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/Cuban_primes | Cuban primes | The name cuban has nothing to do with Cuba (the country), but has to do with the
fact that cubes (3rd powers) play a role in its definition.
Some definitions of cuban primes
primes which are the difference of two consecutive cubes.
primes of the form: (n+1)3 - n3.
primes of the form: n3 - ... | #Wren | Wren | import "/fmt" for Fmt
var start = System.clock
var primes = [3, 5]
var cutOff = 200
var bigOne = 100000
var cubans = []
var bigCuban = ""
var c = 0
var showEach = true
var u = 0
var v = 1
for (i in 1...(1<<20)) {
var found = false
u = u + 6
v = v + u
var mx = v.sqrt.floor
for (item in primes) {... | Give a code snippet in #Wren
The name cuban has nothing to do with Cuba (the country), but has to do with the
fact that cubes (3rd powers) play a role in its definition.
Some definitions of cuban primes
primes which are the difference of two consecutive cubes.
primes of the form: (n+1)3 - n3.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_termination | Program termination |
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finalizers/destructors, run-on-exit hooks... | #SenseTalk | SenseTalk |
if problemCondition then exit all
| Give a code snippet in #SenseTalk
Task
Show the syntax for a complete stoppage of a program inside a conditional.
This includes all threads/processes which are part of your program.
Explain the cleanup (or lack thereof) caused by the termination (allocated memory, database connections, open files, object finali... | 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
... | #PL.2FI | PL/I | s = reverse(s); | Give a code snippet in #PL.2FI
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/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #REXX | REXX | do until userNumber==75000
| Give a code snippet in #REXX
User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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... | #Ol | Ol |
(define x (* 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2)) ; 2^64
(print (* x x))
| Give a code snippet in #Ol
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... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Display_a_linear_combination | Display a linear combination | Task
Display a finite linear combination in an infinite vector basis
(
e
1
,
e
2
,
…
)
{\displaystyle (e_{1},e_{2},\ldots )}
.
Write a function that, when given a finite list of scalars
(
α
1
,
α
2
,
…
)
{\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )}
,
creates a string representing t... | #Sidef | Sidef | func linear_combination(coeffs) {
var res = ""
for e,f in (coeffs.kv) {
given(f) {
when (1) {
res += "+e(#{e+1})"
}
when (-1) {
res += "-e(#{e+1})"
}
case (.> 0) {
res += "+#{f}*e(#{e+1})"
... | Give a code snippet in #Sidef
Task
Display a finite linear combination in an infinite vector basis
(
e
1
,
e
2
,
…
)
{\displaystyle (e_{1},e_{2},\ldots )}
.
Write a function that, when given a finite list of scalars
(
α
1
,
α
2
,
…
)
{\displaystyle (\alpha ^{1},\alpha ^{2},\ldots )}
,
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_common_divisor | Greatest common divisor | Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest common measure.
Related tas... | #Seed7 | Seed7 | const func integer: gcd (in var integer: a, in var integer: b) is func
result
var integer: gcd is 0;
local
var integer: help is 0;
begin
while a <> 0 do
help := b rem a;
b := a;
a := help;
end while;
gcd := b;
end func; | Give a code snippet in #Seed7
Greatest common divisor
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Find the greatest common divisor (GCD) of two integers.
Greatest common divisor is also known as greatest common factor (gcf) and greatest... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_limit_of_recursion | Find limit of recursion | Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| #NetRexx | NetRexx | /* NetRexx */
options replace format comments java crossref symbols binary
import java.lang.management.
memoryInfo()
digDeeper(0)
/**
* Just keep digging
* @param level depth gauge
*/
method digDeeper(level = int) private static binary
do
digDeeper(level + 1)
catch ex = Error
System.out.println('Re... | Give a code snippet in #NetRexx
Find limit of recursion is part of Short Circuit's Console Program Basics selection.
Task
Find the limit of recursion.
| 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... | #Haskell | Haskell | import Control.Monad.ST
import Data.STRef
accumulator :: (Num a) => a -> ST s (a -> ST s a)
accumulator sum0 = do
sum <- newSTRef sum0
return $ \n -> do
modifySTRef sum (+ n)
readSTRef sum
main :: IO ()
main = print foo
where foo = runST $ do
x <- accumulator 1
x ... | Give a code snippet in #Haskell
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 p... | 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.)
| #Lily | Lily | # This is a single-line comment | Give a code snippet in #Lily
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/Singly-linked_list/Element_definition | Singly-linked list/Element definition | singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element definition, Element insertion, Lis... | #Sidef | Sidef | var node = Hash.new(
data => 'say what',
next => foo_node,
);
node{:next} = bar_node; # mutable | Give a code snippet in #Sidef
singly-linked list
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
Linked list
Queue: Definition, Usage
Set
Singly-linked list: Element def... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greatest_element_of_a_list | Greatest element of a list | Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| #Arturo | Arturo | arr: [5 4 2 9 7 3]
print max arr | Give a code snippet in #Arturo
Task
Create a function that returns the maximum value in a provided set of values,
where the number of values may not be known until run-time.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Draw_a_sphere | Draw a sphere | Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a Deathstar
| #Kotlin | Kotlin | // version 1.0.6
const val shades = ".:!*oe&#%@"
val light = doubleArrayOf(30.0, 30.0, -50.0)
fun normalize(v: DoubleArray) {
val len = Math.sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2])
v[0] /= len; v[1] /= len; v[2] /= len
}
fun dot(x: DoubleArray, y: DoubleArray): Double {
val d = x[0] * y[0] + x[... | Give a code snippet in #Kotlin
Task
Draw a sphere.
The sphere can be represented graphically, or in ASCII art, depending on the language capabilities.
Either static or rotational projection is acceptable for this task.
Related tasks
draw a cuboid
draw a rotating cube
write language name in 3D ASCII
draw a D... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Call_an_object_method | Call an object method | In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static or class method, and an instance m... | #Quackery | Quackery | ( ---------------- zen object orientation -------------- )
[ immovable
]this[ swap do ]done[ ] is object ( --> )
[ ]'[ ] is method ( --> [ )
[ method
[ dup share
swap put ] ] is localise ( --> [ )
[ method [ release ] ] is delocali... | Give a code snippet in #Quackery
In object-oriented programming a method is a function associated with a particular class or object. In most forms of object oriented implementations methods can be static, associated with the class itself; or instance, associated with an instance of a class.
Show how to call a static ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Halt_and_catch_fire | Halt and catch fire | Task
Create a program that crashes as soon as possible, with as few lines of code as possible. Be smart and don't damage your computer, ok?
The code should be syntactically valid. It should be possible to insert [a subset of] your submission into another program, presumably to help debug it, or perhaps for use when an... | #GW-BASIC | GW-BASIC | 0 gosub 0 | Give a code snippet in #GW-BASIC
Task
Create a program that crashes as soon as possible, with as few lines of code as possible. Be smart and don't damage your computer, ok?
The code should be syntactically valid. It should be possible to insert [a subset of] your submission into another program, presumably to help de... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:... | #Frink | Frink | for f = sort[files["."], {|a,b| lexicalCompare[a.getName[], b.getName[]]}]
println[f.getName[]] | Give a code snippet in #Frink
Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Exampl... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Gamma_function | Gamma function | Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/library function.
The Gamma funct... | #Wren | Wren | import "/fmt" for Fmt
import "/math" for Math
var stirling = Fn.new { |x| (2 * Num.pi / x).sqrt * (x / Math.e).pow(x) }
System.print(" x\tStirling\t\tLanczos\n")
for (i in 1..20) {
var d = i / 10
System.write("%(Fmt.f(4, d, 2))\t")
System.write("%(Fmt.f(16, stirling.call(d), 14))\t")
System.print("%... | Give a code snippet in #Wren
Task
Implement one algorithm (or more) to compute the Gamma (
Γ
{\displaystyle \Gamma }
) function (in the real field only).
If your language has the function as built-in or you know a library which has it, compare your implementation's results with the results of the built-in/libr... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Ackermann_function | Ackermann function | The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
{
n
+
1
if
m
=
0
A
(
m
... | #Golfscript | Golfscript | {
:_n; :_m;
_m 0= {_n 1+}
{_n 0= {_m 1- 1 ack}
{_m 1- _m _n 1- ack ack}
if}
if
}:ack; | Give a code snippet in #Golfscript
The Ackermann function is a classic example of a recursive function, notable especially because it is not a primitive recursive function. It grows very quickly in value, as does the size of its call tree.
The Ackermann function is usually defined as follows:
A
(
m
,
n
)
=
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fusc_sequence | Fusc sequence |
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition starts with unity, not zero. Th... | #Picat | Picat | main =>
println("First 61 fusc numbers:"),
println([fusc(I) : I in 0..60]),
nl,
println("Points in the sequence whose length is greater than any previous fusc number length:\n"),
println(" Index fusc Len"),
largest_fusc_string(20_000_000).
table
fusc(0) = 0.
fusc(1) = 1.
fusc(N) = fusc(N//2), eve... | Give a code snippet in #Picat
Definitions
The fusc integer sequence is defined as:
fusc(0) = 0
fusc(1) = 1
for n>1, the nth term is defined as:
if n is even; fusc(n) = fusc(n/2)
if n is odd; fusc(n) = fusc((n-1)/2) + fusc((n+1)/2)
Note that MathWorld's definition st... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Tau_function | Tau function | Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| #Rust | Rust | // returns the highest power of i that is a factor of n,
// and n divided by that power of i
fn factor_exponent(n: i32, i: i32) -> (i32, i32) {
if n % i == 0 {
let (a, b) = factor_exponent(n / i, i);
(a + 1, b)
} else {
(0, n)
}
}
fn tau(n: i32) -> i32 {
for i in 2..(n+1) {
if n % i == 0 {
let (count, ... | Give a code snippet in #Rust
Given a positive integer, count the number of its positive divisors.
Task
Show the result for the first 100 positive integers.
Related task
Tau number
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Hostname | Hostname | Task
Find the name of the host on which the routine is running.
| #Lingo | Lingo |
sx = xtra("Shell").new()
if the platform contains "win" then
hostname = sx.shell_cmd("hostname", ["eol":RETURN]).line[1] -- win 7 or later
else
hostname = sx.shell_cmd("hostname", RETURN).line[1]
end if | Give a code snippet in #Lingo
Task
Find the name of the host on which the routine is running.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/String_concatenation | String concatenation | String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string literal.
To illustrate the operat... | #Gambas | Gambas | Public sub main()
DIM bestclub AS String
DIM myconcat AS String
bestclub = "Liverpool"
myconcat = bestclub & " Football Club"
Print myconcat
End | Give a code snippet in #Gambas
String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string li... | christopher/rosetta-code | |
http://rosettacode.org/wiki/User_input/Text | User input/Text | User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| #UNIX_Shell | UNIX Shell | #!/bin/sh
read string
read integer
read -p 'Enter a number: ' number
echo "The number is $number" | Give a code snippet in #UNIX_Shell
User input/Text is part of Short Circuit's Console Program Basics selection.
Task
Input a string and the integer 75000 from the text console.
See also: User input/Graphical
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Yin_and_yang | Yin and yang | One well-known symbol of the philosophy of duality known as yin and yang is the taijitu.
Task
Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.
Generate and display the symbol for two different (small) sizes.
| #BCPL | BCPL | get "libhdr"
let circle(x, y, c, r) = (r*r) >= (x/2) * (x/2) + (y-c) * (y-c)
let pixel(x, y, r) =
circle(x, y, -r/2, r/6) -> '#',
circle(x, y, r/2, r/6) -> '.',
circle(x, y, -r/2, r/2) -> '.',
circle(x, y, r/2, r/2) -> '#',
circle(x, y, 0, r) -> x<0 -> '.', '#',
' '
let yinyang(r) ... | Give a code snippet in #BCPL
One well-known symbol of the philosophy of duality known as yin and yang is the taijitu.
Task
Create a function that, given a parameter representing size, generates such a symbol scaled to the requested size.
Generate and display the symbol for two different (small) sizes.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Sort_an_integer_array | Sort an integer array |
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_W | ALGOL W | begin
% use the quicksort procedure from the Sorting_Algorithms/Quicksort task %
% Quicksorts in-place the array of integers v, from lb to ub - external %
procedure quicksort ( integer array v( * )
; integer value lb, ub
) ; algol "sortingAlgorithms_Quicksort... | Give a code snippet in #ALGOL_W
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/Apply_a_callback_to_an_array | Apply a callback to an array | Task
Take a combined set of elements and apply a function to each element.
| #Oberon-2 | Oberon-2 |
MODULE ApplyCallBack;
IMPORT
Out := NPCT:Console;
TYPE
Fun = PROCEDURE (x: LONGINT): LONGINT;
Ptr2Ary = POINTER TO ARRAY OF LONGINT;
VAR
a: ARRAY 5 OF LONGINT;
x: ARRAY 3 OF LONGINT;
r: Ptr2Ary;
PROCEDURE Min(x,y: LONGINT): LONGINT;
BEGIN
IF x <= y THEN RETURN x ELSE RETURN y END;
END Min;... | Give a code snippet in #Oberon-2
Task
Take a combined set of elements and apply a function to each element.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Unix/ls | Unix/ls | Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Example output
For the list of paths:... | #Clojure | Clojure | (def files (sort (filter #(= "." (.getParent %)) (file-seq (clojure.java.io/file ".")))))
(doseq [n files] (println (.getName n))) | Give a code snippet in #Clojure
Task
Write a program that will list everything in the current folder, similar to:
the Unix utility “ls” [1] or
the Windows terminal command “DIR”
The output must be sorted, but printing extended details and producing multi-column output is not required.
Exam... | christopher/rosetta-code | |
http://rosettacode.org/wiki/99_bottles_of_beer | 99 bottles of beer | Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98 bottles of beer
Take one dow... | #Idris | Idris |
beerSong : Fin 100 -> String
beerSong x = verses x where
bottlesOfBeer : Fin n -> String
bottlesOfBeer fZ = "No more bottles of beer"
bottlesOfBeer (fS fZ) = "1 bottle of beer"
bottlesOfBeer k = (show (finToInteger k)) ++ " bottles of beer"
verse : Fin n -> String
verse fZ ... | Give a code snippet in #Idris
Task
Display the complete lyrics for the song: 99 Bottles of Beer on the Wall.
The beer song
The lyrics follow this form:
99 bottles of beer on the wall
99 bottles of beer
Take one down, pass it around
98 bottles of beer on the wall
98 bottles of beer on the wall
98... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Fibonacci_sequence | Fibonacci sequence | The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are generally considered too slow ... | #Scala | Scala | def fib(i: Int): Int = i match {
case 0 => 0
case 1 => 1
case _ => fib(i - 1) + fib(i - 2)
} | Give a code snippet in #Scala
The Fibonacci sequence is a sequence Fn of natural numbers defined recursively:
F0 = 0
F1 = 1
Fn = Fn-1 + Fn-2, if n>1
Task
Write a function to generate the nth Fibonacci number.
Solutions can be iterative or recursive (though recursive solutions are... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Formatted_numeric_output | Formatted numeric output | Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| #Ursala | Ursala | #import flo
x = 7.125
#show+
t = <printf/'%09.3f' x> | Give a code snippet in #Ursala
Task
Express a number in decimal as a fixed-length string with leading zeros.
For example, the number 7.125 could be expressed as 00007.125.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/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
| #Phix | Phix |
Functions are normally internal to a program. If they are at the nesting level
immediately within the program, they are accessible from anywhere in the program.
Functions can also be encapsuled in a package, and the function name exported.
Functions can be compiled separately, and then linked with a program
in wh... | Give a code snippet in #Phix
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/Integer_sequence | Integer sequence | Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations limits. For example, if integer... | #Kotlin | Kotlin | import java.math.BigInteger
// version 1.0.5-2
fun main(args: Array<String>) {
// print until 2147483647
(0..Int.MAX_VALUE).forEach { println(it) }
// print forever
var n = BigInteger.ZERO
while (true) {
println(n)
n += BigInteger.ONE
}
} | Give a code snippet in #Kotlin
Task
Create a program that, when run, would display all integers from 1 to ∞ (or any relevant implementation limit), in sequence (i.e. 1, 2, 3, 4, etc) if given enough time.
An example may not be able to reach arbitrarily-large numbers based on implementations l... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Write_to_Windows_event_log | Write to Windows event log | Task
Write script status to the Windows Event Log
| #zkl | zkl | zkl: System.cmd(0'|eventcreate "/T" "INFORMATION" "/ID" "123" "/D" "Rosetta Code example"|) | Give a code snippet in #zkl
Task
Write script status to the Windows Event Log
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Copy_a_string | Copy a string | This task is about copying a string.
Task
Where it is relevant, distinguish between copying the contents of a string
versus making an additional reference to an existing string.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty string (assignment)
Counting
W... | #Factor | Factor | "This is a mutable string." dup ! reference
"Let's make a deal!" dup clone ! copy
"New" " string" append . ! new string
"New string" | Give a code snippet in #Factor
This task is about copying a string.
Task
Where it is relevant, distinguish between copying the contents of a string
versus making an additional reference to an existing string.
Other tasks related to string operations:
Metrics
Array length
String length
Copy a string
Empty ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nth_root | Nth root | Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| #ALGOL_68 | ALGOL 68 | REAL default p = 0.001;
PROC nth root = (INT n, LONG REAL a, p)LONG REAL:
(
[2]LONG REAL x := (a, a/n);
WHILE ABS(x[2] - x[1]) > p DO
x := (x[2], ((n-1)*x[2] + a/x[2]**(n-1))/n )
OD;
x[2]
);
PRIO ROOT = 8;
OP ROOT = (INT n, LONG REAL a)LONG REAL: nth root(n, a, default p);
OP ROOT = (INT n, INT a)LONG... | Give a code snippet in #ALGOL_68
Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Currying | Currying |
This page uses content from Wikipedia. The original article was at Currying. 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
Create a simple demonstrative example of Currying in a specific la... | #Kotlin | Kotlin | // version 1.1.2
fun curriedAdd(x: Int) = { y: Int -> x + y }
fun main(args: Array<String>) {
val a = 2
val b = 3
val sum = curriedAdd(a)(b)
println("$a + $b = $sum")
} | Give a code snippet in #Kotlin
This page uses content from Wikipedia. The original article was at Currying. 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
Create a simple demonstrative exam... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Digital_root | Digital root | The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}
, repeating until
X
{\displ... | #BBC_BASIC | BBC BASIC | *FLOAT64
PRINT "Digital root of 627615 is "; FNdigitalroot(627615, 10, p) ;
PRINT " (additive persistence " ; p ")"
PRINT "Digital root of 39390 is "; FNdigitalroot(39390, 10, p) ;
PRINT " (additive persistence " ; p ")"
PRINT "Digital root of 588225 is "; FNdigitalroot(588225, 10, p... | Give a code snippet in #BBC_BASIC
The digital root,
X
{\displaystyle X}
, of a number,
n
{\displaystyle n}
, is calculated:
find
X
{\displaystyle X}
as the sum of the digits of
n
{\displaystyle n}
find a new
X
{\displaystyle X}
by summing the digits of
X
{\displaystyle X}... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Greyscale_bars/Display | Greyscale bars/Display | The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of grey until we have a white bar on the right ha... | #ZX_Spectrum_Basic | ZX Spectrum Basic | 10 REM wind the colour down or use a black and white television to see greyscale bars
20 REM The ZX Spectrum display is 32 columns wide, so we have 8 columns of 4 spaces
25 BORDER 0: CLS
30 FOR r=0 TO 21: REM There are 22 rows
40 FOR c=0 TO 7: REM We use the native colour sequence here
50 PRINT PAPER c;" ";: REM fou... | Give a code snippet in #ZX_Spectrum_Basic
The task is to display a series of vertical greyscale bars (contrast bars) with a sufficient number of bars to span the entire width of the display.
For the top quarter of the display, the left hand bar should be black, and we then incrementally step through six shades of gre... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Visualize_a_tree | Visualize a tree | A tree structure (i.e. a rooted, connected acyclic graph) is often used in programming.
It's often helpful to visually examine such a structure.
There are many ways to represent trees to a reader, such as:
indented text (à la unix tree command)
nested HTML tables
hierarchical GUI widgets
2D or ... | #C.2B.2B | C++ | #include <functional>
#include <iostream>
#include <random>
class BinarySearchTree {
private:
struct Node {
int key;
Node *left, *right;
Node(int k) : key(k), left(nullptr), right(nullptr) {
//empty
}
} *root;
public:
BinarySearchTree() : root(nullptr) {
... | Give a code snippet in #C.2B.2B
A tree structure (i.e. a rooted, connected acyclic graph) is often used in programming.
It's often helpful to visually examine such a structure.
There are many ways to represent trees to a reader, such as:
indented text (à la unix tree command)
nested HTML tables
hie... | 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 ... | #Phix | Phix | function emHalf(integer n)
return floor(n/2)
end function
function emDouble(integer n)
return n*2
end function
function emIsEven(integer n)
return (remainder(n,2)=0)
end function
function emMultiply(integer a, integer b)
integer sum = 0
while a!=0 do
if not emIsEven(a) then sum += b end if... | Give a code snippet in #Phix
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 wr... | 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
| #Haskell | Haskell | -- Due to Haskell's module system, textual includes are rarely needed. In
-- general, one will import a module, like so:
import SomeModule
-- For actual textual inclusion, alternate methods are available. The Glasgow
-- Haskell Compiler runs the C preprocessor on source code, so #include may be
-- used:
#include "SomeM... | Give a code snippet in #Haskell
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/Longest_increasing_subsequence | Longest increasing subsequence | Calculate and show here a longest increasing subsequence of the list:
{
3
,
2
,
6
,
4
,
5
,
1
}
{\displaystyle \{3,2,6,4,5,1\}}
And of the list:
{
0
,
8
,
4
,
12
,
2
,
10
,
6
,
14
,
1
,
9
,
5
,
13
,
3
,
11
,
7
,
15
}
{\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15\}}
Note that a list may have m... | #AutoHotkey | AutoHotkey | Lists := [[3,2,6,4,5,1], [0,8,4,12,2,10,6,14,1,9,5,13,3,11,7,15]]
for k, v in Lists {
D := LIS(v)
MsgBox, % D[D.I].seq
}
LIS(L) {
D := []
for i, v in L {
D[i, "Length"] := 1, D[i, "Seq"] := v, D[i, "Val"] := v
Loop, % i - 1 {
if(D[A_Index].Val < v && D[A_Index].Length + 1 > D[i].Length) {
D[i].Length... | Give a code snippet in #AutoHotkey
Calculate and show here a longest increasing subsequence of the list:
{
3
,
2
,
6
,
4
,
5
,
1
}
{\displaystyle \{3,2,6,4,5,1\}}
And of the list:
{
0
,
8
,
4
,
12
,
2
,
10
,
6
,
14
,
1
,
9
,
5
,
13
,
3
,
11
,
7
,
15
}
{\displaystyle \{0,8,4,12,2,10,6,14,1,9,5,13,3,11,7... | christopher/rosetta-code | |
http://rosettacode.org/wiki/File_size | File size | Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| #Kotlin | Kotlin | // version 1.0.6
import java.io.File
fun main(args: Array<String>) {
val paths = arrayOf("input.txt", "c:\\input.txt")
for (path in paths)
println("Length of $path is ${File(path).length()} bytes")
} | Give a code snippet in #Kotlin
Verify the size of a file called input.txt for a file in the current working directory, and another one in the file system root.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Quine | Quine | A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
self-reproducing program ... | #FALSE | FALSE | ["'[,34,$!34,'],!"]'[,34,$!34,'],! | Give a code snippet in #FALSE
A quine is a self-referential program that can,
without any external access, output its own source.
A quine (named after Willard Van Orman Quine) is also known as:
self-reproducing automata (1972)
self-replicating program or self-replicating computer program
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/24_game/Solve | 24 game/Solve | task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| #Yabasic | Yabasic | operators$ = "*+-/"
space$ = " "
sub present()
clear screen
print "24 Game"
print "============\n"
print "Computer provide 4 numbers (1 to 9). With operators +, -, * and / you try to\nobtain 24."
print "Use Reverse Polish Notation (fi... | Give a code snippet in #Yabasic
task
Write a program that takes four digits, either from user input or by random generation, and computes arithmetic expressions following the rules of the 24 game.
Show examples of solutions generated by the program.
Related task
Arithmetic Evaluator
| 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
| #Clean | Clean | Start = "Hello world!" | Give a code snippet in #Clean
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/Loop_over_multiple_arrays_simultaneously | Loop over multiple arrays simultaneously | Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For this example, loop over the arrays:
... | #8080_Assembly | 8080 Assembly | org 100h
lxi b,0 ; Let (B)C be the array index
outer: lxi d,As ; Use DE to walk the array-of-arrays
inner: xchg ; Swap DE and HL (array-of-array pointer into HL)
mov e,m ; Load low byte of array pointer into E
inx h
mov d,m ; Load high byte of array pointer into D
inx h
xchg ; Array base in HL, array-of-array... | Give a code snippet in #8080_Assembly
Task
Loop over multiple arrays (or lists or tuples or whatever they're called in
your language) and display the i th element of each.
Use your language's "for each" loop if it has one, otherwise iterate
through the collection in order with some other loop.
For t... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Sorting_algorithms/Heapsort | Sorting algorithms/Heapsort |
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
... | #Scala | Scala | def heapSort[T](a: Array[T])(implicit ord: Ordering[T]) {
import scala.annotation.tailrec // Ensure functions are tail-recursive
import ord._
val indexOrdering = Ordering by a.apply
def numberOfLeaves(heapSize: Int) = (heapSize + 1) / 2
def children(i: Int, heapSize: Int) = {
val leftChild = i * 2 +... | Give a code snippet in #Scala
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 so... | 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... | #Scheme | Scheme | (define (compose f g) (lambda (x) (f (g x))))
;; or:
(define ((compose f g) x) (f (g x)))
;; or to compose an arbitrary list of 1 argument functions:
(define-syntax compose
(lambda (x)
(syntax-case x ()
((_) #'(lambda (y) y))
((_ f) #'f)
((_ f g h ...) #'(lambda (y) (f ((compose g h ...... | Give a code snippet in #Scheme
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/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... | #Sidef | Sidef | func encode(str) {
str.gsub(/((.)(\2*))/, {|a,b| "#{a.len}#{b}" });
}
func decode(str) {
str.gsub(/(\d+)(.)/, {|a,b| b * a.to_i });
} | Give a code snippet in #Sidef
Run-length encoding
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Given a string containing uppercase characters (A-Z), compress repeated 'runs' of the same character by storing the length of that run, and provide a func... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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"
| #Rust | Rust | use std::env;
fn main(){
let args: Vec<_> = env::args().collect();
println!("{:?}", args);
} | Give a code snippet in #Rust
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/Closures/Value_capture | Closures/Value capture | Task
Create a list of ten functions, in the simplest manner possible (anonymous functions are encouraged), such that the function at index i (you may choose to start i from either 0 or 1), when run, should return the square of the index, that is, i 2.
Display the result of runnin... | #Nemerle | Nemerle | using System.Console;
module Closures
{
Main() : void
{
def f(x) { fun() { x ** 2 } }
def funcs = $[f(x) | x in $[0 .. 10]].ToArray(); // using array for easy indexing
WriteLine($"$(funcs[4]())");
WriteLine($"$(funcs[2]())");
}
} | Give a code snippet in #Nemerle
Task
Create a list of ten functions, in the simplest manner possible (anonymous functions are encouraged), such that the function at index i (you may choose to start i from either 0 or 1), when run, should return the square of the index, that is, i ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Non-decimal_radices/Output | Non-decimal radices/Output | Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routines of your programming langu... | #Ada | Ada | with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;
with Ada.Text_IO; use Ada.Text_IO;
procedure Test_Integer_Text_IO is
begin
for I in 1..33 loop
Put (I, Width =>3, Base=> 10);
Put (I, Width =>7, Base=> 16);
Put (I, Width =>6, Base=> 8);
New_Line;
end loop;
end Test_Integer_Text_IO; | Give a code snippet in #Ada
Programming languages often have built-in routines to convert a non-negative integer for printing in different number bases. Such common number bases might include binary, Octal and Hexadecimal.
Task
Print a small range of integers in some different bases, as supported by standard routi... | 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,... | #Objeck | Objeck |
bundle Default {
class Arithmetic {
function : Main(args : System.String[]), Nil {
array := Int->New[2];
array[0] := 13;
array[1] := 7;
(array[0] + array[1])->PrintLine();
}
}
}
| Give a code snippet in #Objeck
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 retr... | 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.
| #D | D | void main() {
import std.algorithm: filter, equal;
immutable data = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
auto evens = data.filter!(x => x % 2 == 0); // Lazy.
assert(evens.equal([2, 4, 6, 8, 10]));
} | Give a code snippet in #D
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/Case-sensitivity_of_identifiers | Case-sensitivity of identifiers | Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, Samba and Bernie.
For a language... | #Aime | Aime | text dog, Dog, DOG;
dog = "Benjamin";
Dog = "Samba";
DOG = "Bernie";
o_form("The three dogs are named ~, ~ and ~.\n", dog, Dog, DOG); | Give a code snippet in #Aime
Three dogs (Are there three dogs or one dog?) is a code snippet used to illustrate the lettercase sensitivity of the programming language. For a case-sensitive language, the identifiers dog, Dog and DOG are all different and we should get the output:
The three dogs are named Benjamin, Sam... | 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... | #Aime | Aime | integer j;
list l, x;
text s, t;
l = list("---------- 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 #Aime
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 space... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_prepend | String prepend |
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 |... | #M2000_Interpreter | M2000 Interpreter |
Module PrependString {
A$="Hello"
A$+=" World"
Print A$
}
PrependString
| Give a code snippet in #M2000_Interpreter
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... | 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.)
| #J | J | NB. Text that follows 'NB.' has no effect on execution.
0 : 0
Multi-line comments may be placed in strings,
like this.
)
Note 'example'
Another way to record multi-line comments as text is to use 'Note', which is actually
a simple program that makes it clearer when defined text is used only to provide comment.
)
... | Give a code snippet in #J
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/Active_Directory/Search_for_a_user | Active Directory/Search for a user | Make sure you Connect to Active Directory
| #ooRexx | ooRexx | /* Rexx */
do
LDAP_URL = 'ldap://localhost:11389'
LDAP_DN_STR = 'uid=admin,ou=system'
LDAP_CREDS = '********'
LDAP_BASE_DN = 'ou=users,o=mojo'
LDAP_SCOPE = 'sub'
LDAP_FILTER = '"(&(objectClass=person)(&(uid=*mil*)))"'
LDAP_ATTRIBUTES = '"dn" "cn" "sn" "uid"'
ldapCommand = ... | Give a code snippet in #ooRexx
Make sure you Connect to Active Directory
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Middle_three_digits | Middle three digits | Task
Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible.
Note: The order of the middle digits should be preserved.
Your function should be tested with the following values;... | #Klong | Klong | items::[123 12345 1234567 987654321 10001 -10001 -123 -100 100 -12345 1 2 -1 -10 2002 -2002 0]
mid3::{[d k];:[3>k::#$#x;"small":|0=k!2;"even";(-d)_(d::_(k%2)-1)_$#x]}
.p(mid3'items) | Give a code snippet in #Klong
Task
Write a function/procedure/subroutine that is called with an integer value and returns the middle three digits of the integer if possible or a clear indication of an error if this is not possible.
Note: The order of the middle digits should be preserved.
Your function should be te... | 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... | #JavaScript | JavaScript | var assoc = {};
assoc['foo'] = 'bar';
assoc['another-key'] = 3;
// dot notation can be used if the property name is a valid identifier
assoc.thirdKey = 'we can also do this!';
assoc[2] = "the index here is the string '2'";
//using JavaScript's object literal notation
var assoc = {
foo: 'bar',
'another-key': 3... | Give a code snippet in #JavaScript
Task
The goal is to create an associative array (also known as a dictionary, map, or hash).
Related tasks:
Associative arrays/Iteration
Hash from two arrays
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Find_Chess960_starting_position_identifier | Find Chess960 starting position identifier | As described on the Chess960 page, Chess960 (a.k.a Fischer Random Chess, Chess9LX) is a variant of chess where the array of pieces behind the pawns is randomized at the start of the game to minimize the value of opening theory "book knowledge". That task is to generate legal starting positions, and some of the solution... | #Perl | Perl | use strict;
use warnings;
use feature 'say';
use List::AllUtils 'indexes';
sub sp_id {
my $setup = shift // 'RNBQKBNR';
8 == length $setup or die 'Illegal position: should have exactly eight pieces';
1 == @{[ $setup =~ /$_/g ]} or die "Illegal position: should ha... | Give a code snippet in #Perl
As described on the Chess960 page, Chess960 (a.k.a Fischer Random Chess, Chess9LX) is a variant of chess where the array of pieces behind the pawns is randomized at the start of the game to minimize the value of opening theory "book knowledge". That task is to generate legal starting posit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Number_reversal_game | Number reversal game | Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
The score is the count of the reversa... | #JavaScript | JavaScript | <html>
<head>
<title>Number Reversal Game</title>
</head>
<body>
<div id="start"></div>
<div id="progress"></div>
<div id="score"></div>
<script type="text/javascript"> | Give a code snippet in #JavaScript
Task
Given a jumbled list of the numbers 1 to 9 that are definitely not in
ascending order.
Show the list, and then ask the player how many digits from the
left to reverse.
Reverse those digits, then ask again, until all the digits end up in ascending order.
T... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Program_name | Program name | The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script name to a language's internal A... | #F.23 | F# | #light (*
exec fsharpi --exec $0 --quiet
*)
let scriptname =
let args = System.Environment.GetCommandLineArgs()
let arg0 = args.[0]
if arg0.Contains("fsi") then
let arg1 = args.[1]
if arg1 = "--exec" then
args.[2]
else
arg1
else
arg0
let m... | Give a code snippet in #F.23
The task is to programmatically obtain the name used to invoke the program. (For example determine whether the user ran "python hello.py", or "python hellocaller.py", a program importing the code from "hello.py".)
Sometimes a multiline shebang is necessary in order to provide the script n... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Loops/Do-while | Loops/Do-while | Start with a value at 0. Loop while value mod 6 is not equal to 0.
Each time through the loop, add 1 to the value then print it.
The loop must execute at least once.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downward for
Loops/For
Loo... | #E | E | var x := 0
__loop(fn {
x += 1
println(x)
x % 6 != 0 # this is the return value of the function
}) | Give a code snippet in #E
Start with a value at 0. Loop while value mod 6 is not equal to 0.
Each time through the loop, add 1 to the value then print it.
The loop must execute at least once.
Related tasks
Loop over multiple arrays simultaneously
Loops/Break
Loops/Continue
Loops/Do-while
Loops/Downw... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Textonyms | Textonyms | When entering text on a phone's digital pad it is possible that a particular combination of digits corresponds to more than one word. Such are called textonyms.
Assuming the digit keys are mapped to letters as follows:
2 -> ABC
3 -> DEF
4 -> GHI
5 -> JKL
6 -> MNO
7 -> PQRS
8 -> TUV
9 -... | #REXX | REXX | /*REXX program counts and displays the number of textonyms that are in a dictionary file*/
parse arg iFID . /*obtain optional fileID from the C.L. */
if iFID=='' | iFID=="," then iFID='UNIXDICT.TXT' /*Not specified? Then use the default.*/
@.= 0 ... | Give a code snippet in #REXX
When entering text on a phone's digital pad it is possible that a particular combination of digits corresponds to more than one word. Such are called textonyms.
Assuming the digit keys are mapped to letters as follows:
2 -> ABC
3 -> DEF
4 -> GHI
5 -> JKL
6 -> MNO
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Evaluate_binomial_coefficients | Evaluate binomial coefficients | This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
1
)
(
n
−
2
)
…
(
n
−
k
+
1
)
k
(
k
−
1... | #Icon_and_Unicon | Icon and Unicon | link math, factors
procedure main()
write("choose(5,3)=",binocoef(5,3))
end | Give a code snippet in #Icon_and_Unicon
This programming task, is to calculate ANY binomial coefficient.
However, it has to be able to output
(
5
3
)
{\displaystyle {\binom {5}{3}}}
, which is 10.
This formula is recommended:
(
n
k
)
=
n
!
(
n
−
k
)
!
k
!
=
n
(
n
−
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Stern-Brocot_sequence | Stern-Brocot sequence | For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member of the sequence and its prece... | #REXX | REXX | /*REXX program generates & displays a Stern─Brocot sequence; finds 1─based indices; GCDs*/
parse arg N idx fix chk . /*get optional arguments from the C.L. */
if N=='' | N=="," then N= 15 /*Not specified? Then use the default.*/
if idx=='' | idx=="," then idx= 10 ... | Give a code snippet in #REXX
For this task, the Stern-Brocot sequence is to be generated by an algorithm similar to that employed in generating the Fibonacci sequence.
The first and second members of the sequence are both 1:
1, 1
Start by considering the second member of the sequence
Sum the considered member... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Harshad_or_Niven_series | Harshad or Niven series | The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task is to create a function/method/... | #Tcl | Tcl | # Determine if the given number is a member of the class of Harshad numbers
proc isHarshad {n} {
if {$n < 1} {return false}
set sum [tcl::mathop::+ {*}[split $n ""]]
return [expr {$n%$sum == 0}]
}
# Get the first 20 numbers that satisfy the condition
for {set n 1; set harshads {}} {[llength $harshads] < 2... | Give a code snippet in #Tcl
The Harshad or Niven numbers are positive integers ≥ 1 that are divisible by the sum of their digits.
For example, 42 is a Harshad number as 42 is divisible by (4 + 2) without remainder.
Assume that the series is defined as the numbers in increasing order.
Task
The task is... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nth_root | Nth root | Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| #C.23 | C# |
static void Main(string[] args)
{
Console.WriteLine(NthRoot(81,2,.001));
Console.WriteLine(NthRoot(1000,3,.001));
Console.ReadLine();
}
public static double NthRoot(double A,int n, double p)
{
double _n= (double) n;
double[] x = new double[2];
x[0] = A;
x[1] = A/_n;
while(Math.Abs(x[0] -x[1... | Give a code snippet in #C.23
Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Fractran | Fractran | FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway.
A FRACTRAN program is an ordered list of positive fractions
P
=
(
f
1
,
f
2
,
…
,
f
m
)
{\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})}
, together with an initial positive integer input
n
... | #11l | 11l | F fractran(prog, =val, limit)
V fracts = prog.split(‘ ’).map(p -> p.split(‘/’).map(i -> Int(i)))
[Float] r
L(n) 0 .< limit
r [+]= val
L(p) fracts
I val % p[1] == 0
val = p[0] * val / p[1]
L.break
R r
print(fractran(‘17/91 78/85 19/51 23/38 29/33 77/29 95/23 77/... | Give a code snippet in #11l
FRACTRAN is a Turing-complete esoteric programming language invented by the mathematician John Horton Conway.
A FRACTRAN program is an ordered list of positive fractions
P
=
(
f
1
,
f
2
,
…
,
f
m
)
{\displaystyle P=(f_{1},f_{2},\ldots ,f_{m})}
, together with an initial ... | 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... | #Lisaac | Lisaac | + i : INTEGER;
i := 1024;
{ i > 0 }.while_do {
i.println;
i := i / 2;
}; | Give a code snippet in #Lisaac
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/Downwa... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Strip_block_comments | Strip block comments | A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos should at least handle simple, non-ne... | #Tcl | Tcl | proc stripBlockComment {string {openDelimiter "/*"} {closeDelimiter "*/"}} {
# Convert the delimiters to REs by backslashing all non-alnum characters
set openAsRE [regsub -all {\W} $openDelimiter {\\&}]
set closeAsRE [regsub -all {\W} $closeDelimiter {\\&}]
# Now remove the blocks using a dynamic non-... | Give a code snippet in #Tcl
A block comment begins with a beginning delimiter and ends with a ending delimiter, including the delimiters. These delimiters are often multi-character sequences.
Task
Strip block comments from program text (of a programming language much like classic C).
Your demos should a... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FTP | FTP | Task
Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
| #C | C |
#include <ftplib.h>
int main(void)
{
netbuf *nbuf;
FtpInit();
FtpConnect("kernel.org", &nbuf);
FtpLogin("anonymous", "", nbuf);
FtpOptions(FTPLIB_CONNMODE, FTPLIB_PASSIVE, nbuf);
FtpChdir("pub/linux/kernel", nbuf);
FtpDir((void*)0, ".", nbuf);
FtpGet("ftp.README", "README", FTPLIB_... | Give a code snippet in #C
Task
Connect to a server, change directory, list its contents and download a file as binary using the FTP protocol. Use passive mode if available.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Documentation | Documentation |
See also
Related task: Comments
Related task: Here_document
| #Lua | Lua | --- Converts degrees to radians (summary).
-- Given an angle measure in degrees, return an equivalent angle measure in radians (long description).
-- @param deg the angle measure in degrees
-- @return the angle measure in radians
-- @see rad2deg
function deg2rad(deg) return deg*math.pi/180 end | Give a code snippet in #Lua
See also
Related task: Comments
Related task: Here_document
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Unicode_strings | Unicode strings | As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is your programming language for ... | #J | J | '♥♦♣♠'
♥♦♣♠ | Give a code snippet in #J
As the world gets smaller each day, internationalization becomes more and more important. For handling multiple languages, Unicode is your best friend.
It is a very capable tool, but also quite complex compared to older single- and double-byte character encodings.
How well prepared is you... | 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 |... | #XSLT | XSLT | <xsl:template name="compare">
<xsl:param name="a" select="1"/>
<xsl:param name="b" select="2"/>
<fo:block>
<xsl:choose>
<xsl:when test="$a < $b">a < b</xsl:when>
<xsl:when test="$a > $b">a > b</xsl:when>
<xsl:when test="$a = $b">a = b</xsl:when>
</xsl:choose>
</fo:block>
</xsl:templ... | Give a code snippet in #XSLT
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
C... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Read_a_file_line_by_line | Read a file line by line | Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| #NewLISP | NewLISP |
(set 'in-file (open "filename" "read"))
(while (read-line in-file)
(write-line))
(close in-file) | Give a code snippet in #NewLISP
Read a file one line at a time,
as opposed to reading the entire file at once.
Related tasks
Read a file character by character
Input loop.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Symmetric_difference | Symmetric difference | Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{\displaystyle (A\cup B)\setminus (A... | #Run_BASIC | Run BASIC |
setA$ = "John,Bob,Mary,Serena"
setB$ = "Jim,Mary,John,Bob"
x$ = b$(setA$,setB$)
print word$(x$,1,",")
c$ = c$ + x$
x$ = b$(setB$,setA$)
print word$(x$,1,",")
print c$;x$
end
function b$(a$,b$)
i = 1
while word$(a$,i,",") <> ""
a1$ = word$(a$,i,",")
j = instr(b$,a1$)
if j <> 0 then b$ = left$(b$,j-1) + m... | Give a code snippet in #Run_BASIC
Task
Given two sets A and B, compute
(
A
∖
B
)
∪
(
B
∖
A
)
.
{\displaystyle (A\setminus B)\cup (B\setminus A).}
That is, enumerate the items that are in A or B but not both. This set is called the symmetric difference of A and B.
In other words:
(
A
∪
B
)
∖
(
A
∩
B
)
{... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Pointers_and_references | Pointers and references |
Basic Data Operation
This is a basic data operation. It represents a fundamental action on a basic data type.
You may see other such operations in the Basic Data Operations category, or:
Integer Operations
Arithmetic |
Comparison
Boolean Operations
Bitwise |
Logical
String Operations
Concatenation |
Interpolation |... | #VBA | VBA | Dim samplevariable as New Object
Dim anothervariable as Object
Set anothervariable = sameplevariable | Give a code snippet in #VBA
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/XML/XPath | XML/XPath | Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniCorp Store #45x10^3">
<section name="heal... | #AArch64_Assembly | AArch64 Assembly |
/* ARM assembly AARCH64 Raspberry PI 3B */
/* program xpathXml64.s */
/*******************************************/
/* Constantes file */
/*******************************************/
/* for this file see task include a file in language AArch64 assembly*/
.include "../includeConstantesARM... | Give a code snippet in #AArch64_Assembly
Perform the following three XPath queries on the XML Document below:
//item[1]: Retrieve the first "item" element
//price/text(): Perform an action on each "price" element (print it out)
//name: Get an array of all the "name" elements
XML Document:
<inventory title="OmniC... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Null_object | Null object |
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your language by checking to see if an ob... | #Kotlin | Kotlin | // version 1.1.0
fun main(args: Array<String>) {
val i: Int = 3 // non-nullable Int type - can't be assigned null
println(i)
val j: Int? = null // nullable Int type - can be assigned null
println(j)
println(null is Nothing?) // test that null is indeed of type Nothing?
} | Give a code snippet in #Kotlin
Null (or nil) is the computer science concept of an undefined or unbound object.
Some languages have an explicit way to access the null object, and some don't.
Some languages distinguish the null object from undefined values, and some don't.
Task
Show how to access null in your lang... | christopher/rosetta-code | |
http://rosettacode.org/wiki/FizzBuzz | FizzBuzz | Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuzz (instead of the number)
... | #HicEst | HicEst | DO i = 1, 100
IF( MOD(i, 15) == 0 ) THEN
WRITE() "FizzBuzz"
ELSEIF( MOD(i, 5) == 0 ) THEN
WRITE() "Buzz"
ELSEIF( MOD(i, 3) == 0 ) THEN
WRITE() "Fizz"
ELSE
WRITE() i
ENDIF
ENDDO | Give a code snippet in #HicEst
Task
Write a program that prints the integers from 1 to 100 (inclusive).
But:
for multiples of three, print Fizz (instead of the number)
for multiples of five, print Buzz (instead of the number)
for multiples of both three and five, print FizzBuz... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Nth_root | Nth root | Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| #J | J | '`N X NP' =. (0 { [)`(1 { [)`(2 { [)
iter =. N %~ (NP * ]) + X % ] ^ NP
nth_root =: (, , _1+[) iter^:_ f. ]
10 nth_root 7131.5^10
7131.5 | Give a code snippet in #J
Task
Implement the algorithm to compute the principal nth root
A
n
{\displaystyle {\sqrt[{n}]{A}}}
of a positive real number A, as explained at the Wikipedia page.
| 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.)
| #Eiffel | Eiffel | -- inline comment, continues until new line | Give a code snippet in #Eiffel
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/Doubly-linked_list/Definition | Doubly-linked list/Definition | Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data type
Doubly-linked list: Definitio... | #PicoLisp | PicoLisp | +------------> start
|
+--+--+-----+
| | | ---+---> end
+-----+-----+
| Give a code snippet in #PicoLisp
Define the data structure for a complete Doubly Linked List.
The structure should support adding elements to the head, tail and middle of the list.
The structure should not allow circular loops
See also
Array
Associative array: Creation, Iteration
Collections
Compound data t... | 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
| #ABAP | ABAP | REPORT zgoodbyeworld.
WRITE 'Hello world!'. | Give a code snippet in #ABAP
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/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... | #Ursa | Ursa | #
# arithmetic mean
#
decl int<> input
decl int i
for (set i 1) (< i (size args)) (inc i)
append (int args<i>) input
end for
out (/ (+ input) (size input)) endl console | Give a code snippet in #Ursa
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 estab... | christopher/rosetta-code | |
http://rosettacode.org/wiki/String_concatenation | String concatenation | String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string literal.
To illustrate the operat... | #REBOL | REBOL | s: "hello"
print s1: rejoin [s " literal"]
print s1 | Give a code snippet in #REBOL
String concatenation
You are encouraged to solve this task according to the task description, using any language you may know.
Task
Create a string variable equal to any text value.
Create another string variable whose value is the original variable concatenated with another string lit... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Count_occurrences_of_a_substring | Count occurrences of a substring | Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
It should return an integer cou... | #Scheme | Scheme | gosh> (use gauche.lazy)
#<undef>
gosh> (length (lrxmatch "th" "the three truths"))
3
gosh> (length (lrxmatch "abab" "ababababab"))
2
| Give a code snippet in #Scheme
Task
Create a function, or show a built-in function, to count the number of non-overlapping occurrences of a substring inside a string.
The function should take two arguments:
the first argument being the string to search, and
the second a substring to be searched for.
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/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 ... | #Logtalk | Logtalk |
/* Houses logical puzzle: who owns the zebra and who drinks water?
1) Five colored houses in a row, each with an owner, a pet, cigarettes, and a drink.
2) The English lives in the red house.
3) The Spanish has a dog.
4) They drink coffee in the green house.
5) The Ukrainian drinks tea.
... | Give a code snippet in #Logtalk
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 ... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Matrix-exponentiation_operator | Matrix-exponentiation operator | Most programming languages have a built-in implementation of exponentiation for integers and reals only.
Task
Demonstrate how to implement matrix exponentiation as an operator.
| #GAP | GAP | # Matrix exponentiation is built-in
A := [[0 , 1], [1, 1]];
PrintArray(A);
# [ [ 0, 1 ],
# [ 1, 1 ] ]
PrintArray(A^10);
# [ [ 34, 55 ],
# [ 55, 89 ] ] | Give a code snippet in #GAP
Most programming languages have a built-in implementation of exponentiation for integers and reals only.
Task
Demonstrate how to implement matrix exponentiation as an operator.
| christopher/rosetta-code | |
http://rosettacode.org/wiki/Exponentiation_with_infix_operators_in_(or_operating_on)_the_base | Exponentiation with infix operators in (or operating on) the base | (Many programming languages, especially those with extended─precision integer arithmetic, usually
support one of **, ^, ↑ or some such for exponentiation.)
Some languages treat/honor infix operators when performing exponentiation (raising
numbers to some power by the language's exponentiation operator, if ... | #J | J | format=: ''&$: :([: ; (a: , [: ":&.> [) ,. '{}' ([ (E. <@}.;._1 ]) ,) ])
S=: 'x = {} p = {} -x^p {} -(x)^p {} (-x)^p {} -(x^p) {}'
explicit=: dyad def 'S format~ 2 2 4 4 4 4 ":&> x,y,(-x^y),(-(x)^y),((-x)^y),(-(x^y))'
tacit=: S format~ 2 2 4 4 4 4 ":&> [`]`([:-^)`([:-^)`((... | Give a code snippet in #J
(Many programming languages, especially those with extended─precision integer arithmetic, usually
support one of **, ^, ↑ or some such for exponentiation.)
Some languages treat/honor infix operators when performing exponentiation (raising
numbers to some power by the language's exp... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Factorial | Factorial | Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a number.
Solutions can be iterat... | #Lua | Lua | function fact(n)
return n > 0 and n * fact(n-1) or 1
end | Give a code snippet in #Lua
Definitions
The factorial of 0 (zero) is defined as being 1 (unity).
The Factorial Function of a positive integer, n, is defined as the product of the sequence:
n, n-1, n-2, ... 1
Task
Write a function to return the factorial of a num... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Hello_world/Line_printer | Hello world/Line printer | Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With some systems, a line printer can be... | #PostScript | PostScript | <</PageSize [595 842]>> setpagedevice % set page size to DIN A4
/Courier findfont % use Courier
12 scalefont setfont % 12 pt
28 802 moveto % 1 cm from the top and left edges
(Hello world) show % draw the string | Give a code snippet in #PostScript
Task
Cause a line printer attached to the computer to print a line containing the message: Hello World!
Note
A line printer is not the same as standard output.
A line printer was an older-style printer which prints one line at a time to a continuous ream of paper.
With... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Catalan_numbers | Catalan numbers | Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
for
n
≥
0.
{\displaystyle C... | #Quackery | Quackery | [ 1 over times [ over i 1+ + * ] nip ] is 2n!/n! ( n --> n )
[ times [ i 1+ / ] ] is /n! ( n --> n )
[ dup 2n!/n! swap 1+ /n! ] is catalan ( n --> n )
15 times [ i^ dup echo say " : " catalan echo cr ] | Give a code snippet in #Quackery
Catalan numbers
You are encouraged to solve this task according to the task description, using any language you may know.
Catalan numbers are a sequence of numbers which can be defined directly:
C
n
=
1
n
+
1
(
2
n
n
)
=
(
2
n
)
!
(
n
+
1
)
!
n
!
... | christopher/rosetta-code | |
http://rosettacode.org/wiki/Numerical_integration | Numerical integration | Write functions to calculate the definite integral of a function ƒ(x) using all five of the following methods:
rectangular
left
right
midpoint
trapezium
Simpson's
composite
Your functions should take in the upper and lower bounds (a and b), and the number of approximations to make in that range (n).
Assume t... | #TI-89_BASIC | TI-89 BASIC | #import std
#import nat
#import flo
(integral_by "m") ("f","a","b","n") =
iprod ^(* ! div\float"n" minus/"b" "a",~&) ("m" "f")*ytp (ari successor "n")/"a" "b" | Give a code snippet in #TI-89_BASIC
Write functions to calculate the definite integral of a function ƒ(x) using all five of the following methods:
rectangular
left
right
midpoint
trapezium
Simpson's
composite
Your functions should take in the upper and lower bounds (a and b), and the number of approximations... | 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... | #Wren | Wren | import "io" for Stdin, Stdout
import "random" for Random
var rand = Random.new()
var n = rand.int(1, 11) // computer number from 1..10 inclusive
while (true) {
System.write("Your guess 1-10 : ")
Stdout.flush()
var guess = Num.fromString(Stdin.readLine())
if (n == guess) {
System.print("Well gu... | Give a code snippet in #Wren
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/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... | #PHP | PHP | <?php
function accumulator($start){
return create_function('$x','static $v='.$start.';return $v+=$x;');
}
$acc = accumulator(5);
echo $acc(5), "\n"; //prints 10
echo $acc(10), "\n"; //prints 20
?> | Give a code snippet in #PHP
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 passe... | christopher/rosetta-code |
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