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/Luhn_test_of_credit_card_numbers | Luhn test of credit card numbers | The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order of the digits in the number.
Tak... | #SPARK | SPARK | with Spark_IO;
--# inherit Spark_IO;
--# main_program;
procedure Luhn
--# global in out Spark_IO.Outputs;
--# derives Spark_IO.Outputs from *;
is
function Luhn_Test (Num : String) return Boolean
--# pre Num'Last <= 20;
is
Sum : Integer := 0;
Od : Boolean := True;
Int : Integer;
X ... | Give a code snippet in #SPARK
The Luhn test is used by some credit card companies to distinguish valid credit card numbers from what could be a random selection of digits.
Those companies using credit card numbers that can be validated by the Luhn test have numbers that pass the following test:
Reverse the order of... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ulam_spiral_(for_primes) | Ulam spiral (for primes) | An Ulam spiral (of primes) is a method of visualizing primes when expressed in a (normally counter-clockwise) outward spiral (usually starting at 1), constructed on a square grid, starting at the "center".
An Ulam spiral is also known as a prime spiral.
The first grid (green) is shown with sequential integers, ... | #Racket | Racket | #lang racket
(require (only-in math/number-theory prime?))
(define ((cell-fn n (start 1)) x y)
(let* ((y (- y (quotient n 2)))
(x (- x (quotient (sub1 n) 2)))
(l (* 2 (if (> (abs x) (abs y)) (abs x) (abs y))))
(d (if (>= y x) (+ (* l 3) x y) (- l x y))))
(+ (sqr (- l 1)) d start -1)))... | Give a code snippet in #Racket
An Ulam spiral (of primes) is a method of visualizing primes when expressed in a (normally counter-clockwise) outward spiral (usually starting at 1), constructed on a square grid, starting at the "center".
An Ulam spiral is also known as a prime spiral.
The first grid (green) is sh... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Casting_out_nines | Casting out nines | Task (in three parts)
Part 1
Write a procedure (say
c
o
9
(
x
)
{\displaystyle {\mathit {co9}}(x)}
) which implements Casting Out Nines as described by returning the checksum for
x
{\displaystyle x}
. Demonstrate the procedure using the examples given there, or others you may consider lucky.
Par... | #Java | Java | import java.util.*;
import java.util.stream.IntStream;
public class CastingOutNines {
public static void main(String[] args) {
System.out.println(castOut(16, 1, 255));
System.out.println(castOut(10, 1, 99));
System.out.println(castOut(17, 1, 288));
}
static List<Integer> castOu... | Give a code snippet in #Java
Task (in three parts)
Part 1
Write a procedure (say
c
o
9
(
x
)
{\displaystyle {\mathit {co9}}(x)}
) which implements Casting Out Nines as described by returning the checksum for
x
{\displaystyle x}
. Demonstrate the procedure using the examples given there, or other... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_concatenation | String concatenation | String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string literal.
To illustrate the operat... | #Halon | Halon | echo "Hello" . "World " . 123; | Give a code snippet in #Halon
String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string lit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #J | J | double =: 2&*
halve =: %&2 NB. or the primitive -:
odd =: 2&|
ethiop =: +/@(odd@] # (double~ <@#)) (1>.<.@halve)^:a: | Give a code snippet in #J
Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_occurrences_of_a_substring | Count occurrences of a substring | Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
It should return an integer cou... | #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols nobinary
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method countSubstring(inStr, findStr) public static
return inStr.countstr(findStr)
-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~... | Give a code snippet in #NetRexx
Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Set_consolidation | Set consolidation | Given two sets of items then if any item is common to any set then the result of applying consolidation to those sets is a set of sets whose contents is:
The two input sets if no common item exists between the two input sets of items.
The single set that is the union of the two input sets if they share a common item... | #Sidef | Sidef | func consolidate() { [] }
func consolidate(this, *those) {
gather {
consolidate(those...).each { |that|
if (this & that) { this |= that }
else { take that }
}
take this;
}
}
enum |A="A", B, C, D, _E, F, G, H, I, _J, K|;
func format(ss) {
ss.map... | Give a code snippet in #Sidef
Given two sets of items then if any item is common to any set then the result of applying consolidation to those sets is a set of sets whose contents is:
The two input sets if no common item exists between the two input sets of items.
The single set that is the union of the two input s... | 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.
| #Julia | Julia | function checkdigit(n)
matrix = (
(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, 6, 9, 7, 2, 0, 1, 3, 4),
... | Give a code snippet in #Julia
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/XML/Output | XML/Output | Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks> element.
As an example, calling ... | #PicoLisp | PicoLisp | (load "@lib/xml.l")
(de characterRemarks (Names Remarks)
(xml
(cons
'CharacterRemarks
NIL
(mapcar
'((Name Remark)
(list 'Character (list (cons 'name Name)) Remark) )
Names
Remarks ) ) ) )
(characterRemarks
'("April" "Tam O'Sha... | Give a code snippet in #PicoLisp
Create a function that takes a list of character names and a list of corresponding remarks and returns an XML document of <Character> elements each with a name attributes and each enclosing its remarks.
All <Character> elements are to be enclosed in turn, in an outer <CharacterRemarks>... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #C.2B.2B | C++ | #include <iostream>
#include <fstream>
#include <string>
#include <iterator>
int main( )
{
if (std::ifstream infile("sample.txt"))
{
// construct string from iterator range
std::string fileData(std::istreambuf_iterator<char>(infile), std::istreambuf_iterator<char>());
cout << "File ... | Give a code snippet in #C.2B.2B
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished inc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Short-circuit_evaluation | Short-circuit evaluation | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable resources without side effects, an... | #Perl | Perl | sub a { print 'A'; return $_[0] }
sub b { print 'B'; return $_[0] }
# Test-driver
sub test {
for my $op ('&&','||') {
for (qw(1,1 1,0 0,1 0,0)) {
my ($x,$y) = /(.),(.)/;
print my $str = "a($x) $op b($y)", ': ';
eval $str; print "\n"; } }
}
# Test and display
test(); | Give a code snippet in #Perl
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Assume functions a and b return boolean values, and further, the execution of function b takes considerable reso... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pi | Pi |
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal sequence beginning 3.14159265 ...... | #AutoHotkey | AutoHotkey | #NoEnv
#SingleInstance, Force
SetBatchLines, -1
#Include mpl.ahk
dot:=".", i:=0
, MP_SET(q, "1")
, MP_SET(r, "0")
, MP_SET(t, "1")
, MP_SET(k, "1")
, MP_SET(n, "3")
, MP_SET(l, "3")
, MP_SET(ONE, "1")
, MP_SET(TWO, "2")
, MP_SET(THREE, "3")
, MP_SET(FOUR, "4")
, MP_SET(SEVEN, "7")
, MP_SET(TEN, "10")
Loop
{
MP_MUL(q... | Give a code snippet in #AutoHotkey
Create a program to continually calculate and output the next decimal digit of
π
{\displaystyle \pi }
(pi).
The program should continue forever (until it is aborted by the user) calculating and outputting each decimal digit in succession.
The output should be a decimal... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Minimum_multiple_of_m_where_digital_sum_equals_m | Minimum multiple of m where digital sum equals m | Generate the sequence a(n) when each element is the minimum integer multiple m such that the digit sum of n times m is equal to n.
Task
Find the first 40 elements of the sequence.
Stretch
Find the next 30 elements of the sequence.
See also
OEIS:A131382 - Minimal number m such that Sum_digits(n*m)=n
| #BASIC | BASIC | c = 0
n = 1
while c < 70
m = 1
while 1
nm = n*m
t = 0
while nm
t += nm mod 10
nm = floor(nm / 10)
end while
if t = n then exit while
m += 1
end while
c += 1
print rjust(string(m), 8); " ";
if c mod 10 = 0 then print
n += 1
end... | Give a code snippet in #BASIC
Generate the sequence a(n) when each element is the minimum integer multiple m such that the digit sum of n times m is equal to n.
Task
Find the first 40 elements of the sequence.
Stretch
Find the next 30 elements of the sequence.
See also
OEIS:A131382 - Minimal number m such th... | 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... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | b^^nnnn is a valid number in base b (with b ranging from 2 to 36) :
2^^1011
-> 11
36^^1011
-> 46693 | Give a code snippet in #Mathematica.2FWolfram_Language
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 functio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pointers_and_references | Pointers and references |
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 |... | #Oforth | Oforth |
::class Foo
::method init
expose x
x = 0
::attribute x
::routine somefunction
a = .Foo~new -- assigns a to point to a new Foo object
b = a -- b and a now point to the same object
a~x = 5 -- modifies the X variable inside the object pointer to by a
say b~x ... | Give a code snippet in #Oforth
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/CUSIP | CUSIP |
This page uses content from Wikipedia. The original article was at CUSIP. 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)
A CUSIP is a nine-character alphanumeric code that identifies a North A... | #Wren | Wren | var isCusip = Fn.new { |s|
if (s.count != 9) return false
var sum = 0
for (i in 0..7) {
var c = s[i].bytes[0]
var v
if (c >= 48 && c <= 57) { // '0' to '9'
v = c - 48
} else if (c >= 65 && c <= 90) { // 'A' to 'Z'
v = c - 55
} else if (s[i] == ... | Give a code snippet in #Wren
This page uses content from Wikipedia. The original article was at CUSIP. 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)
A CUSIP is a nine-character alphanumeric ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_an_HTML_table | Create an HTML table | Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled with sequential row numbers.
The... | #BBC_BASIC | BBC BASIC | ncols% = 3
nrows% = 4
*spool temp.htm
PRINT "<html><head></head><body>"
PRINT "<table border=1 cellpadding=10 cellspacing=0>"
FOR row% = 0 TO nrows%
IF row% = 0 THEN
PRINT "<tr><th></th>" ;
ELSE
PRINT "<tr><th>" ; row% "</th>" ;
ENDIF... | Give a code snippet in #BBC_BASIC
Create an HTML table.
The table body should have at least three rows of three columns.
Each of these three columns should be labelled "X", "Y", and "Z".
An extra column should be added at either the extreme left or the extreme right of the table that has no heading, but is filled... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Calkin-Wilf_sequence | Calkin-Wilf sequence | The Calkin-Wilf sequence contains every nonnegative rational number exactly once.
It can be calculated recursively as follows:
a1 = 1
an+1 = 1/(2⌊an⌋+1-an) for n > 1
Task part 1
Show on this page terms 1 through 20 of the Calkin-Wilf sequence.
To avoid floating point error, you may want to ... | #Ruby | Ruby | cw = Enumerator.new do |y|
y << a = 1.to_r
loop { y << a = 1/(2*a.floor + 1 - a) }
end
def term_num(rat)
num, den, res, pwr, dig = rat.numerator, rat.denominator, 0, 0, 1
while den > 0
num, (digit, den) = den, num.divmod(den)
digit.times do
res |= dig << pwr
pwr += 1
end
dig ^= 1... | Give a code snippet in #Ruby
The Calkin-Wilf sequence contains every nonnegative rational number exactly once.
It can be calculated recursively as follows:
a1 = 1
an+1 = 1/(2⌊an⌋+1-an) for n > 1
Task part 1
Show on this page terms 1 through 20 of the Calkin-Wilf sequence.
To avoid floating... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Square_but_not_cube | Square but not cube | Task
Show the first 30 positive integers which are squares but not cubes of such integers.
Optionally, show also the first 3 positive integers which are both squares and cubes, and mark them as such.
| #Python | Python | # nonCubeSquares :: Int -> [(Int, Bool)]
def nonCubeSquares(n):
upto = enumFromTo(1)
ns = upto(n)
setCubes = set(x ** 3 for x in ns)
ms = upto(n + len(set(x * x for x in ns).intersection(
setCubes
)))
return list(tuple([x * x, x in setCubes]) for x in ms)
# squareListing :: [(Int, Bo... | Give a code snippet in #Python
Task
Show the first 30 positive integers which are squares but not cubes of such integers.
Optionally, show also the first 3 positive integers which are both squares and cubes, and mark them as such.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Horizontal_sundial_calculations | Horizontal sundial calculations | Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit... | #LiveCode | LiveCode | on mouseUp
ask "Enter lng,lat,meridian"
if it is empty then exit mouseup
// -150.5, -4.95, -150.0
put item 1 of it into longitude
put item 2 of it into latitude
put item 3 of it into meridian
repeat with hour = 6 TO 18
put 15 *hour - longitude + meridian - 180 into hra
put ... | Give a code snippet in #LiveCode
Task
Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location.
For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Isl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_two-dimensional_array_at_runtime | Create a two-dimensional array at runtime |
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.
Get two integers from the user, then create a two-dimensional array where the two dimensions have the sizes given by those numbers, and which can be accessed ... | #C.2B.2B | C++ | #include <iostream>
int main()
{
// read values
int dim1, dim2;
std::cin >> dim1 >> dim2;
// create array
double* array_data = new double[dim1*dim2];
double** array = new double*[dim1];
for (int i = 0; i < dim1; ++i)
array[i] = array_data + dim2*i;
// write element
array[0][0] = 3.5;
// ... | Give a code snippet in #C.2B.2B
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.
Get two integers from the user, then create a two-dimensional array where the two dimensions have the sizes given by those nu... | 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
| #Python | Python | >>> import hashlib
>>> hashlib.sha256( "Rosetta code".encode() ).hexdigest()
'764faf5c61ac315f1497f9dfa542713965b785e5cc2f707d6468d7d1124cdfcf'
>>> | Give a code snippet in #Python
SHA-256 is the recommended stronger alternative to SHA-1. See FIPS PUB 180-4 for implementation details.
Either by using a dedicated library or implementing the algorithm in your language, show that the SHA-256 digest of the string "Rosetta code" is: 764faf5c61ac315f1497f9dfa542713965b7... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Temperature_conversion | Temperature conversion | There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 kelvin.
0 kelvin is absolute z... | #C | C | #include <stdio.h>
#include <stdlib.h>
double kelvinToCelsius(double k){
return k - 273.15;
}
double kelvinToFahrenheit(double k){
return k * 1.8 - 459.67;
}
double kelvinToRankine(double k){
return k * 1.8;
}
void convertKelvin(double kelvin) {
printf("K %.2f\n", kelvin);
printf("C %.2f\n", k... | Give a code snippet in #C
There are quite a number of temperature scales. For this task we will concentrate on four of the perhaps best-known ones:
Kelvin, Celsius, Fahrenheit, and Rankine.
The Celsius and Kelvin scales have the same magnitude, but different null points.
0 degrees Celsius corresponds to 273.15 kelv... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Pancake_sort | Sorting algorithms/Pancake sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #UNIX_Shell | UNIX Shell | #!/usr/bin/env bash
main() {
local stack
local -i n m i
if (( $# )); then
stack=("$@")
else
stack=($(printf '%s\n' {0..9} | shuf))
fi
print_stack 0 "${stack[@]}"
# start by looking at whole stack
(( n = ${#stack[@]} ))
# keep going until we're all sorted
while (( n > 0 )); do
# shr... | Give a code snippet in #UNIX_Shell
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 |
Qui... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Creation | Associative array/Creation | Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element ins... | #Lambdatalk | Lambdatalk |
1) a (currently) reduced set of functions:
HASH: [5] [H.lib, H.new, H.disp, H.get, H.set!]
2) building an associative array: {def H key value | ...}
{def capitals
{H.new nyk New York, United States |
lon London, United Kingdom |
par Paris, France |
mos Moscou, Russia }}
-> capitals
... | Give a code snippet in #Lambdatalk
Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/RIPEMD-160 | RIPEMD-160 | RIPEMD-160 is another hash function; it computes a 160-bit message digest.
There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160.
For padding the message, RIPEMD-160 acts like MD4 (RFC 1320).
Find the RIPEMD-160 message digest of a string of octets.
Use the ASCII encoded string “Rosetta Cod... | #Ruby | Ruby | require 'digest'
puts Digest::RMD160.hexdigest('Rosetta Code') | Give a code snippet in #Ruby
RIPEMD-160 is another hash function; it computes a 160-bit message digest.
There is a RIPEMD-160 home page, with test vectors and pseudocode for RIPEMD-160.
For padding the message, RIPEMD-160 acts like MD4 (RFC 1320).
Find the RIPEMD-160 message digest of a string of octets.
Use the ASC... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Magic_8-ball | Magic 8-ball | Task
Create Magic 8-Ball.
See details at: Magic 8-Ball.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C
Bioinformatics/base count
Count occurren... | #M2000_Interpreter | M2000 Interpreter |
Module Magic.8.Ball {
answers=("It is certain", "It is decidedly so", "Without a doubt", "Yes, definitely", "You may rely on it", "As I see it, yes", "Most likely", "Outlook good", "Signs point to yes", "Yes", "Reply hazy, try again", "Ask again later", "Better not tell you now", "Cannot predict now", "Concent... | Give a code snippet in #M2000_Interpreter
Task
Create Magic 8-Ball.
See details at: Magic 8-Ball.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
Word frequency
Letter frequency
Jewels and stones
I before E except after C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Truth_table | Truth table | A truth table is a display of the inputs to, and the output of a Boolean function organized as a table where each row gives one combination of input values and the corresponding value of the function.
Task
Input a Boolean function from the user as a string then calculate and print a formatted truth table for the g... | #Quackery | Quackery | [ stack ] is args ( --> s )
[ stack ] is results ( --> s )
[ stack ] is function ( --> s )
[ args share times
[ sp
2 /mod iff
[ char t ]
else
[ char f ]
emit ]
drop
say " |... | Give a code snippet in #Quackery
A truth table is a display of the inputs to, and the output of a Boolean function organized as a table where each row gives one combination of input values and the corresponding value of the function.
Task
Input a Boolean function from the user as a string then calculate and print... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Man_or_boy_test | Man or boy test | Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim of the test was to distinguis... | #BBC_BASIC | BBC BASIC | HIMEM = PAGE + 200000000 : REM Increase recursion depth
FOR k% = 0 TO 20
PRINT FNA(k%, ^FN1(), ^FN_1(), ^FN_1(), ^FN1(), ^FN0())
NEXT
END
DEF FNA(k%, x1%, x2%, x3%, x4%, x5%)
IF k% <= 0 THEN = FN(x4%)(x4%) + FN(x5%)(x5%)
LOCAL b{}
DIM b{fn%, k%, x1%, x2%, x3%,... | Give a code snippet in #BBC_BASIC
Man or boy test
You are encouraged to solve this task according to the task description, using any language you may know.
Background: The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. Th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Integer | Arithmetic/Integer |
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 |... | #Ruby | Ruby | puts 'Enter x and y'
x = gets.to_i # to check errors, use x=Integer(gets)
y = gets.to_i
puts "Sum: #{x+y}",
"Difference: #{x-y}",
"Product: #{x*y}",
"Quotient: #{x/y}", # truncates towards negative infinity
"Quotient: #{x.fdiv(y)}", # float
"Remainder: #{x%y}", # same sign as seco... | Give a code snippet in #Ruby
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SEDOLs | SEDOLs | Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
5852842
B0YBKT7
B000300
Extra credit
... | #Elixir | Elixir | defmodule SEDOL do
@sedol_char "0123456789BCDFGHJKLMNPQRSTVWXYZ" |> String.codepoints
@sedolweight [1,3,1,7,3,9]
defp char2value(c) do
unless c in @sedol_char, do: raise ArgumentError, "No vowels"
String.to_integer(c,36)
end
def checksum(sedol) do
if String.length(sedol) != length(@sedolweig... | Give a code snippet in #Elixir
Task
For each number list of 6-digit SEDOLs, calculate and append the checksum digit.
That is, given this input:
710889
B0YBKJ
406566
B0YBLH
228276
B0YBKL
557910
B0YBKR
585284
B0YBKT
B00030
Produce this output:
7108899
B0YBKJ7
4065663
B0YBLH2
2282765
B0YBKL9
5579107
B0YBKR5
585284... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Monads/Maybe_monad | Monads/Maybe monad | Demonstrate in your programming language the following:
Construct a Maybe Monad by writing the 'bind' function and the 'unit' (sometimes known as 'return') function for that Monad (or just use what the language already has implemented)
Make two functions, each which take a number and return a monadic number, e.g. Int ... | #Hoon | Hoon |
:- %say
|= [^ [[txt=(unit ,@tas) ~] ~]]
:- %noun
|^
%+ biff txt
;~ biff
m-parse
m-double
==
++ m-parse
|= a=@tas
^- (unit ,@ud)
(rust (trip a) dem)
::
++ m-double
|= a=@ud
^- (unit ,@ud)
(some (mul a 2))
--
| Give a code snippet in #Hoon
Demonstrate in your programming language the following:
Construct a Maybe Monad by writing the 'bind' function and the 'unit' (sometimes known as 'return') function for that Monad (or just use what the language already has implemented)
Make two functions, each which take a number and retu... | 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... | #BBC_BASIC | BBC BASIC | PRINT "Method 1: Calculate reciprocal of elapsed time:"
FOR trial% = 1 TO 3
start% = TIME
PROCtasktomeasure
finish% = TIME
PRINT "Rate = "; 100 / (finish%-start%) " per second"
NEXT trial%
PRINT '"Method 2: Count completed tasks in one second:"
FOR trial% ... | Give a code snippet in #BBC_BASIC
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_whitespace_from_a_string/Top_and_tail | Strip whitespace from a string/Top and tail | Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whitespace removed
For the purposes of thi... | #Delphi.2FPascal | Delphi/Pascal | program StripWhitespace;
{$APPTYPE CONSOLE}
uses SysUtils;
const
TEST_STRING = ' String with spaces ';
begin
Writeln('"' + TEST_STRING + '"');
Writeln('"' + TrimLeft(TEST_STRING) + '"');
Writeln('"' + TrimRight(TEST_STRING) + '"');
Writeln('"' + Trim(TEST_STRING) + '"');
end. | Give a code snippet in #Delphi.2FPascal
Task
Demonstrate how to strip leading and trailing whitespace from a string.
The solution should demonstrate how to achieve the following three results:
String with leading whitespace removed
String with trailing whitespace removed
String with both leading and trailing whi... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Base64_decode_data | Base64 decode data | See Base64 encode data.
Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file.
When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that showed output with incorrect padding. Obviously... | #Visual_Basic_.NET | Visual Basic .NET | Module Module1
Sub Main()
Dim data = "VG8gZXJyIGlzIGh1bWFuLCBidXQgdG8gcmVhbGx5IGZvdWwgdGhpbmdzIHVwIHlvdSBuZWVkIGEgY29tcHV0ZXIuCiAgICAtLSBQYXVsIFIuIEVocmxpY2g="
Console.WriteLine(data)
Console.WriteLine()
Dim decoded = Text.Encoding.ASCII.GetString(Convert.FromBase64String(data))
... | Give a code snippet in #Visual_Basic_.NET
See Base64 encode data.
Now write a program that takes the output of the Base64 encode data task as input and regenerate the original file.
When working on the VBA implementation I found several 'solutions' on the net, including one from the software maker himself, that show... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Logical_operations | Logical 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 |... | #Standard_ML | Standard ML | fun print_logic (a, b) = (
print ("a and b is " ^ Bool.toString (a andalso b) ^ "\n");
print ("a or b is " ^ Bool.toString (a orelse b) ^ "\n");
print ("not a is " ^ Bool.toString (not a) ^ "\n")
) | Give a code snippet in #Standard_ML
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 Opera... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Enforced_immutability | Enforced immutability | Task
Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
| #Fortran | Fortran | real, parameter :: pi = 3.141593 | Give a code snippet in #Fortran
Task
Demonstrate any means your language has to prevent the modification of values, or to create objects that cannot be modified after they have been created.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #Lasso | Lasso | local(
number = integer_random(10, 1),
status = false,
guess
)
// prompt for a number
stdout('Guess a number between 1 and 10: ')
while(not #status) => {
#guess = null
// the following bits wait until the terminal gives you back a line of input
while(not #guess or #guess -> size == 0) => {
#guess = file_s... | Give a code snippet in #Lasso
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Order_by_pair_comparisons | Order by pair comparisons |
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
... | #11l | 11l | F user_cmp(String a, b)
R Int(input(‘IS #6 <, ==, or > #6 answer -1, 0 or 1:’.format(a, b)))
V items = ‘violet red green indigo blue yellow orange’.split(‘ ’)
V ans = sorted(items, key' cmp_to_key(user_cmp))
print("\n"ans.join(‘ ’)) | Give a code snippet in #11l
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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 ... | #C.23 | C# | static class StdErr
{
static void Main(string[] args)
{
Console.Error.WriteLine("Goodbye, World!");
}
} | Give a code snippet in #C.23
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/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 ... | #Rust | Rust | fn leonardo(mut n0: u32, mut n1: u32, add: u32) -> impl std::iter::Iterator<Item = u32> {
std::iter::from_fn(move || {
let n = n0;
n0 = n1;
n1 += n + add;
Some(n)
})
}
fn main() {
println!("First 25 Leonardo numbers:");
for i in leonardo(1, 1, 1).take(25) {
prin... | Give a code snippet in #Rust
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/Hickerson_series_of_almost_integers | Hickerson series of almost integers | The following function, due to D. Hickerson, is said to generate "Almost integers" by the
"Almost Integer" page of Wolfram MathWorld, (December 31 2013). (See formula numbered 51.)
The function is:
h
(
n
)
=
n
!
2
(
ln
2
)
n
+
1
{\displaystyle h(n)={\operatorname {n} ! \ove... | #C | C | #include <stdio.h>
#include <mpfr.h>
void h(int n)
{
MPFR_DECL_INIT(a, 200);
MPFR_DECL_INIT(b, 200);
mpfr_fac_ui(a, n, MPFR_RNDD); // a = n!
mpfr_set_ui(b, 2, MPFR_RNDD); // b = 2
mpfr_log(b, b, MPFR_RNDD); // b = log(b)
mpfr_pow_ui(b, b, n + 1, MPFR_RNDD); // b = b^(n+1)
mpfr_div(a, a, b, MPFR_RNDD);... | Give a code snippet in #C
The following function, due to D. Hickerson, is said to generate "Almost integers" by the
"Almost Integer" page of Wolfram MathWorld, (December 31 2013). (See formula numbered 51.)
The function is:
h
(
n
)
=
n
!
2
(
ln
2
)
n
+
1
{\displaystyle h(n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gamma_function | Gamma function | Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function.
The Gamma funct... | #OCaml | OCaml | let e = exp 1.
let pi = 4. *. atan 1.
let sqrttwopi = sqrt (2. *. pi)
module Lanczos = struct
(* Lanczos method *)
(* Coefficients used by the GNU Scientific Library *)
let g = 7.
let c = [|0.99999999999980993; 676.5203681218851; -1259.1392167224028;
771.32342877765313; -176.61502916214059; 12.5073432786... | Give a code snippet in #OCaml
Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/lib... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_of_squares | Sum of squares | Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| #VBA | VBA | Public Sub sum_of_squares()
Debug.Print WorksheetFunction.SumSq([{1,2,3,4,5,6,7,8,9,10}])
End Sub | Give a code snippet in #VBA
Task
Write a program to find the sum of squares of a numeric vector.
The program should work on a zero-length vector (with an answer of 0).
Related task
Mean
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Increment_a_numerical_string | Increment a numerical string | Task
Increment a numerical string.
| #i | i | software {
string = "1"
string += 1
print(string)
} | Give a code snippet in #i
Task
Increment a numerical string.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Split_a_character_string_based_on_change_of_character | Split a character string based on change of character |
Task
Split a (character) string into comma (plus a blank) delimited
strings based on a change of character (left to right).
Show the output here (use the 1st example below).
Blanks should be treated as any other character (except
they are problematic to display clearly). The same applies
to commas.
Fo... | #Ring | Ring |
see split("gHHH5YY++///\")
func split(s )
c =left (s, 1)
split = ""
for i = 1 to len(s)
d = substr(s, i, 1)
if d != c
split = split + ", "
c = d
ok
split = split + d
next
return split
| Give a code snippet in #Ring
Task
Split a (character) string into comma (plus a blank) delimited
strings based on a change of character (left to right).
Show the output here (use the 1st example below).
Blanks should be treated as any other character (except
they are problematic to display clearly). The... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perlin_noise | Perlin noise | The Perlin noise is a kind of gradient noise invented by Ken Perlin around the end of the twentieth century and still currently heavily used in computer graphics, most notably to procedurally generate textures or heightmaps.
The Perlin noise is basically a pseudo-random mapping of
R
d
... | #Fortran | Fortran |
PROGRAM PERLIN
IMPLICIT NONE
INTEGER :: i
INTEGER, DIMENSION(0:511) :: p
INTEGER, DIMENSION(0:255), PARAMETER :: permutation = (/151,160,137,91,90,15, &
131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, &
190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33... | Give a code snippet in #Fortran
The Perlin noise is a kind of gradient noise invented by Ken Perlin around the end of the twentieth century and still currently heavily used in computer graphics, most notably to procedurally generate textures or heightmaps.
The Perlin noise is basically a pseudo-rand... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Deconvolution/1D | Deconvolution/1D | The convolution of two functions
F
{\displaystyle {\mathit {F}}}
and
H
{\displaystyle {\mathit {H}}}
of
an integer variable is defined as the function
G
{\displaystyle {\mathit {G}}}
satisfying
G
(
n
)
=
∑
m
=
−
∞
∞
F
(
m
)
H
(
n
−
m
)
{\displaystyle G(n)=\sum _{m=-\inft... | #Python | Python | def ToReducedRowEchelonForm( M ):
if not M: return
lead = 0
rowCount = len(M)
columnCount = len(M[0])
for r in range(rowCount):
if lead >= columnCount:
return
i = r
while M[i][lead] == 0:
i += 1
if i == rowCount:
i = r
... | Give a code snippet in #Python
The convolution of two functions
F
{\displaystyle {\mathit {F}}}
and
H
{\displaystyle {\mathit {H}}}
of
an integer variable is defined as the function
G
{\displaystyle {\mathit {G}}}
satisfying
G
(
n
)
=
∑
m
=
−
∞
∞
F
(
m
)
H
(
n
−
m
)
{\d... | christopher/rosetta-code | |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
Th... | #Swift | Swift | import Foundation
let encoded = "http%3A%2F%2Ffoo%20bar%2F"
if let normal = encoded.stringByReplacingPercentEscapesUsingEncoding(NSUTF8StringEncoding) {
println(normal)
} | Give a code snippet in #Swift
This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #Objective-C | Objective-C | NSFileManager *fm = [NSFileManager defaultManager];
// Pre-OS X 10.5
NSLog(@"%llu", [[fm fileAttributesAtPath:@"input.txt" traverseLink:YES] fileSize]);
// OS X 10.5+
NSLog(@"%llu", [[fm attributesOfItemAtPath:@"input.txt" error:NULL] fileSize]); | Give a code snippet in #Objective-C
Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Abstract_type | Abstract type | Abstract type is a type without instances or without definition.
For example in object-oriented programming using some languages, abstract types can be partial implementations of other types, which are to be derived there-from. An abstract type may provide implementation of some operations and/or components. Abstract ... | #COBOL | COBOL | INTERFACE-ID. Shape.
PROCEDURE DIVISION.
METHOD-ID. perimeter.
DATA DIVISION.
LINKAGE SECTION.
01 ret USAGE FLOAT-LONG.
PROCEDURE DIVISION RETURNING ret.
END METHOD perimeter.
METHOD-ID. shape-area.
DATA DIVISION.
LINKAGE SECTION.
... | Give a code snippet in #COBOL
Abstract type is a type without instances or without definition.
For example in object-oriented programming using some languages, abstract types can be partial implementations of other types, which are to be derived there-from. An abstract type may provide implementation of some operatio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_input/output | File input/output | File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a file into a variable
how to write ... | #AutoHotkey | AutoHotkey | Loop, Read, input.txt, output.txt
FileAppend, %A_LoopReadLine%`n | Give a code snippet in #AutoHotkey
File input/output is part of Short Circuit's Console Program Basics selection.
Task
Create a file called "output.txt", and place in it the contents of the file "input.txt", via an intermediate variable.
In other words, your program will demonstrate:
how to read from a f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knuth%27s_power_tree | Knuth's power tree | (Knuth's power tree is used for computing xn efficiently.)
Task
Compute and show the list of Knuth's power tree integers necessary for the computation of:
xn for any real x and any non-negative integer n.
Then, using those integers, calculate and show the exact values of (at least) the integer po... | #Sidef | Sidef | var lvl = [[1]]
var p = Hash(1 => 0)
func path(n) is cached {
n || return []
while (n !~ p) {
var q = []
for x in lvl[0] {
for y in path(x) {
break if (x+y ~~ p)
y = x+y
p{y} = x
q << y
}
}
... | Give a code snippet in #Sidef
(Knuth's power tree is used for computing xn efficiently.)
Task
Compute and show the list of Knuth's power tree integers necessary for the computation of:
xn for any real x and any non-negative integer n.
Then, using those integers, calculate and show the exact valu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Palindrome_detection | Palindrome detection | A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possibly as a wrapper to the first) which ... | #AutoHotkey | AutoHotkey | IsPalindrome(Str){
Loop, Parse, Str
ReversedStr := A_LoopField . ReversedStr
return, (ReversedStr == Str)?"Exact":(RegExReplace(ReversedStr,"\W")=RegExReplace(Str,"\W"))?"Inexact":"False"
} | Give a code snippet in #AutoHotkey
A palindrome is a phrase which reads the same backward and forward.
Task[edit]
Write a function or program that checks whether a given sequence of characters (or, if you prefer, bytes)
is a palindrome.
For extra credit:
Support Unicode characters.
Write a second function (possib... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #XPL0 | XPL0 | include c:\cxpl\codes;
int B, C, F, M, S;
for B:= 1 to 4 do \Baker does not live on top (5th) floor
for C:= 2 to 5 do \Cooper does not live on bottom floor
if C#B then \Cooper & Baker live on different floors
for F:= 2 to 4 do ... | Give a code snippet in #XPL0
Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are al... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file | Create a file | In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| #Groovy | Groovy | new File("output.txt").createNewFile()
new File(File.separator + "output.txt").createNewFile()
new File("docs").mkdir()
new File(File.separator + "docs").mkdir() | Give a code snippet in #Groovy
In this task, the job is to create a new empty file called "output.txt" of size 0 bytes
and an empty directory called "docs". This should be done twice: once "here", i.e. in the current working directory and once in the filesystem root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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 |... | #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program comparNumber.s */
/* Constantes */
.equ BUFFERSIZE, 100
.equ STDIN, 0 @ Linux input console
.equ STDOUT, 1 @ Linux output console
.equ EXIT, 1 @ Linux syscall
.equ READ, 3 @ Linux syscall
.equ WRITE, 4 @ Linux syscall
/* Initialized dat... | Give a code snippet in #ARM_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/First_perfect_square_in_base_n_with_n_unique_digits | First perfect square in base n with n unique digits | Find the first perfect square in a given base N that has at least N digits and
exactly N significant unique digits when expressed in base N.
E.G. In base 10, the first perfect square with at least 10 unique digits is 1026753849 (32043²).
You may use analytical methods to reduce the search space, but the code must do ... | #Raku | Raku | #`[
Only search square numbers that have at least N digits;
smaller could not possibly match.
Only bother to use analytics for large N. Finesse takes longer than brute force for small N.
]
unit sub MAIN ($timer = False);
sub first-square (Int $n) {
my @start = flat '1', '0', (2 ..^ $n)».base: $n;
if... | Give a code snippet in #Raku
Find the first perfect square in a given base N that has at least N digits and
exactly N significant unique digits when expressed in base N.
E.G. In base 10, the first perfect square with at least 10 unique digits is 1026753849 (32043²).
You may use analytical methods to reduce the searc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
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0
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0
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... | #LFE | LFE |
(defun identity
((`(,m ,n))
(identity m n))
((m)
(identity m m)))
(defun identity (m n)
(lists:duplicate m (lists:duplicate n 1)))
| Give a code snippet in #LFE
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factors_of_a_Mersenne_number | Factors of a Mersenne number | A Mersenne number is a number in the form of 2P-1.
If P is prime, the Mersenne number may be a Mersenne prime
(if P is not prime, the Mersenne number is also not prime).
In the search for Mersenne prime numbers it is advantageous to eliminate exponents by finding a small factor before starting a, potentially lengthy,... | #Ada | Ada | with Ada.Text_IO;
-- reuse Is_Prime from [[Primality by Trial Division]]
with Is_Prime;
procedure Mersenne is
function Is_Set (Number : Natural; Bit : Positive) return Boolean is
begin
return Number / 2 ** (Bit - 1) mod 2 = 1;
end Is_Set;
function Get_Max_Bit (Number : Natural) return Natural is
... | Give a code snippet in #Ada
A Mersenne number is a number in the form of 2P-1.
If P is prime, the Mersenne number may be a Mersenne prime
(if P is not prime, the Mersenne number is also not prime).
In the search for Mersenne prime numbers it is advantageous to eliminate exponents by finding a small factor before sta... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #Picat | Picat | go =>
L1 = {1,2,3,4,5}, % define an array with {}
L2 = {6,7,8,9},
% The built-in array/list concatenation
println(L1 ++ L2),
% Using the built-in append/3 works only on lists
% so the arrays must be converted to lists.
append(L1.to_list,L2.to_list,L3),
println(L3.to_array),
nl. | Give a code snippet in #Picat
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_and_product_of_an_array | Sum and product of an array | Task
Compute the sum and product of an array of integers.
| #Raven | Raven | 0 [ 1 2 3 ] each +
1 [ 1 2 3 ] each * | Give a code snippet in #Raven
Task
Compute the sum and product of an array of integers.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Identity_matrix | Identity matrix | Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
0
0
0
1
⋯
0
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⋮
⋮
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... | #MATLAB_.2F_Octave | MATLAB / Octave | I = eye(10) | Give a code snippet in #MATLAB_.2F_Octave
Task
Build an identity matrix of a size known at run-time.
An identity matrix is a square matrix of size n × n,
where the diagonal elements are all 1s (ones),
and all the other elements are all 0s (zeroes).
I
n
=
[
1
0
0
⋯
0
0
1
0
⋯
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Priority_queue | Priority queue | A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priority order instead of in insert... | #zkl | zkl | class PQ{
fcn init(numLevels=10){ // 0..numLevels, bigger # == lower priorty
var [const] queue=(1).pump(numLevels+1,List.createLong(numLevels).write,L().copy);
}
fcn add(item,priorty){ queue[priorty].append(item); }
fcn peek{ if(q:=queue.filter1()) return(q[-1]); Void }// -->Void if empty
fcn po... | Give a code snippet in #zkl
A priority queue is somewhat similar to a queue, with an important distinction: each item is added to a priority queue with a priority level, and will be later removed from the queue with the highest priority element first. That is, the items are (conceptually) stored in the queue in priori... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_triangle/Graphical | Sierpinski triangle/Graphical | Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| #Lua | Lua | -- The argument 'tri' is a list of co-ords: {x1, y1, x2, y2, x3, y3}
function sierpinski (tri, order)
local new, p, t = {}
if order > 0 then
for i = 1, #tri do
p = i + 2
if p > #tri then p = p - #tri end
new[i] = (tri[i] + tri[p]) / 2
end
sierpinski({t... | Give a code snippet in #Lua
Produce a graphical representation of a Sierpinski triangle of order N in any orientation.
An example of Sierpinski's triangle (order = 8) looks like this:
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Simple_database | Simple database | Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be a collection (CDs, coins, base... | #Wren | Wren | /* simdb.wren */
import "os" for Process
import "/ioutil" for File, FileFlags, FileUtil
import "/trait" for Comparable, Reversed
import "/date" for Date
import "/sort" for Sort
import "/str" for Str
var fileName = "simdb.csv"
Date.default = Date.isoDate
class Item is Comparable {
construct new(name, date, c... | Give a code snippet in #Wren
Task
Write a simple tool to track a small set of data.
The tool should have a command-line interface to enter at least two different values.
The entered data should be stored in a structured format and saved to disk.
It does not matter what kind of data is being tracked. It could be ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
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 l... | #hexiscript | hexiscript | while true; println "SPAM"; endwhile | Give a code snippet in #hexiscript
Task
Print out SPAM followed by a newline in an infinite loop.
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
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Formatted_numeric_output | Formatted numeric output | Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| #Emacs_Lisp | Emacs Lisp | (format "%09.3f" 7.125) ;=> "00007.125" | Give a code snippet in #Emacs_Lisp
Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stern-Brocot_sequence | Stern-Brocot sequence | For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member of the sequence and its prece... | #CLU | CLU | stern = proc (n: int) returns (array[int])
s: array[int] := array[int]$fill(1, n, 1)
for i: int in int$from_to(2, n/2) do
s[i*2-1] := s[i] + s[i-1]
s[i*2] := s[i]
end
return (s)
end stern
gcd = proc (a,b: int) returns (int)
while b ~= 0 do
a, b := b, a//b
end
return... | Give a code snippet in #CLU
For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/2048 | 2048 | Task
Implement a 2D sliding block puzzle game where blocks with numbers are combined to add their values.
Rules of the game
The rules are that on each turn the player must choose a direction (up, down, left or right).
All tiles move as far as possible in that direction, some move more than others.
Two ... | #Nim | Nim | import random, strutils, terminal
const
BoardLength = 4
BoardSize = BoardLength * BoardLength
Target = 2048
type
Operation = enum
opInvalid
opUp
opDown
opLeft
opRight
opQuit
opRestart
Board = object
len: Natural
largestNumber: Natural
score: Natural
rows: arra... | Give a code snippet in #Nim
Task
Implement a 2D sliding block puzzle game where blocks with numbers are combined to add their values.
Rules of the game
The rules are that on each turn the player must choose a direction (up, down, left or right).
All tiles move as far as possible in that direction, some mo... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #SSEM | SSEM | 00000000000000000000000000000000 0. 0 to CI jump to store(0) + 1
00000000000000000000000000000000 1. 0 to CI jump to store(0) + 1 | Give a code snippet in #SSEM
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Cumulative_standard_deviation | Cumulative standard deviation | Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the function in the implementation langu... | #Scheme | Scheme |
(define (standart-deviation-generator)
(let ((nums '()))
(lambda (x)
(set! nums (cons x nums))
(let* ((mean (/ (apply + nums) (length nums)))
(mean-sqr (lambda (y) (expt (- y mean) 2)))
(variance (/ (apply + (map mean-sqr nums)) (length nums))))
(sqrt variance)))))
(let loop ((f (... | Give a code snippet in #Scheme
Task[edit]
Write a stateful function, class, generator or co-routine that takes a series of floating point numbers, one at a time, and returns the running standard deviation of the series.
The task implementation should use the most natural programming style of those listed for the func... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Return_multiple_values | Return multiple values | Task
Show how to return more than one value from a function.
| #Visual_FoxPro | Visual FoxPro |
*!* Return multiple values from a function
*!* The simplest way is to pass the parameters by reference
*!* either by SET UDFPARMS TO REFERENCE, or prefix the variables with @.
LOCAL a, b
a = 5
b = 6
? "Sum =", AddUp(@a, @b) && Displays 11
? "a =", a, "b =", b && Displays 4, 5
? "Sum =", AddUp(@a, @b) && ... | Give a code snippet in #Visual_FoxPro
Task
Show how to return more than one value from a function.
| 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... | #EasyLang | EasyLang | for i = 10 downto 0
print i
. | Give a code snippet in #EasyLang
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/Inc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_missing_permutation | Find the missing permutation | ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
CDBA
... | #REXX | REXX | /*REXX pgm finds one or more missing permutations from an internal list & displays them.*/
list= 'ABCD CABD ACDB DACB BCDA ACBD ADCB CDAB DABC BCAD CADB CDBA CBAD ABDC ADBC BDCA',
"DCBA BACD BADC BDAC CBDA DBCA DCAB" /*list that is missing one permutation.*/
@.= ... | Give a code snippet in #REXX
ABCD
CABD
ACDB
DACB
BCDA
ACBD
ADCB
CDAB
DABC
BCAD
CADB
... | 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.
| #6502_Assembly | 6502 Assembly | ;DEFINING INTERRUPT VECTORS ON THE NES
org $FFFA
dw #### ;address of your NMI handler goes here (you can use labels for each of these for your convenience)
dw #### ;address of your Reset handler goes here
dw #### ;address of your IRQ handler goes here. | Give a code snippet in #6502_Assembly
Special variables have a predefined meaning within a computer programming language.
Task
List the special variables used within the language.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Video_display_modes | Video display modes | The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| #XPL0 | XPL0 | code SetVid=45;
SetVid(Mode) | Give a code snippet in #XPL0
The task is to demonstrate how to switch video display modes within the language. A brief description of the supported video modes would be useful.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #Yabasic | Yabasic | l$ = "1,1234,62,234,12,34,6"
dim n$(1)
n = token(l$, n$(), ", ")
for i = 1 to n
t$ = n$(i)
if t$ > m$ then m$ = t$ end if // or: if t$ > m$ m$ = t$
if val(t$) > m then m = val(t$) end if // or: if val(t$) > m m = val(t$)
next
print "Alphabetic order: ", m$, ", numeric order: ", m | Give a code snippet in #Yabasic
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/Zeckendorf_arithmetic | Zeckendorf arithmetic | This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation.
The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation functions.
Addition
Like bin... | #D | D | import std.stdio;
int inv(int a) {
return a ^ -1;
}
class Zeckendorf {
private int dVal;
private int dLen;
private void a(int n) {
auto i = n;
while (true) {
if (dLen < i) dLen = i;
auto j = (dVal >> (i * 2)) & 3;
switch(j) {
case... | Give a code snippet in #D
This task is a total immersion zeckendorf task; using decimal numbers will attract serious disapprobation.
The task is to implement addition, subtraction, multiplication, and division using Zeckendorf number representation. Optionally provide decrement, increment and comparitive operation fu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Floyd-Warshall_algorithm | Floyd-Warshall algorithm | The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has already been checked for loops, parallel ... | #Modula-2 | Modula-2 | MODULE FloydWarshall;
FROM FormatString IMPORT FormatString;
FROM SpecialReals IMPORT Infinity;
FROM Terminal IMPORT ReadChar,WriteString,WriteLn;
CONST NUM_VERTICIES = 4;
TYPE
IntArray = ARRAY[0..NUM_VERTICIES-1],[0..NUM_VERTICIES-1] OF INTEGER;
RealArray = ARRAY[0..NUM_VERTICIES-1],[0..NUM_VERTICIES-1] OF R... | Give a code snippet in #Modula-2
The Floyd–Warshall algorithm is an algorithm for finding shortest paths in a weighted graph with positive or negative edge weights.
Task
Find the lengths of the shortest paths between all pairs of vertices of the given directed graph. Your code may assume that the input has already... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence:_smallest_number_greater_than_previous_term_with_exactly_n_divisors | Sequence: smallest number greater than previous term with exactly n divisors | Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A069654
Related tasks
Sequence: smallest number with exactly n divisors
Sequence: nth ... | #Phix | Phix | with javascript_semantics
constant limit = 15
sequence res = repeat(0,limit)
integer next = 1
atom n = 1
while next<=limit do
integer k = length(factors(n,1))
if k=next then
res[k] = n
next += 1
if next>4 and is_prime(next) then
n := power(2,next-1)-1 -- (-1 for +=1 next)
... | Give a code snippet in #Phix
Calculate the sequence where each term an is the smallest natural number greater than the previous term, that has exactly n divisors.
Task
Show here, on this page, at least the first 15 terms of the sequence.
See also
OEIS:A069654
Related tasks
Sequence: smallest number with exac... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Narcissistic_decimal_number | Narcissistic decimal number | A Narcissistic decimal number is a non-negative integer,
n
{\displaystyle n}
, that is equal to the sum of the
m
{\displaystyle m}
-th powers of each of the digits in the decimal representation of
n
{\displaystyle n}
, where
m
{\displaystyle m}
is the number of digits in... | #C.23 | C# |
using System;
namespace Narcissistic
{
class Narcissistic
{
public bool isNarcissistic(int z)
{
if (z < 0) return false;
string n = z.ToString();
int t = 0, l = n.Length;
foreach (char c in n)
t += Convert.ToInt32(Math.Pow(Conve... | Give a code snippet in #C.23
A Narcissistic decimal number is a non-negative integer,
n
{\displaystyle n}
, that is equal to the sum of the
m
{\displaystyle m}
-th powers of each of the digits in the decimal representation of
n
{\displaystyle n}
, where
m
{\displaystyle m}
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers/Pascal%27s_triangle | Catalan numbers/Pascal's triangle | Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that generates Catalan Numbers using onl... | #Ring | Ring |
n=15
cat = list(n+2)
cat[1]=1
for i=1 to n
for j=i+1 to 2 step -1
cat[j]=cat[j]+cat[j-1]
next
cat[i+1]=cat[i]
for j=i+2 to 2 step -1
cat[j]=cat[j]+cat[j-1]
next
see "" + (cat[i+1]-cat[i]) + " "
next
| Give a code snippet in #Ring
Task
Print out the first 15 Catalan numbers by extracting them from Pascal's triangle.
See
Catalan Numbers and the Pascal Triangle. This method enables calculation of Catalan Numbers using only addition and subtraction.
Catalan's Triangle for a Number Triangle that gener... | 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... | #11l | 11l | F leaf_plot(&x)
x.sort()
V i = x[0] I/ 10 - 1
L(j) 0 .< x.len
V d = x[j] I/ 10
L d > i
i++
print(‘#.#3 |’.format((j != 0) * "\n", i), end' ‘’)
print(‘ ’(x[j] % 10), end' ‘’)
print()
V data = [
12, 127, 28, 42, 39, 113, 42, 18, 44, 118, 44, 37, 113, 124,
... | Give a code snippet in #11l
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 12... | christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #Icon_and_Unicon | Icon and Unicon | procedure main()
WOpen("size=800,800") | stop("Unable to open window")
WWrite("Enter a string:")
s := WRead()
WWrite("You entered ",image(s))
WWrite("Enter the integer 75000:")
i := WRead()
if i := integer(i) then
WWrite("You entered: ",i)
else
WWrite(image(i)," isn't an integer")
WDone()
end
link graphics | Give a code snippet in #Icon_and_Unicon
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm | Bitmap/Midpoint circle algorithm | Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| #Julia | Julia | function drawcircle!(img::Matrix{T}, col::T, x0::Int, y0::Int, radius::Int) where T
x = radius - 1
y = 0
δx = δy = 1
er = δx - (radius << 1)
s = x + y
while x ≥ y
for opx in (+, -), opy in (+, -), el in (x, y)
@inbounds img[opx(x0, el) + 1, opy(y0, s - el) + 1] = col
... | Give a code snippet in #Julia
Task
Using the data storage type defined on this page for raster images,
write an implementation of the midpoint circle algorithm (also known as Bresenham's circle algorithm).
(definition on Wikipedia).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Population_count | Population count | Population count
You are encouraged to solve this task according to the task description, using any language you may know.
The population count is the number of 1s (ones) in the binary representation of a non-negative integer.
Population count is also known as:
pop count
popcount
sideways sum
... | #CLU | CLU | pop_count = proc (n: int) returns (int)
p: int := 0
while n>0 do
p := p + n//2
n := n/2
end
return(p)
end pop_count
evil = proc (n: int) returns (bool)
return(pop_count(n)//2 = 0)
end evil
odious = proc (n: int) returns (bool)
return(~evil(n))
end odious
first = iter (n: in... | Give a code snippet in #CLU
Population count
You are encouraged to solve this task according to the task description, using any language you may know.
The population count is the number of 1s (ones) in the binary representation of a non-negative integer.
Population count is also known as:
pop count
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Humble_numbers | Humble numbers | Humble numbers are positive integers which have no prime factors > 7.
Humble numbers are also called 7-smooth numbers, and sometimes called highly composite,
although this conflicts with another meaning of highly composite numbers.
Another way to express the above is:
humble = 2i × 3j × 5k... | #JavaScript | JavaScript | (() => {
'use strict';
// ------------------ HUMBLE NUMBERS -------------------
// humbles :: () -> [Int]
function* humbles() {
// A non-finite stream of Humble numbers.
// OEIS A002473
const hs = new Set([1]);
while (true) {
let nxt = Math.min(...hs)
... | Give a code snippet in #JavaScript
Humble numbers are positive integers which have no prime factors > 7.
Humble numbers are also called 7-smooth numbers, and sometimes called highly composite,
although this conflicts with another meaning of highly composite numbers.
Another way to express the ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Continued_fraction/Arithmetic/Construct_from_rational_number | Continued fraction/Arithmetic/Construct from rational number | Continued fraction arithmetic
The purpose of this task is to write a function
r
2
c
f
(
i
n
t
{\displaystyle {\mathit {r2cf}}(\mathrm {int} }
N
1
,
i
n
t
{\displaystyle N_{1},\mathrm {int} }
N
2
)
{\displaystyle N_{2})}
, or
r
2
c
f
(
F
r
a
c
t
i
o
n
{\displaystyle {\m... | #Kotlin | Kotlin | // version 1.1.2
// compile with -Xcoroutines=enable flag from command line
import kotlin.coroutines.experimental.buildSequence
fun r2cf(frac: Pair<Int, Int>) =
buildSequence {
var num = frac.first
var den = frac.second
while (Math.abs(den) != 0) {
val div = num / den
... | Give a code snippet in #Kotlin
Continued fraction arithmetic
The purpose of this task is to write a function
r
2
c
f
(
i
n
t
{\displaystyle {\mathit {r2cf}}(\mathrm {int} }
N
1
,
i
n
t
{\displaystyle N_{1},\mathrm {int} }
N
2
)
{\displaystyle N_{2})}
, or
r
2
c
f
(
F
r
a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Euler%27s_sum_of_powers_conjecture | Euler's sum of powers conjecture | There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power,
except for the trivial case... | #XPL0 | XPL0 | func real Pow5(N);
int N;
real X, P;
[X:= float(N);
P:= X*X;
P:= P*P;
return P*X;
];
int X0, X1, X2, X3, Y;
real SP;
[for X0:= 1 to 250 do
for X1:= 1 to X0-1 do
for X2:= 1 to X1-1 do
for X3:= 1 to X2-1 do
[SP:= Pow5(X0) + Pow5(X1) + Pow5(X2) + Pow5(X3);
for Y:= X0+1 to 250 do
i... | Give a code snippet in #XPL0
There is a conjecture in mathematics that held for over two hundred years before it was disproved by the finding of a counterexample in 1966 by Lander and Parkin.
Euler's (disproved) sum of powers conjecture
At least k positive kth powers are required to sum to a kth power, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Creation | Associative array/Creation | Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element ins... | #Ol | Ol |
;;; empty associative array
#empty
; or short form
#e
;;; creating the new empty associative array
(define empty-map #empty)
;;; creating associative array with values
(define my-map (pairs->ff '(
(1 . 100)
(2 . 200)
(7 . 777))))
;;; or in short form (available from Ol version 2.1)
(define my-map {
1 ... | Give a code snippet in #Ol
Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Ele... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #zkl | zkl | doors:=List.createLong(100,False); // list of 100 Falses
foreach n,m in (100,[n..99,n+1]){ doors[m]=(not doors[m]); } //foreach{ foreach{} }
doors.filterNs().apply('+(1)).println(); | Give a code snippet in #zkl
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...)... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Action.21 | Action! | TYPE Result=[BYTE success,sum,highCount]
BYTE FUNC GenerateAttrib()
BYTE i,v,min,sum
min=255 sum=0
FOR i=0 TO 3
DO
v=Rand(6)+1
IF v<min THEN
min=v
FI
sum==+v
OD
RETURN (sum-min)
PROC Generate(BYTE ARRAY a BYTE len Result POINTER res)
BYTE i,v,count
res.highCount=0 res.sum=0
F... | Give a code snippet in #Action.21
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, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gray_code | Gray code | Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are many possible Gray codes. The follow... | #Haskell | Haskell | import Data.Bits
import Data.Char
import Numeric
import Control.Monad
import Text.Printf
grayToBin :: (Integral t, Bits t) => t -> t
grayToBin 0 = 0
grayToBin g = g `xor` (grayToBin $ g `shiftR` 1)
binToGray :: (Integral t, Bits t) => t -> t
binToGray b = b `xor` (b `shiftR` 1)
showBinary :: (Integral t, Show t) ... | Give a code snippet in #Haskell
Gray code
Karnaugh maps
Create functions to encode a number to and decode a number from Gray code.
Display the normal binary representations, Gray code representations, and decoded Gray code values for all 5-bit binary numbers (0-31 inclusive, leading 0's not necessary).
There are man... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_the_intersection_of_a_line_with_a_plane | Find the intersection of a line with a plane | Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of (0, 0, 1) and which passes ... | #Rust | Rust | use std::ops::{Add, Div, Mul, Sub};
#[derive(Copy, Clone, Debug, PartialEq)]
struct V3<T> {
x: T,
y: T,
z: T,
}
impl<T> V3<T> {
fn new(x: T, y: T, z: T) -> Self {
V3 { x, y, z }
}
}
fn zip_with<F, T, U>(f: F, a: V3<T>, b: V3<T>) -> V3<U>
where
F: Fn(T, T) -> U,
{
V3 {
x... | Give a code snippet in #Rust
Finding the intersection of an infinite ray with a plane in 3D is an important topic in collision detection.
Task
Find the point of intersection for the infinite ray with direction (0, -1, -1) passing through position (0, 0, 10) with the infinite plane with a normal vector of ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Wieferich_primes | Wieferich primes |
This page uses content from Wikipedia. The original article was at Wieferich prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In number theory, a Wieferich prime is a prime number p such th... | #Ruby | Ruby | require "prime"
puts Prime.each(5000).select{|p| 2.pow(p-1 ,p*p) == 1 }
| Give a code snippet in #Ruby
This page uses content from Wikipedia. The original article was at Wieferich prime. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
In number theory, a Wieferich prime... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Run-length_encoding | Run-length encoding | Run-length encoding
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a function to reverse the compression... | #OCaml | OCaml | let encode str =
let len = String.length str in
let rec aux i acc =
if i >= len then List.rev acc
else
let c1 = str.[i] in
let rec aux2 j =
if j >= len then (c1, j-i)
else
let c2 = str.[j] in
if c1 = c2
then aux2 (j+1)
else (c1, j-i)
... | Give a code snippet in #OCaml
Run-length encoding
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a func... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Diversity_prediction_theorem | Diversity prediction theorem | The wisdom of the crowd is the collective opinion of a group of individuals rather than that of a single expert.
Wisdom-of-the-crowds research routinely attributes the superiority of crowd averages over individual judgments to the elimination of individual noise, an explanation that assumes independence of the i... | #Jsish | Jsish | /* Diverisity Prediction Theorem, in Jsish */
"use strict";
function sum(arr:array):number {
return arr.reduce(function(acc, cur, idx, arr) { return acc + cur; });
}
function square(x:number):number {
return x * x;
}
function mean(arr:array):number {
return sum(arr) / arr.length;
}
function averageS... | Give a code snippet in #Jsish
The wisdom of the crowd is the collective opinion of a group of individuals rather than that of a single expert.
Wisdom-of-the-crowds research routinely attributes the superiority of crowd averages over individual judgments to the elimination of individual noise, an explanation tha... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Terminal_control/Cursor_movement | Terminal control/Cursor movement | Task
Demonstrate how to achieve movement of the terminal cursor:
how to move the cursor one position to the left
how to move the cursor one position to the right
how to move the cursor up one line (without affecting its horizontal position)
how to move the cursor down one line (without affecting its horizontal po... | #Python | Python | import curses
scr = curses.initscr()
# Demonstrate how to move the cursor one position to the left
def move_left():
y,x = curses.getyx()
curses.move(y,x-1)
# Demonstrate how to move the cursor one position to the right
def move_right():
y,x = curses.getyx()
curses.move(y,x+1)
# Demonstrate how to mo... | Give a code snippet in #Python
Task
Demonstrate how to achieve movement of the terminal cursor:
how to move the cursor one position to the left
how to move the cursor one position to the right
how to move the cursor up one line (without affecting its horizontal position)
how to move the cursor down one line (wit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stirling_numbers_of_the_second_kind | Stirling numbers of the second kind | Stirling numbers of the second kind, or Stirling partition numbers, are the
number of ways to partition a set of n objects into k non-empty subsets. They are
closely related to Bell numbers, and may be derived from them.
Stirling numbers of the second kind obey the recurrence relation:
S2(n, 0) and S2(0, k) = 0 ... | #Nim | Nim | import sequtils, strutils
proc s2(n, k: Natural): Natural =
if n == k: return 1
if n == 0 or k == 0: return 0
k * s2(n - 1, k) + s2(n - 1, k - 1)
echo " k ", toSeq(0..12).mapIt(($it).align(2)).join(" ")
echo " n"
for n in 0..12:
stdout.write ($n).align(2)
for k in 0..n:
stdout.write ($s2(n, ... | Give a code snippet in #Nim
Stirling numbers of the second kind, or Stirling partition numbers, are the
number of ways to partition a set of n objects into k non-empty subsets. They are
closely related to Bell numbers, and may be derived from them.
Stirling numbers of the second kind obey the recurrence relation:
... | christopher/rosetta-code |
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