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/Pernicious_numbers | Pernicious numbers | A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is prime, and therefore
22 is a pe... | #AppleScript | AppleScript | on isPrime(n)
if (n < 4) then return (n > 1)
if ((n mod 2 is 0) or (n mod 3 is 0)) then return false
repeat with i from 5 to (n ^ 0.5) div 1 by 6
if ((n mod i is 0) or (n mod (i + 2) is 0)) then return false
end repeat
return true
end isPrime
on isPernicious(n)
-- 8 bits at a time is... | Give a code snippet in #AppleScript
A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar ... | #Fortran | Fortran | program vigenere_cipher
implicit none
character(80) :: plaintext = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!", &
ciphertext = ""
character(14) :: key = "VIGENERECIPHER"
call encrypt(plaintext, ciphertext, key)
write(*,*) plaintext
write(*,*) ciphertex... | Give a code snippet in #Fortran
Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cantor_set | Cantor set | Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| #Raku | Raku | sub cantor ( Int $height ) {
my $width = 3 ** ($height - 1);
my @lines = ( "\c[FULL BLOCK]" x $width ) xx $height;
my sub _trim_middle_third ( $len, $start, $index ) {
my $seg = $len div 3
or return;
for ( $index ..^ $height ) X ( 0 ..^ $seg ) -> ( $i, $j ) {
@l... | Give a code snippet in #Raku
Task
Draw a Cantor set.
See details at this Wikipedia webpage: Cantor set
| christopher/rosetta-code | |
http://rosettacode.org/wiki/RPG_attributes_generator | RPG attributes generator | RPG = Role Playing Game.
You're running a tabletop RPG, and your players are creating characters.
Each character has six core attributes: strength, dexterity, constitution, intelligence, wisdom, and charisma.
One way of generating values for these attributes is to roll four, 6-sided dice (d6) and sum the three... | #Python | Python | import random
random.seed()
attributes_total = 0
count = 0
while attributes_total < 75 or count < 2:
attributes = []
for attribute in range(0, 6):
rolls = []
for roll in range(0, 4):
result = random.randint(1, 6)
rolls.append(result)
sorted_rolls = sorted(... | Give a code snippet in #Python
RPG = Role Playing Game.
You're running a tabletop RPG, and your players are creating characters.
Each character has six core attributes: strength, dexterity, constitution, intelligence, wisdom, and charisma.
One way of generating values for these attributes is to roll four, 6-s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #PicoLisp | PicoLisp | (push 'Stack 3)
(push 'Stack 2)
(push 'Stack 1) | Give a code snippet in #PicoLisp
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multifactorial | Multifactorial | The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(... | #Action.21 | Action! | INCLUDE "D2:REAL.ACT" ;from the Action! Tool Kit
PROC Multifactorial(INT n,d REAL POINTER res)
REAL r
IntToReal(1,res)
WHILE n>1
DO
IntToReal(n,r)
RealMult(res,r,res)
n==-d
OD
RETURN
PROC Main()
BYTE n,d
REAL r
Put(125) PutE() ;clear the screen
FOR d=1 TO 5
DO
PrintF("Degree ... | Give a code snippet in #Action.21
The factorial of a number, written as
n
!
{\displaystyle n!}
, is defined as
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{\displaystyle n!=n(n-1)(n-2)...(2)(1)}
.
Multifactorials generalize factorials as follows:
n
!
=
n
(
n
−
1
)
(
n
−
2
)
.
.
.
(
2
)
(
1
)
{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Literals/Integer | Literals/Integer | Some programming languages have ways of expressing integer literals in bases other than the normal base ten.
Task
Show how integer literals can be expressed in as many bases as your language allows.
Note: this should not involve the calling of any functions/methods, but should be interpreted by the compiler or... | #GAP | GAP | # Only decimal integers, but of any length
31415926
1606938044258990275541962092341162602522202993782792835301376 | Give a code snippet in #GAP
Some programming languages have ways of expressing integer literals in bases other than the normal base ten.
Task
Show how integer literals can be expressed in as many bases as your language allows.
Note: this should not involve the calling of any functions/methods, but should be i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #Scala | Scala |
import scala.util.control.Exception.allCatch
def isNumber(s: String): Boolean = (allCatch opt s.toDouble).isDefined
| Give a code snippet in #Scala
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
A... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #SNOBOL4 | SNOBOL4 | while a = trim(input) :f(stop)
max = gt(a,max) a :(while)
stop output = max
end | Give a code snippet in #SNOBOL4
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Huffman_coding | Huffman coding | Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could just encode each letter wi... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define BYTES 256
struct huffcode {
int nbits;
int code;
};
typedef struct huffcode huffcode_t;
struct huffheap {
int *h;
int n, s, cs;
long *f;
};
typedef struct huffheap heap_t;
/* heap handling funcs */
static heap_t *_heap_create(int s, lo... | Give a code snippet in #C
Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could... | 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
| #Common_Lisp | Common Lisp | (trivial-shell:shell-command "uname -imp") | Give a code snippet in #Common_Lisp
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/Natural_sorting | Natural sorting |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Python | Python | # -*- coding: utf-8 -*-
# Not Python 3.x (Can't compare str and int)
from itertools import groupby
from unicodedata import decomposition, name
from pprint import pprint as pp
commonleaders = ['the'] # lowercase leading words to ignore
replacements = {u'ß': 'ss', # Map single char to replacement string
... | Give a code snippet in #Python
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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 ... | #JavaScript | JavaScript | #!/usr/bin/env node
var fs = require('fs');
var sys = require('sys');
var dictFile = process.argv[2] || "unixdict.txt";
var dict = {};
fs.readFileSync(dictFile)
.toString()
.split('\n')
.forEach(function(word) {
dict[word] = word.split("").reverse().join("");
});
function isSemordnilap(word) { return... | Give a code snippet in #JavaScript
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Solve_the_no_connection_puzzle | Solve the no connection puzzle | You are given a box with eight holes labelled A-to-H, connected by fifteen straight lines in the pattern as shown below:
A B
/│\ /│\
/ │ X │ \
/ │/ \│ \
C───D───E───F
\ │\ /│ /
\ │ X │ /
\│/ \│/
G H
You ar... | #Julia | Julia |
using Combinatorics
const HOLES = ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H']
const PEGS = [1, 2, 3, 4, 5, 6, 7, 8]
const EDGES = [('A', 'C'), ('A', 'D'), ('A', 'E'),
('B', 'D'), ('B', 'E'), ('B', 'F'),
('C', 'G'), ('C', 'D'), ('D', 'G'),
('D', 'E'), ('D', 'H'), ('E', 'F'),... | Give a code snippet in #Julia
You are given a box with eight holes labelled A-to-H, connected by fifteen straight lines in the pattern as shown below:
A B
/│\ /│\
/ │ X │ \
/ │/ \│ \
C───D───E───F
\ │\ /│ /
\ │ X │ /
\│/... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_a_function_in_a_shared_library | Call a function in a shared library | Show how to call a function in a shared library (without dynamically linking to it at compile-time). In particular, show how to call the shared library function if the library is available, otherwise use an internal equivalent function.
This is a special case of calling a foreign language function where the focus is c... | #Ursala | Ursala | #import std
#import flo
my_replacement = fleq/0.?/~& negative
abs = math.|fabs my_replacement | Give a code snippet in #Ursala
Show how to call a function in a shared library (without dynamically linking to it at compile-time). In particular, show how to call the shared library function if the library is available, otherwise use an internal equivalent function.
This is a special case of calling a foreign langua... | 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.
| #Raku | Raku | for open('test.txt').lines
{
.say
} | Give a code snippet in #Raku
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/Perfect_numbers | Perfect numbers | Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself).
Note: The faster Luca... | #Raku | Raku | sub is-perf($n) { $n == [+] grep $n %% *, 1 .. $n div 2 }
# used as
put ((1..Inf).hyper.grep: {.&is-perf})[^4]; | Give a code snippet in #Raku
Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Last_Friday_of_each_month | Last Friday of each month | Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
2012-02-24
2012-03-30
2012-04-27
2012-05-25
20... | #MATLAB_.2F_Octave | MATLAB / Octave | function t = last_fridays_of_year(y)
t1 = datenum([y,1,1,0,0,0]);
t2 = datenum([y,12,31,0,0,0]);
t = datevec(t1:t2);
t = t(strmatch('Friday', datestr(t,'dddd')), :); % find all Fridays
t = t([find(diff(t(:,2)) > 0); end], :); % find Fridays before change of month
end;
datestr(last_fridays_o... | Give a code snippet in #MATLAB_.2F_Octave
Task
Write a program or a script that returns the date of the last Fridays of each month of a given year.
The year may be given through any simple input method in your language (command line, std in, etc).
Example of an expected output:
./last_fridays 2012
2012-01-27
201... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Longest_common_substring | Longest common substring | Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are consecutive characters within a string.... | #BaCon | BaCon | FUNCTION Common_Sub$(haystack$, needle$)
WHILE LEN(needle$)
FOR x = LEN(needle$) DOWNTO 1
IF INSTR(haystack$, LEFT$(needle$, x)) THEN RETURN LEFT$(needle$, x)
NEXT
needle$ = MID$(needle$, 2)
WEND
EXIT
ENDFUNC
PRINT Common_Sub$("thisisatest", "testing123testing") | Give a code snippet in #BaCon
Task
Write a function that returns the longest common substring of two strings.
Use it within a program that demonstrates sample output from the function, which will consist of the longest common substring between "thisisatest" and "testing123testing".
Note that substrings are consecut... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Numerical_integration/Gauss-Legendre_Quadrature | Numerical integration/Gauss-Legendre Quadrature |
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting function
W
(
x
)
{\displaystyle ... | #Phix | Phix | with javascript_semantics
integer order = 0
sequence legendreRoots = {},
legendreWeights = {}
function legendre(integer term, atom z)
if term=0 then
return 1
elsif term=1 then
return z
else
return ((2*term-1)*z*legendre(term-1,z)-(term-1)*legendre(term-2,z))/term
en... | Give a code snippet in #Phix
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting function... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_that_file_exists | Check that file exists | Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works with:
zero-length files
an ... | #SenseTalk | SenseTalk |
put file "input.txt" exists
put folder "docs" exists
put file "/input.txt" exists
put there is a folder "/docs"
| Give a code snippet in #SenseTalk
Task
Verify that a file called input.txt and a directory called docs exist.
This should be done twice:
once for the current working directory, and
once for a file and a directory in the filesystem root.
Optional criteria (May 2015): verify it works... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Angle_difference_between_two_bearings | Angle difference between two bearings | Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range -180 to +180 degrees.
... | #OCaml | OCaml | let get_diff b1 b2 =
let r = mod_float (b2 -. b1) 360.0 in
if r < -180.0
then r +. 360.0
else if r >= 180.0
then r -. 360.0
else r
let () =
print_endline "Input in -180 to +180 range";
Printf.printf " %g\n" (get_diff 20.0 45.0);
Printf.printf " %g\n" (get_diff (-45.0) 45.0);
Printf.printf " %g\n" ... | Give a code snippet in #OCaml
Finding the angle between two bearings is often confusing.[1]
Task
Find the angle which is the result of the subtraction b2 - b1, where b1 and b2 are the bearings.
Input bearings are expressed in the range -180 to +180 degrees.
The result is also expressed in the range ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Huffman_coding | Huffman coding | Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could just encode each letter wi... | #JavaScript | JavaScript | function HuffmanEncoding(str) {
this.str = str;
var count_chars = {};
for (var i = 0; i < str.length; i++)
if (str[i] in count_chars)
count_chars[str[i]] ++;
else
count_chars[str[i]] = 1;
var pq = new BinaryHeap(function(x){return x[0];});
for (var ch i... | Give a code snippet in #JavaScript
Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols.
For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #ERRE | ERRE |
PROGRAM ACKERMAN
!
! computes Ackermann function
! (second version for rosettacode.org)
!
!$INTEGER
DIM STACK[10000]
!$INCLUDE="PC.LIB"
PROCEDURE ACK(M,N->N)
LOOP
CURSOR_SAVE(->CURX%,CURY%)
LOCATE(8,1)
PRINT("Livello Stack:";S;" ")
LOCATE(CURY%,CURX%)
IF M<>0 THEN
IF N<>0 THEN... | Give a code snippet in #ERRE
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Leonardo_numbers | Leonardo numbers |
Leonardo numbers are also known as the Leonardo series.
The Leonardo numbers are a sequence of numbers defined by:
L(0) = 1 [1st equation]
L(1) = 1 [2nd equation]
L(n) = L(n-1) + L(n-2) + 1 ... | #PicoLisp | PicoLisp | (de leo (A B C)
(default A 1 B 1 C 1)
(make
(do 25
(inc
'B
(+ (link (swap 'A B)) C) ) ) ) )
(println 'Leonardo (leo))
(println 'Fibonacci (leo 0 1 0)) | Give a code snippet in #PicoLisp
Leonardo numbers are also known as the Leonardo series.
The Leonardo numbers are a sequence of numbers defined by:
L(0) = 1 [1st equation]
L(1) = 1 [2nd equation]
L(n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #Maxima | Maxima | f(a, b):= a*b; | Give a code snippet in #Maxima
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Higher-order_functions | Higher-order functions | Task
Pass a function as an argument to another function.
Related task
First-class functions
| #6502_Assembly | 6502 Assembly | macro PrintOutput,input,addr
; input: desired function's input
; addr: function you wish to call
LDA #<\addr ;#< represents this number's low byte
STA z_L
LDA #>\addr ;#> represents this number's high byte
STA z_H
LDA \input
JSR doPrintOutput
endm | Give a code snippet in #6502_Assembly
Task
Pass a function as an argument to another function.
Related task
First-class functions
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/Continuous | Knapsack problem/Continuous |
A thief burgles a butcher's shop, where he can select from some items.
The thief knows the weights and prices of each items. Because he has a knapsack with 15 kg maximal capacity, he wants to select the items such that he would have his profit maximized. He may cut the items; the item has a reduced price after... | #PureBasic | PureBasic | Structure item
name.s
weight.f ;units are kilograms (kg)
Value.f
vDensity.f ;the density of the value, i.e. value/weight, and yes I made up the term ;)
EndStructure
#maxWeight = 15
Global itemCount = 0 ;this will be increased as needed to match actual count
Global Dim items.item(itemCount)
Procedure addIt... | Give a code snippet in #PureBasic
A thief burgles a butcher's shop, where he can select from some items.
The thief knows the weights and prices of each items. Because he has a knapsack with 15 kg maximal capacity, he wants to select the items such that he would have his profit maximized. He may cut the items; ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rate_counter | Rate counter | Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus.
Multiple approaches are allowed (even preferable), so long as they can accomplish these goals:
Run N seconds worth... | #Delphi | Delphi |
program Rate_counter;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
System.Diagnostics;
var
a: Integer;
function TickToString(Tick: Int64): string;
var
ns, us, ms, s, t: Cardinal;
begin
Result := '';
ns := (Tick mod 10) * 100;
if ns > 0 then
Result := format(' %dns', [ns]);
t := Tick div 10;
... | Give a code snippet in #Delphi
Of interest is the code that performs the actual measurements. Any other code (such as job implementation or dispatching) that is required to demonstrate the rate tracking is helpful, but not the focus.
Multiple approaches are allowed (even preferable), so long as they can accomplish th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Display_an_extended_character | Terminal control/Display an extended character | Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| #Forth | Forth | 163 xemit \ , or
s" £" type | Give a code snippet in #Forth
Task
Display an extended (non ASCII) character onto the terminal.
Specifically, display a £ (GBP currency sign).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Damm_algorithm | Damm algorithm | The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors.
The algorithm is named after H. Michael Damm.
Task
Verify the checksum, stored as last digit of an input.
| #Groovy | Groovy | class DammAlgorithm {
private static final int[][] TABLE = [
[0, 3, 1, 7, 5, 9, 8, 6, 4, 2],
[7, 0, 9, 2, 1, 5, 4, 8, 6, 3],
[4, 2, 0, 6, 8, 7, 1, 3, 5, 9],
[1, 7, 5, 0, 9, 8, 3, 4, 2, 6],
[6, 1, 2, 3, 0, 4, 5, 9, 7, 8],
[3, 6, 7, 4, 2, 0, 9, 5, 8, 1],
[5, 8, ... | Give a code snippet in #Groovy
The Damm algorithm is a checksum algorithm which detects all single digit errors and adjacent transposition errors.
The algorithm is named after H. Michael Damm.
Task
Verify the checksum, stored as last digit of an input.
| 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... | #Sidef | Sidef | Dir.new('/my/dir').is_empty; # true, false or nil | Give a code snippet in #Sidef
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 em... | 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 ... | #Rockstar | Rockstar |
Fibonacci takes Number
FNow is 0
FNext is 1
While FNow is less than Number
Say FNow
Put FNow into Temp
Put FNow into FNext
Put FNext plus Temp into FNext
Say Fibonacci taking 1000 (prints out highest number in Fibonacci sequence less than 1000)
| Give a code snippet in #Rockstar
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Regular_expressions | Regular expressions |
Task
match a string against a regular expression
substitute part of a string using a regular expression
| #JavaScript | JavaScript | var subject = "Hello world!";
// Two different ways to create the RegExp object
// Both examples use the exact same pattern... matching "hello "
var re_PatternToMatch = /Hello (World)/i; // creates a RegExp literal with case-insensitivity
var re_PatternToMatch2 = new RegExp("Hello (World)", "i");
// Test for a matc... | Give a code snippet in #JavaScript
Task
match a string against a regular expression
substitute part of a string using a regular expression
| christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #Logo | Logo | make "input readlist ; in: string 75000
show map "number? :input ; [false true]
make "input readword ; in: 75000
show :input + 123 ; 75123
make "input readword ; in: string 75000
show :input ; string 75000 | Give a code snippet in #Logo
User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #Erlang | Erlang | is_numeric(L) ->
Float = (catch erlang:list_to_float(L)),
Int = (catch erlang:list_to_integer(L)),
is_number(Float) orelse is_number(Int). | Give a code snippet in #Erlang
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/N%27th | N'th | Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show here the output for at least t... | #XLISP | XLISP | (DEFUN NTH (N)
(COND
((AND (> (MOD N 100) 3) (< (MOD N 100) 21)) `(,N TH))
((= (MOD N 10) 1) `(,N ST))
((= (MOD N 10) 2) `(,N ND))
((= (MOD N 10) 3) `(,N RD))
(T `(,N TH))))
(DEFUN RANGE (X Y)
(IF (<= X Y)
(CONS X (RANGE (+ X 1) Y))))
(DEFUN TEST-NTH ()
(D... | Give a code snippet in #XLISP
Write a function/method/subroutine/... that when given an integer greater than or equal to zero returns a string of the number followed by an apostrophe then the ordinal suffix.
Example
Returns would include 1'st 2'nd 3'rd 11'th 111'th 1001'st 1012'th
Task
Use your routine to show... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/RPN_calculator_algorithm | Parsing/RPN calculator algorithm | Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the RPN expression generated from the... | #Rust | Rust | fn rpn(text: &str) -> f64 {
let tokens = text.split_whitespace();
let mut stack: Vec<f64> = vec![];
println!("input operation stack");
for token in tokens {
print!("{:^5} ", token);
match token.parse() {
Ok(num) => {
stack.push(num);
println!... | Give a code snippet in #Rust
Task
Create a stack-based evaluator for an expression in reverse Polish notation (RPN) that also shows the changes in the stack as each individual token is processed as a table.
Assume an input of a correct, space separated, string of tokens of an RPN expression
Test with the RPN... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Collections | Collections | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Create a collection, and add a fe... | #Fancy | Fancy |
# creating an empty array and adding values
a = [] # => []
a[0]: 1 # => [1]
a[3]: 2 # => [1, nil, nil, 2]
# creating an array with the constructor
a = Array new # => []
| Give a code snippet in #Fancy
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Collections are abstractions to represent sets of values.
In statically-typed languages, the values are typically of a common data type.
Task
Cr... | 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... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
s1 = '' -- assignment
s2 = "" -- equivalent to s1
parse '.' . s3 . -- parsing a token that doesn't exist results in an empty string
strings = [s1, s2, s3, ' ']
loop s_ = 0 to strings.length - 1
say (Rexx s_).right(3)':\-'
select
w... | Give a code snippet in #NetRexx
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.
O... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brazilian_numbers | Brazilian numbers | Brazilian numbers are so called as they were first formally presented at the 1994 math Olympiad Olimpiada Iberoamericana de Matematica in Fortaleza, Brazil.
Brazilian numbers are defined as:
The set of positive integer numbers where each number N has at least one natural number B where 1 < B < N-1 where the represent... | #C.2B.2B | C++ | #include <iostream>
bool sameDigits(int n, int b) {
int f = n % b;
while ((n /= b) > 0) {
if (n % b != f) {
return false;
}
}
return true;
}
bool isBrazilian(int n) {
if (n < 7) return false;
if (n % 2 == 0)return true;
for (int b = 2; b < n - 1; b++) {
... | Give a code snippet in #C.2B.2B
Brazilian numbers are so called as they were first formally presented at the 1994 math Olympiad Olimpiada Iberoamericana de Matematica in Fortaleza, Brazil.
Brazilian numbers are defined as:
The set of positive integer numbers where each number N has at least one natural number B wher... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_literals,_with_continuations | Long literals, with continuations | This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
The literal is to be in the form ... | #Kotlin | Kotlin | import java.time.Instant
const val elementsChunk = """
hydrogen helium lithium beryllium
boron carbon nitrogen oxygen
fluorine neon sodium magnesium
aluminum silicon phosphorous sulfur
chlorine argon potassium calcium
scandium titanium... | Give a code snippet in #Kotlin
This task is about writing a computer program that has long literals (character
literals that may require specifying the words/tokens on more than one (source)
line, either with continuations or some other method, such as abutments or
concatenations (or some other mechanisms).
T... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitcoin/address_validation | Bitcoin/address validation | Bitcoin/address validation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Write a program that takes a bitcoin address as argument,
and checks whether or not this address is valid.
A bitcoin address uses a base58 encoding, which uses an alphabet of th... | #Perl | Perl | my @b58 = qw{
1 2 3 4 5 6 7 8 9
A B C D E F G H J K L M N P Q R S T U V W X Y Z
a b c d e f g h i j k m n o p q r s t u v w x y z
};
my %b58 = map { $b58[$_] => $_ } 0 .. 57;
sub unbase58 {
use integer;
my @out;
my $azeroes = length($1) if $_[0] =~ /^(1*)/;
for my $c ( map { $b58{$... | Give a code snippet in #Perl
Bitcoin/address validation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Write a program that takes a bitcoin address as argument,
and checks whether or not this address is valid.
A bitcoin address uses a base58 encoding... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Special_variables | Special variables | Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| #XLISP | XLISP | *PACKAGE*
*READTABLE*
*ERROR-HANDLER*
*UNBOUND-HANDLER*
*LOAD-PATH*
*STANDARD-INPUT*
*STANDARD-OUTPUT*
*ERROR-OUTPUT*
*FIXNUM-FORMAT*
*HEXNUM-FORMAT*
*FLONUM-FORMAT*
*PRINT-CASE*
*SOFTWARE-TYPE*
T ; bound to #T
NIL ; bound to '()
OBJECT
CLASS | Give a code snippet in #XLISP
Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_control_codes_and_extended_characters_from_a_string | Strip control codes and extended characters from a string | Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and extended characters stripped
In ASCII, the control codes ... | #jq | jq | def strip_control_codes:
explode | map(select(. > 31 and . != 127)) | implode;
def strip_extended_characters:
explode | map(select(31 < . and . < 127)) | implode; | Give a code snippet in #jq
Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and extended characters stripped
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Image_noise | Image noise | Generate a random black and white 320x240 image continuously,
showing FPS (frames per second).
A sample image
| #C.23 | C# | using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Drawing.Imaging;
using System.Linq;
using System.Runtime.InteropServices;
using System.Windows.Forms;
class Program
{
static Size size = new Size(320, 240);
static Rectangle rectsize = new Rectangle... | Give a code snippet in #C.23
Generate a random black and white 320x240 image continuously,
showing FPS (frames per second).
A sample image
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_operations | Bitwise operations |
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 |... | #Z80_Assembly | Z80 Assembly | LD A,&05
AND &1F ;0x05 & 0x1F | Give a code snippet in #Z80_Assembly
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 Oper... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sieve_of_Eratosthenes | Sieve of Eratosthenes | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed... | #JavaScript | JavaScript | function eratosthenes(limit) {
var primes = [];
if (limit >= 2) {
var sqrtlmt = Math.sqrt(limit) - 2;
var nums = new Array(); // start with an empty Array...
for (var i = 2; i <= limit; i++) // and
nums.push(i); // only initialize the Array once...
for (var i = 0; i <... | Give a code snippet in #JavaScript
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthene... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_an_object_method | Call an object method | In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static or class method, and an instance m... | #Fortran | Fortran |
! type declaration
type my_type
contains
procedure, pass :: method1
procedure, pass, pointer :: method2
end type my_type
! declare object of type my_type
type(my_type) :: mytype_object
!static call
call mytype_object%method1() ! call method1 defined as subroutine
!instance?
mytype_object%method2() ! call metho... | Give a code snippet in #Fortran
In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static o... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pick_random_element | Pick random element | Demonstrate how to pick a random element from a list.
| #XBS | XBS | set Array = ["Hello","World",1,2,3];
log(Array[rnd(0,?Array-1)]); | Give a code snippet in #XBS
Demonstrate how to pick a random element from a list.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_control_codes_and_extended_characters_from_a_string | Strip control codes and extended characters from a string | Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and extended characters stripped
In ASCII, the control codes ... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | stripCtrl[x_]:=StringJoin[Select[Characters[x],
MemberQ[CharacterRange["!","~"]~Join~Characters[FromCharacterCode[Range[128,255]]],#]&]]
stripCtrlExt[x_]:=StringJoin[Select[Characters[x],
MemberQ[CharacterRange["!","~"],#]&]] | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Strip control codes and extended characters from a string.
The solution should demonstrate how to achieve each of the following results:
a string with control codes stripped (but extended characters not stripped)
a string with control codes and ext... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Permutations/Rank_of_a_permutation | Permutations/Rank of a permutation | A particular ranking of a permutation associates an integer with a particular ordering of all the permutations of a set of distinct items.
For our purposes the ranking will assign integers
0..
(
n
!
−
1
)
{\displaystyle 0..(n!-1)}
to an ordering of all the permutations of the integers
0..
(
n
−
1
)
{\disp... | #Haskell | Haskell | fact :: Int -> Int
fact n = product [1 .. n]
-- Always assume elements are unique.
rankPerm [] _ = []
rankPerm list n = c : rankPerm (a ++ b) r
where
(q, r) = n `divMod` fact (length list - 1)
(a, c:b) = splitAt q list
permRank [] = 0
permRank (x:xs) = length (filter (< x) xs) * fact (length xs) + permR... | Give a code snippet in #Haskell
A particular ranking of a permutation associates an integer with a particular ordering of all the permutations of a set of distinct items.
For our purposes the ranking will assign integers
0..
(
n
!
−
1
)
{\displaystyle 0..(n!-1)}
to an ordering of all the permutations of the in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/First_power_of_2_that_has_leading_decimal_digits_of_12 | First power of 2 that has leading decimal digits of 12 | (This task is taken from a Project Euler problem.)
(All numbers herein are expressed in base ten.)
27 = 128 and 7 is
the first power of 2 whose leading decimal digits are 12.
The next power of 2 whose leading decimal digits
are 12 is 80,
280 = 1208925819614629174706176.
Define ... | #Wren | Wren | import "/fmt" for Fmt
import "/math" for Math
var ld10 = Math.ln2 / Math.ln10
var p = Fn.new { |L, n|
var i = L
var digits = 1
while (i >= 10) {
digits = digits * 10
i = (i/10).floor
}
var count = 0
i = 0
while (count < n) {
var e = (Math.ln10 * (i * ld10).fractio... | Give a code snippet in #Wren
(This task is taken from a Project Euler problem.)
(All numbers herein are expressed in base ten.)
27 = 128 and 7 is
the first power of 2 whose leading decimal digits are 12.
The next power of 2 whose leading decimal digits
are 12 is 80,
280 = 1208925... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cramer%27s_rule | Cramer's rule | linear algebra
Cramer's rule
system of linear equations
Given
{
a
1
x
+
b
1
y
+
c
1
z
=
d
1
a
2
x
+
b
2
y
+
c
2
z
=
d
2
a
3
x
+
b
3
y
+
c
3
z
=
d
3
{\displaystyle \left\{{\begin{matrix}a_{1}x+b_{1}y+c_{1}z&={\color {red}d_{1... | #D | D | import std.array : array, uninitializedArray;
import std.range : iota;
import std.stdio : writeln;
import std.typecons : tuple;
alias vector = double[4];
alias matrix = vector[4];
auto johnsonTrotter(int n) {
auto p = iota(n).array;
auto q = iota(n).array;
auto d = uninitializedArray!(int[])(n);
d[]... | Give a code snippet in #D
linear algebra
Cramer's rule
system of linear equations
Given
{
a
1
x
+
b
1
y
+
c
1
z
=
d
1
a
2
x
+
b
2
y
+
c
2
z
=
d
2
a
3
x
+
b
3
y
+
c
3
z
=
d
3
{\displaystyle \left\{{\begin{matrix}a_{1}x+b_{1}... | christopher/rosetta-code | |
http://rosettacode.org/wiki/IBAN | IBAN |
This page uses content from Wikipedia. The original article was at IBAN. 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 International Bank Account Number (IBAN) is an internationally agree... | #Racket | Racket | #lang racket
(define lens
'([AL 28] [AD 24] [AT 20] [AZ 28] [BH 22] [BE 16] [BA 20] [BR 29] [BG 22]
[CR 21] [HR 21] [CY 28] [CZ 24] [DK 18] [DO 28] [EE 20] [FO 18] [FI 18]
[FR 27] [GE 22] [DE 22] [GI 23] [GR 27] [GL 18] [GT 28] [HU 28] [IS 26]
[IE 22] [IL 23] [IT 27] [KZ 20] [KW 30] [LV 21] [LB 28] [LI 21... | Give a code snippet in #Racket
This page uses content from Wikipedia. The original article was at IBAN. 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 International Bank Account Number (IBA... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_comments_from_a_string | Strip comments from a string | Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
Whitespace debacle: There is s... | #Julia | Julia |
using Printf
function striplinecomment(a::String, cchars::String="#;")
b = strip(a)
0 < length(cchars) || return b
for c in cchars
r = Regex(@sprintf "\\%c.*" c)
b = replace(b, r => "")
end
strip(b)
end
tests = ("apples, pears # and bananas",
"apples, pears ; and banan... | Give a code snippet in #Julia
Strip comments from a string
You are encouraged to solve this task according to the task description, using any language you may know.
The task is to remove text that follow any of a set of comment markers, (in these examples either a hash or a semicolon) from a string or input line.
W... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Symmetric_difference | Symmetric difference | Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{\displaystyle (A\cup B)\setminus (A... | #BBC_BASIC | BBC BASIC | DIM list$(4)
list$() = "Bob", "Jim", "John", "Mary", "Serena"
setA% = %11101
PRINT "Set A: " FNlistset(list$(), setA%)
setB% = %01111
PRINT "Set B: " FNlistset(list$(), setB%)
REM Compute symmetric difference:
setC% = setA% EOR setB%
PRINT '"Symmetric difference... | Give a code snippet in #BBC_BASIC
Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parsing/Shunting-yard_algorithm | Parsing/Shunting-yard algorithm | Task
Given the operator characteristics and input from the Shunting-yard algorithm page and tables, use the algorithm to show the changes in the operator stack and RPN output
as each individual token is processed.
Assume an input of a correct, space separated, string of tokens representing an infix expression
Gener... | #Phix | Phix | with javascript_semantics
bool show_workings = true
constant operators = {"^","*","/","+","-"},
precedence = { 4, 3, 3, 2, 2 }
procedure shunting_yard(string infix, rpn)
string res = "", sep = "", stack_top
sequence stack = {},
ops = split(substitute_all(infix,{"(",")"},{" ( "," ... | Give a code snippet in #Phix
Task
Given the operator characteristics and input from the Shunting-yard algorithm page and tables, use the algorithm to show the changes in the operator stack and RPN output
as each individual token is processed.
Assume an input of a correct, space separated, string of tokens represent... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anagrams/Deranged_anagrams | Anagrams/Deranged anagrams | Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.
Task[edit]
Use the word list at uni... | #Prolog | Prolog | longest_deranged_anagram :-
http_open('http://www.puzzlers.org/pub/wordlists/unixdict.txt',In,[]),
read_file(In, [], Out),
close(In),
msort(Out, MOut),
group_pairs_by_key(MOut, GPL),
map_list_to_pairs(compute_len, GPL, NGPL),
predsort(my_compare, NGPL, GPLSort),
search_derangement(GPLSort).
% order tuples t... | Give a code snippet in #Prolog
Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.
Tas... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dot_product | Dot product | Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1]
If implementing the dot ... | #SQL | SQL | SELECT i, k, SUM(A.N*B.N) AS N
FROM A INNER JOIN B ON A.j=B.j
GROUP BY i, k | Give a code snippet in #SQL
Task
Create a function/use an in-built function, to compute the dot product, also known as the scalar product of two vectors.
If possible, make the vectors of arbitrary length.
As an example, compute the dot product of the vectors:
[1, 3, -5] and
[4, -2, -1] ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knapsack_problem/Bounded | Knapsack problem/Bounded | A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature. So he needs some items during the trip. Food, clothing, etc. He has a good knapsack for carrying the things, but he knows that he can carry only 4 kg weight in his knapsack, because th... | #MiniZinc | MiniZinc |
%Solve Knapsack Problem Bounded. Nigel Galloway, Octoer 12th., 2020.
enum Items={map,compass,water,sandwich,glucose,tin,banana,apple,cheese,beer,suntan_cream,camera,t_shirt,trousers,umbrella,waterproof_trousers,waterproof_overclothes,note_case,sunglasses,towel,socks,book};
array[Items] of int: weight =[9,13,153,50,1... | Give a code snippet in #MiniZinc
A tourist wants to make a good trip at the weekend with his friends.
They will go to the mountains to see the wonders of nature. So he needs some items during the trip. Food, clothing, etc. He has a good knapsack for carrying the things, but he knows that he can carry only 4 kg ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Old_lady_swallowed_a_fly | Old lady swallowed a fly | Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identical output.
Other tasks related to st... | #Icon_and_Unicon | Icon and Unicon | procedure main() #: There Was An Old Lady Lyrics
verse := table() # arglists for printf - [1] long asides and [2] terse joiners
verse["bird"] := [["%s,\nQuite absurd, %s %s;\n",1,2,1],["%s,\n",1]]
verse["cat"] := [["%s,\nFancy that, %s %s;\n",1,2,1],["%s,\n",1]]
verse["dog"] := [["%s,\nWhat a hog, %s %s;\... | Give a code snippet in #Icon_and_Unicon
Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
... | #BCPL | BCPL | get "libhdr"
manifest $( SIZE = 1 << 4 $)
let start() be
$( for y = SIZE-1 to 0 by -1 do
$( for i=1 to y do wrch(' ')
for x=0 to SIZE-y-1 do
writes((x & y) ~= 0 -> " ", "** ")
wrch('*N')
$)
$) | Give a code snippet in #BCPL
Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program defList.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM64.... | Give a code snippet in #AArch64_Assembly
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same 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 the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #Standard_ML | Standard ML |
datatype result=allSame | difference of string*char*int ;
val chkstring = fn input =>
let
val rec chk = fn ([],n) => allSame
| ([x],n) => allSame
| (x::y::t,n)=> if x=y then chk (y::t,n+1)
else difference (Int.fmt StringCvt.HEX(Char.ord(y)),y,n)
in
( ... | Give a code snippet in #Standard_ML
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 the same
indicate if or which character is different from the previous character
display... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bioinformatics/Sequence_mutation | Bioinformatics/Sequence mutation | Task
Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by:
Choosing a random base position in the sequence.
Mutate the sequence by doing one of either:
Swap the base at that position by changing it to one of A, C, G, or T. (which has a chance o... | #Java | Java | import java.util.Arrays;
import java.util.Random;
public class SequenceMutation {
public static void main(String[] args) {
SequenceMutation sm = new SequenceMutation();
sm.setWeight(OP_CHANGE, 3);
String sequence = sm.generateSequence(250);
System.out.println("Initial sequence:");
... | Give a code snippet in #Java
Task
Given a string of characters A, C, G, and T representing a DNA sequence write a routine to mutate the sequence, (string) by:
Choosing a random base position in the sequence.
Mutate the sequence by doing one of either:
Swap the base at that position by changing it to one of A, C, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Interactive_programming_(repl) | Interactive programming (repl) | Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.
Task
Show how to start this... | #Maxima | Maxima | (%i1) f(a, b, c) := sconcat(a, c, c, b)$
(%i2) f("Rosetta", "Code", ":");
(%o2) "Rosetta::Code" | Give a code snippet in #Maxima
Many language implementations come with an interactive mode.
This is a command-line interpreter that reads lines from the user and evaluates these lines as statements or expressions.
An interactive mode may also be known as a command mode, a read-eval-print loop (REPL), or a shell.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Downward_for | Loops/Downward for | Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop body... | #Mercury | Mercury | :- module loops_downward_for.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is det.
:- implementation.
:- import_module int.
main(!IO) :-
Print = (pred(I::in, !.IO::di, !:IO::uo) is det :-
io.write_int(I, !IO), io.nl(!IO)
),
int.fold_down(Print, 1, 10, !IO). | Give a code snippet in #Mercury
Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Incr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Amb | Amb | Define and give an example of the Amb operator.
The Amb operator (short for "ambiguous") expresses nondeterminism. This doesn't refer to randomness (as in "nondeterministic universe") but is closely related to the term as it is used in automata theory ("non-deterministic finite automaton").
The Amb operator takes a v... | #Mercury | Mercury | :- module amb.
:- interface.
:- import_module io.
:- pred main(io::di, io::uo) is cc_multi.
:- implementation.
:- import_module list, string, char, int.
main(!IO) :-
( solution(S) -> io.write_string(S, !IO), io.nl(!IO)
; io.write_string("No solutions found :-(\n", !IO) ).
:- pred solution(string::ou... | Give a code snippet in #Mercury
Define and give an example of the Amb operator.
The Amb operator (short for "ambiguous") expresses nondeterminism. This doesn't refer to randomness (as in "nondeterministic universe") but is closely related to the term as it is used in automata theory ("non-deterministic finite automat... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Brace_expansion | Brace expansion | Brace expansion is a type of parameter expansion made popular by Unix shells, where it allows users to specify multiple similar string parameters without having to type them all out. E.g. the parameter enable_{audio,video} would be interpreted as if both enable_audio and enable_video had been specified.
Task[edit]
W... | #Prolog | Prolog |
sym(',', commalist) --> ['\\',','], !.
sym(H, Context) --> [H], { not(H = '{'; H = '}'), (Context = commalist -> not(H = ','); true) }.
syms([H|T], Context) --> sym(H, Context), !, syms(T, Context).
syms([], _) --> [].
symbol(Symbol, Context) --> syms(Syms,Context), {atom_chars(Symbol, Syms)}.
... | Give a code snippet in #Prolog
Brace expansion is a type of parameter expansion made popular by Unix shells, where it allows users to specify multiple similar string parameters without having to type them all out. E.g. the parameter enable_{audio,video} would be interpreted as if both enable_audio and enable_video had... | 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
... | #11l | 11l | F partial(f, g)
F fg(x)
R @f(@g, x)
R fg
F main()
F ffs(f, x)
R x.map(a -> @f(a))
F f1(a) {R a * 2}
F f2(a) {R a * a}
V fsf1 = partial(ffs, f1)
V fsf2 = partial(ffs, f2)
print(fsf1([1, 2, 3, 4]))
print(fsf2([1, 2, 3, 4]))
main() | Give a code snippet in #11l
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.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Parallel_brute_force | Parallel brute force | Task
Find, through brute force, the five-letter passwords corresponding with the following SHA-256 hashes:
1. 1115dd800feaacefdf481f1f9070374a2a81e27880f187396db67958b207cbad
2. 3a7bd3e2360a3d29eea436fcfb7e44c735d117c42d1c1835420b6b9942dd4f1b
3. 74e1bb62f8dabb8125a58852b63bdf6eaef667cb56ac7f7cdba6d7305c50a22f
Your p... | #Scala | Scala | import java.security.MessageDigest
import scala.collection.parallel.immutable.ParVector
object EncryptionCracker {
def main(args: Array[String]): Unit = {
val hash1 = "1115dd800feaacefdf481f1f9070374a2a81e27880f187396db67958b207cbad"
val hash2 = "3a7bd3e2360a3d29eea436fcfb7e44c735d117c42d1c1835420b6b9942d... | Give a code snippet in #Scala
Task
Find, through brute force, the five-letter passwords corresponding with the following SHA-256 hashes:
1. 1115dd800feaacefdf481f1f9070374a2a81e27880f187396db67958b207cbad
2. 3a7bd3e2360a3d29eea436fcfb7e44c735d117c42d1c1835420b6b9942dd4f1b
3. 74e1bb62f8dabb8125a58852b63bdf6eaef667cb5... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_append | String append |
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 |... | #Tcl | Tcl | set s "he"
set s "${s}llo wo"; # The braces distinguish varname from text to concatenate
append s "rld"
puts $s | Give a code snippet in #Tcl
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
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_two_triangles_overlap | Determine if two triangles overlap | Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) and (-10,0),(-5,0),(-1,6)... | #Scala | Scala | object Overlap {
type Point = (Double, Double)
class Triangle(var p1: Point, var p2: Point, var p3: Point) {
override def toString: String = s"Triangle: $p1, $p2, $p3"
}
def det2D(t: Triangle): Double = {
val (p1, p2, p3) = (t.p1, t.p2, t.p3)
p1._1 * (p2._2 - p3._2) +
p2._1 * (p3._2 - p1._... | Give a code snippet in #Scala
Determining if two triangles in the same plane overlap is an important topic in collision detection.
Task
Determine which of these pairs of triangles overlap in 2D:
(0,0),(5,0),(0,5) and (0,0),(5,0),(0,6)
(0,0),(0,5),(5,0) and (0,0),(0,5),(5,0)
(0,0),(5,0),(0,5) ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Mean_time_of_day | Averages/Mean time of day | Task[edit]
A particular activity of bats occurs at these times of the day:
23:00:17, 23:40:20, 00:12:45, 00:17:19
Using the idea that there are twenty-four hours in a day,
which is analogous to there being 360 degrees in a circle,
map times of day to and from angles;
and using the ideas of Averages/Mean angle
compute ... | #BBC_BASIC | BBC BASIC | nTimes% = 4
DATA 23:00:17, 23:40:20, 00:12:45, 00:17:19
DIM angles(nTimes%-1)
FOR N% = 0 TO nTimes%-1
READ tim$
angles(N%) = FNtimetoangle(tim$)
NEXT
PRINT "Mean time is " FNangletotime(FNmeanangle(angles(), nTimes%))
END
DEF FNtimetoangle(t$)
LO... | Give a code snippet in #BBC_BASIC
Task[edit]
A particular activity of bats occurs at these times of the day:
23:00:17, 23:40:20, 00:12:45, 00:17:19
Using the idea that there are twenty-four hours in a day,
which is analogous to there being 360 degrees in a circle,
map times of day to and from angles;
and using the id... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sieve_of_Eratosthenes | Sieve of Eratosthenes | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed... | #BQN | BQN | Primes ← {
𝕩≤2 ? ↕0 ; # No primes below 2
p ← 𝕊⌈√n←𝕩 # Initial primes by recursion
b ← 2≤↕n # Initial sieve: no 0 or 1
E ← {↕∘⌈⌾((𝕩×𝕩+⊢)⁼)n} # Multiples of 𝕩 under n, starting at 𝕩×𝕩
/ b E⊸{0¨⌾(𝕨⊸⊏)𝕩}´ p # Cross them out
} | Give a code snippet in #BQN
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes alg... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pythagorean_triples | Pythagorean triples | A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\displaystyle a,b,c}
are co-prime,... | #Elixir | Elixir | defmodule RC do
def count_triples(limit), do: count_triples(limit,3,4,5)
defp count_triples(limit, a, b, c) when limit<(a+b+c), do: {0,0}
defp count_triples(limit, a, b, c) do
{p1, t1} = count_triples(limit, a-2*b+2*c, 2*a-b+2*c, 2*a-2*b+3*c)
{p2, t2} = count_triples(limit, a+2*b+2*c, 2*a+b+2*c, 2*a+2*b... | Give a code snippet in #Elixir
A Pythagorean triple is defined as three positive integers
(
a
,
b
,
c
)
{\displaystyle (a,b,c)}
where
a
<
b
<
c
{\displaystyle a<b<c}
, and
a
2
+
b
2
=
c
2
.
{\displaystyle a^{2}+b^{2}=c^{2}.}
They are called primitive triples if
a
,
b
,
c
{\dis... | christopher/rosetta-code | |
http://rosettacode.org/wiki/First-class_functions | First-class functions | A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming:
Create new functions from preexisting functions at run-time
Store functions in collections
Use functions as arguments to other functions
Use functions as retu... | #Icon_and_Unicon | Icon and Unicon | link compose
procedure main(arglist)
fun := [sin,cos,cube]
inv := [asin,acos,cuberoot]
x := 0.5
every i := 1 to *inv do
write("f(",x,") := ", compose(inv[i],fun[i])(x))
end
procedure cube(x)
return x*x*x
end
procedure cuberoot(x)
return x ^ (1./3)
end | Give a code snippet in #Icon_and_Unicon
A language has first-class functions if it can do each of the following without recursively invoking a compiler or interpreter or otherwise metaprogramming:
Create new functions from preexisting functions at run-time
Store functions in collections
Use functions as arguments ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anagrams/Deranged_anagrams | Anagrams/Deranged anagrams | Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.
Task[edit]
Use the word list at uni... | #AppleScript | AppleScript | use AppleScript version "2.3.1" -- OS X 10.9 (Mavericks) or later — for these 'use' commands!
-- Uses the customisable AppleScript-coded sort shown at <https://macscripter.net/viewtopic.php?pid=194430#p194430>.
-- It's assumed scripters will know how and where to install it as a library.
use sorter : script "Custom Ite... | Give a code snippet in #AppleScript
Two or more words are said to be anagrams if they have the same characters, but in a different order.
By analogy with derangements we define a deranged anagram as two words with the same characters, but in which the same character does not appear in the same position in both words.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Old_lady_swallowed_a_fly | Old lady swallowed a fly | Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identical output.
Other tasks related to st... | #Lua | Lua | animals = {"fly", "spider", "bird", "cat","dog", "goat", "cow", "horse"}
phrases = {
"",
"That wriggled and jiggled and tickled inside her",
"How absurd to swallow a bird",
"Fancy that to swallow a cat",
"What a hog, to swallow a dog",
"She just opened her throat and swallowed a goat",
"I do... | Give a code snippet in #Lua
Task
Present a program which emits the lyrics to the song I Knew an Old Lady Who Swallowed a Fly, taking advantage of the repetitive structure of the song's lyrics.
This song has multiple versions with slightly different lyrics, so all these programs might not emit identical output.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Standard_error | Hello world/Standard error | Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out".
The error messages print to ... | #Lingo | Lingo | -- print to standard error
stdErr("Goodbye, World!", TRUE)
-- print to the Windows debug console (shown in realtime e.g. in Systernal's DebugView)
dbgPrint("Goodbye, World!") | Give a code snippet in #Lingo
Hello world/Standard error is part of Short Circuit's Console Program Basics selection.
A common practice in computing is to send error messages
to a different output stream than normal text console messages.
The normal messages print to what is called "standard output" or "standard out"... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_numbers | Perfect numbers | Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including itself).
Note: The faster Luca... | #Common_Lisp | Common Lisp | (defun perfectp (n)
(= n (loop for i from 1 below n when (= 0 (mod n i)) sum i))) | Give a code snippet in #Common_Lisp
Write a function which says whether a number is perfect.
A perfect number is a positive integer that is the sum of its proper positive divisors excluding the number itself.
Equivalently, a perfect number is a number that is half the sum of all of its positive divisors (including ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bulls_and_cows/Player | Bulls and cows/Player | Task
Write a player of the Bulls and Cows game, rather than a scorer. The player should give intermediate answers that respect the scores to previous attempts.
One method is to generate a list of all possible numbers that could be the answer, then to prune the list by keeping only those numbers that would give an equ... | #BBC_BASIC | BBC BASIC | secret$ = ""
REPEAT
c$ = CHR$(&30 + RND(9))
IF INSTR(secret$, c$) = 0 secret$ += c$
UNTIL LEN(secret$) = 4
FOR i% = 1234 TO 9876
possible$ += STR$(i%)
NEXT
PRINT "Guess a four-digit number with no digit used twice."
guesses% = 0
REPEAT
... | Give a code snippet in #BBC_BASIC
Task
Write a player of the Bulls and Cows game, rather than a scorer. The player should give intermediate answers that respect the scores to previous attempts.
One method is to generate a list of all possible numbers that could be the answer, then to prune the list by keeping only t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Web_scraping | Web scraping | Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page's talk page.
If possible,... | #Oz | Oz | declare
[Regex] = {Module.link ['x-oz://contrib/regex']}
fun {GetPage Url}
F = {New Open.file init(url:Url)}
Contents = {F read(list:$ size:all)}
in
{F close}
Contents
end
fun {GetDateString Doc}
case {Regex.search "<BR>([A-Za-z0-9:., ]+ UTC)" Doc}
of match(1:S#E ...) then {L... | Give a code snippet in #Oz
Task
Create a program that downloads the time from this URL: http://tycho.usno.navy.mil/cgi-bin/timer.pl and then prints the current UTC time by extracting just the UTC time from the web page's HTML. Alternatively, if the above url is not working, grab the first date/time off this page'... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Twelve_statements | Twelve statements | This puzzle is borrowed from math-frolic.blogspot.
Given the following twelve statements, which of them are true?
1. This is a numbered list of twelve statements.
2. Exactly 3 of the last 6 statements are true.
3. Exactly 2 of the even-numbered statements are true.
4. If statement 5 is true, then statemen... | #uBasic.2F4tH | uBasic/4tH | S = 12
For T = 0 To (2^S)-1
For I = 1 To 12
Push T, 2^(I-1) : Gosub 100
@(I) = Pop() # 0
Next
REM Test consistency:
@(101) = @(1) = (S = 12)
@(102) = @(2) = ((@(7)+@(8)+@(9)+@(10)+@(11)+@(12)) = 3)
@(103) = @(3) = ((@(2)+@(4)+@(6)+@(8)+@(10)+@(12)) = 2)
@(104) = @(4) = ((@(5)=0) + (@... | Give a code snippet in #uBasic.2F4tH
This puzzle is borrowed from math-frolic.blogspot.
Given the following twelve statements, which of them are true?
1. This is a numbered list of twelve statements.
2. Exactly 3 of the last 6 statements are true.
3. Exactly 2 of the even-numbered statements are true.
4. ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exceptions/Catch_an_exception_thrown_in_a_nested_call | Exceptions/Catch an exception thrown in a nested call | Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrange for function baz to rais... | #Java | Java | class U0 extends Exception { }
class U1 extends Exception { }
public class ExceptionsTest {
public static void foo() throws U1 {
for (int i = 0; i <= 1; i++) {
try {
bar(i);
} catch (U0 e) {
System.out.println("Function foo caught exception U0");
... | Give a code snippet in #Java
Show how to create a user-defined exception and show how to catch an exception raised from several nested calls away.
Create two user-defined exceptions, U0 and U1.
Have function foo call function bar twice.
Have function bar call function baz.
Arrang... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Numbers_with_equal_rises_and_falls | Numbers with equal rises and falls | When a number is written in base 10, adjacent digits may "rise" or "fall" as the number is read (usually from left to right).
Definition
Given the decimal digits of the number are written as a series d:
A rise is an index i such that d(i) < d(i+1)
A fall is an index i such that ... | #REXX | REXX | /*REXX pgm finds and displays N numbers that have an equal number of rises and falls,*/
parse arg n . /*obtain optional argument from the CL.*/
if n=='' | n=="," then n= 200 /*Not specified? Then use the default.*/
append= n>0 ... | Give a code snippet in #REXX
When a number is written in base 10, adjacent digits may "rise" or "fall" as the number is read (usually from left to right).
Definition
Given the decimal digits of the number are written as a series d:
A rise is an index i such that d(i) < d(i+1)
A fall ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/The_Twelve_Days_of_Christmas | The Twelve Days of Christmas | Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations:
Metrics
Array length
Stri... | #C.23 | C# | using System;
public class TwelveDaysOfChristmas {
public static void Main() {
string[] days = new string[12] {
"first", "second", "third", "fourth", "fifth", "sixth", "seventh", "eighth", "ninth",
"tenth", "eleventh", "twelfth",
};
string[] gifts = new string... | Give a code snippet in #C.23
Task
Write a program that outputs the lyrics of the Christmas carol The Twelve Days of Christmas.
The lyrics can be found here.
(You must reproduce the words in the correct order, but case, format, and punctuation are left to your discretion.)
Other tasks related to string operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greyscale_bars/Display | Greyscale bars/Display | The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha... | #zkl | zkl | img:=PPM(640,480);
foreach q in ([0..3]){ //quarter of screen
n:=(8).shiftLeft(q); //number of bars
w:=640/n; //width of bar (pixels)
foreach b in ([0..n-1]){ //for each bar...
c:=(255.0/(n-1).toFloat() * (if(q.isOdd) n-1-b else b)).toInt();
c:=c.shiftLeft(16) + c.shiftLeft(8) + c; //R... | Give a code snippet in #zkl
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we hav... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Queue/Definition | Queue/Definition |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the order of insertion.
Operation... | #ATS | ATS | (*------------------------------------------------------------------*)
#define ATS_DYNLOADFLAG 0
#include "share/atspre_staload.hats"
staload UN = "prelude/SATS/unsafe.sats"
(*------------------------------------------------------------------*)
vtypedef queue_vt (vt : vt@ype+, n : int) =
(* A list that form... | Give a code snippet in #ATS
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Implement a FIFO queue.
Elements are added at one side and popped from the other in the ord... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Animate_a_pendulum | Animate a pendulum |
One good way of making an animation is by simulating a physical system and illustrating the variables in that system using a dynamically changing graphical display.
The classic such physical system is a simple gravity pendulum.
Task
Create a simple physical model of a pendulum and animate it.
| #Rust | Rust |
// using version 0.107.0 of piston_window
use piston_window::{clear, ellipse, line_from_to, PistonWindow, WindowSettings};
const PI: f64 = std::f64::consts::PI;
const WIDTH: u32 = 640;
const HEIGHT: u32 = 480;
const ANCHOR_X: f64 = WIDTH as f64 / 2. - 12.;
const ANCHOR_Y: f64 = HEIGHT as f64 / 4.;
const ANCHOR_EL... | Give a code snippet in #Rust
One good way of making an animation is by simulating a physical system and illustrating the variables in that system using a dynamically changing graphical display.
The classic such physical system is a simple gravity pendulum.
Task
Create a simple physical model of a pendulum and an... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Anti-primes | Anti-primes | The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| #D | D | import std.stdio;
int countDivisors(int n) {
if (n < 2) {
return 1;
}
int count = 2; // 1 and n
for (int i = 2; i <= n/2; ++i) {
if (n % i == 0) {
++count;
}
}
return count;
}
void main() {
int maxDiv, count;
writeln("The first 20 anti-primes are:"... | Give a code snippet in #D
The anti-primes
(or highly composite numbers, sequence A002182 in the OEIS)
are the natural numbers with more factors than any smaller than itself.
Task
Generate and show here, the first twenty anti-primes.
Related tasks
Factors of an integer
Sieve of Eratosthenes
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #REALbasic | REALbasic |
Function Multiply(a As Integer, b As Integer) As Integer
Return a * b
End Function
| Give a code snippet in #REALbasic
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-256 | SHA-256 | SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.
Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa542713965b785e5cc2f707d6468d7d1124cdfcf
| #Scala | Scala | object RosettaSHA256 extends App {
def MD5(s: String): String = {
// Besides "MD5", "SHA-256", and other hashes are available
val m = java.security.MessageDigest.getInstance("SHA-256").digest(s.getBytes("UTF-8"))
m.map("%02x".format(_)).mkString
}
assert(MD5("Rosetta code") == "764faf5c61ac315f149... | Give a code snippet in #Scala
SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.
Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa542713965b78... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pentomino_tiling | Pentomino tiling | A pentomino is a polyomino that consists of 5 squares. There are 12 pentomino shapes,
if you don't count rotations and reflections. Most pentominoes can form their own mirror image through
rotation, but some of them have to be flipped over.
I ... | #Visual_Basic_.NET | Visual Basic .NET | Module Module1
Dim symbols As Char() = "XYPFTVNLUZWI█".ToCharArray(),
nRows As Integer = 8, nCols As Integer = 8,
target As Integer = 12, blank As Integer = 12,
grid As Integer()() = New Integer(nRows - 1)() {},
placed As Boolean() = New Boolean(target - 1) {},
pens As List... | Give a code snippet in #Visual_Basic_.NET
A pentomino is a polyomino that consists of 5 squares. There are 12 pentomino shapes,
if you don't count rotations and reflections. Most pentominoes can form their own mirror image through
rotation, but some of them have to be flipped over.
I ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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 |... | #friendly_interactive_shell | friendly interactive shell | read a
read b
if test $a -gt $b
echo Greater
else if test $a -lt $b
echo Less
else if test $a -eq $b
echo Equal
end | Give a code snippet in #friendly_interactive_shell
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 |
Logic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_pixel | Draw a pixel | Task
Create a window and draw a pixel in it, subject to the following:
the window is 320 x 240
the color of the pixel must be red (255,0,0)
the position of the pixel is x = 100, y = 100 | #Icon_and_Unicon | Icon and Unicon | #
# draw-pixel.icn
#
procedure main()
&window := open("pixel", "g", "size=320,240")
Fg("#ff0000")
DrawPoint(100, 100)
Event()
end | Give a code snippet in #Icon_and_Unicon
Task
Create a window and draw a pixel in it, subject to the following:
the window is 320 x 240
the color of the pixel must be red (255,0,0)
the position of the pixel is x = 100, y = 100 | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calculating_the_value_of_e | Calculating the value of e | Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "float.s7i";
const float: EPSILON is 1.0e-15;
const proc: main is func
local
var integer: fact is 1;
var float: e is 2.0;
var float: e0 is 0.0;
var integer: n is 2;
begin
repeat
e0 := e;
fact *:= n;
incr(n);
e +:= 1.0 / flt(fact);
... | Give a code snippet in #Seed7
Task
Calculate the value of e.
(e is also known as Euler's number and Napier's constant.)
See details: Calculating the value of e
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For_with_a_specified_step | Loops/For with a specified step |
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop b... | #bc | bc | for (i = 2; i <= 10; i += 2) {
i
} | Give a code snippet in #bc
Task
Demonstrate a for-loop where the step-value is greater than one.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stem-and-leaf_plot | Stem-and-leaf plot | Create a well-formatted stem-and-leaf plot from the following data set, where the leaves are the last digits:
12 127 28 42 39 113 42 18 44 118 44 37 113 124 37 48 127 36 29 31 125 139 131 115 105 132 104 123 35 113 122 42 117 119 58 109 23 105 63 27 44 105 99 41 128 121 116 125 32 61 37 127 29 113 121 58 114 126 53 11... | #Go | Go | package main
import (
"fmt"
"sort"
"strconv"
"strings"
)
var data = `12 127 28 42` //...omitted...127 31 116 146`
func main() {
// load data into map
m := make(map[int][]string)
for _, s := range strings.Fields(data) {
if len(s) == 1 {
m[0] = append(m[0], s)
... | Give a code snippet in #Go
Create a well-formatted stem-and-leaf plot from the following data set, where the leaves are the last digits:
12 127 28 42 39 113 42 18 44 118 44 37 113 124 37 48 127 36 29 31 125 139 131 115 105 132 104 123 35 113 122 42 117 119 58 109 23 105 63 27 44 105 99 41 128 121 116 125 32 61 37 127... | christopher/rosetta-code |
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