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/Detect_division_by_zero | Detect division by zero | Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| #AutoHotkey | AutoHotkey | ZeroDiv(num1, num2) {
If ((num1/num2) != "")
MsgBox % num1/num2
Else
MsgBox, 48, Warning, The result is not valid (Divide By Zero).
}
ZeroDiv(0, 3) ; is ok
ZeroDiv(3, 0) ; divize by zero alert | Give a code snippet in #AutoHotkey
Task
Write a function to detect a divide by zero error without checking if the denominator is zero.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic-geometric_mean/Calculate_Pi | Arithmetic-geometric mean/Calculate Pi | Almkvist Berndt 1988 begins with an investigation of why the agm is such an efficient algorithm, and proves that it converges quadratically. This is an efficient method to calculate
π
{\displaystyle \pi }
.
With the same notations used in Arithmetic-geometric mean, we can summarize the paper by writing:
π
... | #Maple | Maple | agm:=proc(n)
local a:=1,g:=evalf(sqrt(1/2)),s:=0,p:=4,i;
for i to n do
a,g:=(a+g)/2,sqrt(a*g);
s+=p*(a*a-g*g);
p+=p
od;
4*a*a/(1-s)
end:
Digits:=100000:
d:=agm(16)-evalf(Pi):
evalf[10](d);
# 4.280696926e-89415 | Give a code snippet in #Maple
Almkvist Berndt 1988 begins with an investigation of why the agm is such an efficient algorithm, and proves that it converges quadratically. This is an efficient method to calculate
π
{\displaystyle \pi }
.
With the same notations used in Arithmetic-geometric mean, we can summariz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_length | String length | Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme containing combining characters.
F... | #Erlang | Erlang | 9> U = "𝔘𝔫𝔦𝔠𝔬𝔡𝔢".
[120088,120107,120102,120096,120108,120097,120098]
10> erlang:length(U).
7
| Give a code snippet in #Erlang
Task
Find the character and byte length of a string.
This means encodings like UTF-8 need to be handled properly, as there is not necessarily a one-to-one relationship between bytes and characters.
By character, we mean an individual Unicode code point, not a user-visible grapheme con... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hamming_numbers | Hamming numbers | Hamming numbers are numbers of the form
H = 2i × 3j × 5k
where
i, j, k ≥ 0
Hamming numbers are also known as ugly numbers and also 5-smooth numbers (numbers whose prime divisors are less or equal to 5).
Task
Generate the sequence of Hamming numbers, in increasing order. In ... | #Seed7 | Seed7 | $ include "seed7_05.s7i";
include "bigint.s7i";
const func bigInteger: min (in bigInteger: a, in bigInteger: b, in bigInteger: c) is func
result
var bigInteger: min is 0_;
begin
if a < b then
min := a;
else
min := b;
end if;
if c < min then
min := c;
end if;
end func;... | Give a code snippet in #Seed7
Hamming numbers are numbers of the form
H = 2i × 3j × 5k
where
i, j, k ≥ 0
Hamming numbers are also known as ugly numbers and also 5-smooth numbers (numbers whose prime divisors are less or equal to 5).
Task
Generate the sequence of Hamming numb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/HTTPS/Authenticated | HTTPS/Authenticated | The goal of this task is to demonstrate HTTPS requests with authentication.
Implementations of this task should not use client certificates for this: that is the subject of another task.
| #Python | Python | #!/usr/bin/python
# -*- coding: utf-8 -*-
from mechanize import Browser
USER_AGENT = "Mozilla/5.0 (X11; U; Linux i686; tr-TR; rv:1.8.1.9) Gecko/20071102 Pardus/2007 Firefox/2.0.0.9"
br = Browser()
br.addheaders = [("User-agent", USER_AGENT)]
# remove comment if you get debug output
# br.set_debug_redirects(True... | Give a code snippet in #Python
The goal of this task is to demonstrate HTTPS requests with authentication.
Implementations of this task should not use client certificates for this: that is the subject of another task.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/S-expressions | S-expressions | S-Expressions are one convenient way to parse and store data.
Task
Write a simple reader and writer for S-Expressions that handles quoted and unquoted strings, integers and floats.
The reader should read a single but nested S-Expression from a string and store it in a suitable datastructure (list, array, etc).
... | #C | C | #include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
enum { S_NONE, S_LIST, S_STRING, S_SYMBOL };
typedef struct {
int type;
size_t len;
void *buf;
} s_expr, *expr;
void whine(const char *s)
{
fprintf(stderr, "parse error before ==>%.10s\n", s);
}
expr parse_string(const char *s, ch... | Give a code snippet in #C
S-Expressions are one convenient way to parse and store data.
Task
Write a simple reader and writer for S-Expressions that handles quoted and unquoted strings, integers and floats.
The reader should read a single but nested S-Expression from a string and store it in a suitable datastru... | christopher/rosetta-code | |
http://rosettacode.org/wiki/15_puzzle_game | 15 puzzle game |
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| #R | R |
puz15<-function(scramble.length=100){
m=matrix(c(1:15,0),byrow=T,ncol=4)
scramble=sample(c("w","a","s","d"),scramble.length,replace=T)
for(i in 1:scramble.length){
m=move(m,scramble[i])
}
win=F
turn=0
while(!win){
print.puz(m)
newmove=getmove()
if(newmove=="w"|newmove=="a"|newmove=="s"|n... | Give a code snippet in #R
Task
Implement the Fifteen Puzzle Game.
The 15-puzzle is also known as:
Fifteen Puzzle
Gem Puzzle
Boss Puzzle
Game of Fifteen
Mystic Square
14-15 Puzzle
and some others.
Related Tasks
15 Puzzle Solver
16 Puzzle Game
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fractal_tree | Fractal tree | Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| #Kotlin | Kotlin | // version 1.1.2
import java.awt.Color
import java.awt.Graphics
import javax.swing.JFrame
class FractalTree : JFrame("Fractal Tree") {
init {
background = Color.black
setBounds(100, 100, 800, 600)
isResizable = false
defaultCloseOperation = EXIT_ON_CLOSE
}
private fun d... | Give a code snippet in #Kotlin
Generate and draw a fractal tree.
Draw the trunk
At the end of the trunk, split by some angle and draw two branches
Repeat at the end of each branch until a sufficient level of branching is reached
Related tasks
Pythagoras Tree
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Zebra_puzzle | Zebra puzzle | Zebra puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
The Zebra puzzle, a.k.a. Einstein's Riddle,
is a logic puzzle which is to be solved programmatically.
It has several variants, one of them this:
There are five houses.
The English man lives ... | #GAP | GAP | leftOf :=function(setA, vA, setB, vB)
local i;
for i in [1..4] do
if ( setA[i] = vA) and (setB[i+1] = vB) then return true ;fi;
od;
return false;
end;
nextTo :=function(setA, vA, setB, vB)
local i;
for i in [1..4] do
if ( setA[i] = vA) and (setB[i+1] = vB) then return true ;fi;
if ( setB[i] = vB) and (... | Give a code snippet in #GAP
Zebra puzzle
You are encouraged to solve this task according to the task description, using any language you may know.
The Zebra puzzle, a.k.a. Einstein's Riddle,
is a logic puzzle which is to be solved programmatically.
It has several variants, one of them this:
There are five hous... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Median | Averages/Median | Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle values.
There are several approaches ... | #Lua | Lua | function median (numlist)
if type(numlist) ~= 'table' then return numlist end
table.sort(numlist)
if #numlist %2 == 0 then return (numlist[#numlist/2] + numlist[#numlist/2+1]) / 2 end
return numlist[math.ceil(#numlist/2)]
end
print(median({4.1, 5.6, 7.2, 1.7, 9.3, 4.4, 3.2}))
print(median({4.1, 7.2, 1... | Give a code snippet in #Lua
Task[edit]
Write a program to find the median value of a vector of floating-point numbers.
The program need not handle the case where the vector is empty, but must handle the case where there are an even number of elements. In that case, return the average of the two middle values.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #ALGOL_68 | ALGOL 68 | STRINGa="STRINGa=,q=REPR34;print(a[:8]+q+a+q+a[9:])",q=REPR34;print(a[:8]+q+a+q+a[9:]) | Give a code snippet in #ALGOL_68
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program... | 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.
| #Ada | Ada | with Ada.Text_IO;
procedure Damm_Algorithm is
function Damm (Input : in String) return Boolean
is
subtype Digit is Character range '0' .. '9';
Table : constant array (Digit, Digit) of Digit :=
(('0', '3', '1', '7', '5', '9', '8', '6', '4', '2'),
('7', '0', '9', '2', '1', '5', '4... | Give a code snippet in #Ada
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/Resistor_mesh | Resistor mesh |
Task
Given 10×10 grid nodes (as shown in the image) interconnected by 1Ω resistors as shown,
find the resistance between points A and B.
See also
(humor, nerd sniping) xkcd.com cartoon
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | ResistanceMatrix[g_Graph] := With[{n = VertexCount[g], km = KirchhoffMatrix[g]},
Table[ ReplacePart[ Diagonal[ DrazinInverse[ ReplacePart[km, k -> UnitVector[n, k]]]], k -> 0],
{k, n}]
]
rm = ResistanceMatrix[GridGraph[{10, 10}]];
N[rm[[12, 68]], 40] | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Given 10×10 grid nodes (as shown in the image) interconnected by 1Ω resistors as shown,
find the resistance between points A and B.
See also
(humor, nerd sniping) xkcd.com cartoon
| 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... | #Ruby | Ruby |
# run_encode("aaabbbbc") #=> [["a", 3], ["b", 4], ["c", 1]]
def run_encode(string)
string
.chars
.chunk{|i| i}
.map {|kind, array| [kind, array.length]}
end
# run_decode([["a", 3], ["b", 4], ["c", 1]]) #=> "aaabbbbc"
def run_decode(char_counts)
char_counts
.map{|char, count| char * count}
.j... | Give a code snippet in #Ruby
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 funct... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_matching | String matching |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Yabasic | Yabasic |
cadena1$ = "qwertyuiop"
//Determinar si la primera cadena comienza con la segunda cadena
cadena2$ = "qwerty"
if left$(cadena1$, len(cadena2$)) = cadena2$ then
print "'", cadena1$, "' comienza con '", cadena2$, "'"
else
print "'", cadena1$, "' no comienza con '", cadena2$, "'"
end if
//Determinar si la pri... | Give a code snippet in #Yabasic
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 Operation... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort_with_shifting_bounds | Sorting algorithms/Cocktail sort with shifting bounds |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Visual_Basic_.NET | Visual Basic .NET | ' Sorting algorithms/Cocktail sort with shifting bounds - VB.Net
Private Sub Cocktail_Shaker_Sort()
Dim A(20), tmp As Long 'or Integer Long Single Double String
Dim i, beginIdx, endIdx, newBeginIdx, newEndIdx As Integer
'Generate the list
For i = LBound(A) To UBound(A)
A... | Give a code snippet in #Visual_Basic_.NET
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Command-line_arguments | Command-line arguments | Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| #Modula-2 | Modula-2 | MODULE try;
FROM Arguments IMPORT GetArgs, ArgTable, GetEnv;
FROM InOut IMPORT WriteCard, WriteLn, WriteString;
VAR count, item : SHORTCARD;
storage : ArgTable;
BEGIN
GetArgs (count, storage);
WriteString ('Count ='); WriteCard (count, 4); WriteLn;
item := 0;
... | Give a code snippet in #Modula-2
Command-line arguments is part of Short Circuit's Console Program Basics selection.
Scripted main
See also Program name.
For parsing command line arguments intelligently, see Parsing command-line arguments.
Example command line:
myprogram -c "alpha beta" -h "gamma"
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Pell%27s_equation | Pell's equation | Pell's equation (also called the Pell–Fermat equation) is a Diophantine equation of the form:
x2 - ny2 = 1
with integer solutions for x and y, where n is a given non-square positive integer.
Task requirements
find the smallest solution in positive integers to Pell's equation for... | #Python | Python | import math
def solvePell(n):
x = int(math.sqrt(n))
y, z, r = x, 1, x << 1
e1, e2 = 1, 0
f1, f2 = 0, 1
while True:
y = r * z - y
z = (n - y * y) // z
r = (x + y) // z
e1, e2 = e2, e1 + e2 * r
f1, f2 = f2, f1 + f2 * r
a, b = f2 * x + e2, f2
... | Give a code snippet in #Python
Pell's equation (also called the Pell–Fermat equation) is a Diophantine equation of the form:
x2 - ny2 = 1
with integer solutions for x and y, where n is a given non-square positive integer.
Task requirements
find the smallest solution in positive... | 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 ... | #Ruby | Ruby | class Maybe
def initialize(value)
@value = value
end
def map
if @value.nil?
self
else
Maybe.new(yield @value)
end
end
end
Maybe.new(3).map { |n| 2*n }.map { |n| n+1 }
#=> #<Maybe @value=7>
Maybe.new(nil).map { |n| 2*n }.map { |n| n+1 }
#=> #<Maybe @value=nil>
Maybe.new(3).map... | Give a code snippet in #Ruby
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/Colour_bars/Display | Colour bars/Display | Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| #C | C |
#include<conio.h>
#define COLOURS 8
int main()
{
int colour=0,i,j,MAXROW,MAXCOL;
struct text_info tInfo;
gettextinfo(&tInfo);
MAXROW = tInfo.screenheight;
MAXCOL = tInfo.screenwidth;
textbackground(BLACK); //8 colour constants are defined
clrscr();
for(colour=0;colour<COLOURS;colour++)
{
getch();... | Give a code snippet in #C
Task
Display a series of vertical color bars across the width of the display.
The color bars should either use:
the system palette, or
the sequence of colors:
black
red
green
blue
magenta
cyan
yellow
white
| christopher/rosetta-code | |
http://rosettacode.org/wiki/JSON | JSON | Load a JSON string into a data structure.
Also, create a new data structure and serialize it into JSON.
Use objects and arrays (as appropriate for your language)
and make sure your JSON is valid (https://jsonformatter.org).
| #OpenEdge.2FProgress | OpenEdge/Progress | /* using a longchar to read and write to, can also be file, memptr, stream */
DEFINE VARIABLE lcjson AS LONGCHAR NO-UNDO.
/* temp-table defines object, can also be dataset */
DEFINE TEMP-TABLE example
FIELD blue AS INTEGER EXTENT 2
FIELD ocean AS CHARACTER
.
CREATE example.
ASSIGN
example.blue [1] = ... | Give a code snippet in #OpenEdge.2FProgress
Load a JSON string into a data structure.
Also, create a new data structure and serialize it into JSON.
Use objects and arrays (as appropriate for your language)
and make sure your JSON is valid (https://jsonformatter.org).
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic_evaluation | Arithmetic evaluation | Create a program which parses and evaluates arithmetic expressions.
Requirements
An abstract-syntax tree (AST) for the expression must be created from parsing the input.
The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a similar language feature.)
The ... | #Sidef | Sidef | func evalArithmeticExp(s) {
func evalExp(s) {
func operate(s, op) {
s.split(op).map{|c| Number(c) }.reduce(op)
}
func add(s) {
operate(s.sub(/^\+/,'').sub(/\++/,'+'), '+')
}
func subtract(s) {
s.gsub!(/(\+-|-\+)/,'-')
i... | Give a code snippet in #Sidef
Create a program which parses and evaluates arithmetic expressions.
Requirements
An abstract-syntax tree (AST) for the expression must be created from parsing the input.
The AST must be used in evaluation, also, so the input may not be directly evaluated (e.g. by calling eval or a si... | 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... | #Python | Python | >>> import queue
>>> pq = queue.PriorityQueue()
>>> for item in ((3, "Clear drains"), (4, "Feed cat"), (5, "Make tea"), (1, "Solve RC tasks"), (2, "Tax return")):
pq.put(item)
>>> while not pq.empty():
print(pq.get_nowait())
(1, 'Solve RC tasks')
(2, 'Tax return')
(3, 'Clear drains')
(4, 'Feed cat')
(5, 'Ma... | Give a code snippet in #Python
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 pri... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Text | Hello world/Text | Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
Hello world/Web server
| #Draco | Draco | proc nonrec main() void:
writeln("Hello world!")
corp | Give a code snippet in #Draco
Hello world/Text is part of Short Circuit's Console Program Basics selection.
Task
Display the string Hello world! on a text console.
Related tasks
Hello world/Graphical
Hello world/Line Printer
Hello world/Newbie
Hello world/Newline omission
Hello world/Standard error
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #PARI.2FGP | PARI/GP | newpoint(x)={
myT=x;
myS=0;
myN=1;
[myT,myS]/myN
};
addpoint(x)={
myT+=x;
myN++;
myS+=(myN*x-myT)^2/myN/(myN-1);
[myT,myS]/myN
};
addpoints(v)={
print(newpoint(v[1]));
for(i=2,#v,print(addpoint(v[i])));
print("Mean: ",myT/myN);
print("Standard deviation: ",sqrt(myS/myN))
};
addpoints([2,4,4,4,5,... | Give a code snippet in #PARI.2FGP
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 f... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sieve_of_Eratosthenes | Sieve of Eratosthenes | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes algorithm, with the only allowed... | #Scala | Scala | import scala.annotation.tailrec
import scala.collection.parallel.mutable
import scala.compat.Platform
object GenuineEratosthenesSieve extends App {
def sieveOfEratosthenes(limit: Int) = {
val (primes: mutable.ParSet[Int], sqrtLimit) = (mutable.ParSet.empty ++ (2 to limit), math.sqrt(limit).toInt)
@tailrec
... | Give a code snippet in #Scala
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
The Sieve of Eratosthenes is a simple algorithm that finds the prime numbers up to a given integer.
Task
Implement the Sieve of Eratosthenes a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Balanced_brackets | Balanced brackets | Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nest.
Examples
(empty) ... | #REXX | REXX | /*REXX program checks for balanced brackets [ ] ─── some fixed, others random.*/
parse arg seed . /*obtain optional argument from the CL.*/
if datatype(seed,'W') then call random ,,seed /*if specified, then use as RANDOM seed*/
@.=0; yesNo.0= right('not OK', 50) ... | Give a code snippet in #REXX
Task:
Generate a string with N opening brackets [ and with N closing brackets ], in some arbitrary order.
Determine whether the generated string is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-ne... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_to_100 | Sum to 100 | Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particular sum (in this iconic case, ... | #Ruby | Ruby | digits = ("1".."9").to_a
ar = ["+", "-", ""].repeated_permutation(digits.size).filter_map do |op_perm|
str = op_perm.zip(digits).join
str unless str.start_with?("+")
end
res = ar.group_by{|str| eval(str)}
puts res[100] , ""
sum, solutions = res.max_by{|k,v| v.size}
puts "#{sum} has #{solutions.size} solutions... | Give a code snippet in #Ruby
Task
Find solutions to the sum to one hundred puzzle.
Add (insert) the mathematical
operators + or - (plus
or minus) before any of the digits in the
decimal numeric string 123456789 such that the
resulting mathematical expression adds up to a
particular ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Even_or_odd | Even or odd | Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
Divide i by 2. The remainder equals... | #Emacs_Lisp | Emacs Lisp | (require 'cl-lib)
(defun even-or-odd-p (n)
(if (cl-evenp n) 'even 'odd))
(defun even-or-odd-p (n)
(if (zerop (% n 2)) 'even 'odd))
(message "%d is %s" 3 (even-or-oddp 3))
(message "%d is %s" 2 (even-or-oddp 2)) | Give a code snippet in #Emacs_Lisp
Task
Test whether an integer is even or odd.
There is more than one way to solve this task:
Use the even and odd predicates, if the language provides them.
Check the least significant digit. With binary integers, i bitwise-and 1 equals 0 iff i is even, or equals 1 iff i is odd.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_has_all_the_same_characters | Determine if a string has all the same characters | Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each string and its length (as the... | #Ruby | Ruby | strings = ["", " ", "2", "333", ".55", "tttTTT", "4444 444k", "pépé", "🐶🐶🐺🐶", "🎄🎄🎄🎄"]
strings.each do |str|
pos = str.empty? ? nil : str =~ /[^#{str[0]}]/
print "#{str.inspect} (size #{str.size}): "
puts pos ? "first different char #{str[pos].inspect} (#{'%#x' % str[pos].ord}) at position #{pos}." ... | Give a code snippet in #Ruby
Task
Given a character string (which may be empty, or have a length of zero characters):
create a function/procedure/routine to:
determine if all the characters in the string are the same
indicate if or which character is different from the previous character
display each s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Monty_Hall_problem | Monty Hall problem |
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed for the time being.
The game show hos... | #REXX | REXX | /* REXX ***************************************************************
* 30.08.2013 Walter Pachl derived from Java
**********************************************************************/
Call time 'R'
switchWins = 0;
stayWins = 0
Do plays = 1 To 1000000
doors.=0
r=r3()
doors.r=1
choice = r3()
Do Until shown<... | Give a code snippet in #REXX
Suppose you're on a game show and you're given the choice of three doors.
Behind one door is a car; behind the others, goats.
The car and the goats were placed randomly behind the doors before the show.
Rules of the game
After you have chosen a door, the door remains closed for the ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Environment_variables | Environment variables | Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| #Phix | Phix | without js -- none such in a browser, that I know of
?getenv("PATH")
| Give a code snippet in #Phix
Task
Show how to get one of your process's environment variables.
The available variables vary by system; some of the common ones available on Unix include:
PATH
HOME
USER
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Wireworld | Wireworld | Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell transitions happen simultaneous... | #Ceylon | Ceylon | abstract class Cell(shared Character char) of emptyCell | head | tail | conductor {
shared Cell output({Cell*} neighbors) =>
switch (this)
case (emptyCell) emptyCell
case (head) tail
case (tail) conductor
case (conductor) (neighbors.count(head.equals) in... | Give a code snippet in #Ceylon
Wireworld
Conway's Game of Life
It is capable of doing sophisticated computations with appropriate programs
(it is actually Turing complete),
and is much simpler to program for.
A Wireworld arena consists of a Cartesian grid of cells,
each of which can be in one of four states.
All cell... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring/Top_and_tail | Substring/Top and tail | The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
If the program uses UTF-8 or UTF... | #NewLISP | NewLISP | (let (str "rosetta")
;; strip first char
(println (1 str))
;; strip last char
(println (0 -1 str))
;; strip both first and last characters
(println (1 -1 str))) | Give a code snippet in #NewLISP
The task is to demonstrate how to remove the first and last characters from a string.
The solution should demonstrate how to obtain the following results:
String with first character removed
String with last character removed
String with both the first and last characters removed
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nim_game | Nim game | Nim game
You are encouraged to solve this task according to the task description, using any language you may know.
Nim is a simple game where the second player ─── if they know the trick ─── will always win.
The game has only 3 rules:
start with 12 tokens
each player takes 1, 2, or 3 tokens in tur... | #Applesoft_BASIC | Applesoft BASIC | 0ST$(0)="YOU MUST TAKE 1, 2, OR 3 TOKENS.":FORHEAP=12TO1STEP-4:PRINT"THERE ARE "HEAP" TOKENS REMAINING.":FORI=0TO1:INPUT"HOW MANY WOULD YOU LIKE TO TAKE?";T%:I=T%>0ANDT%<4:PRINTST$(I):NEXTI:PRINT"ON MY TURN I WILL TAKE "4-T%" TOKENS.":NEXTHEAP | Give a code snippet in #Applesoft_BASIC
Nim game
You are encouraged to solve this task according to the task description, using any language you may know.
Nim is a simple game where the second player ─── if they know the trick ─── will always win.
The game has only 3 rules:
start with 12 tokens
each pla... | 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.
| #Forth | Forth | Name Type Description
---------------------------------------------
TIB integer Terminal Input Buffer address
U0 integer current user area address
>IN integer holds offset into TIB, used for parsing
BASE integer holds number conversion radix
STATE integer holds compil... | Give a code snippet in #Forth
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/Scope/Function_names_and_labels | Scope/Function names and labels | Task
Explain or demonstrate the levels of visibility of function names and labels within the language.
See also
Variables for levels of scope relating to visibility of program variables
Scope modifiers for general scope modification facilities
| #jq | jq | def NAME:
def NAME: 2;
1, NAME; # this calls the inner function, not the outer function
NAME # => 1, 2 | Give a code snippet in #jq
Task
Explain or demonstrate the levels of visibility of function names and labels within the language.
See also
Variables for levels of scope relating to visibility of program variables
Scope modifiers for general scope modification facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Get_system_command_output | Get system command output | Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| #PureBasic | PureBasic | If OpenConsole("ls")
rp=RunProgram("ls", "-l", "",#PB_Program_Open|#PB_Program_Read)
While ProgramRunning(rp)
If AvailableProgramOutput(rp)
r$+ReadProgramString(rp)+#LF$
EndIf
Wend
CloseProgram(rp)
PrintN(r$)
Input()
EndIf
| Give a code snippet in #PureBasic
Task
Execute a system command and get its output into the program. The output may be stored in any kind of collection (array, list, etc.).
Related task
Execute a system command
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Increment_a_numerical_string | Increment a numerical string | Task
Increment a numerical string.
| #Maple | Maple | s := "12345";
s := convert(parse(s)+1, string); | Give a code snippet in #Maple
Task
Increment a numerical string.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Simple_moving_average | Averages/Simple moving average | Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average is a method for computing an avera... | #Bracmat | Bracmat | ( ( I
= buffer
. (new$=):?freshEmptyBuffer
&
' ( buffer avg
. ( avg
= L S n
. 0:?L:?S
& whl
' ( !arg:%?n ?arg
& !n+!S:?S
& 1+!L:?L
)
... | Give a code snippet in #Bracmat
Computing the simple moving average of a series of numbers.
Task[edit]
Create a stateful function/class/instance that takes a period and returns a routine that takes a number as argument and returns a simple moving average of its arguments so far.
Description
A simple moving average i... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_triangle | Sierpinski triangle | Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
* * * *
... | #FOCAL | FOCAL | 01.10 A "ORDER",O;S S=2^(O+1)
01.20 F X=0,S;S L(X)=0
01.30 S L(S/2)=1
01.40 F I=1,S/2;D 2;D 3
01.90 Q
02.10 F X=1,S-1;D 2.3
02.20 T !;R
02.30 I (L(X)),2.4,2.5
02.40 T " "
02.50 T "*"
03.10 F X=0,S;S K(X)=FABS(L(X-1)-L(X+1))
03.20 F X=0,S;S L(X)=K(X) | Give a code snippet in #FOCAL
Task
Produce an ASCII representation of a Sierpinski triangle of order N.
Example
The Sierpinski triangle of order 4 should look like this:
*
* *
* *
* * * *
* *
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/A%2BB | A+B | A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated by space(s):
(
−
1000
≤... | #Picat | Picat |
go =>
println("Write two integers (and CR)"),
println(read_int()+read_int()).
| Give a code snippet in #Picat
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separate... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Nested | Loops/Nested | Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is met.
Specifically, this task als... | #Fantom | Fantom | class Main
{
public static Void main ()
{
rows := 10
cols := 10
// create and fill an array of given size with random numbers
Int[][] array := [,]
rows.times
{
row := [,]
cols.times { row.add(Int.random(1..20)) }
array.add (row)
}
// now do the search
try
{
... | Give a code snippet in #Fantom
Show a nested loop which searches a two-dimensional array filled with random numbers uniformly distributed over
[
1
,
…
,
20
]
{\displaystyle [1,\ldots ,20]}
.
The loops iterate rows and columns of the array printing the elements until the value
20
{\displaystyle 20}
is m... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack_traces | Stack traces | Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the platform) the current call stack.... | #Phix | Phix | constant W = machine_word(),
{RTN,PREVEBP} = iff(W=4?{8,20}:{16,40})
procedure show_stack()
sequence symtab, symtabN
integer rtn
atom prev_ebp
#ilASM{
[32]
lea edi,[symtab]
call :%opGetST -- [edi]=symtab (ie our local:=the real symtab)
mov edi,[ebp+20] ... | Give a code snippet in #Phix
Many programming languages allow for introspection of the current call stack environment. This can be for a variety of purposes such as enforcing security checks, debugging, or for getting access to the stack frame of callers.
Task
Print out (in a manner considered suitable for the pla... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Statistics/Basic | Statistics/Basic | Statistics is all about large groups of numbers.
When talking about a set of sampled data, most frequently used is their mean value and standard deviation (stddev).
If you have set of data
x
i
{\displaystyle x_{i}}
where
i
=
1
,
2
,
…
,
n
{\displaystyle i=1,2,\ldots ,n\,\!}
, the mean is
x
¯... | #Scala | Scala | def mean(a:Array[Double])=a.sum / a.size
def stddev(a:Array[Double])={
val sum = a.fold(0.0)((a, b) => a + math.pow(b,2))
math.sqrt((sum/a.size) - math.pow(mean(a),2))
}
def hist(a:Array[Double]) = {
val grouped=(SortedMap[Double, Array[Double]]() ++ (a groupBy (x => math.rint(x*10)/10)))
grouped.map(v => (... | Give a code snippet in #Scala
Statistics is all about large groups of numbers.
When talking about a set of sampled data, most frequently used is their mean value and standard deviation (stddev).
If you have set of data
x
i
{\displaystyle x_{i}}
where
i
=
1
,
2
,
…
,
n
{\displaystyle i=1,2,\ldots ,n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Numerical_integration/Gauss-Legendre_Quadrature | Numerical integration/Gauss-Legendre Quadrature |
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting function
W
(
x
)
{\displaystyle ... | #J | J | NB. returns coefficents for yth-order Legendre polynomial
getLegendreCoeffs=: verb define M.
if. y<:1 do. 1 {.~ - y+1 return. end.
(%~ <:@(,~ +:) -/@:* (0;'') ,&> [: getLegendreCoeffs&.> -&1 2) y
)
getPolyRoots=: 1 {:: p. NB. returns the roots of a polynomial
getGaussLegendreWeights... | Give a code snippet in #J
In a general Gaussian quadrature rule, an definite integral of
f
(
x
)
{\displaystyle f(x)}
is first approximated over the interval
[
−
1
,
1
]
{\displaystyle [-1,1]}
by a polynomial approximable function
g
(
x
)
{\displaystyle g(x)}
and a known weighting function
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Long_multiplication | Long multiplication | Task
Explicitly implement long multiplication.
This is one possible approach to arbitrary-precision integer algebra.
For output, display the result of 264 * 264.
Optionally, verify your result against builtin arbitrary precision support.
The decimal representation of 264 is:
18,446,744,073,709,551,61... | #PARI.2FGP | PARI/GP | long(a,b)={
a=eval(Vec(a));
b=eval(Vec(b));
my(c=vector(#a+#b),carry=0);
for(i=1,#a,
for(j=1,#b,
c[i+j]+=a[i]*b[j]
)
);
forstep(i=#c,1,-1,
c[i] += carry;
carry = c[i] \ 10;
c[i] = c[i] % 10
);
for(i=1,#c,
if(c[i], return(concat(apply(s->Str(s),vector(#c+1-i,j,c[i+j-1])))))
... | Give a code snippet in #PARI.2FGP
Task
Explicitly implement long multiplication.
This is one possible approach to arbitrary-precision integer algebra.
For output, display the result of 264 * 264.
Optionally, verify your result against builtin arbitrary precision support.
The decimal representation of 26... | 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 ... | #Eiffel | Eiffel | class
APPLICATION
create
make
feature {NONE} -- Initialization
make
-- Run application.
do
create input_file.make_open_read ("input.txt")
create output_file.make_open_write ("output.txt")
from
input_file.read_character
... | Give a code snippet in #Eiffel
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Determine_if_a_string_is_numeric | Determine if a string is numeric | Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string operations:
Metrics
Array length
String length
Cop... | #mIRC_Scripting_Language | mIRC Scripting Language | var %value = 3
if (%value isnum) {
echo -s %value is numeric.
} | Give a code snippet in #mIRC_Scripting_Language
Task
Create a boolean function which takes in a string and tells whether it is a numeric string (floating point and negative numbers included) in the syntax the language uses for numeric literals or numbers converted from strings.
Other tasks related to string opera... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Random_sentence_from_book | Random sentence from book | Read in the book "The War of the Worlds", by H. G. Wells.
Skip to the start of the book, proper.
Remove extraneous punctuation, but keep at least sentence-ending punctuation characters . ! and ?
Keep account of what words follow words and how many times it is seen, (treat sentence terminators as words too).
Keep a... | #Julia | Julia | """ weighted random pick of items in a Dict{String, Int} where keys are words, values counts """
function weightedrandompick(dict, total)
n = rand(1:total)
for (key, value) in dict
n -= value
if n <= 0
return key
end
end
return last(keys(dict))
end
let
""" Read ... | Give a code snippet in #Julia
Read in the book "The War of the Worlds", by H. G. Wells.
Skip to the start of the book, proper.
Remove extraneous punctuation, but keep at least sentence-ending punctuation characters . ! and ?
Keep account of what words follow words and how many times it is seen, (treat sentence ter... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Cocktail_sort | Sorting algorithms/Cocktail 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
... | #jq | jq | # In case your jq does not have "until" defined:
def until(cond; next):
def _until:
if cond then . else (next|_until) end;
_until; | Give a code snippet in #jq
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/JortSort | JortSort |
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
... | #Java | Java | public class JortSort {
public static void main(String[] args) {
System.out.println(jortSort(new int[]{1, 2, 3}));
}
static boolean jortSort(int[] arr) {
return true;
}
} | Give a code snippet in #Java
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Read_a_PPM_file | Bitmap/Read a PPM file | Using the data storage type defined on this page for raster images, read an image from a PPM file (binary P6 prefered).
(Read the definition of PPM file on Wikipedia.)
Task: Use write ppm file solution and grayscale image solution with this one in order to convert a color image to grayscale one.
| #Mathematica.2F_Wolfram_Language | Mathematica/ Wolfram Language | Import["file.ppm","PPM"]
| Give a code snippet in #Mathematica.2F_Wolfram_Language
Using the data storage type defined on this page for raster images, read an image from a PPM file (binary P6 prefered).
(Read the definition of PPM file on Wikipedia.)
Task: Use write ppm file solution and grayscale image solution with this one in order to conve... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_IO | Bitwise IO | The aim of this task is to write functions (or create a class if your
language is Object Oriented and you prefer) for reading and writing sequences of
bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence
"S", "T", "R", "I", "N", "G", the output of a "print" of the bits ... | #PureBasic | PureBasic | Structure fileDataBits
bitsToWrite.i
bitsToRead.i
outputByte.i
inputByte.i
EndStructure
#BitsPerByte = SizeOf(Byte) * 8
#BitsPerInteger = SizeOf(Integer) * 8
Global Dim fileBitMask(8)
Define i, x
For i = 0 To 8
fileBitMask(i) = x
x = (x << 1) + 1
Next
Global NewMap fileDataBits.fileDataBits()
Procedure ... | Give a code snippet in #PureBasic
The aim of this task is to write functions (or create a class if your
language is Object Oriented and you prefer) for reading and writing sequences of
bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence
"S", "T", "R", "I", "N", "G", t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_composition | Function composition | Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function g to x.
Example
compose... | #Lingo | Lingo | -- in some movie script
----------------------------------------
-- Composes 2 call-functions, returns a new call-function
-- @param {symbol|instance} f
-- @param {symbol|instance} g
-- @return {instance}
----------------------------------------
on compose (f, g)
return script("Composer").new(f, g)
end | Give a code snippet in #Lingo
Task
Create a function, compose, whose two arguments f and g, are both functions with one argument.
The result of compose is to be a function of one argument, (lets call the argument x), which works like applying function f to the result of applying function g ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_float_arrays_to_a_text_file | Write float arrays to a text file | Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {1, 2, 3, 1e11};
y = {1, 1.41421356... | #Delphi | Delphi |
program Write_float_arrays_to_a_text_file;
{$APPTYPE CONSOLE}
uses
System.SysUtils,
System.IoUtils;
function ToString(v: TArray<Double>): TArray<string>;
var
fmt: TFormatSettings;
begin
fmt := TFormatSettings.Create('en-US');
SetLength(Result, length(v));
for var i := 0 to High(v) do
Result[i]... | Give a code snippet in #Delphi
Task
Write two equal-sized numerical arrays 'x' and 'y' to
a two-column text file named 'filename'.
The first column of the file contains values from an 'x'-array with a
given 'xprecision', the second -- values from 'y'-array with 'yprecision'.
For example, considering:
x = {1, 2,... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Insertion_sort | Sorting algorithms/Insertion 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
... | #Qi | Qi | (define insert
X [] -> [X]
X [Y|Ys] -> [X Y|Ys] where (<= X Y)
X [Y|Ys] -> [Y|(insert X Ys)])
(define insertion-sort
[] -> []
[X|Xs] -> (insert X (insertion-sort Xs)))
(insertion-sort [6 8 5 9 3 2 1 4 7])
| Give a code snippet in #Qi
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/Binary_search | Binary search | A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a secret number, and will only tell the p... | #Python | Python | def binary_search(l, value):
low = 0
high = len(l)-1
while low <= high:
mid = (low+high)//2
if l[mid] > value: high = mid-1
elif l[mid] < value: low = mid+1
else: return mid
return -1 | Give a code snippet in #Python
A binary search divides a range of values into halves, and continues to narrow down the field of search until the unknown value is found. It is the classic example of a "divide and conquer" algorithm.
As an analogy, consider the children's game "guess a number." The scorer has a secret ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Honeycombs | Honeycombs | The task is to produce a matrix of 20 hexagon shaped widgets in a honeycomb arrangement. The matrix should be arranged in such a manner that there are five
columns of four hexagons. The hexagons in columns one, three and five are aligned horizontally, whereas the hexagons in columns two and four occupy a lower position... | #ActionScript | ActionScript |
package {
import flash.display.GraphicsPathCommand;
import flash.display.Sprite;
import flash.text.TextField;
import flash.text.TextFieldAutoSize;
import flash.text.TextFormat;
/**
* A honeycomb.
*/
public class Honeycomb extends Sprite {
/**
* The sine of... | Give a code snippet in #ActionScript
The task is to produce a matrix of 20 hexagon shaped widgets in a honeycomb arrangement. The matrix should be arranged in such a manner that there are five
columns of four hexagons. The hexagons in columns one, three and five are aligned horizontally, whereas the hexagons in column... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rot-13 | Rot-13 |
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 encoding of every line of inpu... | #Nim | Nim | import strutils
proc rot13(c: char): char =
case toLowerAscii(c)
of 'a'..'m': chr(ord(c) + 13)
of 'n'..'z': chr(ord(c) - 13)
else: c
for line in stdin.lines:
for c in line:
stdout.write rot13(c)
stdout.write "\n" | Give a code snippet in #Nim
Task
Implement a rot-13 function (or procedure, class, subroutine, or other "callable" object as appropriate to your programming environment).
Optionally wrap this function in a utility program (like tr, which acts like a common UNIX utility, performing a line-by-line rot-13 e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sequence_of_primes_by_trial_division | Sequence of primes by trial division | Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for being a prime by trying to divide it by... | #Eiffel | Eiffel |
class
APPLICATION
create
make
feature
make
do
sequence (1, 27)
end
sequence (lower, upper: INTEGER)
-- Sequence of primes from 'lower' to 'upper'.
require
lower_positive: lower > 0
upper_positive: upper > 0
lower_smaller: lower < upper
local
i: INTEGER
do
io.put_string ("Seq... | Give a code snippet in #Eiffel
Sequence of primes by trial division
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Generate a sequence of primes by means of trial division.
Trial division is an algorithm where a candidate number is tested for being a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Roots_of_unity | Roots of unity | The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| #RLaB | RLaB | // specify polynomial
>> n = 10;
>> a = zeros(1,n+1); a[1] = 1; a[n+1] = -1;
>> polyroots(a)
radius roots success
>> polyroots(a).roots
-0.309016994 + 0.951056516i
-0.809016994 + 0.587785252i
-1 + 5.95570041e-23i
-0.809016994 - 0.587785252i
-0.309016994 - 0.951056516i
... | Give a code snippet in #RLaB
The purpose of this task is to explore working with complex numbers.
Task
Given n, find the nth roots of unity.
| 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... | #BASIC256 | BASIC256 | function min(a, b)
if a < b then return a else return b
end function
function d6()
#simulates a marked regular hexahedron coming to rest on a plane
return 1 + int(rand * 6)
end function
function roll_stat()
#rolls four dice, returns the sum of the three highest
a = d6() : b = d6() : c = d6() : d = d6()
retur... | Give a code snippet in #BASIC256
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Password_generator | Password generator | Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+,-./:;<=>?@[]^_{|}~
(the above ch... | #PureBasic | PureBasic | EnableExplicit
Procedure.b CheckPW(pw.s)
Define flag.b=#True,
tmp.b=#False,
c.c,
s.s,
i.i
For c='a' To 'z'
tmp=Bool(FindString(pw,Chr(c)))
If tmp : Break : EndIf
Next
flag & tmp
tmp=#False
For c='A' To 'Z'
tmp=Bool(FindString(pw,Chr(c)))
If tmp : B... | Give a code snippet in #PureBasic
Create a password generation program which will generate passwords containing random ASCII characters from the following groups:
lower-case letters: a ──► z
upper-case letters: A ──► Z
digits: 0 ──► 9
other printable characters: !"#$%&'()*+... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_a_list_of_object_identifiers | Sort a list of object identifiers |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Phixmonti | Phixmonti | include ..\Utilitys.pmt
( "1.3.6.1.4.1.11.2.17.19.3.4.0.10"
"1.3.6.1.4.1.11.2.17.5.2.0.79"
"1.3.6.1.4.1.11.2.17.19.3.4.0.4"
"1.3.6.1.4.1.11150.3.4.0.1"
"1.3.6.1.4.1.11.2.17.19.3.4.0.1"
"1.3.6.1.4.1.11150.3.4.0" )
len for
var i
i get "." " " subst split
len for
var j
j get tonum j se... | Give a code snippet in #Phixmonti
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quic... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sierpinski_carpet | Sierpinski carpet | Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## # # ## # # #
### ###### ... | #11l | 11l | F sierpinski_carpet(n)
V carpet = [String(‘#’)]
L 1..n
carpet = carpet.map(x -> x‘’x‘’x)
[+] carpet.map(x -> x‘’x.replace(‘#’, ‘ ’)‘’x)
[+] carpet.map(x -> x‘’x‘’x)
R carpet.join("\n")
print(sierpinski_carpet(3)) | Give a code snippet in #11l
Task
Produce a graphical or ASCII-art representation of a Sierpinski carpet of order N.
For example, the Sierpinski carpet of order 3 should look like this:
###########################
# ## ## ## ## ## ## ## ## #
###########################
### ###### ###### ###
# # # ## #... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #TXR | TXR | @(cases)
hey @a
how are you
@(or)
hey @b
long time no see
@(end) | Give a code snippet in #TXR
Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Inheritance/Single | Inheritance/Single | This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent types.
Usually inherited properties... | #Fortran | Fortran | module anim
type animal
end type animal
type, extends(animal) :: dog
end type dog
type, extends(animal) :: cat
end type cat
type, extends(dog) :: lab
end type lab
type, extends(dog) :: collie
end type collie
end module anim | Give a code snippet in #Fortran
This task is about derived types; for implementation inheritance, see Polymorphism.
Inheritance is an operation of type algebra that creates a new type from one or several parent types.
The obtained type is called derived type.
It inherits some of the properties of its parent typ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Comb_sort | Sorting algorithms/Comb sort | Sorting algorithms/Comb sort
You are encouraged to solve this task according to the task description, using any language you may know.
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algor... | #ARM_Assembly | ARM Assembly |
/* ARM assembly Raspberry PI */
/* program combSort.s */
/* REMARK 1 : this program use routines in a include file
see task Include a file language arm assembly
for the routine affichageMess conversion10
see at end of this program the instruction include */
/* for constantes see task include a file ... | Give a code snippet in #ARM_Assembly
Sorting algorithms/Comb sort
You are encouraged to solve this task according to the task description, using any language you may know.
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic/Rational | Arithmetic/Rational | Task
Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language.
Example
Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as per a rational number).
Fur... | #Ada | Ada | generic
type Number is range <>;
package Generic_Rational is
type Rational is private;
function "abs" (A : Rational) return Rational;
function "+" (A : Rational) return Rational;
function "-" (A : Rational) return Rational;
function Inverse (A : Rational) return Rational;
function "+"... | Give a code snippet in #Ada
Task
Create a reasonably complete implementation of rational arithmetic in the particular language using the idioms of the language.
Example
Define a new type called frac with binary operator "//" of two integers that returns a structure made up of the numerator and the denominator (as... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Truncatable_primes | Truncatable primes | A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number.
Examples
The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime.
The number 7393 is a right-truncatable prime as the numbers 7393, 7... | #Go | Go | package main
import "fmt"
func main() {
sieve(1e6)
if !search(6, 1e6, "left", func(n, pot int) int { return n % pot }) {
panic("997?")
}
if !search(6, 1e6, "right", func(n, _ int) int { return n / 10 }) {
panic("7393?")
}
}
var c []bool
func sieve(ss int) {
c = make([]boo... | Give a code snippet in #Go
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number.
Examples
The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime.
The number 7393 is a right-truncatable ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Exponentiation_operator | Exponentiation operator | Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedure) overloading, then an ov... | #R | R | # Method
pow <- function(x, y)
{
x <- as.numeric(x)
y <- as.integer(y)
prod(rep(x, y))
}
#Operator
"%pow%" <- function(x,y) pow(x,y)
pow(3, 4) # 81
2.5 %pow% 2 # 6.25 | Give a code snippet in #R
Most programming languages have a built-in implementation of exponentiation.
Task
Re-implement integer exponentiation for both intint and floatint as both a procedure, and an operator (if your language supports operator definition).
If the language supports operator (or procedu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Sleep_sort | Sorting algorithms/Sleep sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Lua | Lua | function sleeprint(n)
local t0 = os.time()
while os.time() - t0 <= n do
coroutine.yield(false)
end
print(n)
return true
end
coroutines = {}
for i=1, #arg do
wrapped = coroutine.wrap(sleeprint)
table.insert(coroutines, wrapped)
wrapped(tonumber(arg[i]))
end
done = false
while not done do
done =... | Give a code snippet in #Lua
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/Sutherland-Hodgman_polygon_clipping | Sutherland-Hodgman polygon clipping | The Sutherland-Hodgman clipping algorithm finds the polygon that is the intersection between an arbitrary polygon (the “subject polygon”) and a convex polygon (the “clip polygon”).
It is used in computer graphics (especially 2D graphics) to reduce the complexity of a scene being displayed by eliminating parts of a... | #FreeBASIC | FreeBASIC |
Type Point
As Double x,y
End Type
Type Line
As Point s,f'start/finish
End Type
Function isleft(L As Line,p As Point) As Long
Return -Sgn((L.s.x-L.f.x)*(p.y-L.f.y)-(p.x-L.f.x)*(L.s.y-L.f.y))
End Function
Function segmentintersections(L1 As Line,L2 As Line) As Long
If isleft(L2,L1.s) = is... | Give a code snippet in #FreeBASIC
The Sutherland-Hodgman clipping algorithm finds the polygon that is the intersection between an arbitrary polygon (the “subject polygon”) and a convex polygon (the “clip polygon”).
It is used in computer graphics (especially 2D graphics) to reduce the complexity of a scene being ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arrays | Arrays | This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and retrieve an element (if available,... | #C.2B.2B | C++ | #include <array>
#include <vector>
// These headers are only needed for the demonstration
#include <algorithm>
#include <iostream>
#include <iterator>
#include <string>
// This is a template function that works for any array-like object
template <typename Array>
void demonstrate(Array& array)
{
// Array element a... | Give a code snippet in #C.2B.2B
This task is about arrays.
For hashes or associative arrays, please see Creating an Associative Array.
For a definition and in-depth discussion of what an array is, see Array.
Task
Show basic array syntax in your language.
Basically, create an array, assign a value to it, and ret... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #JavaScript | JavaScript | console.log(new Date()) // => Sat, 28 May 2011 08:22:53 GMT
console.log(Date.now()) // => 1306571005417 // Unix epoch | Give a code snippet in #JavaScript
Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Arithmetic-geometric_mean | Arithmetic-geometric mean |
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Write a function to compute the arithmetic-geomet... | #8th | 8th | : epsilon 1.0e-12 ;
with: n
: iter \ n1 n2 -- n1 n2
2dup * sqrt >r + 2 / r> ;
: agn \ n1 n2 -- n
repeat iter 2dup epsilon ~= not while! drop ;
"agn(1, 1/sqrt(2)) = " . 1 1 2 sqrt / agn "%.10f" s:strfmt . cr
;with
bye
| Give a code snippet in #8th
This page uses content from Wikipedia. The original article was at Arithmetic-geometric mean. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance)
Task
Write a function to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/One-dimensional_cellular_automata | One-dimensional cellular automata | Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the current generation.
If, in the follow... | #PureBasic | PureBasic | EnableExplicit
Dim cG.i(21)
Dim nG.i(21)
Define.i n, Gen
DataSection
Data.i 0,1,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,0,0
EndDataSection
For n=1 To 20
Read.i cG(n)
Next
OpenConsole()
Repeat
Print("Generation "+Str(Gen)+": ")
For n=1 To 20
Print(Chr(95-cG(n)*60))
Next
Gen +1
PrintN("")
For n=1 To 20
... | Give a code snippet in #PureBasic
Assume an array of cells with an initial distribution of live and dead cells,
and imaginary cells off the end of the array having fixed values.
Cells in the next generation of the array are calculated based on the value of the cell and its left and right nearest neighbours in the cur... | christopher/rosetta-code | |
http://rosettacode.org/wiki/SHA-1 | SHA-1 | SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to identify commits.
A US government... | #FreeBASIC | FreeBASIC | ' version 18-10-2016
' started with SHA-1/FIPS-180-1
' but used the BBC BASIC native version to finish.
' compile with: fbc -s console
Function SHA_1(test_str As String) As String
Dim As String message = test_str ' strings are passed as ByRef's
Dim As Long i, j
Dim As UByte Ptr ww1
Dim As UInteger<32>... | Give a code snippet in #FreeBASIC
SHA-1 or SHA1 is a one-way hash function;
it computes a 160-bit message digest.
SHA-1 often appears in security protocols; for example,
many HTTPS websites use RSA with SHA-1 to secure their connections.
BitTorrent uses SHA-1 to verify downloads.
Git and Mercurial use SHA-1 digests to... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitwise_IO | Bitwise IO | The aim of this task is to write functions (or create a class if your
language is Object Oriented and you prefer) for reading and writing sequences of
bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence
"S", "T", "R", "I", "N", "G", the output of a "print" of the bits ... | #Raku | Raku | sub encode-ascii(Str $s) {
my @b = flat $s.ords».fmt("%07b")».comb;
@b.push(0) until @b %% 8; # padding
Buf.new: gather while @b { take reduce * *2+*, (@b.pop for ^8) }
}
sub decode-ascii(Buf $b) {
my @b = flat $b.list».fmt("%08b")».comb;
@b.shift until @b %% 7; # remove padding
@b = gathe... | Give a code snippet in #Raku
The aim of this task is to write functions (or create a class if your
language is Object Oriented and you prefer) for reading and writing sequences of
bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence
"S", "T", "R", "I", "N", "G", the ou... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix_multiplication | Matrix multiplication | Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| #Seed7 | Seed7 | const type: matrix is array array float;
const func matrix: (in matrix: left) * (in matrix: right) is func
result
var matrix: result is matrix.value;
local
var integer: i is 0;
var integer: j is 0;
var integer: k is 0;
var float: accumulator is 0.0;
begin
if length(left[1]) <> length(rig... | Give a code snippet in #Seed7
Task
Multiply two matrices together.
They can be of any dimensions, so long as the number of columns of the first matrix is equal to the number of rows of the second matrix.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Bitmap/Histogram | Bitmap/Histogram | Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh... | #Octave | Octave | function h = imagehistogram(imago)
if ( isgray(imago) )
for j = 0:255
h(j+1) = numel(imago( imago == j ));
endfor
else
error("histogram on gray img only");
endif
endfunction
% test
im = jpgread("Lenna100.jpg");
img = rgb2gray(im);
h = imagehistogram(img);
% let's try to show the histogram
bar(... | Give a code snippet in #Octave
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must h... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Bead_sort | Sorting algorithms/Bead 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
... | #Python | Python |
#!/bin/python3
from itertools import zip_longest
# This is wrong, it works only on specific examples
def beadsort(l):
return list(map(sum, zip_longest(*[[1] * e for e in l], fillvalue=0)))
# Demonstration code:
print(beadsort([5,3,1,7,4,1,1]))
| Give a code snippet in #Python
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick s... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Recaman%27s_sequence | Recaman's sequence | The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Task
Generate and show here the... | #Draco | Draco | proc nonrec find([*] int A; word top; int n) bool:
word i;
bool found;
i := 0;
found := false;
while i < top and not found do
found := A[i] = n;
i := i + 1
od;
found
corp
proc nonrec gen_next([*] int A; word n) int:
int add, sub;
add := A[n-1] + n;
sub := A[n-1]... | Give a code snippet in #Draco
The Recamán's sequence generates Natural numbers.
Starting from a(0)=0, the n'th term a(n), where n>0, is the previous term minus n i.e a(n) = a(n-1) - n but only if this is both positive and has not been previousely generated.
If the conditions don't hold then a(n) = a(n-1) + n.
Ta... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Assertions | Assertions | Assertions are a way of breaking out of code when there is an error or an unexpected input.
Some languages throw exceptions and some treat it as a break point.
Task
Show an assertion in your language by asserting that an integer variable is equal to 42.
| #Picat | Picat | go =>
%
% Test predicates
%
S = "ablewasiereisawelba",
assert("test1",$is_palindrome(S)),
assert_failure("test2",$not is_palindrome(S)),
assert("test3",$member(1,1..10)),
assert_failure("test4",$member(1,1..10)), % bad test
nl,
%
% Test functions
%
assert("test5",$2+2,4),
assert_fa... | Give a code snippet in #Picat
Assertions are a way of breaking out of code when there is an error or an unexpected input.
Some languages throw exceptions and some treat it as a break point.
Task
Show an assertion in your language by asserting that an integer variable is equal to 42.
| 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... | #REXX | REXX | /*REXX pgm demonstrates how to achieve movement of the terminal cursor. */
parse value scrsize() with sd sw /*find the display screen size. */
parse value cursor() with row col /*find where the cursor is now. */
colL=col-1; if colL==0 then colL=sw /*prepare to move cursor to left.*/
call cursor row,... | Give a code snippet in #REXX
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 (witho... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Queue/Usage | Queue/Usage |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queues, see the FIFO task.)
Ope... | #Java | Java | import java.util.LinkedList;
import java.util.Queue;
...
Queue<Integer> queue = new LinkedList<Integer>();
System.out.println(queue.isEmpty()); // empty test - true
// queue.remove(); // would throw NoSuchElementException
queue.add(1);
queue.add(2);
queue.add(3);
System.out.println(queue); // ... | Give a code snippet in #Java
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Illustration of FIFO behavior
Task
Create a queue data structure and demonstrate its operations.
(For implementations of queu... | 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
... | #MUMPS | MUMPS | SEDOL
NEW A,B
SEDOL1
READ !,"Enter the first 6 digits of a SEDOL: ",A
SET B=$$SEDOLCHK(A)
WRITE !,$SELECT($LENGTH(B)=1:"Full SEDOL is "_A_B,1:B)
GOTO SEDOL1
QUIT
SEDOLCHK(STOCK)
NEW WT,VAL,I,CHK,C,FLAG
SET WT="1317391",VAL=0,FLAG=0
FOR I=1:1:6 SET C=$$TOUPPER($EXTRACT(STOCK,I)),VAL=VAL+($$SEDVAL(C)*$EXTRACT(WT... | Give a code snippet in #MUMPS
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... | 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.
| #Cach.C3.A9_ObjectScript | Caché ObjectScript | Class Utils.Check [ Abstract ]
{
ClassMethod Damm(num As %Integer, mode As %Integer = 1) As %Integer
{
TRY {
I mode=0 RETURN ..Damm(num,2)=0
S res=0, str=num
S table=[
[0, 3, 1, 7, 5, 9, 8, 6, 4, 2],
[7, 0, 9, 2, 1, 5, 4, 8, 6, 3],
[4, 2, 0, 6, 8, 7, 1, 3, 5, 9],
[1, 7, 5, 0, 9, 8, 3, 4, 2, 6],
... | Give a code snippet in #Cach.C3.A9_ObjectScript
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/Set_of_real_numbers | Set of real numbers | All real numbers form the uncountable set ℝ. Among its subsets, relatively simple are the convex sets, each expressed as a range between two real numbers a and b where a ≤ b. There are actually four cases for the meaning of "between", depending on open or closed boundary:
[a, b]: {x | a ≤ x and x ≤ b }
(a, b): {x | ... | #Tcl | Tcl | package require Tcl 8.5
proc inRange {x range} {
lassign $range a aClosed b bClosed
expr {($aClosed ? $a<=$x : $a<$x) && ($bClosed ? $x<=$b : $x<$b)}
}
proc normalize {A} {
set A [lsort -index 0 -real [lsort -index 1 -integer -decreasing $A]]
for {set i 0} {$i < [llength $A]} {incr i} {
lassign [lind... | Give a code snippet in #Tcl
All real numbers form the uncountable set ℝ. Among its subsets, relatively simple are the convex sets, each expressed as a range between two real numbers a and b where a ≤ b. There are actually four cases for the meaning of "between", depending on open or closed boundary:
[a, b]: {x | a ≤... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Remove_lines_from_a_file | Remove lines from a file | Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to remove the first two lines from th... | #BASIC | BASIC |
' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' '
' Remove File Lines V1.1 '
' '
' Developed by A. David Garza Marín in VB-DOS for '
' RosettaCode. November 30, 2016. '
' ... | Give a code snippet in #BASIC
Task
Remove a specific line or a number of lines from a file.
This should be implemented as a routine that takes three parameters (filename, starting line, and the number of lines to be removed).
For the purpose of this task, line numbers and the number of lines start at one, so to rem... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Function_definition | Function definition | A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract from showing how functions are ... | #Forth | Forth | : fmultiply ( F: a b -- F: c ) F* ;
: multiply ( a b -- c ) * ; | Give a code snippet in #Forth
A function is a body of code that returns a value.
The value returned may depend on arguments provided to the function.
Task
Write a definition of a function called "multiply" that takes two arguments and returns their product.
(Argument types should be chosen so as not to distract ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #ALGOL_W | ALGOL W | begin
long real sum, sum2;
integer n;
long real procedure sd (long real value x) ;
begin
sum := sum + x;
sum2 := sum2 + (x*x);
n := n + 1;
if n = 0 then 0 else longsqrt(sum2/n - sum*sum/n/n)
end sd;
sum := sum2 := n := 0;
r_format := "A"; r_w... | Give a code snippet in #ALGOL_W
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 fun... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Cheryl%27s_birthday | Cheryl's birthday | Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is.
Cheryl gave them a list of ten possible dates:
May 15, May 16, May 19
June 17, June 18
July 14, July 16
August 14, August 15, August 17
Cheryl then tells Albert the month of birth, ... | #Raku | Raku | my @dates =
{ :15day, :5month },
{ :16day, :5month },
{ :19day, :5month },
{ :17day, :6month },
{ :18day, :6month },
{ :14day, :7month },
{ :16day, :7month },
{ :14day, :8month },
{ :15day, :8month },
{ :17day, :8month }
;
# Month can't have a unique day
my @filtered = @dates.g... | Give a code snippet in #Raku
Albert and Bernard just became friends with Cheryl, and they want to know when her birthday is.
Cheryl gave them a list of ten possible dates:
May 15, May 16, May 19
June 17, June 18
July 14, July 16
August 14, August 15, August 17
Cheryl then tells A... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rock-paper-scissors | Rock-paper-scissors | Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
The winner is decided by a set of rules:
... | #SuperCollider | SuperCollider | // play it in the REPL, evaluating line by line
a = RockPaperScissors.new;
a.next(Scissors);
a.next(Scissors);
a.next(Scissors);
a.next(Paper);
| Give a code snippet in #SuperCollider
Task
Implement the classic children's game Rock-paper-scissors, as well as a simple predictive AI (artificial intelligence) player.
Rock Paper Scissors is a two player game.
Each player chooses one of rock, paper or scissors, without knowing the other player's choice.
Th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Bulls_and_cows | Bulls and cows | Bulls and Cows
Task
Create a four digit random number from the digits 1 to 9, without duplication.
The program should:
ask for guesses to this number
reject guesses that are malformed
print the score for the guess
The score is computed as:
The player wins if the guess is the same as the random... | #MAXScript | MAXScript |
numCount = 4 -- number of digits to use
digits = #(1, 2, 3, 4, 5, 6, 7, 8, 9)
num = ""
while num.count < numCount and digits.count > 0 do
(
local r = random 1 digits.count
append num (digits[r] as string)
deleteitem digits r
)
digits = undefined
numGuesses = 0
inf = "Rules: \n1. Choose only % unique digits in an... | Give a code snippet in #MAXScript
Bulls and Cows
Task
Create a four digit random number from the digits 1 to 9, without duplication.
The program should:
ask for guesses to this number
reject guesses that are malformed
print the score for the guess
The score is computed as:
The player wins if ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_words_in_a_string | Reverse words in a string | Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spaces (formally, white-space); t... | #Scheme | Scheme |
(for-each
(lambda (s) (print (string-join (reverse (string-split s #/ +/)))))
(string-split
"---------- Ice and Fire ------------
fire, in end will world the say Some
ice. in say Some
desire of tasted I've what From
fire. favor who those with hold I
... elided paragraph last ...
... | Give a code snippet in #Scheme
Task
Reverse the order of all tokens in each of a number of strings and display the result; the order of characters within a token should not be modified.
Example
Hey you, Bub! would be shown reversed as: Bub! you, Hey
Tokens are any non-space characters separated by spa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Knuth_shuffle | Knuth shuffle | The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from 0 to last, the algorithm can be d... | #XPL0 | XPL0 | proc Shuffle(Array, Items, BytesPerItem);
int Array, Items, BytesPerItem;
int I, J;
char Temp(8);
[for I:= Items-1 downto 1 do
[J:= Ran(I+1); \range [0..I]
CopyMem(Temp, Array+I*BytesPerItem, BytesPerItem);
CopyMem(Array+I*BytesPerItem, Array+J*BytesPerItem, BytesPerItem);
CopyMem(Array+J*BytesPe... | Give a code snippet in #XPL0
The Knuth shuffle (a.k.a. the Fisher-Yates shuffle) is an algorithm for randomly shuffling the elements of an array.
Task
Implement the Knuth shuffle for an integer array (or, if possible, an array of any type).
Specification
Given an array items with indices ranging from 0 t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Angles_(geometric),_normalization_and_conversion | Angles (geometric), normalization and conversion | This task is about the normalization and/or conversion of (geometric) angles using
some common scales.
The angular scales that will be used in this task are:
degree
gradian
mil
radian
Definitions
The angular scales used or referenced here:
turn is a full turn or 360 degrees, also shown as 360º
... | #Raku | Raku |
my @units =
{ code => 'd', name => 'degrees' , number => 360 },
{ code => 'g', name => 'gradians', number => 400 },
{ code => 'm', name => 'mills' , number => 6400 },
{ code => 'r', name => 'radians' , number => tau },
;
my Code %cvt = (@units X @units).map: -> ($a, $b) {
"{$a.<code>}2{$b.<... | Give a code snippet in #Raku
This task is about the normalization and/or conversion of (geometric) angles using
some common scales.
The angular scales that will be used in this task are:
degree
gradian
mil
radian
Definitions
The angular scales used or referenced here:
turn is a full turn or 36... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Conway%27s_Game_of_Life | Conway's Game of Life | The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when dead, in an m-by-m (or m×m) sq... | #JavaScript | JavaScript | function GameOfLife () {
this.init = function (turns,width,height) {
this.board = new Array(height);
for (var x = 0; x < height; x++) {
this.board[x] = new Array(width);
for (var y = 0; y < width; y++) {
this.board[x][y] = Math.round(Math.random());
}
}
this.turns = turns;
}
this.nextGen = f... | Give a code snippet in #JavaScript
The Game of Life is a cellular automaton devised by the British mathematician John Horton Conway in 1970. It is the best-known example of a cellular automaton.
Conway's game of life is described here:
A cell C is represented by a 1 when alive, or 0 when de... | christopher/rosetta-code |
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