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
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http://rosettacode.org/wiki/Roots_of_a_quadratic_function | Roots of a quadratic function | This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your program must correctly handle n... | #Wren | Wren | import "/complex" for Complex
var quadratic = Fn.new { |a, b, c|
var d = b*b - 4*a*c
if (d == 0) {
// single root
return [[-b/(2*a)], null]
}
if (d > 0) {
// two real roots
var sr = d.sqrt
d = (b < 0) ? sr - b : -sr - b
return [[d/(2*a), 2*c/d], null]
... | Give a code snippet in #Wren
This task has been clarified. Its programming examples are in need of review to ensure that they still fit the requirements of the task.
Write a program to find the roots of a quadratic equation, i.e., solve the equation
a
x
2
+
b
x
+
c
=
0
{\displaystyle ax^{2}+bx+c=0}
.
Your p... | 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... | #Scala | Scala | println(new java.util.Date) | Give a code snippet in #Scala
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/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Yabasic | Yabasic | Give a code snippet in #Yabasic
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/Associative_array/Creation | Associative array/Creation | Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element ins... | #PicoLisp | PicoLisp | (put 'A 'foo 5)
(put 'A 'bar 10)
(put 'A 'baz 15)
(put 'A 'foo 20)
: (get 'A 'bar)
-> 10
: (get 'A 'foo)
-> 20
: (show 'A)
A NIL
foo 20
bar 10
baz 15 | Give a code snippet in #PicoLisp
Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Filter | Filter | Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| #Ruby | Ruby | # Enumerable#select returns a new array.
ary = [1, 2, 3, 4, 5, 6]
even_ary = ary.select {|elem| elem.even?}
p even_ary # => [2, 4, 6]
# Enumerable#select also works with Range.
range = 1..6
even_ary = range.select {|elem| elem.even?}
p even_ary # => [2, 4, 6] | Give a code snippet in #Ruby
Task
Select certain elements from an Array into a new Array in a generic way.
To demonstrate, select all even numbers from an Array.
As an option, give a second solution which filters destructively,
by modifying the original Array rather than creating a new Array.
| 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
≤... | #SQL | SQL | SELECT A+B | Give a code snippet in #SQL
A+B ─── a classic problem in programming contests, it's given so contestants can gain familiarity with the online judging system being used.
Task
Given two integers, A and B.
Their sum needs to be calculated.
Input data
Two integers are written in the input stream, separated ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ramanujan%27s_constant | Ramanujan's constant | Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| #Go | Go | package main
import (
"fmt"
"github.com/ALTree/bigfloat"
"math/big"
)
const (
prec = 256 // say
ps = "3.1415926535897932384626433832795028841971693993751058209749445923078164"
)
func q(d int64) *big.Float {
pi, _ := new(big.Float).SetPrec(prec).SetString(ps)
t := new(big.Float).SetPr... | Give a code snippet in #Go
Calculate Ramanujan's constant (as described on the OEIS site) with at least
32 digits of precision, by the method of your choice. Optionally, if using the 𝑒**(π*√x) approach,
show that when evaluated with the last four Heegner numbers
the result is almost an integer.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/File_extension_is_in_extensions_list | File extension is in extensions list | File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensions, tell whether the filename... | #PHP | PHP |
$allowed = ['zip', 'rar', '7z', 'gz', 'archive', 'A##', 'tar.bz2'];
$lc_allowed = array_map('strtolower', $allowed);
$tests = [
['MyData.a##',true],
['MyData.tar.Gz',true],
['MyData.gzip',false],
['MyData.7z.backup',false],
['MyData...',false],
['MyData',false],
['archive.tar.gz', true]
... | Give a code snippet in #PHP
File extension is in extensions list
You are encouraged to solve this task according to the task description, using any language you may know.
Filename extensions are a rudimentary but commonly used way of identifying files types.
Task
Given an arbitrary filename and a list of extensio... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Multiple_distinct_objects | Multiple distinct objects | Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they are considered unequal; etc. The code need ... | #jq | jq |
def Array(atype; n):
if atype == "number" then [ range(0;n) ]
elif atype == "object" then [ range(0;n)| {"value": . } ]
elif atype == "array" then [ range(0;n)| [.] ]
elif atype == "string" then [ range(0;n)| tostring ]
elif atype == "boolean" then
if n == 0 then [] elif n == 1 then [false] elif n==2... | Give a code snippet in #jq
Create a sequence (array, list, whatever) consisting of n distinct, initialized items of the same type. n should be determined at runtime.
By distinct we mean that if they are mutable, changes to one do not affect all others; if there is an appropriate equality operator they are considered ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Substring | Substring |
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 |... | #Maxima | Maxima | s: "the quick brown fox jumps over the lazy dog";
substring(s, 17);
/* "fox jumps over the lazy dog" */
substring(s, 17, 20);
/* "fox" */ | Give a code snippet in #Maxima
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_entire_file | Read entire file | Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished incrementally instead
(in which case... | #Blue | Blue | global _start
: syscall ( num:eax -- result:eax ) syscall ;
: exit ( status:edi -- noret ) 60 syscall ;
: bye ( -- noret ) 0 exit ;
: die ( err:eax -- noret ) neg exit ;
: unwrap ( result:eax -- value:eax ) dup 0 cmp ' die xl ;
: ordie ( result -- ) unwrap drop ;
: open ( pathname:edi flags:esi -- fd:eax ) 2 sy... | Give a code snippet in #Blue
Task
Load the entire contents of some text file as a single string variable.
If applicable, discuss: encoding selection, the possibility of memory-mapping.
Of course, in practice one should avoid reading an entire file at once
if the file is large and the task can be accomplished increm... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Subleq | Subleq | Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of signed integers. These integers... | #Logo | Logo | make "memory (array 32 0)
to load_subleq
local "i make "i 0
local "line
make "line readlist
while [or (not empty? :line) (not list? :line)] [
foreach :line [
setitem :i :memory ?
make "i sum :i 1
]
make "line readlist
]
end
to run_subleq
make "ip 0
while [greaterequal? :ip ... | Give a code snippet in #Logo
Subleq is an example of a One-Instruction Set Computer (OISC).
It is named after its only instruction, which is SUbtract and Branch if Less than or EQual to zero.
Task
Your task is to create an interpreter which emulates a SUBLEQ machine.
The machine's memory consists of an array of sig... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Compare_a_list_of_strings | Compare a list of strings | Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or false value, which could be used as t... | #Rust | Rust | fn strings_are_equal(seq: &[&str]) -> bool {
match seq {
&[] | &[_] => true,
&[x, y, ref tail @ ..] if x == y => strings_are_equal(&[&[y], tail].concat()),
_ => false
}
}
fn asc_strings(seq: &[&str]) -> bool {
match seq {
&[] | &[_] => true,
&[x, y, ref tail @ ..] i... | Give a code snippet in #Rust
Task
Given a list of arbitrarily many strings, show how to:
test if they are all lexically equal
test if every string is lexically less than the one after it (i.e. whether the list is in strict ascending order)
Each of those two tests should result in a single true or false v... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Old_Russian_measure_of_length | Old Russian measure of length | Task
Write a program to perform a conversion of the old Russian measures of length to the metric system (and vice versa).
It is an example of a linear transformation of several variables.
The program should accept a single value in a selected unit of measurement, and convert and return it to the other units:
... | #Julia | Julia | using DataStructures
const unit2mult = Dict(
"arshin" => 0.7112, "centimeter" => 0.01, "diuym" => 0.0254,
"fut" => 0.3048, "kilometer" => 1000.0, "liniya" => 0.00254,
"meter" => 1.0, "milia" => 7467.6, "piad" => 0.1778,
"sazhen" => 2.1336, "tochka" => 0.000254, "vershok"... | Give a code snippet in #Julia
Task
Write a program to perform a conversion of the old Russian measures of length to the metric system (and vice versa).
It is an example of a linear transformation of several variables.
The program should accept a single value in a selected unit of measurement, and convert and ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Break | Loops/Break | Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
If the number 10 is never gener... | #HolyC | HolyC | U16 a, b;
while (1) {
a = RandU16 % 20;
Print("%d\n", a);
if (a == 10) break;
b = RandU16 % 20;
Print("%d\n", b);
}
| Give a code snippet in #HolyC
Task
Show a loop which prints random numbers (each number newly generated each loop) from 0 to 19 (inclusive).
If a number is 10, stop the loop after printing it, and do not generate any further numbers.
Otherwise, generate and print a second random number before restarting the loop.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_two-dimensional_array_at_runtime | Create a two-dimensional array at runtime |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Get two integers from the user, then create a two-dimensional array where the two dimensions have the sizes given by those numbers, and which can be accessed ... | #BASIC | BASIC | 10 INPUT "ENTER TWO INTEGERS:"; X%, Y%
20 DIM A%(X% - 1, Y% - 1)
30 X% = RND(1) * X%
40 Y% = RND(1) * Y%
50 A%(X%, Y%) = -32767
60 PRINT A%(X%, Y%)
70 CLEAR | Give a code snippet in #BASIC
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
Get two integers from the user, then create a two-dimensional array where the two dimensions have the sizes given by those numb... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Order_two_numerical_lists | Order two numerical lists | sorting
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
She... | #Klingphix | Klingphix | include ..\Utilitys.tlhy
( 1 2 3 ) ( 1 2 3 4 ) less ?
( 1 2 3 4 ) ( 1 2 3 ) less ?
( 1 2 4 ) ( 1 2 3 ) less ?
( 1 2 3 ) ( 1 2 3 ) less ?
( 1 2 3 ) ( 1 2 4 ) less ?
"End " input | Give a code snippet in #Klingphix
sorting
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sor... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Benford%27s_law | Benford's law |
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the first-digit law, refers to the freque... | #Common_Lisp | Common Lisp | (defun calculate-distribution (numbers)
"Return the frequency distribution of the most significant nonzero
digits in the given list of numbers. The first element of the list
is the frequency for digit 1, the second for digit 2, and so on."
(defun nonzero-digit-p (c)
"Check whether the character is a n... | Give a code snippet in #Common_Lisp
This page uses content from Wikipedia. The original article was at Benford's_law. 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)
Benford's law, also called the ... | 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
... | #ALGOL_68 | ALGOL 68 | MODE DATA = REF CHAR;
PROC in place insertion sort = (REF[]DATA item)VOID:
BEGIN
INT first := LWB item;
INT last := UPB item;
INT j;
DATA value;
FOR i FROM first + 1 TO last DO
value := item[i];
j := i - 1;
# WHILE j >= LWB item AND j <= UPB item ANDF item[j] > value DO // example of A... | Give a code snippet in #ALGOL_68
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/For | Loops/For | “For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract structures other than the integers.
... | #Haskell | Haskell | import Control.Monad
main = do
forM_ [1..5] $ \i -> do
forM_ [1..i] $ \j -> do
putChar '*'
putChar '\n' | Give a code snippet in #Haskell
“For” loops are used to make some block of code be iterated a number of times, setting a variable or parameter to a monotonically increasing integer value for each execution of the block of code.
Common extensions of this allow other counting patterns or iterating over abstract struc... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Josephus_problem | Josephus problem | Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting from prisoner
0
{\displaystyle 0}
,
removing eve... | #ALGOL_68 | ALGOL 68 | BEGIN
PROC josephus = (INT n, k, m) INT :
CO Return m-th on the reversed kill list; m=0 is final survivor. CO
BEGIN
INT lm := m; CO Local copy of m CO
FOR a FROM m+1 WHILE a <= n DO lm := (lm+k) %* a OD;
lm
END;
INT n = 41, k=3;
printf (($"n = ", g(0), ", k = ", g(0), ", final surv... | Give a code snippet in #ALGOL_68
Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting from prisoner
0
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stem-and-leaf_plot | Stem-and-leaf plot | Create a well-formatted stem-and-leaf plot from the following data set, where the leaves are the last digits:
12 127 28 42 39 113 42 18 44 118 44 37 113 124 37 48 127 36 29 31 125 139 131 115 105 132 104 123 35 113 122 42 117 119 58 109 23 105 63 27 44 105 99 41 128 121 116 125 32 61 37 127 29 113 121 58 114 126 53 11... | #PureBasic | PureBasic | If OpenConsole()
Dim MyList(120)
Define i, j, StemMax, StemMin
Restore MyData ; Get the address of MyData, e.g. the data to print as a Stem-and-leaf plot
For a=0 To 120
Read.i MyList(a) ; Read the data into the used Array
If MyList(a)>StemMax
StemMax=MyList(a) ; Find the largest St... | Give a code snippet in #PureBasic
Create a well-formatted stem-and-leaf plot from the following data set, where the leaves are the last digits:
12 127 28 42 39 113 42 18 44 118 44 37 113 124 37 48 127 36 29 31 125 139 131 115 105 132 104 123 35 113 122 42 117 119 58 109 23 105 63 27 44 105 99 41 128 121 116 125 32 61... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Check_input_device_is_a_terminal | Check input device is a terminal | Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| #FreeBASIC | FreeBASIC |
Open Cons For Input As #1
' Open Cons abre los flujos de entrada (stdin) o salida (stdout) estándar
' de la consola para leer o escribir.
If Err Then
Print "Input doesn't come from tt."
Else
Print "Input comes from tty."
End If
Close #1
Sleep
| Give a code snippet in #FreeBASIC
Task
Demonstrate how to check whether the input device is a terminal or not.
Related task
Check output device is a terminal
| christopher/rosetta-code | |
http://rosettacode.org/wiki/I_before_E_except_after_C | I before E except after C | The phrase "I before E, except after C" is a
widely known mnemonic which is supposed to help when spelling English words.
Task
Using the word list from http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
check if the two sub-clauses of the phrase are plausible individually:
"I before E when not pre... | #Wren | Wren | import "io" for File
import "/pattern" for Pattern
import "/fmt" for Fmt
var yesNo = Fn.new { |b| (b) ? "yes" : "no" }
var plausRatio = 2
var count1 = 0 // [^c]ie
var count2 = 0 // [^c]ei
var count3 = 0 // cie
var count4 = 0 // cei
var count5 = 0 // ^ie
var count6 = 0 // ^ei
var p1 = Pattern.new("^cie")
v... | Give a code snippet in #Wren
The phrase "I before E, except after C" is a
widely known mnemonic which is supposed to help when spelling English words.
Task
Using the word list from http://wiki.puzzlers.org/pub/wordlists/unixdict.txt,
check if the two sub-clauses of the phrase are plausible individually... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Rosetta_Code/Find_bare_lang_tags | Rosetta Code/Find bare lang tags | Task
Find all <lang> tags without a language specified in the text of a page.
Display counts by language section:
Description
<lang>Pseudocode</lang>
=={{header|C}}==
<lang C>printf("Hello world!\n");</lang>
=={{header|Perl}}==
<lang>print "Hello world!\n"</lang>
should display something like
2 bare langu... | #Groovy | Groovy | import java.util.function.Predicate
import java.util.regex.Matcher
import java.util.regex.Pattern
class FindBareTags {
private static final Pattern TITLE_PATTERN = Pattern.compile("\"title\": \"([^\"]+)\"")
private static final Pattern HEADER_PATTERN = Pattern.compile("==\\{\\{header\\|([^}]+)}}==")
priva... | Give a code snippet in #Groovy
Task
Find all <lang> tags without a language specified in the text of a page.
Display counts by language section:
Description
<lang>Pseudocode</lang>
=={{header|C}}==
<lang C>printf("Hello world!\n");</lang>
=={{header|Perl}}==
<lang>print "Hello world!\n"</lang>
should disp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dinesman%27s_multiple-dwelling_problem | Dinesman's multiple-dwelling problem | Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allowed. Flexibility and ease of... | #J | J | possible=: ((i.!5) A. i.5) { 'BCFMS' | Give a code snippet in #J
Task
Solve Dinesman's multiple dwelling problem but in a way that most naturally follows the problem statement given below.
Solutions are allowed (but not required) to parse and interpret the problem text, but should remain flexible and should state what changes to the problem text are allow... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Execute_SNUSP | Execute SNUSP | Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&') are also allowed, but not... | #J | J |
Note 'snusp'
Without $ character the program counter starts at top left (0 0) moving to the right (0 1)
> increment the pointer (to point to the next cell to the right).
< decrement the pointer (to point to the next cell to the left).
+ increment (increase by one) the cell at the... | Give a code snippet in #J
Execute SNUSP is an implementation of SNUSP.
Other implementations of SNUSP.
RCSNUSP
SNUSP
An implementation need only properly implement the Core SNUSP instructions ('$', '\', '/', '+', '-', '<', '>', ',', '.', '!', and '?'). Modular SNUSP ('#', '@') and Bloated SNUSP (':', ';', '%', and '&'... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/With_multiple_ranges | Loops/With multiple ranges | Loops/With multiple ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages allow multiple loop ranges, such as the PL/I example (snippet) below.
/* all variables are DECLARED as integers. */
prod=... | #Picat | Picat | foreach(I in 1..3, J in 4..6, K in 7..9)
% ...
end | Give a code snippet in #Picat
Loops/With multiple ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages allow multiple loop ranges, such as the PL/I example (snippet) below.
/* all variables are DECLARED ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Dynamic_variable_names | Dynamic variable names | Task
Create a variable with a user-defined name.
The variable name should not be written in the program text, but should be taken from the user dynamically.
See also
Eval in environment is a similar task.
| #Phix | Phix | constant globals = new_dict()
while 1 do
string name = prompt_string("Enter name or press Enter to quit:")
if length(name)=0 then exit end if
bool bExists = (getd_index(name,globals)!=NULL)
string prompt = iff(not bExists?"No such name, enter a value:"
:sprintf("Already exists, new ... | Give a code snippet in #Phix
Task
Create a variable with a user-defined name.
The variable name should not be written in the program text, but should be taken from the user dynamically.
See also
Eval in environment is a similar task.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fork | Fork | Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| #XPL0 | XPL0 | int Key, Process;
[Key:= SharedMem(4); \allocate 4 bytes of memory common to both processes
Process:= Fork(1); \start one child process
case Process of
0: [Lock(Key); Text(0, "Rosetta"); CrLf(0); Unlock(Key)]; \parent process
1: [Lock(Key); Text(0, "Code"); CrLf(0); Unlock(Key)] \child process
o... | Give a code snippet in #XPL0
Task
Spawn a new process which can run simultaneously with, and independently of, the original parent process.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/HTTPS | HTTPS | Task
Send a GET request to obtain the resource located at the URL "https://www.w3.org/", then print it to the console.
Checking the host certificate for validity is recommended.
Do not authenticate. That is the subject of other tasks.
Readers may wish to contrast with the HTTP Request task, and also the task on HTT... | #Ring | Ring |
cStr= download("http://sourceforge.net/")
see cStr + nl
| Give a code snippet in #Ring
Task
Send a GET request to obtain the resource located at the URL "https://www.w3.org/", then print it to the console.
Checking the host certificate for validity is recommended.
Do not authenticate. That is the subject of other tasks.
Readers may wish to contrast with the HTTP Request ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Combinations_and_permutations | Combinations and permutations |
This page uses content from Wikipedia. The original article was at Combination. 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)
This page uses content from Wikipedia. The original article was at P... | #Raku | Raku | multi P($n, $k) { [*] $n - $k + 1 .. $n }
multi C($n, $k) { P($n, $k) / [*] 1 .. $k }
sub lstirling(\n) {
n < 10 ?? lstirling(n+1) - log(n+1) !!
.5*log(2*pi*n)+ n*log(n/e+1/(12*e*n))
}
role Logarithm {
method gist {
my $e = (self/10.log).Int;
sprintf "%.8fE%+d", exp(self - $e*10.log), $e;
}
}
mult... | Give a code snippet in #Raku
This page uses content from Wikipedia. The original article was at Combination. 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)
This page uses content from Wikipedia.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Comma_quibbling | Comma quibbling | Comma quibbling is a task originally set by Eric Lippert in his blog.
Task
Write a function to generate a string output which is the concatenation of input words from a list/sequence where:
An input of no words produces the output string of just the two brace characters "{}".
An input of just one word, e.g. ["AB... | #SenseTalk | SenseTalk | Quibble [] // (No input words).
Quibble ["ABC"]
Quibble ["ABC", "DEF"]
Quibble ["ABC", "DEF", "G", "H"]
to Quibble with wordList
if the number of items in wordList is ...
... 0 then put "{}"
... 1 then put "{" & item 1 of wordList & "}"
... else put "{" & (items first to penultimate of wordList) joined by ", "... | Give a code snippet in #SenseTalk
Comma quibbling is a task originally set by Eric Lippert in his blog.
Task
Write a function to generate a string output which is the concatenation of input words from a list/sequence where:
An input of no words produces the output string of just the two brace characters "{}".
A... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Infinite | Loops/Infinite | Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within l... | #TI-83_BASIC | TI-83 BASIC |
:Lbl 1
:Disp "SPAM
:Goto 1
| Give a code snippet in #TI-83_BASIC
Task
Print out SPAM followed by a newline in an infinite loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #J | J | nl__example 0 | Give a code snippet in #J
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compoun... | 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.
| #Ruby | Ruby | class Pixmap
# 'open' is a class method
def self.open(filename)
bitmap = nil
File.open(filename, 'r') do |f|
header = [f.gets.chomp, f.gets.chomp, f.gets.chomp]
width, height = header[1].split.map {|n| n.to_i }
if header[0] != 'P6' or header[2] != '255' or width < 1 or height < 1
r... | Give a code snippet in #Ruby
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 graysca... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sum_digits_of_an_integer | Sum digits of an integer | Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| #BCPL | BCPL | get "libhdr"
let digitsum(n, base) =
n=0 -> 0,
n rem base + digitsum(n/base, base)
let start() be
$( writef("%N*N", digitsum(1, 10)) // prints 1
writef("%N*N", digitsum(1234, 10)) // prints 10
writef("%N*N", digitsum(#1234, 8)) // also prints 10
writef("%N*N", digitsum(#XFE, 16)) //... | Give a code snippet in #BCPL
Task
Take a Natural Number in a given base and return the sum of its digits:
110 sums to 1
123410 sums to 10
fe16 sums to 29
f0e16 sums to 29
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Comments | Comments | Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| #Unlambda | Unlambda | # this is a comment.
| Give a code snippet in #Unlambda
Task
Show all ways to include text in a language source file
that's completely ignored by the compiler or interpreter.
Related tasks
Documentation
Here_document
See also
Wikipedia
xkcd (Humor: hand gesture denoting // for "commenting out" people.)
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Functional_coverage_tree | Functional coverage tree | Functional coverage is a measure of how much a particular function of a system
has been verified as correct. It is used heavily in tracking the completeness
of the verification of complex System on Chip (SoC) integrated circuits, where
it can also be used to track how well the functional requirements of the
system have... | #Lua | Lua | -- DATA:
local function node(name, weight, coverage, children)
return { name=name, weight=weight or 1.0, coverage=coverage or 0.0, sumofweights=0, delta=0, children=children }
end
local root =
node("cleaning", nil, nil, {
node("house1", 40, nil, {
node("bedrooms", nil, 0.25),
node("bathrooms", nil, nil, {... | Give a code snippet in #Lua
Functional coverage is a measure of how much a particular function of a system
has been verified as correct. It is used heavily in tracking the completeness
of the verification of complex System on Chip (SoC) integrated circuits, where
it can also be used to track how well the functional re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Infinity | Infinity | Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Otherwise, return the largest possible po... | #MiniScript | MiniScript | posInfinity = 1/0
print posInfinity | Give a code snippet in #MiniScript
Task
Write a function which tests if infinity is supported for floating point numbers (this step should be omitted for languages where the language specification already demands the existence of infinity, e.g. by demanding IEEE numbers), and if so, returns positive infinity. Other... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extreme_floating_point_values | Extreme floating point values | The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to calculate these, (and maybe ... | #C | C | #include <stdio.h>
int main()
{
double inf = 1/0.0;
double minus_inf = -1/0.0;
double minus_zero = -1/ inf ;
double nan = 0.0/0.0;
printf("positive infinity: %f\n",inf);
printf("negative infinity: %f\n",minus_inf);
printf("negative zero: %f\n",minus_zero);
printf("not a number: %f\n"... | Give a code snippet in #C
The IEEE floating point specification defines certain 'extreme' floating point values such as minus zero, -0.0, a value distinct from plus zero; not a number, NaN; and plus and minus infinity.
The task is to use expressions involving other 'normal' floating point values in your language to c... | 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... | #Maxima | Maxima | data: apply(matrix, makelist(makelist(random(100), 20), 20))$
find_value(a, x) := block(
[p, q],
[p, q]: matrix_size(a),
catch(
for i thru p do
for j thru q do
if a[i, j] = x then throw([i, j]),
'not\ found
)
)$
find_value(data, 100);
not found | Give a code snippet in #Maxima
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/Narcissist | Narcissist | Quoting from the Esolangs wiki page:
A narcissist (or Narcissus program) is the decision-problem version of a quine.
A quine, when run, takes no input, but produces a copy of its own source code at its output. In contrast, a narcissist reads a string of symbols from its input, and produces no output except a "1" o... | #Ada | Ada | with Ada.Text_IO;procedure Self is Q:Character:='"';A:String:="with Ada.Text_IO;procedure Self is Q:Character:='';A:String:=;B:String:=A(1..49)&Q&A(50..61)&Q&A&Q&A(62..A'Last);C:String:=Ada.Text_IO.Get_Line;begin Ada.Text_IO.Put_Line(Boolean'Image(B=C));end Self;";B:String:=A(1..49)&Q&A(50..61)&Q&A&Q&A(62..A'Last);C:St... | Give a code snippet in #Ada
Quoting from the Esolangs wiki page:
A narcissist (or Narcissus program) is the decision-problem version of a quine.
A quine, when run, takes no input, but produces a copy of its own source code at its output. In contrast, a narcissist reads a string of symbols from its input, and prod... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Extend_your_language | Extend your language | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g. by using macros), other langua... | #Idris | Idris | if2 : Bool -> Bool -> Lazy a -> Lazy a -> Lazy a -> Lazy a -> a
if2 True True v _ _ _ = v
if2 True False _ v _ _ = v
if2 False True _ _ v _ = v
if2 _ _ _ _ _ v = v | Give a code snippet in #Idris
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Some programming languages allow you to extend the language. While this can be done to a certain degree in most languages (e.g.... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ethiopian_multiplication | Ethiopian multiplication | Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and write the result below the last ... | #Scala | Scala |
def ethiopian(i:Int, j:Int):Int=
pairIterator(i,j).filter(x=> !isEven(x._1)).map(x=>x._2).foldLeft(0){(x,y)=>x+y}
def ethiopian2(i:Int, j:Int):Int=
pairIterator(i,j).map(x=>if(isEven(x._1)) 0 else x._2).foldLeft(0){(x,y)=>x+y}
def ethiopian3(i:Int, j:Int):Int=
{
var res=0;
for((h,d) <- pairIterator(i,... | Give a code snippet in #Scala
Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.
Method:
Take two numbers to be multiplied and write them down at the top of two columns.
In the left-hand column repeatedly halve the last number, discarding any remainders, and w... | 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... | #AWK | AWK | # usage: awk -f rot13.awk
BEGIN {
for(i=0; i < 256; i++) {
amap[sprintf("%c", i)] = i
}
for(l=amap["a"]; l <= amap["z"]; l++) {
rot13[l] = sprintf("%c", (((l-amap["a"])+13) % 26 ) + amap["a"])
}
FS = ""
}
{
o = ""
for(i=1; i <= NF; i++) {
if ( amap[tolower($i)] in rot13 ) {
c = rot13[am... | Give a code snippet in #AWK
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/Conditional_structures | Conditional structures | Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common conditional structures include ... | #Ruby | Ruby | ' Boolean Evaluations
'
' > Greater Than
' < Less Than
' >= Greater Than Or Equal To
' <= Less Than Or Equal To
' = Equal to
x = 0
if x = 0 then print "Zero"
' --------------------------
' if/then/else
if x = 0 then
print "Zero"
else
print "Nonzero"
end if
' --------------------------
' not
if x then
print "x h... | Give a code snippet in #Ruby
Control Structures
These are examples of control structures. You may also be interested in:
Conditional structures
Exceptions
Flow-control structures
Loops
Task
List the conditional structures offered by a programming language. See Wikipedia: conditionals for descriptions.
Common c... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Holidays_related_to_Easter | Holidays related to Easter | Task
Calculate the dates of:
Easter
Ascension Thursday
Pentecost
Trinity Sunday
Corpus Christi feast (for Catholic)
All Saints' Sunday (for Orthodox)
As an example, calculate for the first year of each century from;
years 400 to 2100 CE and for
years 2010 to 2020 CE.
Note
... | #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | Needs["Calendar`"];DateFormat[x_]:=DateString[x,{"DayNameShort"," ","DayShort"," ","MonthName"}]
Map[StringJoin[ToString[#]," Easter: ",DateFormat[EasterSunday[#]],
", Ascension: ",DateFormat[DaysPlus[EasterSunday[#],39]],
", Pentecost: ",DateFormat[DaysPlus[EasterSunday[#],49]],
", Trinity: ",DateFormat[DaysPlus[Easte... | Give a code snippet in #Mathematica.2FWolfram_Language
Task
Calculate the dates of:
Easter
Ascension Thursday
Pentecost
Trinity Sunday
Corpus Christi feast (for Catholic)
All Saints' Sunday (for Orthodox)
As an example, calculate for the first year of each century from;
years 400 to 2... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Web_server | Hello world/Web server | The browser is the new GUI !
Task
Serve our standard text Goodbye, World! to http://localhost:8080/ so that it can be viewed with a web browser.
The provided solution must start or implement a server that accepts multiple client connections and serves text as requested.
Note that starting a web browser or... | #Io | Io |
WebRequest := Object clone do(
handleSocket := method(aSocket,
aSocket streamWrite("Goodbye, World!")
aSocket close
)
)
WebServer := Server clone do(
setPort(8080)
handleSocket := method(aSocket,
WebRequest clone asyncSend(handleSocket(aSocket))
)
)
WebServer start
| Give a code snippet in #Io
The browser is the new GUI !
Task
Serve our standard text Goodbye, World! to http://localhost:8080/ so that it can be viewed with a web browser.
The provided solution must start or implement a server that accepts multiple client connections and serves text as requested.
Note th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Array_concatenation | Array concatenation | Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| #F.23 | F# | let a = [|1; 2; 3|]
let b = [|4; 5; 6;|]
let c = Array.append a b | Give a code snippet in #F.23
Task
Show how to concatenate two arrays in your language.
If this is as simple as array1 + array2, so be it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/GUI_component_interaction | GUI component interaction |
Almost every application needs to communicate with the user in some way.
Therefore, a substantial part of the code deals with the interaction
of program logic with GUI components.
Typically, the following is needed:
put values into input fields under program control
read and check input from the user
pop up dial... | #Go | Go | package main
import (
"github.com/gotk3/gotk3/gtk"
"log"
"math/rand"
"strconv"
"time"
)
func validateInput(window *gtk.Window, str string) (int64, bool) {
i, err := strconv.ParseInt(str, 10, 64)
if err != nil {
dialog := gtk.MessageDialogNew(
window,
gtk.D... | Give a code snippet in #Go
Almost every application needs to communicate with the user in some way.
Therefore, a substantial part of the code deals with the interaction
of program logic with GUI components.
Typically, the following is needed:
put values into input fields under program control
read and check inpu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Integer_comparison | Integer comparison |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #Rust | Rust | use std::io::{self, BufRead};
fn main() {
let mut reader = io::stdin();
let mut buffer = String::new();
let mut lines = reader.lock().lines().take(2);
let nums: Vec<i32>= lines.map(|string|
string.unwrap().trim().parse().unwrap()
).collect();
let a: i32 = nums[0];
let b: i32 = ... | Give a code snippet in #Rust
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #LOLCODE | LOLCODE | HAI 1.2
CAN HAS STDIO?
HOW IZ I Eratosumthin YR Max
I HAS A Siv ITZ A BUKKIT
Siv HAS A SRS 1 ITZ 0
I HAS A Index ITZ 2
IM IN YR Inishul UPPIN YR Dummy WILE DIFFRINT Index AN SUM OF Max AN 1
Siv HAS A SRS Index ITZ 1
Index R SUM OF Index AN 1
IM OUTTA YR Inishul
I HAS A Prime ITZ 2
IM IN YR Mai... | Give a code snippet in #LOLCODE
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Abbreviations,_simple | Abbreviations, simple | The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3 backup 2 bottom 1 Cappend 2 change 1 ... | #JavaScript | JavaScript | (() => {
'use strict';
// withExpansions :: [(String, Int)] -> String -> String
const withExpansions = tbl => s =>
unwords(map(expanded(tbl), words(s)));
// expanded :: [(String, Int)] -> String -> String
const expanded = tbl => s => {
const
lng = s.length,
... | Give a code snippet in #JavaScript
The use of abbreviations (also sometimes called synonyms, nicknames, AKAs, or aliases) can be an
easy way to add flexibility when specifying or using commands, sub─commands, options, etc.
For this task, the following command table will be used:
add 1 alter 3 backu... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Downward_for | Loops/Downward for | Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increment loop index within loop body... | #Wart | Wart | for i 10 (i >= 0) --i
prn i | Give a code snippet in #Wart
Task
Write a for loop which writes a countdown from 10 to 0.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For with a specified step
Loops/Foreach
Loops/Increme... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Comma_quibbling | Comma quibbling | Comma quibbling is a task originally set by Eric Lippert in his blog.
Task
Write a function to generate a string output which is the concatenation of input words from a list/sequence where:
An input of no words produces the output string of just the two brace characters "{}".
An input of just one word, e.g. ["AB... | #JavaScript | JavaScript | function quibble(words) {
return "{" +
words.slice(0, words.length-1).join(",") +
(words.length > 1 ? " and " : "") +
(words[words.length-1] || '') +
"}";
}
[[], ["ABC"], ["ABC", "DEF"], ["ABC", "DEF", "G", "H"]].forEach(
function(s) {
console.log(quibble(s));
}
); | Give a code snippet in #JavaScript
Comma quibbling is a task originally set by Eric Lippert in his blog.
Task
Write a function to generate a string output which is the concatenation of input words from a list/sequence where:
An input of no words produces the output string of just the two brace characters "{}".
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Digital_root/Multiplicative_digital_root | Digital root/Multiplicative digital root | The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\displaystyle i}
to
0
... | #J | J | 10&#.inv 123321
1 2 3 3 2 1 | Give a code snippet in #J
The multiplicative digital root (MDR) and multiplicative persistence (MP) of a number,
n
{\displaystyle n}
, is calculated rather like the Digital root except digits are multiplied instead of being added:
Set
m
{\displaystyle m}
to
n
{\displaystyle n}
and
i
{\di... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pernicious_numbers | Pernicious numbers | A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is prime, and therefore
22 is a pe... | #zkl | zkl | primes:=T(2,3,5,7,11,13,17,19,23,29,31,37,41);
N:=0; foreach n in ([2..]){
if(n.num1s : primes.holds(_)){
print(n," ");
if((N+=1)==25) break;
}
}
foreach n in ([0d888888877..888888888]){
if (n.num1s : primes.holds(_)) "%,d; ".fmt(n).print();
} | Give a code snippet in #zkl
A pernicious number is a positive integer whose population count is a prime.
The population count is the number of ones in the binary representation of a non-negative integer.
Example
22 (which is 10110 in binary) has a population count of 3, which is prime, ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/100_doors | 100 doors | There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...), and toggle it.
The third... | #Onyx | Onyx | $Door dict def
1 1 100 {Door exch false put} for
$Toggle {dup Door exch get not Door up put} def
$EveryNthDoor {dup 100 {Toggle} for} def
$Run {1 1 100 {EveryNthDoor} for} def
$ShowDoor {dup `Door no. ' exch cvs cat ` is ' cat
exch Door exch get {`open.\n'}{`shut.\n'} ifelse cat
print flush} def
Run 1 1 100 {ShowDo... | Give a code snippet in #Onyx
There are 100 doors in a row that are all initially closed.
You make 100 passes by the doors.
The first time through, visit every door and toggle the door (if the door is closed, open it; if it is open, close it).
The second time, only visit every 2nd door (door #2, #4, #6, ...... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Mayan_numerals | Mayan numerals | Task
Present numbers using the Mayan numbering system (displaying the Mayan numerals in a cartouche).
Mayan numbers
Normally, Mayan numbers are written vertically (top─to─bottom) with the most significant
numeral at the top (in the sense that decimal numbers are written left─to─right with the most signific... | #Factor | Factor | USING: arrays formatting io kernel make math math.extras
sequences ;
IN: rosetta-code.mayan-numerals
: mayan-digit ( n -- m pair ) 20 /mod 5 /mod swap 2array ;
: integer>mayan ( n -- seq )
[ [ mayan-digit , ] until-zero ] { } make reverse ;
: ones ( n -- str ) [ CHAR: ● ] "" replicate-as ;
: fives ( n -- str ... | Give a code snippet in #Factor
Task
Present numbers using the Mayan numbering system (displaying the Mayan numerals in a cartouche).
Mayan numbers
Normally, Mayan numbers are written vertically (top─to─bottom) with the most significant
numeral at the top (in the sense that decimal numbers are written left... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Reverse_a_string | Reverse a string | Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
... | #Groovy | Groovy | println "Able was I, 'ere I saw Elba.".reverse() | Give a code snippet in #Groovy
Task
Take a string and reverse it.
For example, "asdf" becomes "fdsa".
Extra credit
Preserve Unicode combining characters.
For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empt... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Create_a_file_on_magnetic_tape | Create a file on magnetic tape | The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| #COBOL | COBOL | >>SOURCE FORMAT IS FREE
IDENTIFICATION DIVISION.
PROGRAM-ID. MAKE-TAPE-FILE.
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
SELECT TAPE-FILE
ASSIGN "./TAPE.FILE"
ORGANIZATION IS LINE SEQUENTIAL.
DATA DIVISION.
FILE SECTION.
FD TAPE-FILE.
01 TAPE-FILE-RECORD PIC X(51).
PROCEDU... | Give a code snippet in #COBOL
The task is to create a new file called "TAPE.FILE" of any size on Magnetic Tape.
| 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:
*
* *
* *
* * * *
* *
* * * *
... | #8080_Assembly | 8080 Assembly | argmt: equ 5Dh ; Command line argument
puts: equ 9 ; CP/M syscall to print a string
putch: equ 2 ; CP/M syscall to print a character
org 100h
mvi b,4 ; Default order is 4
mvi e,' ' ; Keep space in E since we're saving it anyway
lda argmt ; Argument given?
cmp e ; If not, use default
jz start
sui '0' ; Make sure ... | Give a code snippet in #8080_Assembly
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/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).
| #Gosu | Gosu |
gw.lang.reflect.json.Json#fromJson( String json ) : javax.script.Bindings
| Give a code snippet in #Gosu
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/Pythagorean_quadruples | Pythagorean quadruples |
One form of Pythagorean quadruples is (for positive integers a, b, c, and d):
a2 + b2 + c2 = d2
An example:
22 + 32 + 62 = 72
which is:
4 + 9 + 36 = 49
Task
For positive integers up 2,200 (inclusive), for all values of ... | #PicoLisp | PicoLisp | (de quadruples (N)
(let (AB NIL S 3 R)
(for A N
(for (B A (>= N B) (inc B))
(idx
'AB
(+ (* A A) (* B B))
T ) ) )
(for C N
(let (S1 S S2)
(inc 'S 2)
(setq S2 S)
(for (D (+ C 1) (>= N D) (inc D... | Give a code snippet in #PicoLisp
One form of Pythagorean quadruples is (for positive integers a, b, c, and d):
a2 + b2 + c2 = d2
An example:
22 + 32 + 62 = 72
which is:
4 + 9 + 36 = 49
Task
For positive integers up 2,200 (... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Legendre_prime_counting_function | Legendre prime counting function | The prime-counting function π(n) computes the number of primes not greater than n. Legendre was the first mathematician to create a formula to compute π(n) based on the inclusion/exclusion principle.
To calculate:
Define
φ(x, 0) = x
φ(x, a) = φ(x, a−1) − φ(⌊x/pa⌋, a−1), where pa is the ath prime number.
then
π(n) ... | #jq | jq | # For the sake of the accuracy of integer arithmetic when using gojq:
def power($b): . as $in | reduce range(0;$b) as $i (1; . * $in);
# Input: $n, which is assumed to be positive integer,
# Output: an array of primes less than or equal to $n (e.g. 10|eratosthenes #=> [2,3,5,7]
def eratosthenes:
# erase(i) sets .[i... | Give a code snippet in #jq
The prime-counting function π(n) computes the number of primes not greater than n. Legendre was the first mathematician to create a formula to compute π(n) based on the inclusion/exclusion principle.
To calculate:
Define
φ(x, 0) = x
φ(x, a) = φ(x, a−1) − φ(⌊x/pa⌋, a−1), where pa is the at... | christopher/rosetta-code | |
http://rosettacode.org/wiki/System_time | System time | Task
Output the system time (any units will do as long as they are noted) either by a system command or one built into the language.
The system time can be used for debugging, network information, random number seeds, or something as simple as program performance.
Related task
Date format
See also
Retr... | #CLU | CLU | start_up = proc ()
stream$putl(stream$primary_output(), date$unparse(now()))
end start_up | Give a code snippet in #CLU
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
Da... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Merge_sort | Sorting algorithms/Merge sort |
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick sort
O(n log2n) sorts
Shell Sort
... | #Clojure | Clojure |
(defn merge [left right]
(cond (nil? left) right
(nil? right) left
:else (let [[l & *left] left
[r & *right] right]
(if (<= l r) (cons l (merge *left right))
(cons r (merge left *right))))))
(defn merge-sort [list]
(if (< (count li... | Give a code snippet in #Clojure
Sorting Algorithm
This is a sorting algorithm. It may be applied to a set of data in order to sort it.
For comparing various sorts, see compare sorts.
For other sorting algorithms, see sorting algorithms, or:
O(n logn) sorts
Heap sort |
Merge sort |
Patience sort |
Quick ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Perfect_totient_numbers | Perfect totient numbers | Generate and show here, the first twenty Perfect totient numbers.
Related task
Totient function
Also see
the OEIS entry for perfect totient numbers.
mrob list of the first 54
| #Quackery | Quackery | [ 0 over
[ dup 1 != while
totient
dup dip +
again ]
drop = ] is perfecttotient ( n --> b )
[ [] 1
[ dup perfecttotient if
[ dup dip join ]
2 +
over size 20 =
until ] drop ] is task ( --> )
| Give a code snippet in #Quackery
Generate and show here, the first twenty Perfect totient numbers.
Related task
Totient function
Also see
the OEIS entry for perfect totient numbers.
mrob list of the first 54
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Accumulator_factory | Accumulator factory | A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric values passed in so far to that accumulat... | #PostScript | PostScript | /mk-acc { % accumulator generator
{0 add 0 0 2 index put}
7 array copy
dup 0 4 -1 roll put
dup dup 2 exch put
cvx
} def
% Examples (= is a printing command in PostScript):
/a 1 mk-acc def % create accumulator #1, name it a
5 a = % add 5 to 1, print it
10 mk-acc ... | Give a code snippet in #PostScript
A problem posed by Paul Graham is that of creating a function that takes a single (numeric) argument and which returns another function that is an accumulator. The returned accumulator function in turn also takes a single numeric argument, and returns the sum of all the numeric value... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Wrong_ranges | Loops/Wrong ranges | Loops/Wrong ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages have syntax or function(s) to generate a range of numeric values from a start value, a stop value, and an increment.
The purpose of this task is to select the range syntax/functi... | #Raku | Raku | # Given sequence definitions
# start stop inc. Comment
for -2, 2, 1, # Normal
-2, 2, 0, # Zero increment
-2, 2, -1, # Increments away from stop value
-2, 2, 10, # First increment is beyond stop value
2, -2, 1, # Start more than stop: positive increment
... | Give a code snippet in #Raku
Loops/Wrong ranges
You are encouraged to solve this task according to the task description, using any language you may know.
Some languages have syntax or function(s) to generate a range of numeric values from a start value, a stop value, and an increment.
The purpose of this task is to ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Zoea_Visual | Zoea Visual | Give a code snippet in #Zoea_Visual
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | ||
http://rosettacode.org/wiki/21_game | 21 game | 21 game
You are encouraged to solve this task according to the task description, using any language you may know.
21 is a two player game, the game is played by choosing
a number (1, 2, or 3) to be added to the running total.
The game is won by the player whose chosen number causes the running total
to reach exactly ... | #Haskell | Haskell | import System.Random
import System.IO
import System.Exit
import Control.Monad
import Text.Read
import Data.Maybe
promptAgain :: IO Int
promptAgain = do
putStrLn "Invalid input - must be a number among 1,2 or 3. Try again."
playerMove
playerMove :: IO Int
playerMove = do
putStr "Your choice(1 to 3):"
number ... | Give a code snippet in #Haskell
21 game
You are encouraged to solve this task according to the task description, using any language you may know.
21 is a two player game, the game is played by choosing
a number (1, 2, or 3) to be added to the running total.
The game is won by the player whose chosen number causes th... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Include_a_file | Include a file | Task
Demonstrate the language's ability to include source code from other files.
See Also
Compiler/Simple file inclusion pre processor
| #Clipper | Clipper | #include "inkey.ch" | Give a code snippet in #Clipper
Task
Demonstrate the language's ability to include source code from other files.
See Also
Compiler/Simple file inclusion pre processor
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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 |... | #Nim | Nim | import strutils
let s = "The quick brown fox"
if s.startsWith("The quick"):
echo "Starts with “The quick”."
if s.endsWith("brown Fox"):
echo "Ends with “brown fox”."
if s.contains(" brown "):
echo "Contains “ brown ”."
if "quick" in s:
echo "Contains “quick”." # Alternate form for "contains".
let pos =... | Give a code snippet in #Nim
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Co... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Van_Eck_sequence | Van Eck sequence | The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term occured previously.
Example
Using ... | #Sidef | Sidef | func van_eck(n) {
var seen = Hash()
var seq = [0]
var prev = seq[-1]
for k in (1 ..^ n) {
seq << (seen.has(prev) ? (k - seen{prev}) : 0)
seen{prev} = k
prev = seq[-1]
}
seq
}
say van_eck(10)
say van_eck(1000).slice(991-1, 1000-1) | Give a code snippet in #Sidef
The sequence is generated by following this pseudo-code:
A: The first term is zero.
Repeatedly apply:
If the last term is *new* to the sequence so far then:
B: The next term is zero.
Otherwise:
C: The next term is how far back this last term occured... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Empty_program | Empty program | Task
Create the simplest possible program that is still considered "correct."
| #Avail | Avail | Module "a"
Body | Give a code snippet in #Avail
Task
Create the simplest possible program that is still considered "correct."
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Stack | Stack |
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack is accessed through its top.
The ba... | #OxygenBasic | OxygenBasic |
function f()
sys a=1,b=2,c=3,d=4
push a
push b
push c
push d
print a "," b "," c "," d 'result 1,2,3,4
a=10
b=20
c=30
d=40
print a "," b "," c "," d 'result 10,20,30,40
pop a
pop b
pop c
pop d
print a "," b "," c "," d 'result 4,3,2,1
end function
f
| Give a code snippet in #OxygenBasic
Data Structure
This illustrates a data structure, a means of storing data within a program.
You may see other such structures in the Data Structures category.
A stack is a container of elements with last in, first out access policy. Sometimes it also called LIFO.
The stack... | 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 ... | #Java | Java | import java.io.*;
public class FileIODemo {
public static void main(String[] args) {
try {
FileInputStream in = new FileInputStream("input.txt");
FileOutputStream out = new FileOutputStream("ouput.txt");
int c;
while ((c = in.read()) != -1) {
out.write(c);
}
} catch (Fi... | Give a code snippet in #Java
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 in... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Probabilistic_choice | Probabilistic choice | Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Because floating point arithmetic is invol... | #AutoHotkey | AutoHotkey | s1 := "aleph", p1 := 1/5.0 ; Input
s2 := "beth", p2 := 1/6.0
s3 := "gimel", p3 := 1/7.0
s4 := "daleth", p4 := 1/8.0
s5 := "he", p5 := 1/9.0
s6 := "waw", p6 := 1/10.0
s7 := "zayin", p7 := 1/11.0
s8 := "heth", p8 := 1-p1-p2-p3-p4-p5-p6-p7
n := 8, r0 := 0, r%n% := 1 ... | Give a code snippet in #AutoHotkey
Given a mapping between items and their required probability of occurrence, generate a million items randomly subject to the given probabilities and compare the target probability of occurrence versus the generated values.
The total of all the probabilities should equal one. (Becaus... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Topic_variable | Topic variable | Several programming languages offer syntax shortcuts to deal with the notion of "current" or "topic" variable.
A topic variable is a special variable with a very short name which can also often be omitted.
Demonstrate the utilization and behaviour of the topic variable within the language and explain or demonstrate h... | #Raku | Raku | $_ = 'Outside';
for <3 5 7 10> {
print $_;
.³.map: { say join "\t", '', $_, .², .sqrt, .log(2), OUTER::<$_>, UNIT::<$_> }
} | Give a code snippet in #Raku
Several programming languages offer syntax shortcuts to deal with the notion of "current" or "topic" variable.
A topic variable is a special variable with a very short name which can also often be omitted.
Demonstrate the utilization and behaviour of the topic variable within the languag... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Merging | Associative array/Merging | Task
Define two associative arrays, where one represents the following "base" data:
Key
Value
"name"
"Rocket Skates"
"price"
12.75
"color"
"yellow"
And the other represents "update" data:
Key
Value
"price"
15.25
"color"
"red"
"year"
1974
Merge these into a new associativ... | #PHP | PHP | <?
$base = array("name" => "Rocket Skates", "price" => 12.75, "color" => "yellow");
$update = array("price" => 15.25, "color" => "red", "year" => 1974);
$result = $update + $base; // Notice that the order is reversed
print_r($result);
?> | Give a code snippet in #PHP
Task
Define two associative arrays, where one represents the following "base" data:
Key
Value
"name"
"Rocket Skates"
"price"
12.75
"color"
"yellow"
And the other represents "update" data:
Key
Value
"price"
15.25
"color"
"red"
"year"
1974
Merg... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Quaternion_type | Quaternion type | Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number might be -3 + 2i,
wher... | #Pascal | Pascal | package Quaternion;
use List::Util 'reduce';
use List::MoreUtils 'pairwise';
sub make {
my $cls = shift;
if (@_ == 1) { return bless [ @_, 0, 0, 0 ] }
elsif (@_ == 4) { return bless [ @_ ] }
else { die "Bad number of components: @_" }
}
sub _abs { sqrt reduce { $a + $b ... | Give a code snippet in #Pascal
Quaternions are an extension of the idea of complex numbers.
A complex number has a real and complex part, sometimes written as a + bi,
where a and b stand for real numbers, and i stands for the square root of minus 1.
An example of a complex number... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Input_loop | Input loop | Input loop is part of Short Circuit's Console Program Basics selection.
Task
Read from a text stream either word-by-word or line-by-line until the stream runs out of data.
The stream will have an unknown amount of data on it.
| #Ada | Ada | with Ada.Text_Io; use Ada.Text_Io;
procedure Read_Stream is
Line : String(1..10);
Length : Natural;
begin
while not End_Of_File loop
Get_Line(Line, Length); -- read up to 10 characters at a time
Put(Line(1..Length));
-- The current line of input data may be longer than the string receiving ... | Give a code snippet in #Ada
Input loop is part of Short Circuit's Console Program Basics selection.
Task
Read from a text stream either word-by-word or line-by-line until the stream runs out of data.
The stream will have an unknown amount of data on it.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number | Guess the number | Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a "Well guessed!" message, a... | #QB64_3 | QB64 |
'Task
'Plus features: 1) AI gives suggestions about your guess
' 2) AI controls wrong input by user (numbers outer 1 and 10).
' 3) player can choose to replay the game
Randomize Timer
Dim As Integer Done, Guess, Number
Done = 1
Guess = 0
While Done
Cls
Number = Rnd * 10 + 1
Do While Number <> Gu... | Give a code snippet in #QB64_3
Task
Write a program where the program chooses a number between 1 and 10.
A player is then prompted to enter a guess. If the player guesses wrong, then the prompt appears again until the guess is correct.
When the player has made a successful guess the computer will issue a ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Averages/Arithmetic_mean | Averages/Arithmetic mean | Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an established convention for conveyin... | #Modula-2 | Modula-2 | PROCEDURE Avg;
VAR avg : REAL;
BEGIN
avg := sx / n;
InOut.WriteString ("Average = ");
InOut.WriteReal (avg, 8, 2);
InOut.WriteLn
END Avg; | Give a code snippet in #Modula-2
Task[edit]
Write a program to find the mean (arithmetic average) of a numeric vector.
In case of a zero-length input, since the mean of an empty set of numbers is ill-defined, the program may choose to behave in any way it deems appropriate, though if the programming language has an e... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_names | Number names | Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs other than positive integers (like zero, negat... | #Visual_Basic_.NET | Visual Basic .NET | Module Module1
Sub Main()
Dim i As Integer
Console.WriteLine("Enter a number")
i = Console.ReadLine()
Console.WriteLine(words(i))
Console.ReadLine()
End Sub
Function words(ByVal Number As Integer) As String
Dim small() As String = {"zero", "one", "two", "t... | Give a code snippet in #Visual_Basic_.NET
Task
Show how to spell out a number in English.
You can use a preexisting implementation or roll your own, but you should support inputs up to at least one million (or the maximum value of your language's default bounded integer type, if that's less).
Support for inputs oth... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hunt_the_Wumpus | Hunt the Wumpus | This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are:
The game is set in a cave that consists ... | #Red | Red |
Red [
Title: "Hunt the Wumpus"
Author: "Gregg Irwin"
Version: 1.0.2
Comment: {
2001 Notes:
I found an old version, in C (by Eric Raymond), which was adapted from
an even older version, in BASIC (by Magnus Olsson), that had been found
in a SIMTEL archive. It's got lineage.
As of 22-Oct-2001, it appea... | Give a code snippet in #Red
This task has been flagged for clarification. Code on this page in its current state may be flagged incorrect once this task has been clarified. See this page's Talk page for discussion.
Create a simple implementation of the classic textual game Hunt The Wumpus.
The rules are:
The game is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tokenize_a_string | Tokenize a string | Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks related to string operations:
Me... | #Dyalect | Dyalect | var str = "Hello,How,Are,You,Today"
var strings = str.Split(',')
print(values: strings, separator: ".") | Give a code snippet in #Dyalect
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word.
Display the words to the 'user', in the simplest manner possible, separated by a period.
To simplify, you may display a trailing period.
Other tasks ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/While | Loops/While | Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loops/For... | #UNIX_Shell | UNIX Shell | x=1024
while [[ $x -gt 0 ]]; do
echo $x
x=$(( $x/2 ))
done | Give a code snippet in #UNIX_Shell
Task
Start an integer value at 1024.
Loop while it is greater than zero.
Print the value (with a newline) and divide it by two each time through the loop.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Do... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Guess_the_number/With_feedback_(player) | Guess the number/With feedback (player) | Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The computer guesses, and the score... | #Sidef | Sidef | var min = 1
var max = 99
var tries = 0
var guess = pick(min..max)
print <<"EOT".chomp
\n=>> Think of a number between #{min} and #{max} and I'll guess it!\n
Press <ENTER> when are you ready...
EOT
STDIN.readline
loop {
print <<-EOT.chomp
\n=>> My guess is: #{guess} Is your number higher, lower, or equal? ... | Give a code snippet in #Sidef
Task
Write a player for the game that follows the following rules:
The scorer will choose a number between set limits. The computer player will print a guess of the target number. The computer asks for a score of whether its guess is higher than, lower than, or equal to the target. The ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Associative_array/Iteration | Associative array/Iteration | Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked ... | #Oz | Oz | declare
MyMap = unit('hello':13 'world':31 '!':71)
in
{ForAll {Record.toListInd MyMap} Show} %% pairs
{ForAll {Record.arity MyMap} Show} %% keys
{ForAll {Record.toList MyMap} Show} %% values | Give a code snippet in #Oz
Show how to iterate over the key-value pairs of an associative array, and print each pair out.
Also show how to iterate just over the keys, or the values, if there is a separate way to do that in your language.
See also
Array
Associative array: Creation, Iteration
Collections
Compou... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Josephus_problem | Josephus problem | Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting from prisoner
0
{\displaystyle 0}
,
removing eve... | #Kotlin | Kotlin | // version 1.1.3
fun josephus(n: Int, k: Int, m: Int): Pair<List<Int>, List<Int>> {
require(k > 0 && m > 0 && n > k && n > m)
val killed = mutableListOf<Int>()
val survived = MutableList(n) { it }
var start = k - 1
outer@ while (true) {
val end = survived.size - 1
var i = start
... | Give a code snippet in #Kotlin
Josephus problem is a math puzzle with a grim description:
n
{\displaystyle n}
prisoners are standing on a circle, sequentially numbered from
0
{\displaystyle 0}
to
n
−
1
{\displaystyle n-1}
.
An executioner walks along the circle, starting from prisoner
0
{... | 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... | #PowerShell | PowerShell | $x = @(1, 2, 3, 1e11)
$y = @(1, 1.4142135623730951, 1.7320508075688772, 316227.76601683791)
$xprecision = 3
$yprecision = 5
$arr = foreach($i in 0..($x.count-1)) {
[pscustomobject]@{x = "{0:g$xprecision}" -f $x[$i]; y = "{0:g$yprecision}" -f $y[$i]}
}
($arr | format-table -HideTableHeaders | Out-String).Trim() >... | Give a code snippet in #PowerShell
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Chaos_game | Chaos game | The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the reference points. Add a ... | #J | J |
Note 'plan, Working in complex plane'
Make an equilateral triangle.
Make a list of N targets
Starting with a random point near the triangle,
iteratively generate new points.
plot the new points.
j has a particularly rich notation for numbers.
1ad_90 specifies a complex number with radius 1
a... | Give a code snippet in #J
The Chaos Game is a method of generating the attractor of an iterated function system (IFS).
One of the best-known and simplest examples creates a fractal, using a polygon and an initial point selected at random.
Task
Play the Chaos Game using the corners of an equilateral triangle as the... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_case | String case | Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not reversable.
Show any additional... | #Vala | Vala |
string s = "alphaBeta";
// stores ALPHABETA to string
string s_upper = s.up();
// stores alphabeta to string
string s_lower = s.down();
| Give a code snippet in #Vala
Task
Take the string alphaBETA and demonstrate how to convert it to:
upper-case and
lower-case
Use the default encoding of a string literal or plain ASCII if there is no string literal in your language.
Note: In some languages alphabets toLower and toUpper is not re... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Add_a_variable_to_a_class_instance_at_runtime | Add a variable to a class instance at runtime | Demonstrate how to dynamically add variables to an object (a class instance) at runtime.
This is useful when the methods/variables of an instance are based on a data file that isn't available until runtime. Hal Fulton gives an example of creating an OO CSV parser at An Exercise in Metaprogramming with Ruby. This is re... | #Perl | Perl | package Empty;
# Constructor. Object is hash.
sub new { return bless {}, shift; }
package main;
# Object.
my $o = Empty->new;
# Set runtime variable (key => value).
$o->{'foo'} = 1; | Give a code snippet in #Perl
Demonstrate how to dynamically add variables to an object (a class instance) at runtime.
This is useful when the methods/variables of an instance are based on a data file that isn't available until runtime. Hal Fulton gives an example of creating an OO CSV parser at An Exercise in Metapro... | 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 | ... | #REXX | REXX | /*REXX program demonstrates a way to represent any set of real numbers and usage. */
call quertySet 1, 3, '[1,2)'
call quertySet , , '[0,2) union (1,3)'
call quertySet , , '[0,1) union (2,3]'
call quertySet , , '[0,2] inter (1,3)'
call quertySet , , '(1,2) ∩ (2,3]'
call quertySet ... | Give a code snippet in #REXX
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/Sorting_algorithms/Strand_sort | Sorting algorithms/Strand 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
... | #Kotlin | Kotlin | // version 1.1.2
fun <T : Comparable<T>> strandSort(l: List<T>): List<T> {
fun merge(left: MutableList<T>, right: MutableList<T>): MutableList<T> {
val res = mutableListOf<T>()
while (!left.isEmpty() && !right.isEmpty()) {
if (left[0] <= right[0]) {
res.add(left[0])
... | Give a code snippet in #Kotlin
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/Deconvolution/1D | Deconvolution/1D | The convolution of two functions
F
{\displaystyle {\mathit {F}}}
and
H
{\displaystyle {\mathit {H}}}
of
an integer variable is defined as the function
G
{\displaystyle {\mathit {G}}}
satisfying
G
(
n
)
=
∑
m
=
−
∞
∞
F
(
m
)
H
(
n
−
m
)
{\displaystyle G(n)=\sum _{m=-\inft... | #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language |
deconv[f_List, g_List] :=
Module[{A =
SparseArray[
Table[Band[{n, 1}] -> f[[n]], {n, 1, Length[f]}], {Length[g], Length[f] - 1}]},
Take[LinearSolve[A, g], Length[g] - Length[f] + 1]]
| Give a code snippet in #Mathematica_.2F_Wolfram_Language
The convolution of two functions
F
{\displaystyle {\mathit {F}}}
and
H
{\displaystyle {\mathit {H}}}
of
an integer variable is defined as the function
G
{\displaystyle {\mathit {G}}}
satisfying
G
(
n
)
=
∑
m
=
−
∞
∞
... | christopher/rosetta-code |
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