | Forth | c-library m
s" m" add-lib
\c #include <math.h>
c-function fnextafter nextafter r r -- r
end-c-library
s" MAX-FLOAT" environment? drop fconstant MAX-FLOAT
: fstepdown ( F: r1 -- r2 )
MAX-FLOAT fnegate fnextafter ;
: fstepup ( F: r1 -- r2 )
MAX-FLOAT fnextafter ;
: savef+ ( F: r1 r2 -- r3 r4 ) \ r4 <= r1+r2 <... | Give a code snippet in #Forth
Implementation of interval arithmetic and more generally fuzzy number arithmetic require operations that yield safe upper and lower bounds of the exact result.
For example, for an addition, it is the operations +↑ and +↓ defined as: a +↓ b ≤ a + b ≤ a +↑ b.
Additiona... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Apply_a_callback_to_an_array | Apply a callback to an array | Task
Take a combined set of elements and apply a function to each element.
| #MATLAB | MATLAB | >> array = [1 2 3 4 5]
array =
1 2 3 4 5
>> arrayfun(@sin,array)
ans =
Columns 1 through 4
0.841470984807897 0.909297426825682 0.141120008059867 -0.756802495307928
Column 5
-0.958924274663138
>> cellarray = {1,2,3,4,5}
cellarray =
[1] [2] [3] [4] ... | Give a code snippet in #MATLAB
Task
Take a combined set of elements and apply a function to each element.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #Brat | Brat | number = random 10
p "Guess a number between 1 and 10."
until {
true? ask("Guess: ").to_i == number
{ p "Well guessed!"; true }
{ p "Guess again!" }
} | Give a code snippet in #Brat
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/XML/XPath | XML/XPath | Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniCorp Store #45x10^3">
<section name="heal... | #AutoHotkey | AutoHotkey | FileRead, inventory, xmlfile.xml
RegExMatch(inventory, "<item.*?</item>", item1)
MsgBox % item1
pos = 1
While, pos := RegExMatch(inventory, "<price>(.*?)</price>", price, pos + 1)
MsgBox % price1
While, pos := RegExMatch(inventory, "<name>.*?</name>", name, pos + 1)
names .= name . "`n"
MsgBox % names | Give a code snippet in #AutoHotkey
Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniCorp St... | 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
... | #Logo | Logo | print reverse "cat ; tac | Give a code snippet in #Logo
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Closures/Value_capture | Closures/Value capture | Task
Create a list of ten functions, in the simplest manner possible (anonymous functions are encouraged), such that the function at index i (you may choose to start i from either 0 or 1), when run, should return the square of the index, that is, i 2.
Display the result of runnin... | #Yabasic | Yabasic |
dim funcs$(10)
sub power2(i)
return i * i
end sub
for i = 1 to 10
funcs$(i) = "power2"
next
for i = 1 to 10
print execute(funcs$(i), i)
next
| Give a code snippet in #Yabasic
Task
Create a list of ten functions, in the simplest manner possible (anonymous functions are encouraged), such that the function at index i (you may choose to start i from either 0 or 1), when run, should return the square of the index, that is, i ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_to_Windows_event_log | Write to Windows event log | Task
Write script status to the Windows Event Log
| #Ruby | Ruby | require 'win32/eventlog'
logger = Win32::EventLog.new
logger.report_event(:event_type => Win32::EventLog::INFO, :data => "a test event log entry") | Give a code snippet in #Ruby
Task
Write script status to the Windows Event Log
| 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... | #Picat | Picat | go =>
["1223334444",
"Rosetta Code is the best site in the world!",
"1234567890abcdefghijklmnopqrstuvwxyz",
"Picat is fun"].map(entropy).println(),
nl.
% probabilities of each element/character in L
entropy(L) = Entropy =>
Len = L.length,
Occ = new_map(), % # of occurrences
foreach(E in L)
Occ... | Give a code snippet in #Picat
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/Memory_allocation | Memory allocation | Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| #Lingo | Lingo | -- Create a ByteArray of 100 Kb (pre-filled with 0 bytes)
ba = byteArray(102400)
-- Lingo uses garbage-collection, so allocated memory is released when no more references exist.
-- For the above variable ba, this can be achieved by calling:
ba = VOID | Give a code snippet in #Lingo
Task
Show how to explicitly allocate and deallocate blocks of memory in your language.
Show access to different types of memory (i.e., heap, stack, shared, foreign) if applicable.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Optional_parameters | Optional parameters | Task
Define a function/method/subroutine which sorts a sequence ("table") of sequences ("rows") of strings ("cells"), by one of the strings. Besides the input to be sorted, it shall have the following optional parameters:
ordering
A function specifying the ordering of strings; lexicographic by default.
column
... | #D | D | import std.stdio, std.algorithm, std.functional;
string[][] sortTable(string[][] table,
in bool function(string[],string[]) ordering=null,
in int column = 0,
in bool reverse = false) {
if (ordering is null)
table.schwartzSort!(row => row[colum... | Give a code snippet in #D
Task
Define a function/method/subroutine which sorts a sequence ("table") of sequences ("rows") of strings ("cells"), by one of the strings. Besides the input to be sorted, it shall have the following optional parameters:
ordering
A function specifying the ordering of strings; lexicog... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Haversine_formula | Haversine formula |
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
The haversine formula is an equation important in navigation, g... | #Java | Java | public class Haversine {
public static final double R = 6372.8; // In kilometers
public static double haversine(double lat1, double lon1, double lat2, double lon2) {
double dLat = Math.toRadians(lat2 - lat1);
double dLon = Math.toRadians(lon2 - lon1);
lat1 = Math.toRadians(lat1);
... | Give a code snippet in #Java
This page uses content from Wikipedia. The original article was at Haversine formula. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
The haversine formula is an equat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dining_philosophers | Dining philosophers | The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and eating spaghetti. They eat at a rou... | #PureBasic | PureBasic | Macro Tell(Mutex, Message) ; Make a macro to easy send info back to main thread
LockMutex(Mutex)
LastElement(Queue())
AddElement(Queue())
Queue() = Message
SignalSemaphore(Semaphore)
UnlockMutex(Mutex)
EndMacro
;Set up a data structure to pass needed info into the threads
Structure Thread_Paramete... | Give a code snippet in #PureBasic
The dining philosophers problem illustrates non-composability of low-level synchronization primitives like semaphores. It is a modification of a problem posed by Edsger Dijkstra.
Five philosophers, Aristotle, Kant, Spinoza, Marx, and Russell (the tasks) spend their time thinking and ... | 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... | #Oforth | Oforth | Channel new [ ] over send drop const: StdValues
: stddev(x)
| l |
StdValues receive x + dup ->l StdValues send drop
#qs l map sum l size asFloat / l avg sq - sqrt ; | Give a code snippet in #Oforth
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 func... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Case-sensitivity_of_identifiers | Case-sensitivity of identifiers | Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, Samba and Bernie.
For a language... | #DWScript | DWScript |
var dog : String;
dog := 'Benjamin';
Dog := 'Samba';
DOG := 'Bernie';
PrintLn('There is just one dog named ' + dog); | Give a code snippet in #DWScript
Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Semordnilap | Semordnilap | A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the total number of unique semordnilap ... | #Scala | Scala | val wordsAll =
scala.io.Source.
fromURL("http://wiki.puzzlers.org/pub/wordlists/unixdict.txt").
getLines().map(_.toLowerCase).toIndexedSeq
/**
* Given a sequence of lower-case words return a sub-sequence
* of matches containing the word and its reverse if the two
* words are different.
*/
def semordn... | Give a code snippet in #Scala
A semordnilap is a word (or phrase) that spells a different word (or phrase) backward. "Semordnilap" is a word that itself is a semordnilap.
Example: lager and regal
Task
This task does not consider semordnilap phrases, only single words.
Using only words from this list, report the tota... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Enforced_immutability | Enforced immutability | Task
Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
| #Bracmat | Bracmat | myVar=immutable (m=mutable) immutable;
changed:?(myVar.m);
lst$myVar
| Give a code snippet in #Bracmat
Task
Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Modified_random_distribution | Modified random distribution | Given a random number generator, (rng), generating numbers in the range 0.0 .. 1.0 called rgen, for example; and a function modifier(x)
taking an number in the same range and generating the probability that the input should be generated, in the same range 0..1; then implement the following algorithm for generating rand... | #Go | Go | package main
import (
"fmt"
"math"
"math/rand"
"strings"
"time"
)
func rng(modifier func(x float64) float64) float64 {
for {
r1 := rand.Float64()
r2 := rand.Float64()
if r2 < modifier(r1) {
return r1
}
}
}
func commatize(n int) string {
s... | Give a code snippet in #Go
Given a random number generator, (rng), generating numbers in the range 0.0 .. 1.0 called rgen, for example; and a function modifier(x)
taking an number in the same range and generating the probability that the input should be generated, in the same range 0..1; then implement the following a... | 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... | #Objeck | Objeck | use Collection.Generic;
use System.Matrix;
class RPNParser {
@stk : Stack<IntHolder>;
@digits : List<IntHolder>;
function : Main(args : String[]) ~ Nil {
digits := List->New()<IntHolder>;
"Make 24 with the digits: "->Print();
for(i := 0; i < 4; i += 1;) {
n : Int := Int->Random(1, 9);
... | Give a code snippet in #Objeck
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 d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_digits_of_an_integer | Sum digits of an integer | Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| #Haskell | Haskell | digsum
:: Integral a
=> a -> a -> a
digsum base = f 0
where
f a 0 = a
f a n = f (a + r) q
where
(q, r) = n `quotRem` base
main :: IO ()
main = print $ digsum 16 255 -- "FF": 15 + 15 = 30 | Give a code snippet in #Haskell
Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Conditional_structures | Conditional structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common conditional structures include ... | #Trith | Trith | true ["yes" print] ["no" print] branch | Give a code snippet in #Trith
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/UTF-8_encode_and_decode | UTF-8 encode and decode | As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the... | #Tcl | Tcl | proc encoder int {
set u [format %c $int]
set bytes {}
foreach byte [split [encoding convertto utf-8 $u] ""] {
lappend bytes [format %02X [scan $byte %c]]
}
return $bytes
}
proc decoder bytes {
set str {}
foreach byte $bytes {
append str [format %c [scan $byte %x]]
}
return [encod... | Give a code snippet in #Tcl
As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes repre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/Unbounded | Knapsack problem/Unbounded | A traveler gets diverted and has to make an unscheduled stop in what turns out to be Shangri La. Opting to leave, he is allowed to take as much as he likes of the following items, so long as it will fit in his knapsack, and he can carry it.
He knows that he can carry no more than 25 'weights' in total; and tha... | #Prolog | Prolog | :- use_module(library(simplex)).
% tuples (name, Explantion, Value, weights, volume).
knapsack :-
L =[( panacea, 'Incredible healing properties', 3000, 0.3, 0.025),
( ichor, 'Vampires blood', 1800, 0.2, 0.015),
( gold , 'Shiney shiney', 2500, 2.0, 0.002)],
gen_state(S0),
l... | Give a code snippet in #Prolog
A traveler gets diverted and has to make an unscheduled stop in what turns out to be Shangri La. Opting to leave, he is allowed to take as much as he likes of the following items, so long as it will fit in his knapsack, and he can carry it.
He knows that he can carry no more than 25... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_string | Empty string | Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other tasks related to string oper... | #zkl | zkl | s:=""; // or s:=String, String is the object ""
s.toBool() //-->False
if (s) println("not empty") | Give a code snippet in #zkl
Languages may have features for dealing specifically with empty strings
(those containing no characters).
Task
Demonstrate how to assign an empty string to a variable.
Demonstrate how to check that a string is empty.
Demonstrate how to check that a string is not empty.
Other... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mayan_calendar | Mayan calendar | The ancient Maya people had two somewhat distinct calendar systems.
In somewhat simplified terms, one is a cyclical calendar known as The Calendar Round,
that meshes several sacred and civil cycles; the other is an offset calendar
known as The Long Count, similar in many ways to the Gregorian calendar.
The Calendar R... | #zkl | zkl | var [const]
sacred=T("Imix'","Ik'","Ak'bal","K'an","Chikchan","Kimi","Manik'","Lamat","Muluk","Ok",
"Chuwen","Eb","Ben","Hix","Men","K'ib'","Kaban","Etz'nab'","Kawak","Ajaw"),
civil=T("Pop","Wo'","Sip","Sotz'","Sek","Xul","Yaxk'in","Mol","Ch'en","Yax","Sak'","Keh",
"Mak","K'ank'in","Muwan'","P... | Give a code snippet in #zkl
The ancient Maya people had two somewhat distinct calendar systems.
In somewhat simplified terms, one is a cyclical calendar known as The Calendar Round,
that meshes several sacred and civil cycles; the other is an offset calendar
known as The Long Count, similar in many ways to the Gregor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fraction_reduction | Fraction reduction | There is a fine line between numerator and denominator. ─── anonymous
A method to "reduce" some reducible fractions is to cross out a digit from the
numerator and the denominator. An example is:
16 16
──── and then (simp... | #MiniZinc | MiniZinc |
%Fraction Reduction. Nigel Galloway, September 5th., 2019
include "alldifferent.mzn"; include "member.mzn";
int: S;
array [1..9] of int: Pn=[1,10,100,1000,10000,100000,1000000,10000000,100000000];
array [1..S] of var 1..9: Nz; constraint alldifferent(Nz);
array [1..S] of var 1..9: Gz; constraint alldifferent(Gz);
var... | Give a code snippet in #MiniZinc
There is a fine line between numerator and denominator. ─── anonymous
A method to "reduce" some reducible fractions is to cross out a digit from the
numerator and the denominator. An example is:
16 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Undefined_values | Undefined values | #Delphi | Delphi | var
P: PInteger;
begin
New(P); //Allocate some memory
try
If Assigned(P) Then //...
begin
P^ := 42;
end;
finally
Dispose(P); //Release memory allocated by New
end;
end; | Give a code snippet in #Delphi
| 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... | #OCaml | OCaml | let a = (3.0, 4.0, 5.0)
let b = (4.0, 3.0, 5.0)
let c = (-5.0, -12.0, -13.0)
let string_of_vector (x,y,z) =
Printf.sprintf "(%g, %g, %g)" x y z
let dot (a1, a2, a3) (b1, b2, b3) =
(a1 *. b1) +. (a2 *. b2) +. (a3 *. b3)
let cross (a1, a2, a3) (b1, b2, b3) =
(a2 *. b3 -. a3 *. b2,
a3 *. b1 -. a1 *. b3,
... | Give a code snippet in #OCaml
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 nu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Constrained_genericity | Constrained genericity | Constrained genericity or bounded quantification means
that a parametrized type or function (see parametric polymorphism)
can only be instantiated on types fulfilling some conditions,
even if those conditions are not used in that function.
Say a type is called "eatable" if you can call the function eat on it.
Write a ... | #Sather | Sather | abstract class $EDIBLE is
eat;
end;
class FOOD < $EDIBLE is
readonly attr name:STR;
eat is
#OUT + "eating " + self.name + "\n";
end;
create(name:STR):SAME is
res ::= new;
res.name := name;
return res;
end;
end;
class CAR is
readonly attr name:STR;
create(name:STR):SAME is
res ::=... | Give a code snippet in #Sather
Constrained genericity or bounded quantification means
that a parametrized type or function (see parametric polymorphism)
can only be instantiated on types fulfilling some conditions,
even if those conditions are not used in that function.
Say a type is called "eatable" if you can call ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_HQ9%2B | Execute HQ9+ | Task
Implement a HQ9+ interpreter or compiler.
| #Action.21 | Action! | PROC Run(CHAR ARRAY code)
BYTE i,a
CHAR c
PrintF("Run ""%S""%E%E",code)
a=0
FOR i=1 TO code(0)
DO
c=code(i)
IF c='q OR c='Q THEN
PrintE(code)
ELSEIF c='h OR c='H THEN
PrintE("Hello, world!")
ELSEIF c='9 THEN
PrintE("99 bottles here...")
ELSEIF c='+ THEN
a==+1
... | Give a code snippet in #Action.21
Task
Implement a HQ9+ interpreter or compiler.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Chinese_zodiac | Chinese zodiac | Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities results in the well-known "Chinese zo... | #Sidef | Sidef | func zodiac(year) {
var animals = %w(Rat Ox Tiger Rabbit Dragon Snake Horse Goat Monkey Rooster Dog Pig)
var elements = %w(Wood Fire Earth Metal Water)
var terrestrial_han = %w(子 丑 寅 卯 辰 巳 午 未 申 酉 戌 亥)
var terrestrial_pinyin = %w(zĭ chŏu yín măo chén sì wŭ wèi shēn yŏu xū hài)
var celestial_han = %w(甲 乙 丙 丁 戊... | Give a code snippet in #Sidef
Traditionally, the Chinese have counted years using two simultaneous cycles, one of length 10 (the "celestial stems") and one of length 12 (the "terrestrial branches"); the combination results in a repeating 60-year pattern. Mapping the branches to twelve traditional animal deities result... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping | Tokenize a string with escaping | Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for splitting:
The fields that were s... | #C.23 | C# | using System;
using System.Text;
using System.Collections.Generic;
public class TokenizeAStringWithEscaping
{
public static void Main() {
string testcase = "one^|uno||three^^^^|four^^^|^cuatro|";
foreach (var token in testcase.Tokenize(separator: '|', escape: '^')) {
Console.WriteLine(... | Give a code snippet in #C.23
Task[edit]
Write a function or program that can split a string at each non-escaped occurrence of a separator character.
It should accept three input parameters:
The string
The separator character
The escape character
It should output a list of strings.
Details
Rules for split... | 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... | #CLU | CLU | % Split a string based on a change of character
split_on_change = iter (s: string) yields (string)
part: string := ""
for c: char in string$chars(s) do
if ~string$empty(part)
cand part[string$size(part)] ~= c then
yield(part)
part := ""
end
part := part ... | Give a code snippet in #CLU
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_totient_numbers | Perfect totient numbers | Generate and show here, the first twenty Perfect totient numbers.
Related task
Totient function
Also see
the OEIS entry for perfect totient numbers.
mrob list of the first 54
| #Julia | Julia | using Primes
eulerphi(n) = (r = one(n); for (p,k) in factor(abs(n)) r *= p^(k-1)*(p-1) end; r)
const phicache = Dict{Int, Int}()
cachedphi(n) = (if !haskey(phicache, n) phicache[n] = eulerphi(n) end; phicache[n])
function perfecttotientseries(n)
perfect = Vector{Int}()
i = 1
while length(perfect) < ... | Give a code snippet in #Julia
Generate and show here, the first twenty Perfect totient numbers.
Related task
Totient function
Also see
the OEIS entry for perfect totient numbers.
mrob list of the first 54
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_Brain**** | Execute Brain**** | Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly implement the following instructions:... | #Clojure | Clojure | (ns brainfuck)
(def ^:dynamic *input*)
(def ^:dynamic *output*)
(defrecord Data [ptr cells])
(defn inc-ptr [next-cmd]
(fn [data]
(next-cmd (update-in data [:ptr] inc))))
(defn dec-ptr [next-cmd]
(fn [data]
(next-cmd (update-in data [:ptr] dec))))
(defn inc-cell [next-cmd]
(fn [data]
(next-... | Give a code snippet in #Clojure
Execute Brain**** is an implementation of Brainf***.
Other implementations of Brainf***.
RCBF is a set of Brainf*** compilers and interpreters written for Rosetta Code in a variety of languages.
Below are links to each of the versions of RCBF.
An implementation need only properly impl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mutual_recursion | Mutual recursion | Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
)
=
n
−
M
(
F
(
n
−
1
)
)
,
... | #Jsish | Jsish | /* Mutual recursion, is jsish */
function f(num):number { return (num === 0) ? 1 : num - m(f(num - 1)); }
function m(num):number { return (num === 0) ? 0 : num - f(m(num - 1)); }
function range(n=10, start=0, step=1):array {
var a = Array(n).fill(0);
for (var i in a) a[i] = start+i*step;
return a;
}
var a ... | Give a code snippet in #Jsish
Two functions are said to be mutually recursive if the first calls the second,
and in turn the second calls the first.
Write two mutually recursive functions that compute members of the Hofstadter Female and Male sequences defined as:
F
(
0
)
=
1
;
M
(
0
)
=
0
F
(
n
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_common_subsequence | Longest common subsequence | Introduction
Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string.
The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings.
Let A ≡ A[0]… A[m - 1] and B ≡ B[0]… B[n - 1], m < n be strings drawn from an alphabet Σ of ... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | a = "thisisatest";
b = "testing123testing";
LongestCommonSequence[a, b] | Give a code snippet in #Mathematica.2FWolfram_Language
Introduction
Define a subsequence to be any output string obtained by deleting zero or more symbols from an input string.
The Longest Common Subsequence (LCS) is a subsequence of maximum length common to two or more strings.
Let A ≡ A[0]… A[m - 1] and B ≡ B[0]…... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Infinity | Infinity | Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherwise, return the largest possible po... | #Tcl | Tcl | package require Tcl 8.5
expr {1.0 / 0} ;# ==> Inf
expr {-1.0 / 0} ;# ==> -Inf
expr {inf} ;# ==> Inf
expr {1 / 0} ;# ==> "divide by zero" error; Inf not part of range of integer division | Give a code snippet in #Tcl
Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherwise, r... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Comb_sort | Sorting algorithms/Comb sort | Sorting algorithms/Comb sort
You are encouraged to solve this task according to the task description, using any language you may know.
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 algor... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref savelog symbols binary
placesList = [String -
"UK London", "US New York" -
, "US Boston", "US Washington" -
, "UK Washington", "US Birmingham" -
, "UK Birmingham", "UK Boston" -
]
sortedList = combSort(String[] Arrays.copyOf... | Give a code snippet in #NetRexx
Sorting algorithms/Comb sort
You are encouraged to solve this task according to the task description, using any language you may know.
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Send_an_unknown_method_call | Send an unknown method call | Task
Invoke an object method where the name of the method to be invoked can be generated at run time.
Related tasks
Respond to an unknown method call.
Runtime evaluation
| #PowerShell | PowerShell |
$method = ([Math] | Get-Member -MemberType Method -Static | Where-Object {$_.Definition.Split(',').Count -eq 1} | Get-Random).Name
$number = (1..9 | Get-Random) / 10
$result = [Math]::$method($number)
$output = [PSCustomObject]@{
Method = $method
Number = $number
Result = $result
}
$output | Format-List... | Give a code snippet in #PowerShell
Task
Invoke an object method where the name of the method to be invoked can be generated at run time.
Related tasks
Respond to an unknown method call.
Runtime evaluation
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Brownian_tree | Brownian tree | Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initial "seed" is placed somewhere wi... | #J | J | brtr=:4 :0
seed=. ?x
clip=. 0 >. (<:x) <."1 ]
near=. [: clip +"1/&(,"0/~i:1)
p=.i.0 2
mask=. 1 (<"1 near seed)} x$0
field=.1 (<seed)} x$0
for.i.y do.
p=. clip (p +"1 <:?3$~$p),?x
b=.(<"1 p) { mask
fix=. b#p
if.#fix do. NB. if. works around j602 bug: 0(0#a:)}i.0 0
p=. (-.b)# p
m... | Give a code snippet in #J
Brownian tree
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate and draw a Brownian Tree.
A Brownian Tree is generated as a result of an initial seed, followed by the interaction of two processes.
The initial "s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #Wolfram_Language | Wolfram Language | Print["Hello world!"] | Give a code snippet in #Wolfram_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/Stand... | christopher/rosetta-code | |
http://rosettacode.org/wiki/HTTPS | HTTPS | Task
Send a GET request to obtain the resource located at the URL "https://www.w3.org/", then print it to the console.
Checking the host certificate for validity is recommended.
Do not authenticate. That is the subject of other tasks.
Readers may wish to contrast with the HTTP Request task, and also the task on HTT... | #AutoHotkey | AutoHotkey |
URL := "https://sourceforge.net/"
WININET_Init()
msgbox % html := UrlGetContents(URL)
WININET_UnInit()
return
#include urlgetcontents.ahk
#include wininet.ahk
| Give a code snippet in #AutoHotkey
Task
Send a GET request to obtain the resource located at the URL "https://www.w3.org/", then print it to the console.
Checking the host certificate for validity is recommended.
Do not authenticate. That is the subject of other tasks.
Readers may wish to contrast with the HTTP Re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_largest_left_truncatable_prime_in_a_given_base | Find largest left truncatable prime in a given base | A truncatable prime is one where all non-empty substrings that finish at the end of the number (right-substrings) are also primes when understood as numbers in a particular base. The largest such prime in a given (integer) base is therefore computable, provided the base is larger than 2.
Let's consider what happens in... | #Go | Go | package main
import (
"fmt"
"math/big"
)
var smallPrimes = [...]int{2, 3, 5, 7, 11, 13, 17, 19, 23, 29}
const maxStack = 128
var (
tens, values [maxStack]big.Int
bigTemp, answer = new(big.Int), new(big.Int)
base, seenDepth int
)
func addDigit(i int) {
for d := 1; d < base; d++ {
... | Give a code snippet in #Go
A truncatable prime is one where all non-empty substrings that finish at the end of the number (right-substrings) are also primes when understood as numbers in a particular base. The largest such prime in a given (integer) base is therefore computable, provided the base is larger than 2.
Le... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #BASIC256 | BASIC256 | f = freefile
filename$ = "file.txt"
open f, filename$
while not eof(f)
print readline(f)
end while
close f
end | Give a code snippet in #BASIC256
Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Temperature_conversion | Temperature conversion | There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 kelvin.
0 kelvin is absolute z... | #Haskell | Haskell | import System.Exit (die)
import Control.Monad (mapM_)
main = do
putStrLn "Please enter temperature in kelvin: "
input <- getLine
let kelvin = read input
if kelvin < 0.0
then die "Temp cannot be negative"
else mapM_ putStrLn $ convert kelvin
convert :: Double -> [String]
convert n = zipWith (++) ... | Give a code snippet in #Haskell
There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.1... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_unique_characters | Determine if a string has all unique characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length (as the strings are being ... | #Lua | Lua | local find, format = string.find, string.format
local function printf(fmt, ...) print(format(fmt,...)) end
local pattern = '(.).-%1' -- '(.)' .. '.-' .. '%1'
function report_dup_char(subject)
local pos1, pos2, char = find(subject, pattern)
local prefix = format('"%s" (%d)', subject, #subject)
if pos1 ... | Give a code snippet in #Lua
Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are unique
indicate if or which character is duplicated and where
display each string and its length... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Lah_numbers | Lah numbers | Lah numbers, sometimes referred to as Stirling numbers of the third kind, are coefficients of polynomial expansions expressing rising factorials in terms of falling factorials.
Unsigned Lah numbers count the number of ways a set of n elements can be partitioned into k non-empty linearly ordered subsets.
Lah numbers a... | #Arturo | Arturo | factorial: function [n]-> product 1..n
lah: function [n,k][
if k=1 -> return factorial n
if k=n -> return 1
if k>n -> return 0
if or? k<1 n<1 -> return 0
return (((factorial n)*factorial n-1) / ((factorial k) * factorial k-1)) / factorial n-k
]
print @["n/k"] ++ map to [:string] 1..12 's -> pad ... | Give a code snippet in #Arturo
Lah numbers, sometimes referred to as Stirling numbers of the third kind, are coefficients of polynomial expansions expressing rising factorials in terms of falling factorials.
Unsigned Lah numbers count the number of ways a set of n elements can be partitioned into k non-empty linearly... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Death_Star | Death Star |
Task
Display a region that consists of a large sphere with part of a smaller sphere removed from it as a result of geometric subtraction.
(This will basically produce a shape like a "death star".)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
| #C | C | #include <stdio.h>
#include <math.h>
#include <unistd.h>
const char *shades = ".:!*oe&#%@";
double light[3] = { -50, 0, 50 };
void normalize(double * v)
{
double len = sqrt(v[0]*v[0] + v[1]*v[1] + v[2]*v[2]);
v[0] /= len; v[1] /= len; v[2] /= len;
}
double dot(double *x, double *y)
{
double d = x[0]*y[0] + x[1... | Give a code snippet in #C
Task
Display a region that consists of a large sphere with part of a smaller sphere removed from it as a result of geometric subtraction.
(This will basically produce a shape like a "death star".)
Related tasks
draw a sphere
draw a cuboid
draw a rotating cube
write language name i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catamorphism | Catamorphism | Reduce is a function or method that is used to take the values in an array or a list and apply a function to successive members of the list to produce (or reduce them to), a single value.
Task
Show how reduce (or foldl or foldr etc), work (or would be implemented) in your language.
See also
Wikipedia article: ... | #Kotlin | Kotlin | fun main(args: Array<String>) {
val a = intArrayOf(1, 2, 3, 4, 5)
println("Array : ${a.joinToString(", ")}")
println("Sum : ${a.reduce { x, y -> x + y }}")
println("Difference : ${a.reduce { x, y -> x - y }}")
println("Product : ${a.reduce { x, y -> x * y }}")
println("Minimum... | Give a code snippet in #Kotlin
Reduce is a function or method that is used to take the values in an array or a list and apply a function to successive members of the list to produce (or reduce them to), a single value.
Task
Show how reduce (or foldl or foldr etc), work (or would be implemented) in your language.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Department_numbers | Department numbers | There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (different from each other) and mu... | #Transd | Transd | #lang transd
MainModule : {
_start: (lambda
(lout "Police | Sanit. | Fire")
(for i in Range(1 8) where (not (mod i 2)) do
(for j in Range(1 8) where (neq i j) do
(for k in Range(1 8) where (and (neq i k) (neq j k)) do
(if (eq (+ i j k) 12) (lout i " "... | Give a code snippet in #Transd
There is a highly organized city that has decided to assign a number to each of their departments:
police department
sanitation department
fire department
Each department can have a number between 1 and 7 (inclusive).
The three department numbers are to be unique (d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #MUMPS | MUMPS | SYSTIME
NEW PH
SET PH=$PIECE($HOROLOG,",",2)
WRITE "The system time is ",PH\3600,":",PH\60#60,":",PH#60
KILL PH
QUIT | Give a code snippet in #MUMPS
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
... | 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
| #Kotlin | Kotlin |
{if true then YES else NO}
-> YES
{if false then YES else NO}
-> NO
| Give a code snippet in #Kotlin
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/Rep-string | Rep-string | Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at least twice in the original.
For e... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
/* REXX ***************************************************************
* 11.05.2013 Walter Pachl
**********************************************************************/
runSample(arg)
return
/**
* Test for rep-strings
* @param s_str a s... | Give a code snippet in #NetRexx
Given a series of ones and zeroes in a string, define a repeated string or rep-string as a string which is created by repeating a substring of the first N characters of the string truncated on the right to the length of the input string, and in which the substring appears repeated at le... | 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
| #11l | 11l | os:(‘pause’) | Give a code snippet in #11l
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/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... | #Processing | Processing | void setup() {
for (int i = 1; i <= 5; i++) {
int count = 0;
print("k = " + i + ": ");
int n = 2;
while (count < 10) {
if (isAlmostPrime(i, n)) {
count++;
print(n + " ");
}
n++;
}
println();
}
}
boolean isAlmostPrime(int k, int n) {
if (countPrimeFactors... | Give a code snippet in #Processing
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,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_directory | Empty directory | Starting with a path to some directory, determine whether the directory is empty.
An empty directory contains no files nor subdirectories.
With Unix or Windows systems, every directory contains an entry for “.” and almost every directory contains “..” (except for a root directory); an empty directory contains no other... | #Nim | Nim | import os, rdstdin
var empty = true
for f in walkDir(readLineFromStdin "directory: "):
empty = false
break
echo empty | Give a code snippet in #Nim
Starting with a path to some directory, determine whether the directory is empty.
An empty directory contains no files nor subdirectories.
With Unix or Windows systems, every directory contains an entry for “.” and almost every directory contains “..” (except for a root directory); an empt... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Get_system_command_output | Get system command output | Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| #Phix | Phix | without js -- system_exec, file i/o
constant tmp = "hostname.txt",
cmd = iff(platform()=WINDOWS?"hostname":"uname -n")
{} = system_exec(sprintf("%s > %s",{cmd,tmp}),4)
string host = trim(get_text(tmp))
{} = delete_file(tmp)
?host
| Give a code snippet in #Phix
Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations | Combinations | Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0 2 4
0 3 4
1 2 3
1 2 4
1 3 4
2 3 4
... | #TXR | TXR | (defun comb-n-m (n m)
(comb (range* 0 n) m))
(put-line `3 comb 5 = @(comb-n-m 5 3)`) | Give a code snippet in #TXR
Task
Given non-negative integers m and n, generate all size m combinations of the integers from 0 (zero) to n-1 in sorted order (each combination is sorted and the entire table is sorted).
Example
3 comb 5 is:
0 1 2
0 1 3
0 1 4
0 2 3
0 2 4
0... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calendar | Calendar | Create a routine that will generate a text calendar for any year.
Test the calendar by generating a calendar for the year 1969, on a device of the time.
Choose one of the following devices:
A line printer with a width of 132 characters.
An IBM 3278 model 4 terminal (80×43 display with accented characters). Target fo... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "time.s7i";
const func string: center (in string: stri, in integer: length) is
return ("" lpad (length - length(stri)) div 2 <& stri) rpad length;
const proc: printCalendar (in integer: year, in integer: cols) is func
local
var time: date is time.value;
var integer: d... | Give a code snippet in #Seed7
Create a routine that will generate a text calendar for any year.
Test the calendar by generating a calendar for the year 1969, on a device of the time.
Choose one of the following devices:
A line printer with a width of 132 characters.
An IBM 3278 model 4 terminal (80×43 display with ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_if_a_point_is_within_a_triangle | Find if a point is within a triangle | Find if a point is within a triangle.
Task
Assume points are on a plane defined by (x, y) real number coordinates.
Given a point P(x, y) and a triangle formed by points A, B, and C, determine if P is within triangle ABC.
You may use any algorithm.
Bonus: explain why the algorithm you chose works.
Re... | #Kotlin | Kotlin | import kotlin.math.max
import kotlin.math.min
private const val EPS = 0.001
private const val EPS_SQUARE = EPS * EPS
private fun test(t: Triangle, p: Point) {
println(t)
println("Point $p is within triangle ? ${t.within(p)}")
}
fun main() {
var p1 = Point(1.5, 2.4)
var p2 = Point(5.1, -3.1)
va... | Give a code snippet in #Kotlin
Find if a point is within a triangle.
Task
Assume points are on a plane defined by (x, y) real number coordinates.
Given a point P(x, y) and a triangle formed by points A, B, and C, determine if P is within triangle ABC.
You may use any algorithm.
Bonus: explain why the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Formatted_numeric_output | Formatted numeric output | Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| #PowerShell | PowerShell | '{0:00000.000}' -f 7.125 | Give a code snippet in #PowerShell
Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #FreeBASIC | FreeBASIC | ' VERSION 16-03-2016
' COMPILE WITH: FBC -S CONSOLE
' TRUE/FALSE ARE BUILT-IN CONSTANTS SINCE FREEBASIC 1.04
' BUT WE HAVE TO DEFINE THEM FOR OLDER VERSIONS.
#IFNDEF TRUE
#DEFINE FALSE 0
#DEFINE TRUE NOT FALSE
#ENDIF
FUNCTION WD(M AS INTEGER, D AS INTEGER, Y AS INTEGER) AS INTEGER
' ZELLERISH
' 0 = ... | Give a code snippet in #FreeBASIC
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 th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Quicksort | Sorting algorithms/Quicksort |
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
... | #Raku | Raku | # Empty list sorts to the empty list
multi quicksort([]) { () }
# Otherwise, extract first item as pivot...
multi quicksort([$pivot, *@rest]) {
# Partition.
my $before := @rest.grep(* before $pivot);
my $after := @rest.grep(* !before $pivot);
# Sort the partitions.
flat quicksort($befor... | Give a code snippet in #Raku
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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 |... | #Lasso | Lasso | local(
number1 = integer(web_request -> param('number1')),
number2 = integer(web_request -> param('number2'))
)
#number1 < #number2 ? 'Number 1 is less than Number 2' | 'Number 1 is not less than Number 2'
'<br />'
#number1 == #number2 ? 'Number 1 is the same as Number 2' | 'Number 1 is not the same as Number 2'
'<... | Give a code snippet in #Lasso
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/P-value_correction | P-value correction | Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-values are sometimes called "q... | #Wren | Wren | import "/dynamic" for Enum
import "/fmt" for Fmt
import "/seq" for Lst
import "/math" for Nums
import "/sort" for Sort
var Direction = Enum.create("Direction", ["UP", "DOWN"])
// test also for 'Unknown' correction type
var types = [
"Benjamini-Hochberg", "Benjamini-Yekutieli", "Bonferroni", "Hochberg",
"Hol... | Give a code snippet in #Wren
Given a list of p-values, adjust the p-values for multiple comparisons. This is done in order to control the false positive, or Type 1 error rate.
This is also known as the "false discovery rate" (FDR). After adjustment, the p-values will be higher but still inside [0,1].
The adjusted p-... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Julia | Julia | dict = Dict('a' => 97, 'b' => 98) # list keys/values
# Dict{Char,Int64} with 2 entries:
# 'b' => 98
# 'a' => 97
dict = Dict(c => Int(c) for c = 'a':'d') # dict comprehension
# Dict{Char,Int64} with 4 entries:
# 'b' => 98
# 'a' => 97
# 'd' => 100
# 'c' => 99
dict['é'] = 233; dict # add an element
# Dict{... | Give a code snippet in #Julia
Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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
| #PARI.2FGP | PARI/GP | #!/usr/bin/perl
do "include.pl"; # Utilize source from another file
sayhello(); | Give a code snippet in #PARI.2FGP
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/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #Julia | Julia | i = zero(BigInt) # or i = big(0)
while true
println(i += 1)
end | Give a code snippet in #Julia
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations li... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RSA_code | RSA code | Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encryption is that you can distribute the... | #Go | Go | package main
import (
"fmt"
"math/big"
)
func main() {
var n, e, d, bb, ptn, etn, dtn big.Int
pt := "Rosetta Code"
fmt.Println("Plain text: ", pt)
// a key set big enough to hold 16 bytes of plain text in
// a single block (to simplify the example) and also big enough
//... | Give a code snippet in #Go
Given an RSA key (n,e,d), construct a program to encrypt and decrypt plaintext messages strings.
Background
RSA code is used to encode secret messages. It is named after Ron Rivest, Adi Shamir, and Leonard Adleman who published it at MIT in 1977. The advantage of this type of encryption is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anagrams | Anagrams | When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that contain the most words in them.
Related tasks
Word plays
... | #Euphoria | Euphoria | include sort.e
function compare_keys(sequence a, sequence b)
return compare(a[1],b[1])
end function
constant fn = open("unixdict.txt","r")
sequence words, anagrams
object word
words = {}
while 1 do
word = gets(fn)
if atom(word) then
exit
end if
word = word[1..$-1] -- truncate new-line ch... | Give a code snippet in #Euphoria
When two or more words are composed of the same characters, but in a different order, they are called anagrams.
Task[edit]
Using the word list at http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
find the sets of words that share the same characters that contain the most words i... | 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... | #Tcl | Tcl | string repeat "ha" 5 ;# => hahahahaha | Give a code snippet in #Tcl
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/Sum_multiples_of_3_and_5 | Sum multiples of 3 and 5 | Task
The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n.
Show output for n = 1000.
This is is the same as Project Euler problem 1.
Extra credit: do this efficiently for n = 1e20 or higher.
| #BCPL | BCPL |
GET "libhdr"
LET sumdiv(n, d) = VALOF {
LET m = n/d
RESULTIS m*(m + 1)/2 * d
}
LET sum3or5(n) = sumdiv(n, 3) + sumdiv(n, 5) - sumdiv(n, 15)
LET start() = VALOF {
LET sum = 0
LET n = 1
FOR k = 1 TO 999 DO
IF k MOD 3 = 0 | k MOD 5 = 0 THEN sum +:= k
writef("The sum of the multipl... | Give a code snippet in #BCPL
Task
The objective is to write a function that finds the sum of all positive multiples of 3 or 5 below n.
Show output for n = 1000.
This is is the same as Project Euler problem 1.
Extra credit: do this efficiently for n = 1e20 or higher.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #Common_Lisp | Common Lisp | (defun friday-before (year month day)
(let*
((timestamp (encode-universal-time 0 0 12 day month year))
(weekday (nth 6 (multiple-value-list (decode-universal-time timestamp))))
(fri (- timestamp (* (+ (mod (+ weekday 2) 7) 1) 86400))))
(multiple-value-bind (_ _ _ d m y) (decode-universal-time fri)
(l... | Give a code snippet in #Common_Lisp
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an ov... | #PicoLisp | PicoLisp | (de ** (X N) # N th power of X
(if (ge0 N)
(let Y 1
(loop
(when (bit? 1 N)
(setq Y (* Y X)) )
(T (=0 (setq N (>> 1 N)))
Y )
(setq X (* X X)) ) )
0 ) ) | Give a code snippet in #PicoLisp
Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evolutionary_algorithm | Evolutionary algorithm | Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its argument to the target string.... | #Vlang | Vlang | import rand
import rand.seed
const target = "METHINKS IT IS LIKE A WEASEL".bytes()
const set = "ABCDEFGHIJKLMNOPQRSTUVWXYZ ".bytes()
fn initialize() []u8 {
rand.seed(seed.time_seed_array(2))
mut parent := []u8{len: target.len}
for i in 0..parent.len {
parent[i] = set[rand.intn(set.len) or {0}]... | Give a code snippet in #Vlang
Starting with:
The target string: "METHINKS IT IS LIKE A WEASEL".
An array of random characters chosen from the set of upper-case letters together with the space, and of the same length as the target string. (Call it the parent).
A fitness function that computes the ‘closeness’ of its... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Count_examples | Rosetta Code/Count examples | task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'll need to use the Media Wiki AP... | #Lasso | Lasso | local(root = json_deserialize(curl('http://rosettacode.org/mw/api.php?action=query&list=categorymembers&cmtitle=Category:Programming_Tasks&cmlimit=10&format=json')->result))
local(tasks = array, title = string, urltitle = string, thiscount = 0, totalex = 0)
with i in #root->find('query')->find('categorymembers') do => ... | Give a code snippet in #Lasso
task
Essentially, count the number of occurrences of =={{header| on each task page.
Output:
100 doors: 20 examples.
99 Bottles of Beer: 29 examples.
Abstract type: 10 examples.
Total: X examples.
For a full output, updated periodically, see Rosetta Code/Count examples/Full list.
You'l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cut_a_rectangle | Cut a rectangle | A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such paths for 2 × 2 and 4 × 3 rectangles... | #Groovy | Groovy | class CutRectangle {
private static int[][] dirs = [[0, -1], [-1, 0], [0, 1], [1, 0]]
static void main(String[] args) {
cutRectangle(2, 2)
cutRectangle(4, 3)
}
static void cutRectangle(int w, int h) {
if (w % 2 == 1 && h % 2 == 1) {
return
}
int[... | Give a code snippet in #Groovy
A given rectangle is made from m × n squares. If m and n are not both odd, then it is possible to cut a path through the rectangle along the square edges such that the rectangle splits into two connected pieces with the same shape (after rotating one of the pieces by 180°). All such path... | 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... | #Action.21 | Action! | PROC KnuthShuffle(BYTE ARRAY tab BYTE size)
BYTE i,j,tmp
i=size-1
WHILE i>0
DO
j=Rand(i+1)
tmp=tab(i)
tab(i)=tab(j)
tab(j)=tmp
i==-1
OD
RETURN
BYTE FUNC IsSorted(BYTE ARRAY tab BYTE size)
BYTE i
FOR i=0 TO size-2
DO
IF tab(i)>tab(i+1) THEN
RETURN (0)
FI
OD
RETUR... | Give a code snippet in #Action.21
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.
Th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #QB64_2 | QB64 | _DEFINE F AS _UNSIGNED _INTEGER64
CLS
PRINT
PRINT "Enter 40 to more easily see the difference in calculation speeds."
PRINT
INPUT "Enter n for Fibonacci(n): ", n
PRINT
PRINT " Analytic Method (Fastest): F("; LTRIM$(STR$(n)); ") ="; fA(n)
PRINT "Iterative Method (Fast): F("; LTRIM$(STR$(n)); ") ="; fI(n)
PRINT "Recur... | Give a code snippet in #QB64_2
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions ar... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #Intercal | Intercal | bottles := method(i,
if(i==0, return "no more bottles of beer")
if(i==1, return "1 bottle of beer")
"" .. i .. " bottles of beer"
)
for(i, 99, 1, -1,
write(
bottles(i), " on the wall, ",
bottles(i), ",\n",
"take one down, pass it around,\n",
bottles(i - 1), " on the wall... | Give a code snippet in #Intercal
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Maximum_triangle_path_sum | Maximum triangle path sum | Starting from the top of a pyramid of numbers like this, you can walk down going one step on the right or on the left, until you reach the bottom row:
55
94 48
95 30 96
77 71 26 67
One of such walks is 55 - 94 - 30 - 26.
You... | #PL.2FI | PL/I | *process source xref attributes or(!);
triang: Proc Options(Main);
Dcl nn(18,18) Bin Fixed(31);
Dcl (rows,i,j) Bin Fixed(31);
Dcl (p,k,kn) Bin Fixed(31);
Call f_r(1 ,' 55 ');
Call f_r(2 ,' 94 48 ');
Call f_r(3 ,' ... | Give a code snippet in #PL.2FI
Starting from the top of a pyramid of numbers like this, you can walk down going one step on the right or on the left, until you reach the bottom row:
55
94 48
95 30 96
77 71 26 67
One of such... | 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... | #Go | Go | package main
import (
"bytes"
"encoding/csv"
"fmt"
"html/template"
"strings"
)
var c = `Character,Speech
The multitude,The messiah! Show us the messiah!
Brians mother,<angry>Now you listen here! He's not the messiah; he's a very naughty boy! Now go away!</angry>
The multitude,Who are you?
Brians... | Give a code snippet in #Go
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
Creat... | 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 ... | #Picat | Picat | interactive =>
print("> "),
MaxNum = read_int(),
Map = new_map(),
print("> "),
while (Line = read_line(), Line != "")
[N,V] = split(Line),
Map.put(N.to_int,V),
print("> ")
end,
general_fizzbuzz(MaxNum,Map.to_list.sort),
nl.
general_fizzbuzz(N,L) =>
FB = [I.to_string : I in 1..... | Give a code snippet in #Picat
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 wit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/List_rooted_trees | List rooted trees | You came back from grocery shopping. After putting away all the goods, you are left with a pile of plastic bags, which you want to save for later use, so you take one bag and stuff all the others into it, and throw it under the sink. In doing so, you realize that there are various ways of nesting the bags, with all... | #11l | 11l | F bagchain(x, n, bb, start = 0)
I n == 0
R [x]
[(Int, String)] out
L(i) start .< bb.len
V (c, s) = bb[i]
I c <= n
out.extend(bagchain((x[0] + c, x[1]‘’s), n - c, bb, i))
R out
F bags(n)
I n == 0
R [(0, ‘’)]
[(Int, String)] upto
L(x) (n - 1 .< 0).step(-1)
... | Give a code snippet in #11l
You came back from grocery shopping. After putting away all the goods, you are left with a pile of plastic bags, which you want to save for later use, so you take one bag and stuff all the others into it, and throw it under the sink. In doing so, you realize that there are various ways ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_whitespace_from_a_string/Top_and_tail | Strip whitespace from a string/Top and tail | Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace removed
For the purposes of thi... | #Perl | Perl | sub ltrim { shift =~ s/^\s+//r }
sub rtrim { shift =~ s/\s+$//r }
sub trim { ltrim rtrim shift }
# Usage:
my $p = " this is a string ";
print "'", $p, "'\n";
print "'", trim($p), "'\n";
print "'", ltrim($p), "'\n";
print "'", rtrim($p), "'\n"; | Give a code snippet in #Perl
Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace rem... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division | Sequence of primes by trial division | Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by... | #PowerShell | PowerShell |
function eratosthenes ($n) {
if($n -ge 1){
$prime = @(1..($n+1) | foreach{$true})
$prime[1] = $false
$m = [Math]::Floor([Math]::Sqrt($n))
for($i = 2; $i -le $m; $i++) {
if($prime[$i]) {
for($j = $i*$i; $j -le $n; $j += $i) {
$prime[$j... | Give a code snippet in #PowerShell
Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for bei... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix-exponentiation_operator | Matrix-exponentiation operator | Most programming languages have a built-in implementation of exponentiation for integers and reals only.
Task
Demonstrate how to implement matrix exponentiation as an operator.
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | a = {{3, 2}, {4, 1}};
MatrixPower[a, 0]
MatrixPower[a, 1]
MatrixPower[a, -1]
MatrixPower[a, 4]
MatrixPower[a, 1/2]
MatrixPower[a, Pi] | Give a code snippet in #Mathematica.2FWolfram_Language
Most programming languages have a built-in implementation of exponentiation for integers and reals only.
Task
Demonstrate how to implement matrix exponentiation as an operator.
| 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... | #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
#Macro If2(condition1, condition2)
#Define Else1 ElseIf CBool(condition1) Then
#Define Else2 ElseIf CBool(condition2) Then
If CBool(condition1) AndAlso CBool(condition2) Then
#Endmacro
Sub test(a As Integer, b As Integer)
If2(a > 0, b > 0)
print "both positive"
Else1
print "first posit... | Give a code snippet in #FreeBASIC
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 (... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singleton | Singleton | A Global Singleton is a class of which only one instance exists within a program.
Any attempt to use non-static members of the class involves performing operations on this one instance.
| #C.23 | C# | public sealed class Singleton1 //Lazy: Yes ||| Thread-safe: Yes ||| Uses locking: Yes
{
private static Singleton1 instance;
private static readonly object lockObj = new object();
public static Singleton1 Instance {
get {
lock(lockObj) {
if (instance == null) {
... | Give a code snippet in #C.23
A Global Singleton is a class of which only one instance exists within a program.
Any attempt to use non-static members of the class involves performing operations on this one instance.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Search_a_list_of_records | Search a list of records | Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task[edit]
Write a function/method/et... | #C | C |
#include <stdint.h> /* intptr_t */
#include <stdio.h>
#include <stdlib.h> /* bsearch */
#include <string.h>
#include <search.h> /* lfind */
#define LEN(x) (sizeof(x) / sizeof(x[0]))
struct cd {
char *name;
double population;
};
/* Return -1 if name could not be found */
int search_get_index_by_name(cons... | Give a code snippet in #C
Many programming languages provide convenient ways to look for a known value in a simple list of strings or numbers.
But what if the elements of the list are themselves compound records/objects/data-structures, and the search condition is more complex than a simple equality test?
Task[edit]... | christopher/rosetta-code |
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