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http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #Elixir | Elixir | iex(1)> URI.encode("http://foo bar/", &URI.char_unreserved?/1)
"http%3A%2F%2Ffoo%20bar%2F" |
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #Erlang | Erlang | 1> http_uri:encode("http://foo bar/").
"http%3A%2F%2Ffoo%20bar%2F"
|
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #DM | DM | // Both of the following declarations can be seen as a tree,
// var -> <varname>
var/x
var y
// They can also be defined like this.
// This is once again a tree structure, but this time the "var" only appears once, and the x and y are children.
var
x
y
// And like this, still a tree structure.
var/x, y
|
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #Diego | Diego | add_var(v1);
dim(v1);
add_var(v1, v2, v3, v4);
dim(v1, v2, v3, v4);
add_var(isRaining)_datatype(boolean);
dim(isRaining)_datatype(boolean);
add_var(greeting)_dt(string);
dim(greeting)_dt(string);
add_var({date}, birthdate);
dim({date}, birthdate); |
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 A:
0
Using B:
0 0
Using C:
0 0 1
Using B:
0 0 1 0
Using C: (zero last occurred two steps back - before the one)
0 0 1 0 2
Using B:
0 0 1 0 2 0
Using C: (two last occurred two steps back - before the zero)
0 0 1 0 2 0 2 2
Using C: (two last occurred one step back)
0 0 1 0 2 0 2 2 1
Using C: (one last appeared six steps back)
0 0 1 0 2 0 2 2 1 6
...
Task
Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
Use it to display here, on this page:
The first ten terms of the sequence.
Terms 991 - to - 1000 of the sequence.
References
Don't Know (the Van Eck Sequence) - Numberphile video.
Wikipedia Article: Van Eck's Sequence.
OEIS sequence: A181391.
| #Go | Go | package main
import "fmt"
func main() {
const max = 1000
a := make([]int, max) // all zero by default
for n := 0; n < max-1; n++ {
for m := n - 1; m >= 0; m-- {
if a[m] == a[n] {
a[n+1] = n - m
break
}
}
}
fmt.Println("The first ten terms of the Van Eck sequence are:")
fmt.Println(a[:10])
fmt.Println("\nTerms 991 to 1000 of the sequence are:")
fmt.Println(a[990:])
} |
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 A:
0
Using B:
0 0
Using C:
0 0 1
Using B:
0 0 1 0
Using C: (zero last occurred two steps back - before the one)
0 0 1 0 2
Using B:
0 0 1 0 2 0
Using C: (two last occurred two steps back - before the zero)
0 0 1 0 2 0 2 2
Using C: (two last occurred one step back)
0 0 1 0 2 0 2 2 1
Using C: (one last appeared six steps back)
0 0 1 0 2 0 2 2 1 6
...
Task
Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
Use it to display here, on this page:
The first ten terms of the sequence.
Terms 991 - to - 1000 of the sequence.
References
Don't Know (the Van Eck Sequence) - Numberphile video.
Wikipedia Article: Van Eck's Sequence.
OEIS sequence: A181391.
| #Haskell | Haskell | import Data.List (elemIndex)
import Data.Maybe (maybe)
vanEck :: Int -> [Int]
vanEck n = reverse $ iterate go [] !! n
where
go [] = [0]
go xxs@(x:xs) = maybe 0 succ (elemIndex x xs) : xxs
main :: IO ()
main = do
print $ vanEck 10
print $ drop 990 (vanEck 1000) |
http://rosettacode.org/wiki/Vampire_number | Vampire number | A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
together they consist of exactly the same decimal digits as the original number
at most one of them has a trailing zero
An example of a vampire number and its fangs: 1260 : (21, 60)
Task
Print the first 25 vampire numbers and their fangs.
Check if the following numbers are vampire numbers and, if so, print them and their fangs:
16758243290880, 24959017348650, 14593825548650
Note that a vampire number can have more than one pair of fangs.
See also
numberphile.com.
vampire search algorithm
vampire numbers on OEIS
| #Perl | Perl | #!/usr/bin/perl
use warnings;
use strict;
use feature qw(say);
sub fangs {
my $vampire = shift;
my $length = length 0 + $vampire;
return if $length % 2;
my $fang_length = $length / 2;
my $from = '1' . '0' x ($fang_length - 1);
my $to = '9' x $fang_length;
my $sorted = join q(), sort split //, $vampire;
my @fangs;
for my $f1 ($from .. 1 + sqrt $vampire) {
next if $vampire % $f1;
my $f2 = $vampire / $f1;
next if $sorted ne join q(), sort split //, $f1 . $f2;
next if 2 == grep '0' eq substr($_, -1 , 1), $f1, $f2; # Needed for the 26th number.
push @fangs, [$f1, $f2];
}
return @fangs;
}
my $count = 0;
my $i = 9;
while ($count < 25) {
$i++;
my @f = fangs($i);
$count++, say join ' ', "$count. $i:", map "[@$_]", @f if @f;
}
say join ' ', $_, map "[@$_]", fangs($_) for 16758243290880, 24959017348650, 14593825548650; |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #Lua | Lua | function varar(...)
for i, v in ipairs{...} do print(v) end
end |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #M2000_Interpreter | M2000 Interpreter |
Module CheckIt {
\\ Works for numbers and strings (letters in M2000)
Function Variadic {
\\ print a letter for each type in function stack
Print Envelope$()
\\Check types using Match
Print Match("NNSNNS")
=stack.size
While not Empty {
if islet then {print letter$} else print number
}
}
M=Variadic(1,2,"Hello",3,4,"Bye")
Print M
\\ K is a poiner to Array
K=(1,2,"Hello 2",3,4,"Bye 2")
\\ !K pass all items to function's stack
M=Variadic(!K)
}
Checkit
Module CheckIt2 {
Function Variadic {
\\ [] return a pointer to stack, and leave a new stack as function's stack
a=[]
\\ a is a pointer to stack
\\ objects just leave a space, and cursor move to next column (spread on lines)
Print a
}
M=Variadic(1,2,"Hello",3,4,"Bye")
Print M
\\ K is a poiner to Array
K=(1,2,"Hello 2",3,4,"Bye 2")
\\ !K pass all items to function stack
M=Variadic(!K)
}
Checkit2
|
http://rosettacode.org/wiki/Vector | Vector | Task
Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented.
The Vector may be initialized in any reasonable way.
Start and end points, and direction
Angular coefficient and value (length)
The four operations to be implemented are:
Vector + Vector addition
Vector - Vector subtraction
Vector * scalar multiplication
Vector / scalar division
| #Rust | Rust | use std::fmt;
use std::ops::{Add, Div, Mul, Sub};
#[derive(Copy, Clone, Debug)]
pub struct Vector<T> {
pub x: T,
pub y: T,
}
impl<T> fmt::Display for Vector<T>
where
T: fmt::Display,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
if let Some(prec) = f.precision() {
write!(f, "[{:.*}, {:.*}]", prec, self.x, prec, self.y)
} else {
write!(f, "[{}, {}]", self.x, self.y)
}
}
}
impl<T> Vector<T> {
pub fn new(x: T, y: T) -> Self {
Vector { x, y }
}
}
impl Vector<f64> {
pub fn from_polar(r: f64, theta: f64) -> Self {
Vector {
x: r * theta.cos(),
y: r * theta.sin(),
}
}
}
impl<T> Add for Vector<T>
where
T: Add<Output = T>,
{
type Output = Self;
fn add(self, other: Self) -> Self::Output {
Vector {
x: self.x + other.x,
y: self.y + other.y,
}
}
}
impl<T> Sub for Vector<T>
where
T: Sub<Output = T>,
{
type Output = Self;
fn sub(self, other: Self) -> Self::Output {
Vector {
x: self.x - other.x,
y: self.y - other.y,
}
}
}
impl<T> Mul<T> for Vector<T>
where
T: Mul<Output = T> + Copy,
{
type Output = Self;
fn mul(self, scalar: T) -> Self::Output {
Vector {
x: self.x * scalar,
y: self.y * scalar,
}
}
}
impl<T> Div<T> for Vector<T>
where
T: Div<Output = T> + Copy,
{
type Output = Self;
fn div(self, scalar: T) -> Self::Output {
Vector {
x: self.x / scalar,
y: self.y / scalar,
}
}
}
fn main() {
use std::f64::consts::FRAC_PI_3;
println!("{:?}", Vector::new(4, 5));
println!("{:.4}", Vector::from_polar(3.0, FRAC_PI_3));
println!("{}", Vector::new(2, 3) + Vector::new(4, 6));
println!("{:.4}", Vector::new(5.6, 1.3) - Vector::new(4.2, 6.1));
println!("{:.4}", Vector::new(3.0, 4.2) * 2.3);
println!("{:.4}", Vector::new(3.0, 4.2) / 2.3);
println!("{}", Vector::new(3, 4) / 2);
} |
http://rosettacode.org/wiki/Vector | Vector | Task
Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented.
The Vector may be initialized in any reasonable way.
Start and end points, and direction
Angular coefficient and value (length)
The four operations to be implemented are:
Vector + Vector addition
Vector - Vector subtraction
Vector * scalar multiplication
Vector / scalar division
| #Scala | Scala | object Vector extends App {
case class Vector2D(x: Double, y: Double) {
def +(v: Vector2D) = Vector2D(x + v.x, y + v.y)
def -(v: Vector2D) = Vector2D(x - v.x, y - v.y)
def *(s: Double) = Vector2D(s * x, s * y)
def /(s: Double) = Vector2D(x / s, y / s)
override def toString() = s"Vector($x, $y)"
}
val v1 = Vector2D(5.0, 7.0)
val v2 = Vector2D(2.0, 3.0)
println(s"v1 = $v1")
println(s"v2 = $v2\n")
println(s"v1 + v2 = ${v1 + v2}")
println(s"v1 - v2 = ${v1 - v2}")
println(s"v1 * 11 = ${v1 * 11.0}")
println(s"11 * v2 = ${v2 * 11.0}")
println(s"v1 / 2 = ${v1 / 2.0}")
println(s"\nSuccessfully completed without errors. [total ${scala.compat.Platform.currentTime - executionStart} ms]")
} |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar cipher
Rot-13
Substitution Cipher
| #Rust | Rust | use std::ascii::AsciiExt;
static A: u8 = 'A' as u8;
fn uppercase_and_filter(input: &str) -> Vec<u8> {
let alphabet = b"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
let mut result = Vec::new();
for c in input.chars() {
// Ignore anything that is not in our short list of chars. We can then safely cast to u8.
if alphabet.iter().any(|&x| x as char == c) {
result.push(c.to_ascii_uppercase() as u8);
}
}
return result;
}
fn vigenere(key: &str, text: &str, is_encoding: bool) -> String {
let key_bytes = uppercase_and_filter(key);
let text_bytes = uppercase_and_filter(text);
let mut result_bytes = Vec::new();
for (i, c) in text_bytes.iter().enumerate() {
let c2 = if is_encoding {
(c + key_bytes[i % key_bytes.len()] - 2 * A) % 26 + A
} else {
(c + 26 - key_bytes[i % key_bytes.len()]) % 26 + A
};
result_bytes.push(c2);
}
String::from_utf8(result_bytes).unwrap()
}
fn main() {
let text = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!";
let key = "VIGENERECIPHER";
println!("Text: {}", text);
println!("Key: {}", key);
let encoded = vigenere(key, text, true);
println!("Code: {}", encoded);
let decoded = vigenere(key, &encoded, false);
println!("Back: {}", decoded);
} |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar cipher
Rot-13
Substitution Cipher
| #Scala | Scala |
object Vigenere {
def encrypt(msg: String, key: String) : String = {
var result: String = ""
var j = 0
for (i <- 0 to msg.length - 1) {
val c = msg.charAt(i)
if (c >= 'A' && c <= 'Z') {
result += ((c + key.charAt(j) - 2 * 'A') % 26 + 'A').toChar
j = (j + 1) % key.length
}
}
return result
}
def decrypt(msg: String, key: String) : String = {
var result: String = ""
var j = 0
for (i <- 0 to msg.length - 1) {
val c = msg.charAt(i)
if (c >= 'A' && c <= 'Z') {
result += ((c - key.charAt(j) + 26) % 26 + 'A').toChar
j = (j + 1) % key.length
}
}
return result
}
}
println("Encrypt text ABC => " + Vigenere.encrypt("ABC", "KEY"))
println("Decrypt text KFA => " + Vigenere.decrypt("KFA", "KEY"))
|
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #ERRE | ERRE |
PROGRAM VECTORPRODUCT
!$DOUBLE
TYPE TVECTOR=(X,Y,Z)
DIM A:TVECTOR,B:TVECTOR,C:TVECTOR
DIM AA:TVECTOR,BB:TVECTOR,CC:TVECTOR
DIM DD:TVECTOR,EE:TVECTOR,FF:TVECTOR
PROCEDURE DOTPRODUCT(DD.,EE.->DOTP)
DOTP=DD.X*EE.X+DD.Y*EE.Y+DD.Z*EE.Z
END PROCEDURE
PROCEDURE CROSSPRODUCT(DD.,EE.->FF.)
FF.X=DD.Y*EE.Z-DD.Z*EE.Y
FF.Y=DD.Z*EE.X-DD.X*EE.Z
FF.Z=DD.X*EE.Y-DD.Y*EE.X
END PROCEDURE
PROCEDURE SCALARTRIPLEPRODUCT(AA.,BB.,CC.->SCALARTP)
CROSSPRODUCT(BB.,CC.->FF.)
DOTPRODUCT(AA.,FF.->SCALARTP)
END PROCEDURE
PROCEDURE VECTORTRIPLEPRODUCT(AA.,BB.,CC.->FF.)
CROSSPRODUCT(BB.,CC.->FF.)
CROSSPRODUCT(AA.,FF.->FF.)
END PROCEDURE
PROCEDURE PRINTVECTOR(AA.)
PRINT("(";AA.X;",";AA.Y;",";AA.Z;")")
END PROCEDURE
BEGIN
A.X=3 A.Y=4 A.Z=5
B.X=4 B.Y=3 B.Z=5
C.X=-5 C.Y=-12 C.Z=-13
PRINT("A: ";) PRINTVECTOR(A.)
PRINT("B: ";) PRINTVECTOR(B.)
PRINT("C: ";) PRINTVECTOR(C.)
PRINT
DOTPRODUCT(A.,B.->DOTP)
PRINT("A.B =";DOTP)
CROSSPRODUCT(A.,B.->FF.)
PRINT("AxB =";) PRINTVECTOR(FF.)
SCALARTRIPLEPRODUCT(A.,B.,C.->SCALARTP)
PRINT("A.(BxC)=";SCALARTP)
VECTORTRIPLEPRODUCT(A.,B.,C.->FF.)
PRINT("Ax(BxC)=";) PRINTVECTOR(FF.)
END PROGRAM
|
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded checksum is correct.
Demonstrate that your code passes the test-cases listed below.
Details
The format of an ISIN is as follows:
┌───────────── a 2-character ISO country code (A-Z)
│ ┌─────────── a 9-character security code (A-Z, 0-9)
│ │ ┌── a checksum digit (0-9)
AU0000XVGZA3
For this task, you may assume that any 2-character alphabetic sequence is a valid country code.
The checksum can be validated as follows:
Replace letters with digits, by converting each character from base 36 to base 10, e.g. AU0000XVGZA3 →1030000033311635103.
Perform the Luhn test on this base-10 number.
There is a separate task for this test: Luhn test of credit card numbers.
You don't have to replicate the implementation of this test here ─── you can just call the existing function from that task. (Add a comment stating if you did this.)
Test cases
ISIN
Validity
Comment
US0378331005
valid
US0373831005
not valid
The transposition typo is caught by the checksum constraint.
U50378331005
not valid
The substitution typo is caught by the format constraint.
US03378331005
not valid
The duplication typo is caught by the format constraint.
AU0000XVGZA3
valid
AU0000VXGZA3
valid
Unfortunately, not all transposition typos are caught by the checksum constraint.
FR0000988040
valid
(The comments are just informational. Your function should simply return a Boolean result. See #Raku for a reference solution.)
Related task:
Luhn test of credit card numbers
Also see
Interactive online ISIN validator
Wikipedia article: International Securities Identification Number
| #Kotlin | Kotlin | // version 1.1
object Isin {
val r = Regex("^[A-Z]{2}[A-Z0-9]{9}[0-9]$")
fun isValid(s: String): Boolean {
// check format
if (!s.matches(r)) return false
// validate checksum
val sb = StringBuilder()
for (c in s) {
when (c) {
in '0'..'9' -> sb.append(c)
in 'A'..'Z' -> sb.append((c.toInt() - 55).toString().padStart(2, '0'))
}
}
return luhn(sb.toString())
}
private fun luhn(s: String): Boolean {
fun sumDigits(n: Int) = n / 10 + n % 10
val t = s.reversed()
val s1 = t.filterIndexed { i, _ -> i % 2 == 0 }.sumBy { it - '0' }
val s2 = t.filterIndexed { i, _ -> i % 2 == 1 }.map { sumDigits((it - '0') * 2) }.sum()
return (s1 + s2) % 10 == 0
}
}
fun main(args: Array<String>) {
val isins = arrayOf(
"US0378331005", "US0373831005", "U50378331005", "US03378331005",
"AU0000XVGZA3", "AU0000VXGZA3", "FR0000988040"
)
for (isin in isins) {
println("$isin\t -> ${if (Isin.isValid(isin)) "valid" else "not valid"}")
}
} |
http://rosettacode.org/wiki/Van_der_Corput_sequence | Van der Corput sequence | When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of
2
0
{\displaystyle 2^{0}}
; the digit in the next column to the left has a multiplier of
2
1
{\displaystyle 2^{1}}
; and so on.
So in the following table:
0.
1.
10.
11.
...
the binary number "10" is
1
×
2
1
+
0
×
2
0
{\displaystyle 1\times 2^{1}+0\times 2^{0}}
.
You can also have binary digits to the right of the “point”, just as in the decimal number system. In that case, the digit in the place immediately to the right of the point has a weight of
2
−
1
{\displaystyle 2^{-1}}
, or
1
/
2
{\displaystyle 1/2}
.
The weight for the second column to the right of the point is
2
−
2
{\displaystyle 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
. And so on.
If you take the integer binary count of the first table, and reflect the digits about the binary point, you end up with the van der Corput sequence of numbers in base 2.
.0
.1
.01
.11
...
The third member of the sequence, binary 0.01, is therefore
0
×
2
−
1
+
1
×
2
−
2
{\displaystyle 0\times 2^{-1}+1\times 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
.
Distribution of 2500 points each: Van der Corput (top) vs pseudorandom
0
≤
x
<
1
{\displaystyle 0\leq x<1}
Monte Carlo simulations
This sequence is also a superset of the numbers representable by the "fraction" field of an old IEEE floating point standard. In that standard, the "fraction" field represented the fractional part of a binary number beginning with "1." e.g. 1.101001101.
Hint
A hint at a way to generate members of the sequence is to modify a routine used to change the base of an integer:
>>> def base10change(n, base):
digits = []
while n:
n,remainder = divmod(n, base)
digits.insert(0, remainder)
return digits
>>> base10change(11, 2)
[1, 0, 1, 1]
the above showing that 11 in decimal is
1
×
2
3
+
0
×
2
2
+
1
×
2
1
+
1
×
2
0
{\displaystyle 1\times 2^{3}+0\times 2^{2}+1\times 2^{1}+1\times 2^{0}}
.
Reflected this would become .1101 or
1
×
2
−
1
+
1
×
2
−
2
+
0
×
2
−
3
+
1
×
2
−
4
{\displaystyle 1\times 2^{-1}+1\times 2^{-2}+0\times 2^{-3}+1\times 2^{-4}}
Task description
Create a function/method/routine that given n, generates the n'th term of the van der Corput sequence in base 2.
Use the function to compute and display the first ten members of the sequence. (The first member of the sequence is for n=0).
As a stretch goal/extra credit, compute and show members of the sequence for bases other than 2.
See also
The Basic Low Discrepancy Sequences
Non-decimal radices/Convert
Van der Corput sequence
| #Haskell | Haskell | import Data.Ratio (Rational(..), (%), numerator, denominator)
import Data.List (unfoldr)
import Text.Printf (printf)
-- A wrapper type for Rationals to make them look nicer when we print them.
newtype Rat =
Rat Rational
instance Show Rat where
show (Rat n) = show (numerator n) <> ('/' : show (denominator n))
-- Convert a list of base b digits to its corresponding number.
-- We assume the digits are valid base b numbers and that
-- their order is from least to most significant.
digitsToNum :: Integer -> [Integer] -> Integer
digitsToNum b = foldr1 (\d acc -> b * acc + d)
-- Convert a number to the list of its base b digits.
-- The order will be from least to most significant.
numToDigits :: Integer -> Integer -> [Integer]
numToDigits _ 0 = [0]
numToDigits b n = unfoldr step n
where
step 0 = Nothing
step m =
let (q, r) = m `quotRem` b
in Just (r, q)
-- Return the n'th element in the base b van der Corput sequence.
-- The base must be ≥ 2.
vdc :: Integer -> Integer -> Rat
vdc b n
| b < 2 = error "vdc: base must be ≥ 2"
| otherwise =
let ds = reverse $ numToDigits b n
in Rat (digitsToNum b ds % b ^ length ds)
-- Each base followed by a specified range of van der Corput numbers.
printVdcRanges :: ([Integer], [Integer]) -> IO ()
printVdcRanges (bases, nums) =
mapM_
putStrLn
[ printf "Base %d:" b <> concatMap (printf " %5s" . show) rs
| b <- bases
, let rs = map (vdc b) nums ]
main :: IO ()
main = do
-- Small bases:
printVdcRanges ([2, 3, 4, 5], [0 .. 9])
putStrLn []
-- Base 123:
printVdcRanges ([123], [50,100 .. 300]) |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
The encoded string "google.com/search?q=%60Abdu%27l-Bah%C3%A1" should revert to the unencoded form "google.com/search?q=`Abdu'l-Bahá".
| #CoffeeScript | CoffeeScript |
console.log decodeURIComponent "http%3A%2F%2Ffoo%20bar%2F?name=Foo%20Barson"
|
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
The encoded string "google.com/search?q=%60Abdu%27l-Bah%C3%A1" should revert to the unencoded form "google.com/search?q=`Abdu'l-Bahá".
| #Common_Lisp | Common Lisp | (defun decode (string &key start)
(assert (char= (char string start) #\%))
(if (>= (length string) (+ start 3))
(multiple-value-bind (code pos)
(parse-integer string :start (1+ start) :end (+ start 3) :radix 16 :junk-allowed t)
(if (= pos (+ start 3))
(values (code-char code) pos)
(values #\% (1+ start))))
(values #\% (1+ start))))
(defun url-decode (url)
(loop with start = 0
for pos = (position #\% url :start start)
collect (subseq url start pos) into chunks
when pos
collect (multiple-value-bind (decoded next) (decode url :start pos)
(setf start next)
(string decoded))
into chunks
while pos
finally (return (apply #'concatenate 'string chunks))))
(url-decode "http%3A%2F%2Ffoo%20bar%2F") |
http://rosettacode.org/wiki/UPC | UPC | Goal
Convert UPC bar codes to decimal.
Specifically:
The UPC standard is actually a collection of standards -- physical standards, data format standards, product reference standards...
Here, in this task, we will focus on some of the data format standards, with an imaginary physical+electrical implementation which converts physical UPC bar codes to ASCII (with spaces and # characters representing the presence or absence of ink).
Sample input
Below, we have a representation of ten different UPC-A bar codes read by our imaginary bar code reader:
# # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # #
# # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # #
# # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # #
# # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # #
# # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # #
# # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # #
# # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # #
# # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # #
# # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # #
# # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # #
Some of these were entered upside down, and one entry has a timing error.
Task
Implement code to find the corresponding decimal representation of each, rejecting the error.
Extra credit for handling the rows entered upside down (the other option is to reject them).
Notes
Each digit is represented by 7 bits:
0: 0 0 0 1 1 0 1
1: 0 0 1 1 0 0 1
2: 0 0 1 0 0 1 1
3: 0 1 1 1 1 0 1
4: 0 1 0 0 0 1 1
5: 0 1 1 0 0 0 1
6: 0 1 0 1 1 1 1
7: 0 1 1 1 0 1 1
8: 0 1 1 0 1 1 1
9: 0 0 0 1 0 1 1
On the left hand side of the bar code a space represents a 0 and a # represents a 1.
On the right hand side of the bar code, a # represents a 0 and a space represents a 1
Alternatively (for the above): spaces always represent zeros and # characters always represent ones, but the representation is logically negated -- 1s and 0s are flipped -- on the right hand side of the bar code.
The UPC-A bar code structure
It begins with at least 9 spaces (which our imaginary bar code reader unfortunately doesn't always reproduce properly),
then has a # # sequence marking the start of the sequence,
then has the six "left hand" digits,
then has a # # sequence in the middle,
then has the six "right hand digits",
then has another # # (end sequence), and finally,
then ends with nine trailing spaces (which might be eaten by wiki edits, and in any event, were not quite captured correctly by our imaginary bar code reader).
Finally, the last digit is a checksum digit which may be used to help detect errors.
Verification
Multiply each digit in the represented 12 digit sequence by the corresponding number in (3,1,3,1,3,1,3,1,3,1,3,1) and add the products.
The sum (mod 10) must be 0 (must have a zero as its last digit) if the UPC number has been read correctly.
| #Action.21 | Action! | DEFINE PTR="CARD"
DEFINE RESOK="255"
DEFINE RESUPSIDEDOWN="254"
DEFINE RESINVALID="253"
DEFINE DIGITCOUNT="12"
DEFINE DIGITLEN="7"
PTR ARRAY ldigits(10),rdigits(10)
CHAR ARRAY marker="# #",midmarker=" # # "
PROC Init()
ldigits(0)=" ## #" ldigits(1)=" ## #"
ldigits(2)=" # ##" ldigits(3)=" #### #"
ldigits(4)=" # ##" ldigits(5)=" ## #"
ldigits(6)=" # ####" ldigits(7)=" ### ##"
ldigits(8)=" ## ###" ldigits(9)=" # ##"
rdigits(0)="### # " rdigits(1)="## ## "
rdigits(2)="## ## " rdigits(3)="# # "
rdigits(4)="# ### " rdigits(5)="# ### "
rdigits(6)="# # " rdigits(7)="# # "
rdigits(8)="# # " rdigits(9)="### # "
RETURN
BYTE FUNC DecodeMarker(CHAR ARRAY s BYTE POINTER pos CHAR ARRAY marker)
CHAR ARRAY tmp(6)
BYTE x
x=pos^+marker(0)
IF x>s(0) THEN
RETURN (RESINVALID)
ELSE
SCopyS(tmp,s,pos^,pos^+marker(0)-1)
pos^==+marker(0)
IF SCompare(tmp,marker)#0 THEN
RETURN (RESINVALID)
FI
FI
RETURN (RESOK)
BYTE FUNC DecodeDigit(CHAR ARRAY s BYTE POINTER pos PTR ARRAY digits)
CHAR ARRAY tmp(DIGITLEN+1)
BYTE i,x
x=pos^+DIGITLEN
IF x>s(0) THEN
RETURN (RESINVALID)
ELSE
SCopyS(tmp,s,pos^,pos^+DIGITLEN-1)
pos^==+DIGITLEN
FOR i=0 TO 9
DO
IF SCompare(tmp,digits(i))=0 THEN
RETURN (i)
FI
OD
FI
RETURN (RESINVALID)
BYTE FUNC Validation(BYTE ARRAY code)
BYTE ARRAY mult=[3 1 3 1 3 1 3 1 3 1 3 1]
BYTE i
INT sum
sum=0
FOR i=0 TO DIGITCOUNT-1
DO
sum==+code(i)*mult(i)
OD
IF sum MOD 10=0 THEN
RETURN (RESOK)
FI
RETURN (RESINVALID)
BYTE FUNC DecodeInternal(CHAR ARRAY s BYTE ARRAY code)
BYTE res,pos,i
pos=1
WHILE pos<=s(0) AND s(pos)=32
DO pos==+1 OD
res=DecodeMarker(s,@pos,marker)
IF res=RESINVALID THEN RETURN (res) FI
FOR i=0 TO 5
DO
res=DecodeDigit(s,@pos,ldigits)
IF res=RESINVALID THEN RETURN (res) FI
code(i)=res
OD
res=DecodeMarker(s,@pos,midmarker)
IF res=RESINVALID THEN RETURN (res) FI
FOR i=6 TO 11
DO
res=DecodeDigit(s,@pos,rdigits)
IF res=RESINVALID THEN RETURN (res) FI
code(i)=res
OD
res=DecodeMarker(s,@pos,marker)
IF res=RESINVALID THEN RETURN (res) FI
res=Validation(code)
RETURN (res)
PROC Reverse(CHAR ARRAY src,dst)
BYTE i,j
i=1 j=src(0) dst(0)=j
WHILE j>0
DO
dst(j)=src(i)
i==+1 j==-1
OD
RETURN
BYTE FUNC Decode(CHAR ARRAY s BYTE ARRAY code)
CHAR ARRAY tmp(256)
BYTE res
res=DecodeInternal(s,code)
IF res=RESOK THEN RETURN (res) FI
Reverse(s,tmp)
res=DecodeInternal(tmp,code)
IF res=RESINVALID THEN RETURN (res) FI
RETURN (RESUPSIDEDOWN)
PROC Test(BYTE id CHAR ARRAY s)
BYTE ARRAY code(DIGITCOUNT)
BYTE res,i
res=Decode(s,code)
IF id<10 THEN Put(32) FI
PrintF("%B: ",id)
IF res=RESINVALID THEN
PrintE("invalid")
ELSE
FOR i=0 TO DIGITCOUNT-1
DO
PrintB(code(i))
OD
IF res=RESUPSIDEDOWN THEN
PrintE(" valid (upside down)")
ELSE
PrintE(" valid")
FI
FI
RETURN
PROC Main()
PTR ARRAY codes(10)
BYTE i
Init()
codes(0)=" # # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # # "
codes(1)=" # # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # # "
codes(2)=" # # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # # "
codes(3)=" # # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # # "
codes(4)=" # # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # # "
codes(5)=" # # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # # "
codes(6)=" # # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # # "
codes(7)=" # # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # # "
codes(8)=" # # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # # "
codes(9)=" # # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # # "
FOR i=0 TO 9
DO
Test(i+1,codes(i))
OD
RETURN |
http://rosettacode.org/wiki/Update_a_configuration_file | Update a configuration file | We have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines begininning with a hash or a semicolon are ignored by the application
# program. Blank lines are also ignored by the application program.
# The first word on each non comment line is the configuration option.
# Remaining words or numbers on the line are configuration parameter
# data fields.
# Note that configuration option names are not case sensitive. However,
# configuration parameter data is case sensitive and the lettercase must
# be preserved.
# This is a favourite fruit
FAVOURITEFRUIT banana
# This is a boolean that should be set
NEEDSPEELING
# This boolean is commented out
; SEEDSREMOVED
# How many bananas we have
NUMBEROFBANANAS 48
The task is to manipulate the configuration file as follows:
Disable the needspeeling option (using a semicolon prefix)
Enable the seedsremoved option by removing the semicolon and any leading whitespace
Change the numberofbananas parameter to 1024
Enable (or create if it does not exist in the file) a parameter for numberofstrawberries with a value of 62000
Note that configuration option names are not case sensitive. This means that changes should be effected, regardless of the case.
Options should always be disabled by prefixing them with a semicolon.
Lines beginning with hash symbols should not be manipulated and left unchanged in the revised file.
If a configuration option does not exist within the file (in either enabled or disabled form), it should be added during this update. Duplicate configuration option names in the file should be removed, leaving just the first entry.
For the purpose of this task, the revised file should contain appropriate entries, whether enabled or not for needspeeling,seedsremoved,numberofbananas and numberofstrawberries.)
The update should rewrite configuration option names in capital letters. However lines beginning with hashes and any parameter data must not be altered (eg the banana for favourite fruit must not become capitalized). The update process should also replace double semicolon prefixes with just a single semicolon (unless it is uncommenting the option, in which case it should remove all leading semicolons).
Any lines beginning with a semicolon or groups of semicolons, but no following option should be removed, as should any leading or trailing whitespace on the lines. Whitespace between the option and parameters should consist only of a single
space, and any non-ASCII extended characters, tabs characters, or control codes
(other than end of line markers), should also be removed.
Related tasks
Read a configuration file
| #Erlang | Erlang |
-module( update_configuration_file ).
-export( [add/3, change/3, disable/2, enable/2, read/1, task/0, write/2] ).
add( Option, Value, Lines ) ->
Upper = string:to_upper( Option ),
[string:join( [Upper, Value], " " ) | Lines].
change( Option, Value, Lines ) ->
Upper = string:to_upper( Option ),
change_done( Option, Value, Lines, [change_option(Upper, Value, X) || X <- Lines] ).
disable( Option, Lines ) ->
Upper = string:to_upper( Option ),
[disable_option(Upper, X) || X <- Lines].
enable( Option, Lines ) ->
Upper = string:to_upper( Option ),
[enable_option(Upper, X) || X <- Lines].
read( Name ) ->
{ok, Binary} = file:read_file( Name ),
Lines = [binary:bin_to_list(X) || X <- binary:split( Binary, <<"\n">>, [global] )],
Lines_no_white = [string:strip(X) || X <- Lines],
Lines_no_control = [strip_control(X) || X <- Lines_no_white],
Lines_no_consecutive_space = [string:join(string:tokens(X, " "), " ") || X <- Lines_no_control],
Lines_no_consecutive_semicolon = [strip_semicolon(X) || X <- Lines_no_consecutive_space],
Lines_no_empty = lists:filter( fun strip_empty/1, Lines_no_consecutive_semicolon ),
Lines_upper = [to_upper(X) || X <- Lines_no_empty],
lists:reverse( lists:foldl(fun remove_duplicates/2, [], Lines_upper) ).
task() ->
Lines = read( "priv/configuration_file2" ),
Disabled_lines = disable( "needspeeling", Lines ),
Enabled_lines = enable( "SEEDSREMOVED", Disabled_lines ),
Changed_lines1 = change( "NUMBEROFBANANAS", "1024", Enabled_lines ),
Changed_lines2 = change( "numberofstrawberries", "62000", Changed_lines1 ),
write( "configuration_file", Changed_lines2 ),
[io:fwrite( "Wrote this line: ~s~n", [X]) || X <- Changed_lines2].
write( Name, Lines ) -> file:write_file( Name, binary:list_to_bin(string:join(Lines, "\n")) ).
change_done( Option, Value, Lines, Lines ) -> add( Option, Value, Lines );
change_done( _Option, _Value, _Lines, New_lines ) -> New_lines.
change_option( Option, Value, String ) -> change_option_same( string:str(String, Option), Value, String ).
change_option_same( 1, Value, String ) ->
[Option | _T] = string:tokens( String, " " ),
string:join( [Option, Value], " " );
change_option_same( _N, _Value, String ) -> String.
disable_option( Option, String ) -> disable_option_same( string:str(String, Option), String ).
disable_option_same( 1, String ) -> "; " ++ String;
disable_option_same( _N, String ) -> String.
enable_option( Option, String ) -> enable_option_same( string:str(String, "; " ++ Option), String ).
enable_option_same( 1, "; " ++ String ) -> String;
enable_option_same( _N, String ) -> String.
is_semicolon( $; ) -> true;
is_semicolon( _C ) -> false.
remove_duplicates( "#" ++_T=Line, Lines ) -> [Line | Lines];
remove_duplicates( Line, Lines ) ->
Duplicates = [X || X <-Lines, 1 =:= string:str(Line, X)],
remove_duplicates( Duplicates, Line, Lines ).
remove_duplicates( [], Line, Lines ) -> [Line | Lines];
remove_duplicates( _Duplicates, _Line, Lines ) -> Lines.
strip_control( "" ) -> "";
strip_control( ";" ++ _T=String ) -> lists:filter( fun strip_control_codes:is_not_control_code_nor_extended_character/1, String );
strip_control( String ) -> String.
strip_empty( ";" ) -> false;
strip_empty( _String ) -> true.
strip_semicolon( ";" ++ _T=String ) -> ";" ++ lists:dropwhile( fun is_semicolon/1, String );
strip_semicolon( String ) -> String.
to_upper( "" ) -> "";
to_upper( "#" ++ _T=String ) -> String;
to_upper( "; " ++ _T=String ) ->
[";", Option | T] = string:tokens( String, " " ),
string:join( [";", string:to_upper(Option) | T], " " );
to_upper( String ) ->
[Option | T] = string:tokens( String, " " ),
string:join( [string:to_upper(Option) | T], " " ).
|
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
| #C.23 | C# | using System;
namespace C_Sharp_Console {
class example {
static void Main() {
string word;
int num;
Console.Write("Enter an integer: ");
num = Console.Read();
Console.Write("Enter a String: ");
word = Console.ReadLine();
}
}
} |
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
| #C.2B.2B | C++ | #include <iostream>
#include <string>
using namespace std;
int main()
{
// while probably all current implementations have int wide enough for 75000, the C++ standard
// only guarantees this for long int.
long int integer_input;
string string_input;
cout << "Enter an integer: ";
cin >> integer_input;
cout << "Enter a string: ";
cin >> string_input;
return 0;
} |
http://rosettacode.org/wiki/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #Delphi | Delphi | program UserInputGraphical;
{$APPTYPE CONSOLE}
uses SysUtils, Dialogs;
var
s: string;
lStringValue: string;
lIntegerValue: Integer;
begin
lStringValue := InputBox('User input/Graphical', 'Enter a string', '');
repeat
s := InputBox('User input/Graphical', 'Enter the number 75000', '75000');
lIntegerValue := StrToIntDef(s, 0);
if lIntegerValue <> 75000 then
ShowMessage('Invalid entry: ' + s);
until lIntegerValue = 75000;
end. |
http://rosettacode.org/wiki/UTF-8_encode_and_decode | UTF-8 encode and decode | As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the UTF-8 encoding.
Then you have to write the corresponding decoder that takes a sequence of 1-4 UTF-8 encoded bytes and return the corresponding unicode character.
Demonstrate the functionality of your encoder and decoder on the following five characters:
Character Name Unicode UTF-8 encoding (hex)
---------------------------------------------------------------------------------
A LATIN CAPITAL LETTER A U+0041 41
ö LATIN SMALL LETTER O WITH DIAERESIS U+00F6 C3 B6
Ж CYRILLIC CAPITAL LETTER ZHE U+0416 D0 96
€ EURO SIGN U+20AC E2 82 AC
𝄞 MUSICAL SYMBOL G CLEF U+1D11E F0 9D 84 9E
Provided below is a reference implementation in Common Lisp.
| #F.23 | F# |
// Unicode character point to UTF8. Nigel Galloway: March 19th., 2018
let fN g = match List.findIndex (fun n->n>g) [0x80;0x800;0x10000;0x110000] with
|0->[g]
|1->[0xc0+(g&&&0x7c0>>>6);0x80+(g&&&0x3f)]
|2->[0xe0+(g&&&0xf000>>>12);0x80+(g&&&0xfc0>>>6);0x80+(g&&&0x3f)]
|_->[0xf0+(g&&&0x1c0000>>>18);0x80+(g&&&0x3f000>>>12);0x80+(g&&&0xfc0>>>6);0x80+(g&&&0x3f)]
|
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a 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.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (int argc, char * argv [])
{
char Buffer [1024];
size_t Size = sizeof (Buffer);
if (0 == Query (Buffer, &Size))
{
printf ("failed to call Query\n");
}
else
{
char * Ptr = Buffer;
while (Size-- > 0) putchar (*Ptr++);
putchar ('\n');
}
}
Implement the missing Query function in your language, and let this C program call it. The function should place the string Here am I into the buffer which is passed to it as the parameter Data. The buffer size in bytes is passed as the parameter Length. When there is no room in the buffer, Query shall return 0. Otherwise it overwrites the beginning of Buffer, sets the number of overwritten bytes into Length and returns 1.
| #Ol | Ol |
#include <extensions/embed.h>
#define min(x,y) (x < y ? x : y)
extern unsigned char repl[];
int Query(char *Data, size_t *Length) {
ol_t ol;
embed_new(&ol, repl, 0);
word s = embed_eval(&ol, new_string(&ol,
"(define sample \"Here am I\")"
"sample"
), 0);
if (!is_string(s))
goto fail;
int i = *Length = min(string_length(s), *Length);
memcpy(Data, string_value(s), i);
*Length = i;
OL_free(ol.vm);
return 1;
fail:
OL_free(ol.vm);
return 0;
}
|
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a 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.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (int argc, char * argv [])
{
char Buffer [1024];
size_t Size = sizeof (Buffer);
if (0 == Query (Buffer, &Size))
{
printf ("failed to call Query\n");
}
else
{
char * Ptr = Buffer;
while (Size-- > 0) putchar (*Ptr++);
putchar ('\n');
}
}
Implement the missing Query function in your language, and let this C program call it. The function should place the string Here am I into the buffer which is passed to it as the parameter Data. The buffer size in bytes is passed as the parameter Length. When there is no room in the buffer, Query shall return 0. Otherwise it overwrites the beginning of Buffer, sets the number of overwritten bytes into Length and returns 1.
| #PARI.2FGP | PARI/GP | Strchr(Vecsmall(apply(k->if(k>96&&k<123,(k-84)%26+97,if(k>64&&k<91,(k-52)%26+65,k)),Vec(Vecsmall(s))))) |
http://rosettacode.org/wiki/URL_parser | URL parser | URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
According to the standards, the characters:
! * ' ( ) ; : @ & = + $ , / ? % # [ ]
only need to be percent-encoded (%) in case of possible confusion.
Also note that the path, query and fragment are case sensitive, even if the scheme and domain are not.
The way the returned information is provided (set of variables, array, structured, record, object,...)
is language-dependent and left to the programmer, but the code should be clear enough to reuse.
Extra credit is given for clear error diagnostics.
Here is the official standard: https://tools.ietf.org/html/rfc3986,
and here is a simpler BNF: http://www.w3.org/Addressing/URL/5_URI_BNF.html.
Test cases
According to T. Berners-Lee
foo://example.com:8042/over/there?name=ferret#nose should parse into:
scheme = foo
domain = example.com
port = :8042
path = over/there
query = name=ferret
fragment = nose
urn:example:animal:ferret:nose should parse into:
scheme = urn
path = example:animal:ferret:nose
other URLs that must be parsed include:
jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true
ftp://ftp.is.co.za/rfc/rfc1808.txt
http://www.ietf.org/rfc/rfc2396.txt#header1
ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two
mailto:[email protected]
news:comp.infosystems.www.servers.unix
tel:+1-816-555-1212
telnet://192.0.2.16:80/
urn:oasis:names:specification:docbook:dtd:xml:4.1.2
| #Lua | Lua | local url = require('socket.url')
local tests = {
'foo://example.com:8042/over/there?name=ferret#nose',
'urn:example:animal:ferret:nose',
'jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true',
'ftp://ftp.is.co.za/rfc/rfc1808.txt',
'http://www.ietf.org/rfc/rfc2396.txt#header1',
'ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two',
'mailto:[email protected]',
'news:comp.infosystems.www.servers.unix',
'tel:+1-816-555-1212',
'telnet://192.0.2.16:80/',
'urn:oasis:names:specification:docbook:dtd:xml:4.1.2'
}
for _, test in ipairs(tests) do
local parsed = url.parse(test)
io.write('URI: ' .. test .. '\n')
for k, v in pairs(parsed) do
io.write(string.format(' %s: %s\n', k, v))
end
io.write('\n')
end
|
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #F.23 | F# | open System
[<EntryPoint>]
let main args =
printfn "%s" (Uri.EscapeDataString(args.[0]))
0 |
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #Factor | Factor | USING: combinators.short-circuit unicode urls.encoding.private ;
: my-url-encode ( str -- encoded )
[ { [ alpha? ] [ "-._~" member? ] } 1|| ] (url-encode) ;
"http://foo bar/" my-url-encode print |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #DWScript | DWScript |
var i := 123; // inferred type of i is Integer
var s := 'abc'; // inferred type of s is String
var o := TObject.Create; // inferred type of o is TObject
var s2 := o.ClassName; // inferred type of s2 is String as that's the type returned by ClassName
|
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #Dyalect | Dyalect | //A constant declaration
let pi = 3.14
private {
//private constant, not visible outside of a module
let privateConst = 3.3
}
//Variable declaration
var x = 42
//Assignment
x = 42.42
//Dyalect is a dynamic language, so types are attached
//to values, not to the names
var foo = (x: 2, y: 4) //foo is of type Tuple
var bar = "Hello!" //bar is of type String
//Global variable
var g = 1.1
{
//local variable (not visible outside of { } brackets)
var loc = 2.2
}
func fun() {
//Local variables, not visible outside of function
var x = 1
var y = 2
}
func parent() {
//A local variable inside a parent function
var x = 1
func child() {
//A local variable inside a nested function
//It shadows a parent's variable
var x = 2
//But this is how we can reference a variable from
//a parent function
base.x
}
} |
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 A:
0
Using B:
0 0
Using C:
0 0 1
Using B:
0 0 1 0
Using C: (zero last occurred two steps back - before the one)
0 0 1 0 2
Using B:
0 0 1 0 2 0
Using C: (two last occurred two steps back - before the zero)
0 0 1 0 2 0 2 2
Using C: (two last occurred one step back)
0 0 1 0 2 0 2 2 1
Using C: (one last appeared six steps back)
0 0 1 0 2 0 2 2 1 6
...
Task
Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
Use it to display here, on this page:
The first ten terms of the sequence.
Terms 991 - to - 1000 of the sequence.
References
Don't Know (the Van Eck Sequence) - Numberphile video.
Wikipedia Article: Van Eck's Sequence.
OEIS sequence: A181391.
| #J | J | VanEck=. (, (<:@:# - }: i: {:))^:(]`0:) |
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 A:
0
Using B:
0 0
Using C:
0 0 1
Using B:
0 0 1 0
Using C: (zero last occurred two steps back - before the one)
0 0 1 0 2
Using B:
0 0 1 0 2 0
Using C: (two last occurred two steps back - before the zero)
0 0 1 0 2 0 2 2
Using C: (two last occurred one step back)
0 0 1 0 2 0 2 2 1
Using C: (one last appeared six steps back)
0 0 1 0 2 0 2 2 1 6
...
Task
Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
Use it to display here, on this page:
The first ten terms of the sequence.
Terms 991 - to - 1000 of the sequence.
References
Don't Know (the Van Eck Sequence) - Numberphile video.
Wikipedia Article: Van Eck's Sequence.
OEIS sequence: A181391.
| #Java | Java |
import java.util.HashMap;
import java.util.Map;
public class VanEckSequence {
public static void main(String[] args) {
System.out.println("First 10 terms of Van Eck's sequence:");
vanEck(1, 10);
System.out.println("");
System.out.println("Terms 991 to 1000 of Van Eck's sequence:");
vanEck(991, 1000);
}
private static void vanEck(int firstIndex, int lastIndex) {
Map<Integer,Integer> vanEckMap = new HashMap<>();
int last = 0;
if ( firstIndex == 1 ) {
System.out.printf("VanEck[%d] = %d%n", 1, 0);
}
for ( int n = 2 ; n <= lastIndex ; n++ ) {
int vanEck = vanEckMap.containsKey(last) ? n - vanEckMap.get(last) : 0;
vanEckMap.put(last, n);
last = vanEck;
if ( n >= firstIndex ) {
System.out.printf("VanEck[%d] = %d%n", n, vanEck);
}
}
}
}
|
http://rosettacode.org/wiki/Vampire_number | Vampire number | A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
together they consist of exactly the same decimal digits as the original number
at most one of them has a trailing zero
An example of a vampire number and its fangs: 1260 : (21, 60)
Task
Print the first 25 vampire numbers and their fangs.
Check if the following numbers are vampire numbers and, if so, print them and their fangs:
16758243290880, 24959017348650, 14593825548650
Note that a vampire number can have more than one pair of fangs.
See also
numberphile.com.
vampire search algorithm
vampire numbers on OEIS
| #Phix | Phix | with javascript_semantics
requires("1.0.2") -- (for in)
function vampire(atom v)
sequence res = {}
if v>=0 then
string vs = sprintf("%d",v)
if mod(length(vs),2)=0 then -- even length
vs = sort(vs)
for i=power(10,length(vs)/2-1) to floor(sqrt(v)) do
if remainder(v,i)=0 then
integer i2 = v/i
string si = sprintf("%d",i),
s2 = sprintf("%d",i2)
if (si[$]!='0' or s2[$]!='0')
and sort(si&s2)=vs then
res = append(res,{i,i2})
end if
end if
end for
end if
end if
return res
end function
integer found = 0
atom i = 0
sequence res
puts(1,"The first 26 vampire numbers and their fangs:\n")
while found<26 do
res = vampire(i)
if length(res) then
found += 1
printf(1,"%d: %d: %v\n",{found,i,res})
end if
i += 1
end while
puts(1,"\n")
for i in {16758243290880,24959017348650,14593825548650} do
res = vampire(i)
printf(1,"%d: %s\n",{i,iff(res={}?"not a vampire number":sprint(res))})
end for
|
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #M4 | M4 | define(`showN',
`ifelse($1,0,`',`$2
$0(decr($1),shift(shift($@)))')')dnl
define(`showargs',`showN($#,$@)')dnl
dnl
showargs(a,b,c)
dnl
define(`x',`1,2')
define(`y',`,3,4,5')
showargs(x`'y) |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | ShowMultiArg[x___] := Do[Print[i], {i, {x}}] |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #MATLAB | MATLAB | function variadicFunction(varargin)
for i = (1:numel(varargin))
disp(varargin{i});
end
end |
http://rosettacode.org/wiki/Vector | Vector | Task
Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented.
The Vector may be initialized in any reasonable way.
Start and end points, and direction
Angular coefficient and value (length)
The four operations to be implemented are:
Vector + Vector addition
Vector - Vector subtraction
Vector * scalar multiplication
Vector / scalar division
| #Sidef | Sidef | class MyVector(:args) {
has Number x
has Number y
method init {
if ([:x, :y] ~~ args) {
x = args{:x}
y = args{:y}
}
elsif ([:length, :angle] ~~ args) {
x = args{:length}*args{:angle}.cos
y = args{:length}*args{:angle}.sin
}
elsif ([:from, :to] ~~ args) {
x = args{:to}[0]-args{:from}[0]
y = args{:to}[1]-args{:from}[1]
}
else {
die "Invalid arguments: #{args}"
}
}
method length { hypot(x, y) }
method angle { atan2(y, x) }
method +(MyVector v) { MyVector(x => x + v.x, y => y + v.y) }
method -(MyVector v) { MyVector(x => x - v.x, y => y - v.y) }
method *(Number n) { MyVector(x => x * n, y => y * n) }
method /(Number n) { MyVector(x => x / n, y => y / n) }
method neg { self * -1 }
method to_s { "vec[#{x}, #{y}]" }
}
var u = MyVector(x => 3, y => 4)
var v = MyVector(from => [1, 0], to => [2, 3])
var w = MyVector(length => 1, angle => 45.deg2rad)
say u #: vec[3, 4]
say v #: vec[1, 3]
say w #: vec[0.70710678118654752440084436210485, 0.70710678118654752440084436210485]
say u.length #: 5
say u.angle.rad2deg #: 53.13010235415597870314438744090659
say u+v #: vec[4, 7]
say u-v #: vec[2, 1]
say -u #: vec[-3, -4]
say u*10 #: vec[30, 40]
say u/2 #: vec[1.5, 2] |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar cipher
Rot-13
Substitution Cipher
| #Seed7 | Seed7 | $ include "seed7_05.s7i";
const func string: vigenereCipher (in string: source, in var string: keyword) is func
result
var string: dest is "";
local
var char: ch is ' ';
var integer: index is 1;
var integer: shift is 0;
begin
keyword := upper(keyword);
for ch range source do
if ch in {'A' .. 'Z'} | {'a' .. 'z'} then
shift := ord(keyword[succ(pred(index) rem length(keyword))]) - ord('A');
dest &:= chr(ord('A') + (ord(upper(ch)) - ord('A') + shift) rem 26);
incr(index);
end if;
end for;
end func;
const func string: vigenereDecipher (in string: source, in var string: keyword) is func
result
var string: dest is "";
local
var char: ch is ' ';
var integer: index is 0;
var integer: shift is 0;
begin
keyword := upper(keyword);
for ch key index range source do
if ch in {'A' .. 'Z'} | {'a' .. 'z'} then
shift := ord(keyword[succ(pred(index) rem length(keyword))]) - ord('A');
dest &:= chr(ord('A') + (ord(upper(ch)) - ord('A') - shift) mod 26);
end if;
end for;
end func;
const proc: main is func
local
const string: input is "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!";
const string: keyword is "VIGENERECIPHER";
var string: encrypted is "";
var string: decrypted is "";
begin
writeln("Input: " <& input);
writeln("key: " <& keyword);
encrypted := vigenereCipher(input, keyword);
writeln("Encrypted: " <& encrypted);
decrypted := vigenereDecipher(encrypted, keyword);
writeln("Decrypted: " <& decrypted);
end func; |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar cipher
Rot-13
Substitution Cipher
| #Sidef | Sidef | func s2v(s) { s.uc.scan(/[A-Z]/).map{.ord} »-» 65 }
func v2s(v) { v »%» 26 »+» 65 -> map{.chr}.join }
func blacken (red, key) { v2s(s2v(red) »+« s2v(key)) }
func redden (blk, key) { v2s(s2v(blk) »-« s2v(key)) }
var red = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!"
var key = "Vigenere Cipher!!!"
say red
say (var black = blacken(red, key))
say redden(black, key) |
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #Euphoria | Euphoria | constant X = 1, Y = 2, Z = 3
function dot_product(sequence a, sequence b)
return a[X]*b[X] + a[Y]*b[Y] + a[Z]*b[Z]
end function
function cross_product(sequence a, sequence b)
return { a[Y]*b[Z] - a[Z]*b[Y],
a[Z]*b[X] - a[X]*b[Z],
a[X]*b[Y] - a[Y]*b[X] }
end function
function scalar_triple(sequence a, sequence b, sequence c)
return dot_product( a, cross_product( b, c ) )
end function
function vector_triple( sequence a, sequence b, sequence c)
return cross_product( a, cross_product( b, c ) )
end function
constant a = { 3, 4, 5 }, b = { 4, 3, 5 }, c = { -5, -12, -13 }
puts(1,"a = ")
? a
puts(1,"b = ")
? b
puts(1,"c = ")
? c
puts(1,"a dot b = ")
? dot_product( a, b )
puts(1,"a x b = ")
? cross_product( a, b )
puts(1,"a dot (b x c) = ")
? scalar_triple( a, b, c )
puts(1,"a x (b x c) = ")
? vector_triple( a, b, c ) |
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded checksum is correct.
Demonstrate that your code passes the test-cases listed below.
Details
The format of an ISIN is as follows:
┌───────────── a 2-character ISO country code (A-Z)
│ ┌─────────── a 9-character security code (A-Z, 0-9)
│ │ ┌── a checksum digit (0-9)
AU0000XVGZA3
For this task, you may assume that any 2-character alphabetic sequence is a valid country code.
The checksum can be validated as follows:
Replace letters with digits, by converting each character from base 36 to base 10, e.g. AU0000XVGZA3 →1030000033311635103.
Perform the Luhn test on this base-10 number.
There is a separate task for this test: Luhn test of credit card numbers.
You don't have to replicate the implementation of this test here ─── you can just call the existing function from that task. (Add a comment stating if you did this.)
Test cases
ISIN
Validity
Comment
US0378331005
valid
US0373831005
not valid
The transposition typo is caught by the checksum constraint.
U50378331005
not valid
The substitution typo is caught by the format constraint.
US03378331005
not valid
The duplication typo is caught by the format constraint.
AU0000XVGZA3
valid
AU0000VXGZA3
valid
Unfortunately, not all transposition typos are caught by the checksum constraint.
FR0000988040
valid
(The comments are just informational. Your function should simply return a Boolean result. See #Raku for a reference solution.)
Related task:
Luhn test of credit card numbers
Also see
Interactive online ISIN validator
Wikipedia article: International Securities Identification Number
| #langur | langur | val .luhntest = f(.s) {
val .t = [0, 2, 4, 6, 8, 1, 3, 5, 7, 9]
val .numbers = s2n .s
val .oddeven = len(.numbers) rem 2
for[=0] .i of .numbers {
_for += if(.i rem 2 == .oddeven: .numbers[.i]; .t[.numbers[.i]+1])
} div 10
}
val .isintest = f(.s) {
matching(re/^[A-Z][A-Z][0-9A-Z]{9}[0-9]$/, .s) and
.luhntest(join s2n .s)
}
val .tests = h{
"US0378331005": true,
"US0373831005": false,
"U50378331005": false,
"AU0000XVGZA3": true,
"AU0000VXGZA3": true,
"FR0000988040": true,
"US03378331005": false,
}
for .key in sort(keys .tests) {
val .pass = .isintest(.key)
write .key, ": ", .pass
writeln if(.pass == .tests[.key]: ""; " (ISIN TEST FAILED)")
} |
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded checksum is correct.
Demonstrate that your code passes the test-cases listed below.
Details
The format of an ISIN is as follows:
┌───────────── a 2-character ISO country code (A-Z)
│ ┌─────────── a 9-character security code (A-Z, 0-9)
│ │ ┌── a checksum digit (0-9)
AU0000XVGZA3
For this task, you may assume that any 2-character alphabetic sequence is a valid country code.
The checksum can be validated as follows:
Replace letters with digits, by converting each character from base 36 to base 10, e.g. AU0000XVGZA3 →1030000033311635103.
Perform the Luhn test on this base-10 number.
There is a separate task for this test: Luhn test of credit card numbers.
You don't have to replicate the implementation of this test here ─── you can just call the existing function from that task. (Add a comment stating if you did this.)
Test cases
ISIN
Validity
Comment
US0378331005
valid
US0373831005
not valid
The transposition typo is caught by the checksum constraint.
U50378331005
not valid
The substitution typo is caught by the format constraint.
US03378331005
not valid
The duplication typo is caught by the format constraint.
AU0000XVGZA3
valid
AU0000VXGZA3
valid
Unfortunately, not all transposition typos are caught by the checksum constraint.
FR0000988040
valid
(The comments are just informational. Your function should simply return a Boolean result. See #Raku for a reference solution.)
Related task:
Luhn test of credit card numbers
Also see
Interactive online ISIN validator
Wikipedia article: International Securities Identification Number
| #Lua | Lua | function luhn (n)
local revStr, s1, s2, digit, mod = n:reverse(), 0, 0
for pos = 1, #revStr do
digit = tonumber(revStr:sub(pos, pos))
if pos % 2 == 1 then
s1 = s1 + digit
else
digit = digit * 2
if digit > 9 then
mod = digit % 10
digit = mod + ((digit - mod) / 10)
end
s2 = s2 + digit
end
end
return (s1 + s2) % 10 == 0
end
function checkISIN (inStr)
if #inStr ~= 12 then return false end
local numStr = ""
for pos = 1, #inStr do
numStr = numStr .. tonumber(inStr:sub(pos, pos), 36)
end
return luhn(numStr)
end
local testCases = {
"US0378331005",
"US0373831005",
"US0373831005",
"US03378331005",
"AU0000XVGZA3",
"AU0000VXGZA3",
"FR0000988040"
}
for _, ISIN in pairs(testCases) do print(ISIN, checkISIN(ISIN)) end |
http://rosettacode.org/wiki/Van_der_Corput_sequence | Van der Corput sequence | When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of
2
0
{\displaystyle 2^{0}}
; the digit in the next column to the left has a multiplier of
2
1
{\displaystyle 2^{1}}
; and so on.
So in the following table:
0.
1.
10.
11.
...
the binary number "10" is
1
×
2
1
+
0
×
2
0
{\displaystyle 1\times 2^{1}+0\times 2^{0}}
.
You can also have binary digits to the right of the “point”, just as in the decimal number system. In that case, the digit in the place immediately to the right of the point has a weight of
2
−
1
{\displaystyle 2^{-1}}
, or
1
/
2
{\displaystyle 1/2}
.
The weight for the second column to the right of the point is
2
−
2
{\displaystyle 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
. And so on.
If you take the integer binary count of the first table, and reflect the digits about the binary point, you end up with the van der Corput sequence of numbers in base 2.
.0
.1
.01
.11
...
The third member of the sequence, binary 0.01, is therefore
0
×
2
−
1
+
1
×
2
−
2
{\displaystyle 0\times 2^{-1}+1\times 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
.
Distribution of 2500 points each: Van der Corput (top) vs pseudorandom
0
≤
x
<
1
{\displaystyle 0\leq x<1}
Monte Carlo simulations
This sequence is also a superset of the numbers representable by the "fraction" field of an old IEEE floating point standard. In that standard, the "fraction" field represented the fractional part of a binary number beginning with "1." e.g. 1.101001101.
Hint
A hint at a way to generate members of the sequence is to modify a routine used to change the base of an integer:
>>> def base10change(n, base):
digits = []
while n:
n,remainder = divmod(n, base)
digits.insert(0, remainder)
return digits
>>> base10change(11, 2)
[1, 0, 1, 1]
the above showing that 11 in decimal is
1
×
2
3
+
0
×
2
2
+
1
×
2
1
+
1
×
2
0
{\displaystyle 1\times 2^{3}+0\times 2^{2}+1\times 2^{1}+1\times 2^{0}}
.
Reflected this would become .1101 or
1
×
2
−
1
+
1
×
2
−
2
+
0
×
2
−
3
+
1
×
2
−
4
{\displaystyle 1\times 2^{-1}+1\times 2^{-2}+0\times 2^{-3}+1\times 2^{-4}}
Task description
Create a function/method/routine that given n, generates the n'th term of the van der Corput sequence in base 2.
Use the function to compute and display the first ten members of the sequence. (The first member of the sequence is for n=0).
As a stretch goal/extra credit, compute and show members of the sequence for bases other than 2.
See also
The Basic Low Discrepancy Sequences
Non-decimal radices/Convert
Van der Corput sequence
| #Icon_and_Unicon | Icon and Unicon | procedure main(A)
base := integer(get(A)) | 2
every writes(round(vdc(0 to 9,base),10)," ")
write()
end
procedure vdc(n, base)
e := 1.0
x := 0.0
while x +:= 1(((0 < n) % base) / (e *:= base), n /:= base)
return x
end
procedure round(n,d)
places := 10 ^ d
return real(integer(n*places + 0.5)) / places
end |
http://rosettacode.org/wiki/Van_der_Corput_sequence | Van der Corput sequence | When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of
2
0
{\displaystyle 2^{0}}
; the digit in the next column to the left has a multiplier of
2
1
{\displaystyle 2^{1}}
; and so on.
So in the following table:
0.
1.
10.
11.
...
the binary number "10" is
1
×
2
1
+
0
×
2
0
{\displaystyle 1\times 2^{1}+0\times 2^{0}}
.
You can also have binary digits to the right of the “point”, just as in the decimal number system. In that case, the digit in the place immediately to the right of the point has a weight of
2
−
1
{\displaystyle 2^{-1}}
, or
1
/
2
{\displaystyle 1/2}
.
The weight for the second column to the right of the point is
2
−
2
{\displaystyle 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
. And so on.
If you take the integer binary count of the first table, and reflect the digits about the binary point, you end up with the van der Corput sequence of numbers in base 2.
.0
.1
.01
.11
...
The third member of the sequence, binary 0.01, is therefore
0
×
2
−
1
+
1
×
2
−
2
{\displaystyle 0\times 2^{-1}+1\times 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
.
Distribution of 2500 points each: Van der Corput (top) vs pseudorandom
0
≤
x
<
1
{\displaystyle 0\leq x<1}
Monte Carlo simulations
This sequence is also a superset of the numbers representable by the "fraction" field of an old IEEE floating point standard. In that standard, the "fraction" field represented the fractional part of a binary number beginning with "1." e.g. 1.101001101.
Hint
A hint at a way to generate members of the sequence is to modify a routine used to change the base of an integer:
>>> def base10change(n, base):
digits = []
while n:
n,remainder = divmod(n, base)
digits.insert(0, remainder)
return digits
>>> base10change(11, 2)
[1, 0, 1, 1]
the above showing that 11 in decimal is
1
×
2
3
+
0
×
2
2
+
1
×
2
1
+
1
×
2
0
{\displaystyle 1\times 2^{3}+0\times 2^{2}+1\times 2^{1}+1\times 2^{0}}
.
Reflected this would become .1101 or
1
×
2
−
1
+
1
×
2
−
2
+
0
×
2
−
3
+
1
×
2
−
4
{\displaystyle 1\times 2^{-1}+1\times 2^{-2}+0\times 2^{-3}+1\times 2^{-4}}
Task description
Create a function/method/routine that given n, generates the n'th term of the van der Corput sequence in base 2.
Use the function to compute and display the first ten members of the sequence. (The first member of the sequence is for n=0).
As a stretch goal/extra credit, compute and show members of the sequence for bases other than 2.
See also
The Basic Low Discrepancy Sequences
Non-decimal radices/Convert
Van der Corput sequence
| #J | J | vdc=: ([ %~ %@[ #. #.inv)"0 _ |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
The encoded string "google.com/search?q=%60Abdu%27l-Bah%C3%A1" should revert to the unencoded form "google.com/search?q=`Abdu'l-Bahá".
| #Crystal | Crystal | require "uri"
puts URI.decode "http%3A%2F%2Ffoo%20bar%2F"
puts URI.decode "google.com/search?q=%60Abdu%27l-Bah%C3%A1" |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
The encoded string "google.com/search?q=%60Abdu%27l-Bah%C3%A1" should revert to the unencoded form "google.com/search?q=`Abdu'l-Bahá".
| #D | D | import std.stdio, std.uri;
void main() {
writeln(decodeComponent("http%3A%2F%2Ffoo%20bar%2F"));
} |
http://rosettacode.org/wiki/UPC | UPC | Goal
Convert UPC bar codes to decimal.
Specifically:
The UPC standard is actually a collection of standards -- physical standards, data format standards, product reference standards...
Here, in this task, we will focus on some of the data format standards, with an imaginary physical+electrical implementation which converts physical UPC bar codes to ASCII (with spaces and # characters representing the presence or absence of ink).
Sample input
Below, we have a representation of ten different UPC-A bar codes read by our imaginary bar code reader:
# # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # #
# # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # #
# # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # #
# # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # #
# # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # #
# # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # #
# # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # #
# # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # #
# # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # #
# # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # #
Some of these were entered upside down, and one entry has a timing error.
Task
Implement code to find the corresponding decimal representation of each, rejecting the error.
Extra credit for handling the rows entered upside down (the other option is to reject them).
Notes
Each digit is represented by 7 bits:
0: 0 0 0 1 1 0 1
1: 0 0 1 1 0 0 1
2: 0 0 1 0 0 1 1
3: 0 1 1 1 1 0 1
4: 0 1 0 0 0 1 1
5: 0 1 1 0 0 0 1
6: 0 1 0 1 1 1 1
7: 0 1 1 1 0 1 1
8: 0 1 1 0 1 1 1
9: 0 0 0 1 0 1 1
On the left hand side of the bar code a space represents a 0 and a # represents a 1.
On the right hand side of the bar code, a # represents a 0 and a space represents a 1
Alternatively (for the above): spaces always represent zeros and # characters always represent ones, but the representation is logically negated -- 1s and 0s are flipped -- on the right hand side of the bar code.
The UPC-A bar code structure
It begins with at least 9 spaces (which our imaginary bar code reader unfortunately doesn't always reproduce properly),
then has a # # sequence marking the start of the sequence,
then has the six "left hand" digits,
then has a # # sequence in the middle,
then has the six "right hand digits",
then has another # # (end sequence), and finally,
then ends with nine trailing spaces (which might be eaten by wiki edits, and in any event, were not quite captured correctly by our imaginary bar code reader).
Finally, the last digit is a checksum digit which may be used to help detect errors.
Verification
Multiply each digit in the represented 12 digit sequence by the corresponding number in (3,1,3,1,3,1,3,1,3,1,3,1) and add the products.
The sum (mod 10) must be 0 (must have a zero as its last digit) if the UPC number has been read correctly.
| #ALGOL_68 | ALGOL 68 | BEGIN
# number of digits encoded by UPC #
INT upc digits = 12;
# MODE to hold UPC bar code parse results #
MODE UPC = STRUCT( BOOL valid # TRUE if the UPC was valid, #
# FASLE otherwise #
, [ 1 : upc digits ]INT digits
# the digits encoded by the #
# UPC if it was valid #
, BOOL inverted # TRUE if the code was scanned #
# upside down, FALSE if it was #
# right-side up #
, STRING error message # erro rmessage if the string #
# was invalid #
);
# parses the UPC string s and returns a UPC containing the results #
PROC parse upc = ( STRING s )UPC:
BEGIN
# returns TRUE if we are at the end of s, FALSE otherwise #
PROC at end = BOOL: s pos > UPB s;
# counts and skips spaces in s #
PROC skip spaces = INT:
BEGIN
INT spaces := 0;
WHILE IF at end THEN FALSE ELSE s[ s pos ] = " " FI DO
spaces +:= 1;
s pos +:= 1
OD;
spaces
END; # skip spaces #
# skips over the next number of bits characters of s and returns #
# a bit representation ( space = 0, anything else = 1 ) #
PROC get value = ( INT number of bits )BITS:
BEGIN
BITS value := 2r0;
FOR b TO number of bits WHILE NOT at end DO
value := ( value SHL 1 ) OR IF s[ s pos ] = " " THEN 2r0 ELSE 2r1 FI;
s pos +:= 1
OD;
value
END; # get value #
# the representations of the digits #
[]BITS representations = ( 2r 0 0 0 1 1 0 1 # 0 #
, 2r 0 0 1 1 0 0 1 # 1 #
, 2r 0 0 1 0 0 1 1 # 2 #
, 2r 0 1 1 1 1 0 1 # 3 #
, 2r 0 1 0 0 0 1 1 # 4 #
, 2r 0 1 1 0 0 0 1 # 5 #
, 2r 0 1 0 1 1 1 1 # 6 #
, 2r 0 1 1 1 0 1 1 # 7 #
, 2r 0 1 1 0 1 1 1 # 8 #
, 2r 0 0 0 1 0 1 1 # 9 #
);
[]BITS reversed digits = ( 2r 0 1 0 0 1 1 1 # 0 #
, 2r 0 1 1 0 0 1 1 # 1 #
, 2r 0 0 1 1 0 1 1 # 2 #
, 2r 0 1 0 0 0 0 1 # 3 #
, 2r 0 0 1 1 1 0 1 # 4 #
, 2r 0 1 1 1 0 0 1 # 5 #
, 2r 0 0 0 0 1 0 1 # 6 #
, 2r 0 0 1 0 0 0 1 # 7 #
, 2r 0 0 0 1 0 0 1 # 8 #
, 2r 0 0 1 0 1 1 1 # 9 #
);
# number of digits in the left and right sides of the UPC #
INT digits per side = upc digits OVER 2;
UPC result;
FOR d TO upc digits DO ( digits OF result )[ d ] := 0 OD;
inverted OF result := FALSE;
error message OF result := "unknown error";
valid OF result := FALSE;
INT s pos := LWB s;
IF skip spaces < 6 # should be 9 but we are being tolerant #
THEN
# insufficient leading spaces #
error message OF result := "missing leading spaces"
ELIF get value( 3 ) /= 2r101 THEN
# no start #
error message OF result := "missing start sequence"
ELSE
# ok so far - should now have six digits, each encoded in #
# seven bits #
# note we store the digits as 1..10 if the are right-sid up #
# and -1..-10 if they are inverted, so we can distinguish #
# right-side up 0 and inverted 0 #
# the digits are corrected to be 0..9 later #
BOOL valid digits := TRUE;
FOR d TO digits per side WHILE valid digits DO
BITS code = get value( 7 );
BOOL found digit := FALSE;
FOR d pos TO UPB representations WHILE NOT found digit DO
IF code = representations[ d pos ] THEN
# found a "normal" digit #
found digit := TRUE;
( digits OF result )[ d ] := d pos
ELIF code = reversed digits[ d pos ] THEN
# found a reversed digit #
found digit := TRUE;
inverted OF result := TRUE;
( digits OF result )[ d ] := - d pos
FI
OD;
IF NOT found digit THEN
# have an invalid digit #
error message OF result := "invalid digit " + whole( d, 0 );
valid digits := FALSE
FI
OD;
IF NOT valid digits THEN
# had an error #
SKIP
ELIF get value( 5 ) /= 2r01010 THEN
# no middle separator #
error message OF result := "missing middle sequence"
ELSE
# should now have 6 negated digits #
FOR d FROM digits per side + 1 TO upc digits WHILE valid digits DO
BITS code = NOT get value( 7 ) AND 16r7f;
BOOL found digit := FALSE;
FOR d pos TO UPB representations WHILE NOT found digit DO
IF code = representations[ d pos ] THEN
# found a normal negated digit #
found digit := TRUE;
( digits OF result )[ d ] := d pos
ELIF code = reversed digits[ d pos ] THEN
# found reversed negated digit #
found digit := TRUE;
inverted OF result := TRUE;
( digits OF result )[ d ] := - d pos
FI
OD;
IF NOT found digit THEN
# have an invalid digit #
error message OF result := "invalid digit " + whole( d, 0 );
valid digits := FALSE
FI
OD;
IF NOT valid digits THEN
# had an error #
SKIP
ELIF get value( 3 ) /= 2r101 THEN
# no end sequence #
error message OF result := "missing end sequence"
ELIF skip spaces < 6 # should be 9 but we are being #
# tolerant #
THEN
# insufficient trailing spaces #
error message OF result := "insufficient trailing spaces"
ELIF NOT at end THEN
# extraneous stuff after the trailing spaces #
error message OF result := "unexpected trailing bits"
ELSE
# valid so far - if there were reversed digits, #
# check they were all reversed #
# and correct the digits to be in 0..9 #
BOOL all reversed := TRUE;
FOR d TO upc digits DO
IF ( digits OF result )[ d ] < 0 THEN
# reversd digit #
( digits OF result )[ d ] := ABS ( digits OF result )[ d ] - 1
ELSE
# normal digit #
( digits OF result )[ d ] -:= 1;
all reversed := FALSE
FI
OD;
IF inverted OF result AND NOT all reversed
THEN
# had a mixture of inverted and non-inverted #
# digits #
error message OF result := "some reversed digits found"
ELSE
# the code appears valid - check the check sum #
IF inverted OF result THEN
# the code was reversed - reverse the digits #
FOR d TO digits per side DO
INT right digit
= ( digits OF result )[ ( upc digits + 1 ) - d ];
( digits OF result )[ ( upc digits + 1 ) - d ]
:= ( digits OF result )[ d ];
( digits OF result )[ d ] := right digit
OD
FI;
INT check sum := 0;
FOR d FROM 1 BY 2 TO upc digits DO check sum +:= 3 * ( digits OF result )[ d ] OD;
FOR d FROM 2 BY 2 TO upc digits DO check sum +:= ( digits OF result )[ d ] OD;
IF check sum MOD 10 /= 0 THEN
# invalid check digit #
error message OF result := "incorrect check digit"
ELSE
# the UPC code appears valid #
valid OF result := TRUE
FI
FI
FI
FI
FI;
result
END; # parse upc #
# task test cases #
[]STRING tests =
( " # # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # # "
, " # # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # # "
, " # # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # # "
, " # # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # # "
, " # # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # # "
, " # # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # # "
, " # # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # # "
, " # # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # # "
, " # # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # # "
, " # # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # # "
);
FOR t pos FROM LWB tests TO UPB tests DO
UPC code = parse upc( tests[ t pos ] );
print( ( whole( t pos, -2 ), ":" ) );
IF NOT valid OF code THEN
# invalid UPC code #
print( ( " error: ", error message OF code, newline ) )
ELSE
# valid code #
FOR d TO upc digits - 1 DO print( ( whole( ( digits OF code )[ d ], -2 ) ) ) OD;
print( ( " valid" ) );
IF inverted OF code THEN print( ( " (inverted)" ) ) FI;
print( ( newline ) )
FI
OD
END |
http://rosettacode.org/wiki/Update_a_configuration_file | Update a configuration file | We have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines begininning with a hash or a semicolon are ignored by the application
# program. Blank lines are also ignored by the application program.
# The first word on each non comment line is the configuration option.
# Remaining words or numbers on the line are configuration parameter
# data fields.
# Note that configuration option names are not case sensitive. However,
# configuration parameter data is case sensitive and the lettercase must
# be preserved.
# This is a favourite fruit
FAVOURITEFRUIT banana
# This is a boolean that should be set
NEEDSPEELING
# This boolean is commented out
; SEEDSREMOVED
# How many bananas we have
NUMBEROFBANANAS 48
The task is to manipulate the configuration file as follows:
Disable the needspeeling option (using a semicolon prefix)
Enable the seedsremoved option by removing the semicolon and any leading whitespace
Change the numberofbananas parameter to 1024
Enable (or create if it does not exist in the file) a parameter for numberofstrawberries with a value of 62000
Note that configuration option names are not case sensitive. This means that changes should be effected, regardless of the case.
Options should always be disabled by prefixing them with a semicolon.
Lines beginning with hash symbols should not be manipulated and left unchanged in the revised file.
If a configuration option does not exist within the file (in either enabled or disabled form), it should be added during this update. Duplicate configuration option names in the file should be removed, leaving just the first entry.
For the purpose of this task, the revised file should contain appropriate entries, whether enabled or not for needspeeling,seedsremoved,numberofbananas and numberofstrawberries.)
The update should rewrite configuration option names in capital letters. However lines beginning with hashes and any parameter data must not be altered (eg the banana for favourite fruit must not become capitalized). The update process should also replace double semicolon prefixes with just a single semicolon (unless it is uncommenting the option, in which case it should remove all leading semicolons).
Any lines beginning with a semicolon or groups of semicolons, but no following option should be removed, as should any leading or trailing whitespace on the lines. Whitespace between the option and parameters should consist only of a single
space, and any non-ASCII extended characters, tabs characters, or control codes
(other than end of line markers), should also be removed.
Related tasks
Read a configuration file
| #Fortran | Fortran | PROGRAM TEST !Define some data aggregates, then write and read them.
CHARACTER*28 FAVOURITEFRUIT
LOGICAL NEEDSPEELING
LOGICAL SEEDSREMOVED
INTEGER NUMBEROFBANANAS
NAMELIST /FRUIT/ FAVOURITEFRUIT,NEEDSPEELING,SEEDSREMOVED,
1 NUMBEROFBANANAS
INTEGER F !An I/O unit number.
F = 10 !This will do.
Create an example file to show its format.
OPEN(F,FILE="Basket.txt",STATUS="REPLACE",ACTION="WRITE", !First, prepare a recipient file.
1 DELIM="QUOTE") !CHARACTER variables will be enquoted.
FAVOURITEFRUIT = "Banana"
NEEDSPEELING = .TRUE.
SEEDSREMOVED = .FALSE.
NUMBEROFBANANAS = 48
WRITE (F,FRUIT) !Write the lot in one go.
CLOSE (F) !Finished with output.
Can now read from the file.
OPEN(F,FILE="Basket.txt",STATUS="OLD",ACTION="READ", !Get it back.
1 DELIM="QUOTE")
READ (F,FRUIT) !Read who knows what.
WRITE (6,FRUIT)
END |
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
| #Ceylon | Ceylon | shared void run() {
print("enter any text here");
value text = process.readLine();
print(text);
print("enter the number 75000 here");
if (is Integer number = Integer.parse(process.readLine() else "")) {
print("``number == 75k then number else "close enough"``");
}
else {
print("That was not a number per se.");
}
} |
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
| #Clojure | Clojure | (import '(java.util Scanner))
(def scan (Scanner. *in*))
(def s (.nextLine scan))
(def n (.nextInt scan)) |
http://rosettacode.org/wiki/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #Frink | Frink |
s = input["Enter a string: "]
i = parseInt[input["Enter an integer: "]]
|
http://rosettacode.org/wiki/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #Gambas | Gambas | hTextBox As TextBox
hValueBox As ValueBox
hLabel As Label
Public Sub Form_Open()
With Me
.Height = 100
.Width = 300
.padding = 5
.Arrangement = Arrange.Vertical
.Title = "User input/Graphical"
End With
hTextBox = New TextBox(Me) As "TextBox1"
hTextBox.Expand = True
hValueBox = New ValueBox(Me) As "ValueBox1"
hValueBox.Expand = True
hLabel = New Label(Me)
hLabel.expand = True
End
Public Sub TextBox1_Change()
hLabel.text = hTextBox.Text & " - " & Str(hValueBox.value)
End
Public Sub valueBox1_Change()
TextBox1_Change
End |
http://rosettacode.org/wiki/UTF-8_encode_and_decode | UTF-8 encode and decode | As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the UTF-8 encoding.
Then you have to write the corresponding decoder that takes a sequence of 1-4 UTF-8 encoded bytes and return the corresponding unicode character.
Demonstrate the functionality of your encoder and decoder on the following five characters:
Character Name Unicode UTF-8 encoding (hex)
---------------------------------------------------------------------------------
A LATIN CAPITAL LETTER A U+0041 41
ö LATIN SMALL LETTER O WITH DIAERESIS U+00F6 C3 B6
Ж CYRILLIC CAPITAL LETTER ZHE U+0416 D0 96
€ EURO SIGN U+20AC E2 82 AC
𝄞 MUSICAL SYMBOL G CLEF U+1D11E F0 9D 84 9E
Provided below is a reference implementation in Common Lisp.
| #Forth | Forth | : showbytes ( c-addr u -- )
over + swap ?do
i c@ 3 .r loop ;
: test {: xc -- :}
xc xemit xc 6 .r xc pad xc!+ pad tuck - ( c-addr u )
2dup showbytes drop xc@+ xc <> abort" test failed" drop cr ;
hex
$41 test $f6 test $416 test $20ac test $1d11e test
\ can also be written as
\ 'A' test 'ö' test 'Ж' test '€' test '𝄞' test
|
http://rosettacode.org/wiki/UTF-8_encode_and_decode | UTF-8 encode and decode | As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the UTF-8 encoding.
Then you have to write the corresponding decoder that takes a sequence of 1-4 UTF-8 encoded bytes and return the corresponding unicode character.
Demonstrate the functionality of your encoder and decoder on the following five characters:
Character Name Unicode UTF-8 encoding (hex)
---------------------------------------------------------------------------------
A LATIN CAPITAL LETTER A U+0041 41
ö LATIN SMALL LETTER O WITH DIAERESIS U+00F6 C3 B6
Ж CYRILLIC CAPITAL LETTER ZHE U+0416 D0 96
€ EURO SIGN U+20AC E2 82 AC
𝄞 MUSICAL SYMBOL G CLEF U+1D11E F0 9D 84 9E
Provided below is a reference implementation in Common Lisp.
| #Go | Go | package main
import (
"bytes"
"encoding/hex"
"fmt"
"log"
"strings"
)
var testCases = []struct {
rune
string
}{
{'A', "41"},
{'ö', "C3 B6"},
{'Ж', "D0 96"},
{'€', "E2 82 AC"},
{'𝄞', "F0 9D 84 9E"},
}
func main() {
for _, tc := range testCases {
// derive some things from test data
u := fmt.Sprintf("U+%04X", tc.rune)
b, err := hex.DecodeString(strings.Replace(tc.string, " ", "", -1))
if err != nil {
log.Fatal("bad test data")
}
// exercise encoder and decoder on test data
e := encodeUTF8(tc.rune)
d := decodeUTF8(b)
// show function return values
fmt.Printf("%c %-7s %X\n", d, u, e)
// validate return values against test data
if !bytes.Equal(e, b) {
log.Fatal("encodeUTF8 wrong")
}
if d != tc.rune {
log.Fatal("decodeUTF8 wrong")
}
}
}
const (
// first byte of a 2-byte encoding starts 110 and carries 5 bits of data
b2Lead = 0xC0 // 1100 0000
b2Mask = 0x1F // 0001 1111
// first byte of a 3-byte encoding starts 1110 and carries 4 bits of data
b3Lead = 0xE0 // 1110 0000
b3Mask = 0x0F // 0000 1111
// first byte of a 4-byte encoding starts 11110 and carries 3 bits of data
b4Lead = 0xF0 // 1111 0000
b4Mask = 0x07 // 0000 0111
// non-first bytes start 10 and carry 6 bits of data
mbLead = 0x80 // 1000 0000
mbMask = 0x3F // 0011 1111
)
func encodeUTF8(r rune) []byte {
switch i := uint32(r); {
case i <= 1<<7-1: // max code point that encodes into a single byte
return []byte{byte(r)}
case i <= 1<<11-1: // into two bytes
return []byte{
b2Lead | byte(r>>6),
mbLead | byte(r)&mbMask}
case i <= 1<<16-1: // three
return []byte{
b3Lead | byte(r>>12),
mbLead | byte(r>>6)&mbMask,
mbLead | byte(r)&mbMask}
default:
return []byte{
b4Lead | byte(r>>18),
mbLead | byte(r>>12)&mbMask,
mbLead | byte(r>>6)&mbMask,
mbLead | byte(r)&mbMask}
}
}
func decodeUTF8(b []byte) rune {
switch b0 := b[0]; {
case b0 < 0x80:
return rune(b0)
case b0 < 0xE0:
return rune(b0&b2Mask)<<6 |
rune(b[1]&mbMask)
case b0 < 0xF0:
return rune(b0&b3Mask)<<12 |
rune(b[1]&mbMask)<<6 |
rune(b[2]&mbMask)
default:
return rune(b0&b4Mask)<<18 |
rune(b[1]&mbMask)<<12 |
rune(b[2]&mbMask)<<6 |
rune(b[3]&mbMask)
}
} |
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a 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.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (int argc, char * argv [])
{
char Buffer [1024];
size_t Size = sizeof (Buffer);
if (0 == Query (Buffer, &Size))
{
printf ("failed to call Query\n");
}
else
{
char * Ptr = Buffer;
while (Size-- > 0) putchar (*Ptr++);
putchar ('\n');
}
}
Implement the missing Query function in your language, and let this C program call it. The function should place the string Here am I into the buffer which is passed to it as the parameter Data. The buffer size in bytes is passed as the parameter Length. When there is no room in the buffer, Query shall return 0. Otherwise it overwrites the beginning of Buffer, sets the number of overwritten bytes into Length and returns 1.
| #Pascal | Pascal | without js -- (peek/poke, call_back)
constant Here_am_I = "Here am I"
function Query(atom pData, pLength)
integer len = peekNS(pLength,machine_word(),0)
if poke_string(pData,len,Here_am_I) then
return 0
end if
pokeN(pLength,length(Here_am_I)+1,machine_word())
return 1
end function
constant Query_cb = call_back(Query)
|
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a 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.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (int argc, char * argv [])
{
char Buffer [1024];
size_t Size = sizeof (Buffer);
if (0 == Query (Buffer, &Size))
{
printf ("failed to call Query\n");
}
else
{
char * Ptr = Buffer;
while (Size-- > 0) putchar (*Ptr++);
putchar ('\n');
}
}
Implement the missing Query function in your language, and let this C program call it. The function should place the string Here am I into the buffer which is passed to it as the parameter Data. The buffer size in bytes is passed as the parameter Length. When there is no room in the buffer, Query shall return 0. Otherwise it overwrites the beginning of Buffer, sets the number of overwritten bytes into Length and returns 1.
| #Phix | Phix | without js -- (peek/poke, call_back)
constant Here_am_I = "Here am I"
function Query(atom pData, pLength)
integer len = peekNS(pLength,machine_word(),0)
if poke_string(pData,len,Here_am_I) then
return 0
end if
pokeN(pLength,length(Here_am_I)+1,machine_word())
return 1
end function
constant Query_cb = call_back(Query)
|
http://rosettacode.org/wiki/URL_parser | URL parser | URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
According to the standards, the characters:
! * ' ( ) ; : @ & = + $ , / ? % # [ ]
only need to be percent-encoded (%) in case of possible confusion.
Also note that the path, query and fragment are case sensitive, even if the scheme and domain are not.
The way the returned information is provided (set of variables, array, structured, record, object,...)
is language-dependent and left to the programmer, but the code should be clear enough to reuse.
Extra credit is given for clear error diagnostics.
Here is the official standard: https://tools.ietf.org/html/rfc3986,
and here is a simpler BNF: http://www.w3.org/Addressing/URL/5_URI_BNF.html.
Test cases
According to T. Berners-Lee
foo://example.com:8042/over/there?name=ferret#nose should parse into:
scheme = foo
domain = example.com
port = :8042
path = over/there
query = name=ferret
fragment = nose
urn:example:animal:ferret:nose should parse into:
scheme = urn
path = example:animal:ferret:nose
other URLs that must be parsed include:
jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true
ftp://ftp.is.co.za/rfc/rfc1808.txt
http://www.ietf.org/rfc/rfc2396.txt#header1
ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two
mailto:[email protected]
news:comp.infosystems.www.servers.unix
tel:+1-816-555-1212
telnet://192.0.2.16:80/
urn:oasis:names:specification:docbook:dtd:xml:4.1.2
| #M2000_Interpreter | M2000 Interpreter |
Module checkit {
any=lambda (z$)->{=lambda z$ (a$)->instr(z$,a$)>0}
one=lambda (z$)->{=lambda z$ (a$)->z$=a$}
number$="0123456789"
series=Lambda -> {
func=Array([])
=lambda func (&line$, &res$)->{
if line$="" then exit
k=each(func)
def p=0,ok as boolean
while k {
ok=false : p++ : f=array(k)
if not f(mid$(line$,p,1)) then exit
ok=true
}
if ok then res$=left$(line$, p) : line$=mid$(line$, p+1)
=ok
}
}
is_any=lambda series, any (c$) ->series(any(c$))
is_one=lambda series, one (c$) ->series(one(c$))
Is_Alpha=series(lambda (a$)-> a$ ~ "[a-zA-Z]")
Is_digit=series(any(number$))
Is_hex=any(number$+"abcdefABCDEF")
optionals=Lambda -> {
func=Array([])
=lambda func (&line$, &res$)->{
k=each(func)
def ok as boolean
while k {
f=array(k)
if f(&line$,&res$) then ok=true : exit
}
=ok
}
}
repeated=Lambda (func)-> {
=lambda func (&line$, &res$)->{
def ok as boolean, a$
res$=""
do {
sec=len(line$)
if not func(&line$,&a$) then exit
res$+=a$
ok=true
} until line$="" or sec=len(line$)
=ok
}
}
oneAndoptional=lambda (func1, func2) -> {
=lambda func1, func2 (&line$, &res$)->{
def ok as boolean, a$
res$=""
if not func1(&line$,&res$) then exit
if func2(&line$,&a$) then res$+=a$
=True
}
}
many=Lambda -> {
func=Array([])
=lambda func (&line$, &res$)->{
k=each(func)
def p=0,ok as boolean, acc$
oldline$=line$
while k {
ok=false
res$=""
if line$="" then exit
f=array(k)
if not f(&line$,&res$) then exit
acc$+=res$
ok=true
}
if not ok then {line$=oldline$} else res$=acc$
=ok
}
}
is_safe=series(any("$-_@.&"))
Is_extra=series(any("!*'(),"+chr$(34)))
Is_Escape=series(any("%"), is_hex, is_hex)
\\Is_reserved=series(any("=;/#?: "))
is_xalpha=optionals(Is_Alpha, is_digit, is_safe, is_extra, is_escape)
is_xalphas=oneAndoptional(is_xalpha,repeated(is_xalpha))
is_xpalpha=optionals(is_xalpha, is_one("+"))
is_xpalphas=oneAndoptional(is_xpalpha,repeated(is_xpalpha))
Is_ialpha=oneAndoptional(Is_Alpha,repeated(is_xpalphas))
is_fragmentid=lambda is_xalphas (&lines$, &res$) -> {
=is_xalphas(&lines$, &res$)
}
is_search=oneAndoptional(is_xalphas, repeated(many(series(one("+")), is_xalphas)))
is_void=lambda (f)-> {
=lambda f (&oldline$, &res$)-> {
line$=oldline$
if f(&line$, &res$) then {oldline$=line$ } else res$=""
=true
}
}
is_scheme=is_ialpha
is_path=repeated(oneAndoptional(is_void(is_xpalphas), series(one("/"))))
is_uri=oneAndoptional(many(is_scheme, series(one(":")), is_path), many(series(one("?")),is_search))
is_fragmentaddress=oneAndoptional(is_uri, many(series(one("#")),is_fragmentid ))
data "foo://example.com:8042/over/there?name=ferret#nose"
data "urn:example:animal:ferret:nose"
data "jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true "
data "ftp://ftp.is.co.za/rfc/rfc1808.txt"
data "http://www.ietf.org/rfc/rfc2396.txt#header1"
data "ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two"
data "mailto:[email protected]"
data "tel:+1-816-555-1212"
data "telnet://192.0.2.16:80/"
data "urn:oasis:names:specification:docbook:dtd:xml:4.1.2"
while not empty {
read What$
pen 15 {
Print What$
}
a$=""
If is_scheme(&What$, &a$) Then Print "Scheme=";a$ : What$=mid$(What$,2)
If is_path(&What$, &a$) Then {
count=0
while left$(a$, 1)="/" { a$=mid$(a$,2): count++}
if count>1 then {
domain$=leftpart$(a$+"/", "/")
a$=rightpart$(a$,"/")
if domain$<>"" Then Print "Domain:";Domain$
if a$<>"" Then Print "Path:";a$
} else.if left$(What$,1) =":" then {
Print "path:";a$+What$: What$=""
} Else Print "Data:"; a$
}
if left$(What$,1) =":" then {
is_number=repeated(is_digit)
What$=mid$(What$,2): If is_number(&What$, &a$) Then Print "Port:";a$
if not left$(What$,1)="/" then exit
If is_path(&What$, &a$) Then {
while left$(a$, 1)="/" { a$=mid$(a$,2)}
if a$<>"" Then Print "Path:";a$
}
}
if left$(What$, 1)="?" then {
What$=mid$(What$,2)
If is_search(&What$, &a$) Then {
v$=""
if left$(What$, 1)="=" then {
What$=mid$(What$,2)
If is_search(&What$, &v$) Then Print "Query:";a$;"=";v$
} else Print "Query:";a$
}
}
While left$(What$, 1)="#" {
What$=mid$(What$,2)
if not is_xalphas(&What$, &a$) Then exit
Print "fragment:";a$
}
if What$<>"" Then Print "Data:"; What$
}
}
Checkit
|
http://rosettacode.org/wiki/URL_parser | URL parser | URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
According to the standards, the characters:
! * ' ( ) ; : @ & = + $ , / ? % # [ ]
only need to be percent-encoded (%) in case of possible confusion.
Also note that the path, query and fragment are case sensitive, even if the scheme and domain are not.
The way the returned information is provided (set of variables, array, structured, record, object,...)
is language-dependent and left to the programmer, but the code should be clear enough to reuse.
Extra credit is given for clear error diagnostics.
Here is the official standard: https://tools.ietf.org/html/rfc3986,
and here is a simpler BNF: http://www.w3.org/Addressing/URL/5_URI_BNF.html.
Test cases
According to T. Berners-Lee
foo://example.com:8042/over/there?name=ferret#nose should parse into:
scheme = foo
domain = example.com
port = :8042
path = over/there
query = name=ferret
fragment = nose
urn:example:animal:ferret:nose should parse into:
scheme = urn
path = example:animal:ferret:nose
other URLs that must be parsed include:
jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true
ftp://ftp.is.co.za/rfc/rfc1808.txt
http://www.ietf.org/rfc/rfc2396.txt#header1
ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two
mailto:[email protected]
news:comp.infosystems.www.servers.unix
tel:+1-816-555-1212
telnet://192.0.2.16:80/
urn:oasis:names:specification:docbook:dtd:xml:4.1.2
| #Mathematica.2FWolfram_Language | Mathematica/Wolfram Language | URLParse["foo://example.com:8042/over/there?name=ferret#nose"] |
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #Free_Pascal | Free Pascal | function urlEncode(data: string): AnsiString;
var
ch: AnsiChar;
begin
Result := '';
for ch in data do begin
if ((Ord(ch) < 65) or (Ord(ch) > 90)) and ((Ord(ch) < 97) or (Ord(ch) > 122)) then begin
Result := Result + '%' + IntToHex(Ord(ch), 2);
end else
Result := Result + ch;
end;
end; |
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #FreeBASIC | FreeBASIC |
Dim Shared As String lookUp(256)
For cadena As Integer = 0 To 256
lookUp(cadena) = "%" + Hex(cadena)
Next cadena
Function string2url(cadena As String) As String
Dim As String cadTemp, cadDevu
For j As Integer = 1 To Len(cadena)
cadTemp = Mid(cadena, j, 1)
If Instr( "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz", cadTemp) Then
cadDevu &= cadTemp
Else
cadDevu &= lookUp(Asc(cadTemp))
End If
Next j
Return cadDevu
End Function
Dim As String URL = "http://foo bar/"
Print "Supplied URL '"; URL; "'"
Print "URL encoding '"; string2url(URL); "'"
Sleep
|
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #E | E | def x := 1
x + x # returns 2 |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #EasyLang | EasyLang | # it is statically typed
#
# global number variable
n = 99
print n
# global array of numbers
a[] = [ 2.1 3.14 3 ]
#
func f . .
# i is local, because it is first used in the function
for i range len a[]
print a[i]
.
.
call f
#
# string
domain$ = "easylang.online"
print domain$
#
# array of strings
fruits$[] = [ "apple" "banana" "orange" ]
print fruits$[] |
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 A:
0
Using B:
0 0
Using C:
0 0 1
Using B:
0 0 1 0
Using C: (zero last occurred two steps back - before the one)
0 0 1 0 2
Using B:
0 0 1 0 2 0
Using C: (two last occurred two steps back - before the zero)
0 0 1 0 2 0 2 2
Using C: (two last occurred one step back)
0 0 1 0 2 0 2 2 1
Using C: (one last appeared six steps back)
0 0 1 0 2 0 2 2 1 6
...
Task
Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
Use it to display here, on this page:
The first ten terms of the sequence.
Terms 991 - to - 1000 of the sequence.
References
Don't Know (the Van Eck Sequence) - Numberphile video.
Wikipedia Article: Van Eck's Sequence.
OEIS sequence: A181391.
| #JavaScript | JavaScript | (() => {
'use strict';
// vanEck :: Int -> [Int]
const vanEck = n =>
reverse(
churchNumeral(n)(
xs => 0 < xs.length ? cons(
maybe(
0, succ,
elemIndex(xs[0], xs.slice(1))
),
xs
) : [0]
)([])
);
// TEST -----------------------------------------------
const main = () => {
console.log('VanEck series:\n')
showLog('First 10 terms', vanEck(10))
showLog('Terms 991-1000', vanEck(1000).slice(990))
};
// GENERIC FUNCTIONS ----------------------------------
// Just :: a -> Maybe a
const Just = x => ({
type: 'Maybe',
Nothing: false,
Just: x
});
// Nothing :: Maybe a
const Nothing = () => ({
type: 'Maybe',
Nothing: true,
});
// churchNumeral :: Int -> (a -> a) -> a -> a
const churchNumeral = n => f => x =>
Array.from({
length: n
}, () => f)
.reduce((a, g) => g(a), x)
// cons :: a -> [a] -> [a]
const cons = (x, xs) => [x].concat(xs)
// elemIndex :: Eq a => a -> [a] -> Maybe Int
const elemIndex = (x, xs) => {
const i = xs.indexOf(x);
return -1 === i ? (
Nothing()
) : Just(i);
};
// maybe :: b -> (a -> b) -> Maybe a -> b
const maybe = (v, f, m) =>
m.Nothing ? v : f(m.Just);
// reverse :: [a] -> [a]
const reverse = xs =>
'string' !== typeof xs ? (
xs.slice(0).reverse()
) : xs.split('').reverse().join('');
// showLog :: a -> IO ()
const showLog = (...args) =>
console.log(
args
.map(JSON.stringify)
.join(' -> ')
);
// succ :: Int -> Int
const succ = x => 1 + x;
// MAIN ---
return main();
})(); |
http://rosettacode.org/wiki/Vampire_number | Vampire number | A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
together they consist of exactly the same decimal digits as the original number
at most one of them has a trailing zero
An example of a vampire number and its fangs: 1260 : (21, 60)
Task
Print the first 25 vampire numbers and their fangs.
Check if the following numbers are vampire numbers and, if so, print them and their fangs:
16758243290880, 24959017348650, 14593825548650
Note that a vampire number can have more than one pair of fangs.
See also
numberphile.com.
vampire search algorithm
vampire numbers on OEIS
| #PureBasic | PureBasic | EnableExplicit
DisableDebugger
Macro CheckVamp(CheckNum)
c=0 : i=CheckNum : Print(~"\nCheck number: "+Str(i)+~"\n")
Gosub VampireLoop : If c=0 : Print(Str(i)+" is not vampiric.") : EndIf : PrintN("")
EndMacro
Procedure.i Factor(number.i,counter.i)
If number>0 And number>=counter*counter And number%counter=0
ProcedureReturn counter
EndIf
ProcedureReturn 0
EndProcedure
Procedure.b IsVampire(f1.i,f2.i)
Define a.s=Str(f1*f2),
b.s=Str(f1),
c.s=Str(f2),
d.s=b+c,
i.i
If Len(a)=Len(d) And Len(b)=Len(c)
While Len(a)
i=FindString(d,Left(a,1))
If i
a=Mid(a,2)
d=RemoveString(d,Mid(d,i,1),#PB_String_NoCase,i,1)
Else
ProcedureReturn #False
EndIf
Wend
ProcedureReturn Bool(Len(d)=0)
EndIf
ProcedureReturn #False
EndProcedure
OpenConsole("Vampire number")
Define i.i,
j.i,
m.i,
c.i=0
PrintN("The first 25 Vampire numbers...")
While c<25 : i+1 : Gosub VampireLoop : Wend
PrintN("")
CheckVamp(16758243290880) : CheckVamp(24959017348650) : CheckVamp(14593825548650)
Input()
End
VampireLoop:
For j=1 To Int(Sqr(i))
If Factor(i,j)>0
m=i/j
Else
Continue
EndIf
If IsVampire(m,j)
c+1
PrintN(RSet(Str(c),3," ")+". "+RSet(Str(i),10," ")+": ["+Str(j)+", "+Str(m)+"]")
EndIf
Next
Return |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #Maxima | Maxima | show([L]) := block([n], n: length(L), for i from 1 thru n do disp(L[i]))$
show(1, 2, 3, 4);
apply(show, [1, 2, 3, 4]);
/* Actually, the built-in function "disp" is already what we want */
disp(1, 2, 3, 4);
apply(disp, [1, 2, 3, 4]); |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #Metafont | Metafont | def print_arg(text t) =
for x = t:
if unknown x: message "unknown value"
elseif numeric x: message decimal x
elseif string x: message x
elseif path x: message "a path"
elseif pair x: message decimal (xpart(x)) & ", " & decimal (ypart(x))
elseif boolean x: if x: message "true!" else: message "false!" fi
elseif pen x: message "a pen"
elseif picture x: message "a picture"
elseif transform x: message "a transform" fi; endfor enddef;
print_arg("hello", x, 12, fullcircle, currentpicture, down, identity, false, pencircle);
end |
http://rosettacode.org/wiki/Vector | Vector | Task
Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented.
The Vector may be initialized in any reasonable way.
Start and end points, and direction
Angular coefficient and value (length)
The four operations to be implemented are:
Vector + Vector addition
Vector - Vector subtraction
Vector * scalar multiplication
Vector / scalar division
| #Swift | Swift | import Foundation
#if canImport(Numerics)
import Numerics
#endif
struct Vector<T: Numeric> {
var x: T
var y: T
func prettyPrinted(precision: Int = 4) -> String where T: CVarArg & FloatingPoint {
return String(format: "[%.\(precision)f, %.\(precision)f]", x, y)
}
static func +(lhs: Vector, rhs: Vector) -> Vector {
return Vector(x: lhs.x + rhs.x, y: lhs.y + rhs.y)
}
static func -(lhs: Vector, rhs: Vector) -> Vector {
return Vector(x: lhs.x - rhs.x, y: lhs.y - rhs.y)
}
static func *(lhs: Vector, scalar: T) -> Vector {
return Vector(x: lhs.x * scalar, y: lhs.y * scalar)
}
static func /(lhs: Vector, scalar: T) -> Vector where T: FloatingPoint {
return Vector(x: lhs.x / scalar, y: lhs.y / scalar)
}
static func /(lhs: Vector, scalar: T) -> Vector where T: BinaryInteger {
return Vector(x: lhs.x / scalar, y: lhs.y / scalar)
}
}
#if canImport(Numerics)
extension Vector where T: ElementaryFunctions {
static func fromPolar(radians: T, theta: T) -> Vector {
return Vector(x: radians * T.cos(theta), y: radians * T.sin(theta))
}
}
#else
extension Vector where T == Double {
static func fromPolar(radians: Double, theta: Double) -> Vector {
return Vector(x: radians * cos(theta), y: radians * sin(theta))
}
}
#endif
print(Vector(x: 4, y: 5))
print(Vector.fromPolar(radians: 3.0, theta: .pi / 3).prettyPrinted())
print((Vector(x: 2, y: 3) + Vector(x: 4, y: 6)))
print((Vector(x: 5.6, y: 1.3) - Vector(x: 4.2, y: 6.1)).prettyPrinted())
print((Vector(x: 3.0, y: 4.2) * 2.3).prettyPrinted())
print((Vector(x: 3.0, y: 4.2) / 2.3).prettyPrinted())
print(Vector(x: 3, y: 4) / 2) |
http://rosettacode.org/wiki/Vector | Vector | Task
Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented.
The Vector may be initialized in any reasonable way.
Start and end points, and direction
Angular coefficient and value (length)
The four operations to be implemented are:
Vector + Vector addition
Vector - Vector subtraction
Vector * scalar multiplication
Vector / scalar division
| #Tcl | Tcl | namespace path ::tcl::mathop
proc vec {op a b} {
if {[llength $a] == 1 && [llength $b] == 1} {
$op $a $b
} elseif {[llength $a]==1} {
lmap i $b {vec $op $a $i}
} elseif {[llength $b]==1} {
lmap i $a {vec $op $i $b}
} elseif {[llength $a] == [llength $b]} {
lmap i $a j $b {vec $op $i $j}
} else {error "length mismatch [llength $a] != [llength $b]"}
}
proc polar {r t} {
list [expr {$r * cos($t)}] [expr {$r * sin($t)}]
}
proc check {cmd res} {
set r [uplevel 1 $cmd]
if {$r eq $res} {
puts "Ok! $cmd \t = $res"
} else {
puts "ERROR: $cmd = $r \t expected $res"
}
}
check {vec + {5 7} {2 3}} {7 10}
check {vec - {5 7} {2 3}} {3 4}
check {vec * {5 7} 11} {55 77}
check {vec / {5 7} 2.0} {2.5 3.5}
check {polar 2 0.785398} {1.41421 1.41421} |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar cipher
Rot-13
Substitution Cipher
| #Smalltalk | Smalltalk |
prep := [:s | s select:[:ch | ch isLetter] thenCollect:[:ch | ch asUppercase]].
encrypt := [:s :cypher | (prep value:s) keysAndValuesCollect:[:i :ch | ch rot:((cypher at:((i-1)\\key size+1))-$A) ]].
decrypt := [:s :cypher | (prep value:s) keysAndValuesCollect:[:i :ch | ch rot:26-((cypher at:((i-1)\\key size+1))-$A) ]].
|
http://rosettacode.org/wiki/Vector_products | Vector products | A vector is defined as having three dimensions as being represented by an ordered collection of three numbers: (X, Y, Z).
If you imagine a graph with the x and y axis being at right angles to each other and having a third, z axis coming out of the page, then a triplet of numbers, (X, Y, Z) would represent a point in the region, and a vector from the origin to the point.
Given the vectors:
A = (a1, a2, a3)
B = (b1, b2, b3)
C = (c1, c2, c3)
then the following common vector products are defined:
The dot product (a scalar quantity)
A • B = a1b1 + a2b2 + a3b3
The cross product (a vector quantity)
A x B = (a2b3 - a3b2, a3b1 - a1b3, a1b2 - a2b1)
The scalar triple product (a scalar quantity)
A • (B x C)
The vector triple product (a vector quantity)
A x (B x C)
Task
Given the three vectors:
a = ( 3, 4, 5)
b = ( 4, 3, 5)
c = (-5, -12, -13)
Create a named function/subroutine/method to compute the dot product of two vectors.
Create a function to compute the cross product of two vectors.
Optionally create a function to compute the scalar triple product of three vectors.
Optionally create a function to compute the vector triple product of three vectors.
Compute and display: a • b
Compute and display: a x b
Compute and display: a • (b x c), the scalar triple product.
Compute and display: a x (b x c), the vector triple product.
References
A starting page on Wolfram MathWorld is Vector Multiplication .
Wikipedia dot product.
Wikipedia cross product.
Wikipedia triple product.
Related tasks
Dot product
Quaternion type
| #F.23 | F# | let dot (ax, ay, az) (bx, by, bz) =
ax * bx + ay * by + az * bz
let cross (ax, ay, az) (bx, by, bz) =
(ay*bz - az*by, az*bx - ax*bz, ax*by - ay*bx)
let scalTrip a b c =
dot a (cross b c)
let vecTrip a b c =
cross a (cross b c)
[<EntryPoint>]
let main _ =
let a = (3.0, 4.0, 5.0)
let b = (4.0, 3.0, 5.0)
let c = (-5.0, -12.0, -13.0)
printfn "%A" (dot a b)
printfn "%A" (cross a b)
printfn "%A" (scalTrip a b c)
printfn "%A" (vecTrip a b c)
0 // return an integer exit code |
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded checksum is correct.
Demonstrate that your code passes the test-cases listed below.
Details
The format of an ISIN is as follows:
┌───────────── a 2-character ISO country code (A-Z)
│ ┌─────────── a 9-character security code (A-Z, 0-9)
│ │ ┌── a checksum digit (0-9)
AU0000XVGZA3
For this task, you may assume that any 2-character alphabetic sequence is a valid country code.
The checksum can be validated as follows:
Replace letters with digits, by converting each character from base 36 to base 10, e.g. AU0000XVGZA3 →1030000033311635103.
Perform the Luhn test on this base-10 number.
There is a separate task for this test: Luhn test of credit card numbers.
You don't have to replicate the implementation of this test here ─── you can just call the existing function from that task. (Add a comment stating if you did this.)
Test cases
ISIN
Validity
Comment
US0378331005
valid
US0373831005
not valid
The transposition typo is caught by the checksum constraint.
U50378331005
not valid
The substitution typo is caught by the format constraint.
US03378331005
not valid
The duplication typo is caught by the format constraint.
AU0000XVGZA3
valid
AU0000VXGZA3
valid
Unfortunately, not all transposition typos are caught by the checksum constraint.
FR0000988040
valid
(The comments are just informational. Your function should simply return a Boolean result. See #Raku for a reference solution.)
Related task:
Luhn test of credit card numbers
Also see
Interactive online ISIN validator
Wikipedia article: International Securities Identification Number
| #Mathematica_.2F_Wolfram_Language | Mathematica / Wolfram Language | ClearAll[LuhnQ, VakudISINQ]
LuhnQ[n_Integer] := Block[{digits = Reverse@IntegerDigits@n}, Mod[Total[{digits[[;; ;; 2]], IntegerDigits[2 #] & /@ digits[[2 ;; ;; 2]]}, -1], 10] == 0]
VakudISINQ[sin_String] := Module[{s = ToUpperCase[sin]},
If[StringMatchQ[s,
LetterCharacter ~~ LetterCharacter ~~
Repeated[DigitCharacter | LetterCharacter, {9}] ~~
DigitCharacter],
s = StringJoin[
Characters[s] /.
Thread[CharacterRange["A", "Z"] -> ToString /@ Range[10, 35]]];
LuhnQ[ToExpression[s]]
,
False
]
]
VakudISINQ /@ {"US0378331005", "US0373831005", "U50378331005", "US03378331005", "AU0000XVGZA3", "AU0000VXGZA3", "FR0000988040"} |
http://rosettacode.org/wiki/Validate_International_Securities_Identification_Number | Validate International Securities Identification Number | An International Securities Identification Number (ISIN) is a unique international identifier for a financial security such as a stock or bond.
Task
Write a function or program that takes a string as input, and checks whether it is a valid ISIN.
It is only valid if it has the correct format, and the embedded checksum is correct.
Demonstrate that your code passes the test-cases listed below.
Details
The format of an ISIN is as follows:
┌───────────── a 2-character ISO country code (A-Z)
│ ┌─────────── a 9-character security code (A-Z, 0-9)
│ │ ┌── a checksum digit (0-9)
AU0000XVGZA3
For this task, you may assume that any 2-character alphabetic sequence is a valid country code.
The checksum can be validated as follows:
Replace letters with digits, by converting each character from base 36 to base 10, e.g. AU0000XVGZA3 →1030000033311635103.
Perform the Luhn test on this base-10 number.
There is a separate task for this test: Luhn test of credit card numbers.
You don't have to replicate the implementation of this test here ─── you can just call the existing function from that task. (Add a comment stating if you did this.)
Test cases
ISIN
Validity
Comment
US0378331005
valid
US0373831005
not valid
The transposition typo is caught by the checksum constraint.
U50378331005
not valid
The substitution typo is caught by the format constraint.
US03378331005
not valid
The duplication typo is caught by the format constraint.
AU0000XVGZA3
valid
AU0000VXGZA3
valid
Unfortunately, not all transposition typos are caught by the checksum constraint.
FR0000988040
valid
(The comments are just informational. Your function should simply return a Boolean result. See #Raku for a reference solution.)
Related task:
Luhn test of credit card numbers
Also see
Interactive online ISIN validator
Wikipedia article: International Securities Identification Number
| #Nim | Nim | import strformat
const
DigitRange = '0'..'9'
UpperCaseRange = 'A'..'Z'
type ISINError = object of ValueError
proc luhn(s: string): bool =
const m = [0, 2, 4, 6, 8, 1, 3, 5, 7, 9]
var sum = 0
var odd = true
for i in countdown(s.high, 0):
let digit = ord(s[i]) - ord('0')
sum += (if odd: digit else: m[digit])
odd = not odd
result = sum mod 10 == 0
proc validateISIN(s: string) =
if s.len != 12:
raise newException(ISINError, "wrong length")
if s[0] notin UpperCaseRange or s[1] notin UpperCaseRange:
raise newException(ISINError, "wrong country code")
if s[11] notin DigitRange:
raise newException(ISINError, "wrong checksum character")
var t: string
for ch in s:
case ch
of '0'..'9': t.add ch
of 'A'..'Z': t.addInt ord(ch) - ord('A') + 10
else: raise newException(ISINError, "invalid characters in code")
if not t.luhn():
raise newException(ISINError, "checksum error")
when isMainModule:
for isin in ["US0378331005", "US0373831005", "U50378331005",
"US03378331005", "AU0000XVGZA3", "AU0000VXGZA3", "FR0000988040"]:
try:
isin.validateISIN()
echo &"{isin} is valid."
except ISINError:
echo &"{isin} is not valid: {getCurrentExceptionMsg()}." |
http://rosettacode.org/wiki/Van_der_Corput_sequence | Van der Corput sequence | When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of
2
0
{\displaystyle 2^{0}}
; the digit in the next column to the left has a multiplier of
2
1
{\displaystyle 2^{1}}
; and so on.
So in the following table:
0.
1.
10.
11.
...
the binary number "10" is
1
×
2
1
+
0
×
2
0
{\displaystyle 1\times 2^{1}+0\times 2^{0}}
.
You can also have binary digits to the right of the “point”, just as in the decimal number system. In that case, the digit in the place immediately to the right of the point has a weight of
2
−
1
{\displaystyle 2^{-1}}
, or
1
/
2
{\displaystyle 1/2}
.
The weight for the second column to the right of the point is
2
−
2
{\displaystyle 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
. And so on.
If you take the integer binary count of the first table, and reflect the digits about the binary point, you end up with the van der Corput sequence of numbers in base 2.
.0
.1
.01
.11
...
The third member of the sequence, binary 0.01, is therefore
0
×
2
−
1
+
1
×
2
−
2
{\displaystyle 0\times 2^{-1}+1\times 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
.
Distribution of 2500 points each: Van der Corput (top) vs pseudorandom
0
≤
x
<
1
{\displaystyle 0\leq x<1}
Monte Carlo simulations
This sequence is also a superset of the numbers representable by the "fraction" field of an old IEEE floating point standard. In that standard, the "fraction" field represented the fractional part of a binary number beginning with "1." e.g. 1.101001101.
Hint
A hint at a way to generate members of the sequence is to modify a routine used to change the base of an integer:
>>> def base10change(n, base):
digits = []
while n:
n,remainder = divmod(n, base)
digits.insert(0, remainder)
return digits
>>> base10change(11, 2)
[1, 0, 1, 1]
the above showing that 11 in decimal is
1
×
2
3
+
0
×
2
2
+
1
×
2
1
+
1
×
2
0
{\displaystyle 1\times 2^{3}+0\times 2^{2}+1\times 2^{1}+1\times 2^{0}}
.
Reflected this would become .1101 or
1
×
2
−
1
+
1
×
2
−
2
+
0
×
2
−
3
+
1
×
2
−
4
{\displaystyle 1\times 2^{-1}+1\times 2^{-2}+0\times 2^{-3}+1\times 2^{-4}}
Task description
Create a function/method/routine that given n, generates the n'th term of the van der Corput sequence in base 2.
Use the function to compute and display the first ten members of the sequence. (The first member of the sequence is for n=0).
As a stretch goal/extra credit, compute and show members of the sequence for bases other than 2.
See also
The Basic Low Discrepancy Sequences
Non-decimal radices/Convert
Van der Corput sequence
| #Java | Java | public class VanDerCorput{
public static double vdc(int n){
double vdc = 0;
int denom = 1;
while(n != 0){
vdc += n % 2.0 / (denom *= 2);
n /= 2;
}
return vdc;
}
public static void main(String[] args){
for(int i = 0; i <= 10; i++){
System.out.println(vdc(i));
}
}
} |
http://rosettacode.org/wiki/Van_der_Corput_sequence | Van der Corput sequence | When counting integers in binary, if you put a (binary) point to the righEasyLangt of the count then the column immediately to the left denotes a digit with a multiplier of
2
0
{\displaystyle 2^{0}}
; the digit in the next column to the left has a multiplier of
2
1
{\displaystyle 2^{1}}
; and so on.
So in the following table:
0.
1.
10.
11.
...
the binary number "10" is
1
×
2
1
+
0
×
2
0
{\displaystyle 1\times 2^{1}+0\times 2^{0}}
.
You can also have binary digits to the right of the “point”, just as in the decimal number system. In that case, the digit in the place immediately to the right of the point has a weight of
2
−
1
{\displaystyle 2^{-1}}
, or
1
/
2
{\displaystyle 1/2}
.
The weight for the second column to the right of the point is
2
−
2
{\displaystyle 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
. And so on.
If you take the integer binary count of the first table, and reflect the digits about the binary point, you end up with the van der Corput sequence of numbers in base 2.
.0
.1
.01
.11
...
The third member of the sequence, binary 0.01, is therefore
0
×
2
−
1
+
1
×
2
−
2
{\displaystyle 0\times 2^{-1}+1\times 2^{-2}}
or
1
/
4
{\displaystyle 1/4}
.
Distribution of 2500 points each: Van der Corput (top) vs pseudorandom
0
≤
x
<
1
{\displaystyle 0\leq x<1}
Monte Carlo simulations
This sequence is also a superset of the numbers representable by the "fraction" field of an old IEEE floating point standard. In that standard, the "fraction" field represented the fractional part of a binary number beginning with "1." e.g. 1.101001101.
Hint
A hint at a way to generate members of the sequence is to modify a routine used to change the base of an integer:
>>> def base10change(n, base):
digits = []
while n:
n,remainder = divmod(n, base)
digits.insert(0, remainder)
return digits
>>> base10change(11, 2)
[1, 0, 1, 1]
the above showing that 11 in decimal is
1
×
2
3
+
0
×
2
2
+
1
×
2
1
+
1
×
2
0
{\displaystyle 1\times 2^{3}+0\times 2^{2}+1\times 2^{1}+1\times 2^{0}}
.
Reflected this would become .1101 or
1
×
2
−
1
+
1
×
2
−
2
+
0
×
2
−
3
+
1
×
2
−
4
{\displaystyle 1\times 2^{-1}+1\times 2^{-2}+0\times 2^{-3}+1\times 2^{-4}}
Task description
Create a function/method/routine that given n, generates the n'th term of the van der Corput sequence in base 2.
Use the function to compute and display the first ten members of the sequence. (The first member of the sequence is for n=0).
As a stretch goal/extra credit, compute and show members of the sequence for bases other than 2.
See also
The Basic Low Discrepancy Sequences
Non-decimal radices/Convert
Van der Corput sequence
| #jq | jq | # vdc(base) converts an input decimal integer to a decimal number based on the van der
# Corput sequence using base 'base', e.g. (4 | vdc(2)) is 0.125.
#
def vdc(base):
# The helper function converts a stream of residuals to a decimal,
# e.g. if base is 2, then decimalize( (0,0,1) ) yields 0.125
def decimalize(stream):
reduce stream as $d # state: [accumulator, power]
( [0, 1/base];
.[1] as $power | [ .[0] + ($d * $power), $power / base] )
| .[0];
if . == 0 then 0
else decimalize(recurse( if . == 0 then empty else ./base | floor end ) % base)
end ; |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
The encoded string "google.com/search?q=%60Abdu%27l-Bah%C3%A1" should revert to the unencoded form "google.com/search?q=`Abdu'l-Bahá".
| #Delphi | Delphi | program URLEncoding;
{$APPTYPE CONSOLE}
uses IdURI;
begin
Writeln(TIdURI.URLDecode('http%3A%2F%2Ffoo%20bar%2F'));
end. |
http://rosettacode.org/wiki/URL_decoding | URL decoding | This task (the reverse of URL encoding and distinct from URL parser) is to provide a function
or mechanism to convert an URL-encoded string into its original unencoded form.
Test cases
The encoded string "http%3A%2F%2Ffoo%20bar%2F" should be reverted to the unencoded form "http://foo bar/".
The encoded string "google.com/search?q=%60Abdu%27l-Bah%C3%A1" should revert to the unencoded form "google.com/search?q=`Abdu'l-Bahá".
| #Elixir | Elixir | IO.inspect URI.decode("http%3A%2F%2Ffoo%20bar%2F")
IO.inspect URI.decode("google.com/search?q=%60Abdu%27l-Bah%C3%A1") |
http://rosettacode.org/wiki/UPC | UPC | Goal
Convert UPC bar codes to decimal.
Specifically:
The UPC standard is actually a collection of standards -- physical standards, data format standards, product reference standards...
Here, in this task, we will focus on some of the data format standards, with an imaginary physical+electrical implementation which converts physical UPC bar codes to ASCII (with spaces and # characters representing the presence or absence of ink).
Sample input
Below, we have a representation of ten different UPC-A bar codes read by our imaginary bar code reader:
# # # ## # ## # ## ### ## ### ## #### # # # ## ## # # ## ## ### # ## ## ### # # #
# # # ## ## # #### # # ## # ## # ## # # # ### # ### ## ## ### # # ### ### # # #
# # # # # ### # # # # # # # # # # ## # ## # ## # ## # # #### ### ## # #
# # ## ## ## ## # # # # ### # ## ## # # # ## ## # ### ## ## # # #### ## # # #
# # ### ## # ## ## ### ## # ## # # ## # # ### # ## ## # # ### # ## ## # # #
# # # # ## ## # # # # ## ## # # # # # #### # ## # #### #### # # ## # #### # #
# # # ## ## # # ## ## # ### ## ## # # # # # # # # ### # # ### # # # # #
# # # # ## ## # # ## ## ### # # # # # ### ## ## ### ## ### ### ## # ## ### ## # #
# # ### ## ## # # #### # ## # #### # #### # # # # # ### # # ### # # # ### # # #
# # # #### ## # #### # # ## ## ### #### # # # # ### # ### ### # # ### # # # ### # #
Some of these were entered upside down, and one entry has a timing error.
Task
Implement code to find the corresponding decimal representation of each, rejecting the error.
Extra credit for handling the rows entered upside down (the other option is to reject them).
Notes
Each digit is represented by 7 bits:
0: 0 0 0 1 1 0 1
1: 0 0 1 1 0 0 1
2: 0 0 1 0 0 1 1
3: 0 1 1 1 1 0 1
4: 0 1 0 0 0 1 1
5: 0 1 1 0 0 0 1
6: 0 1 0 1 1 1 1
7: 0 1 1 1 0 1 1
8: 0 1 1 0 1 1 1
9: 0 0 0 1 0 1 1
On the left hand side of the bar code a space represents a 0 and a # represents a 1.
On the right hand side of the bar code, a # represents a 0 and a space represents a 1
Alternatively (for the above): spaces always represent zeros and # characters always represent ones, but the representation is logically negated -- 1s and 0s are flipped -- on the right hand side of the bar code.
The UPC-A bar code structure
It begins with at least 9 spaces (which our imaginary bar code reader unfortunately doesn't always reproduce properly),
then has a # # sequence marking the start of the sequence,
then has the six "left hand" digits,
then has a # # sequence in the middle,
then has the six "right hand digits",
then has another # # (end sequence), and finally,
then ends with nine trailing spaces (which might be eaten by wiki edits, and in any event, were not quite captured correctly by our imaginary bar code reader).
Finally, the last digit is a checksum digit which may be used to help detect errors.
Verification
Multiply each digit in the represented 12 digit sequence by the corresponding number in (3,1,3,1,3,1,3,1,3,1,3,1) and add the products.
The sum (mod 10) must be 0 (must have a zero as its last digit) if the UPC number has been read correctly.
| #AutoHotkey | AutoHotkey | UPC2Dec(code){
lBits :={" ## #":0," ## #":1," # ##":2," #### #":3," # ##":4," ## #":5," # ####":6," ### ##":7," ## ###":8," # ##":9}
xlBits:={"# ## ":0,"# ## ":1,"## # ":2,"# #### ":3,"## # ":4,"# ## ":5,"#### # ":6,"## ### ":7,"### ## ":8,"## # ":9}
rBits :={"### # ":0,"## ## ":1,"## ## ":2,"# # ":3,"# ### ":4,"# ### ":5,"# # ":6,"# # ":7,"# # ":8,"### # ":9}
xrBits:={" # ###":0," ## ##":1," ## ##":2," # #":3," ### #":4," ### #":5," # #":6," # #":7," # #":8," # ###":9}
UPC := "", CD := 0, code := Trim(code, " ")
S := SubStr(code, 1, 3), code := SubStr(code, 4) ; start or "upside down" end sequence
loop 6
C := SubStr(code, 1, 7), code := SubStr(code, 8) ; six left hand or "upside down" right hand digits
, UPC := lBits[C] <> "" ? UPC . lBits[C] : xrBits[C] . UPC
M := SubStr(code, 1, 5), code := SubStr(code, 6) ; middle sequence
loop 6
C := SubStr(code, 1, 7), code := SubStr(code, 8) ; six right hand or "upside down" left hand digits
, UPC := rBits[C] <> "" ? UPC . rBits[C] : xlBits[C] . UPC
E := SubStr(code, 1, 3), code := SubStr(code, 4) ; end or "upside down" start sequence
for k, v in StrSplit(UPC)
CD += Mod(A_Index, 2) ? v*3 : v ; Check Digit
if (S <> "# #") || (M <> " # # ") || (E <> "# #") || Mod(CD, 10)
return "Invalid!"
return UPC
}
|
http://rosettacode.org/wiki/Update_a_configuration_file | Update a configuration file | We have a configuration file as follows:
# This is a configuration file in standard configuration file format
#
# Lines begininning with a hash or a semicolon are ignored by the application
# program. Blank lines are also ignored by the application program.
# The first word on each non comment line is the configuration option.
# Remaining words or numbers on the line are configuration parameter
# data fields.
# Note that configuration option names are not case sensitive. However,
# configuration parameter data is case sensitive and the lettercase must
# be preserved.
# This is a favourite fruit
FAVOURITEFRUIT banana
# This is a boolean that should be set
NEEDSPEELING
# This boolean is commented out
; SEEDSREMOVED
# How many bananas we have
NUMBEROFBANANAS 48
The task is to manipulate the configuration file as follows:
Disable the needspeeling option (using a semicolon prefix)
Enable the seedsremoved option by removing the semicolon and any leading whitespace
Change the numberofbananas parameter to 1024
Enable (or create if it does not exist in the file) a parameter for numberofstrawberries with a value of 62000
Note that configuration option names are not case sensitive. This means that changes should be effected, regardless of the case.
Options should always be disabled by prefixing them with a semicolon.
Lines beginning with hash symbols should not be manipulated and left unchanged in the revised file.
If a configuration option does not exist within the file (in either enabled or disabled form), it should be added during this update. Duplicate configuration option names in the file should be removed, leaving just the first entry.
For the purpose of this task, the revised file should contain appropriate entries, whether enabled or not for needspeeling,seedsremoved,numberofbananas and numberofstrawberries.)
The update should rewrite configuration option names in capital letters. However lines beginning with hashes and any parameter data must not be altered (eg the banana for favourite fruit must not become capitalized). The update process should also replace double semicolon prefixes with just a single semicolon (unless it is uncommenting the option, in which case it should remove all leading semicolons).
Any lines beginning with a semicolon or groups of semicolons, but no following option should be removed, as should any leading or trailing whitespace on the lines. Whitespace between the option and parameters should consist only of a single
space, and any non-ASCII extended characters, tabs characters, or control codes
(other than end of line markers), should also be removed.
Related tasks
Read a configuration file
| #FreeBASIC | FreeBASIC | ' FB 1.05.0 Win64
Type ConfigData
favouriteFruit As String
needsPeeling As Boolean
seedsRemoved As Boolean
numberOfBananas As UInteger
numberOfStrawberries As UInteger
End Type
Sub updateConfigData(fileName As String, cData As ConfigData)
Dim fileNum As Integer = FreeFile
Open fileName For Input As #fileNum
If err > 0 Then
Print "File could not be opened"
Sleep
End
End If
Dim tempFileName As String = "temp_" + fileName
Dim fileNum2 As Integer = FreeFile
Open tempFileName For Output As #fileNum2
Dim As Boolean hadFruit, hadPeeling, hadSeeds, hadBananas, hadStrawberries '' all false by default
Dim As String ln
While Not Eof(fileNum)
Line Input #fileNum, ln
If ln = "" OrElse Left(ln, 1) = "#" Then
Print #fileNum2, ln
Continue While
End If
ln = Trim(LTrim(ln, ";"), Any !" \t")
If ln = "" Then Continue While
If UCase(Left(ln, 14)) = "FAVOURITEFRUIT" Then
If hadFruit Then Continue While
hadFruit = True
Print #fileNum2, "FAVOURITEFRUIT " + cData.favouriteFruit
ElseIf UCase(Left(ln, 12)) = "NEEDSPEELING" Then
If hadPeeling Then Continue While
hadPeeling = True
If cData.needsPeeling Then
Print #fileNum2, "NEEDSPEELING"
Else
Print #fileNum2, "; NEEDSPEELING"
End If
ElseIf UCase(Left(ln, 12)) = "SEEDSREMOVED" Then
If hadSeeds Then Continue While
hadSeeds = True
If cData.seedsRemoved Then
Print #fileNum2, "SEEDSREMOVED"
Else
Print #fileNum2, "; SEEDSREMOVED"
End If
ElseIf UCase(Left(ln, 15)) = "NUMBEROFBANANAS" Then
If hadBananas Then Continue While
hadBananas = True
Print #fileNum2, "NUMBEROFBANANAS " + Str(cData.numberOfBananas)
ElseIf UCase(Left(ln, 20)) = "NUMBEROFSTRAWBERRIES" Then
If hadStrawberries Then Continue While
hadStrawberries = True
Print #fileNum2, "NUMBEROFSTRAWBERRIES " + Str(cData.numberOfStrawBerries)
End If
Wend
If Not hadFruit Then
Print #fileNum2, "FAVOURITEFRUIT " + cData.favouriteFruit
End If
If Not hadPeeling Then
If cData.needsPeeling Then
Print #fileNum2, "NEEDSPEELING"
Else
Print #fileNum2, "; NEEDSPEELING"
End If
End If
If Not hadSeeds Then
If cData.seedsRemoved Then
Print #fileNum2, "SEEDSREMOVED"
Else
Print #fileNum2, "; SEEDSREMOVED"
End If
End If
If Not hadBananas Then
Print #fileNum2, "NUMBEROFBANANAS " + Str(cData.numberOfBananas)
End If
If Not hadStrawberries Then
Print #fileNum2, "NUMBEROFSTRAWBERRIES " + Str(cData.numberOfStrawBerries)
End If
Close #fileNum : Close #fileNum2
Kill(fileName)
Name (tempFileName fileName)
End Sub
Dim fileName As String = "config2.txt"
Dim cData As ConfigData
With cData
.favouriteFruit = "banana"
.needsPeeling = False
.seedsRemoved = True
.numberOfBananas = 1024
.numberOfStrawberries = 62000
End With
updateConfigData fileName, cData
Print
Print "Press any key to quit"
Sleep |
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
| #COBOL | COBOL | IDENTIFICATION DIVISION.
PROGRAM-ID. Get-Input.
DATA DIVISION.
WORKING-STORAGE SECTION.
01 Input-String PIC X(30).
01 Input-Int PIC 9(5).
PROCEDURE DIVISION.
DISPLAY "Enter a string:"
ACCEPT Input-String
DISPLAY "Enter a number:"
ACCEPT Input-Int
GOBACK
. |
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
| #Common_Lisp | Common Lisp | (format t "Enter some text: ")
(let ((s (read-line)))
(format t "You entered ~s~%" s))
(format t "Enter a number: ")
(let ((n (read)))
(if (numberp n)
(format t "You entered ~d.~%" n)
(format t "That was not a number."))) |
http://rosettacode.org/wiki/User_input/Graphical | User input/Graphical |
In this task, the goal is to input a string and the integer 75000, from graphical user interface.
See also: User input/Text
| #Go | Go | package main
import (
"github.com/gotk3/gotk3/gtk"
"log"
"math/rand"
"strconv"
"time"
)
func validateInput(window *gtk.Window, str1, str2 string) bool {
n, err := strconv.ParseFloat(str2, 64)
if len(str1) == 0 || err != nil || n != 75000 {
dialog := gtk.MessageDialogNew(
window,
gtk.DIALOG_MODAL,
gtk.MESSAGE_ERROR,
gtk.BUTTONS_OK,
"Invalid input",
)
dialog.Run()
dialog.Destroy()
return false
}
return true
}
func check(err error, msg string) {
if err != nil {
log.Fatal(msg, err)
}
}
func main() {
rand.Seed(time.Now().UnixNano())
gtk.Init(nil)
window, err := gtk.WindowNew(gtk.WINDOW_TOPLEVEL)
check(err, "Unable to create window:")
window.SetTitle("Rosetta Code")
window.SetPosition(gtk.WIN_POS_CENTER)
window.Connect("destroy", func() {
gtk.MainQuit()
})
vbox, err := gtk.BoxNew(gtk.ORIENTATION_VERTICAL, 1)
check(err, "Unable to create vertical box:")
vbox.SetBorderWidth(1)
hbox1, err := gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, 1)
check(err, "Unable to create first horizontal box:")
hbox2, err := gtk.BoxNew(gtk.ORIENTATION_HORIZONTAL, 1)
check(err, "Unable to create second horizontal box:")
label, err := gtk.LabelNew("Enter a string and the number 75000 \n")
check(err, "Unable to create label:")
sel, err := gtk.LabelNew("String: ")
check(err, "Unable to create string entry label:")
nel, err := gtk.LabelNew("Number: ")
check(err, "Unable to create number entry label:")
se, err := gtk.EntryNew()
check(err, "Unable to create string entry:")
ne, err := gtk.EntryNew()
check(err, "Unable to create number entry:")
hbox1.PackStart(sel, false, false, 2)
hbox1.PackStart(se, false, false, 2)
hbox2.PackStart(nel, false, false, 2)
hbox2.PackStart(ne, false, false, 2)
// button to accept
ab, err := gtk.ButtonNewWithLabel("Accept")
check(err, "Unable to create accept button:")
ab.Connect("clicked", func() {
// read and validate the entered values
str1, _ := se.GetText()
str2, _ := ne.GetText()
if validateInput(window, str1, str2) {
window.Destroy() // close window if input is OK
}
})
vbox.Add(label)
vbox.Add(hbox1)
vbox.Add(hbox2)
vbox.Add(ab)
window.Add(vbox)
window.ShowAll()
gtk.Main()
} |
http://rosettacode.org/wiki/UTF-8_encode_and_decode | UTF-8 encode and decode | As described in UTF-8 and in Wikipedia, UTF-8 is a popular encoding of (multi-byte) Unicode code-points into eight-bit octets.
The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1-4 bytes representing that character in the UTF-8 encoding.
Then you have to write the corresponding decoder that takes a sequence of 1-4 UTF-8 encoded bytes and return the corresponding unicode character.
Demonstrate the functionality of your encoder and decoder on the following five characters:
Character Name Unicode UTF-8 encoding (hex)
---------------------------------------------------------------------------------
A LATIN CAPITAL LETTER A U+0041 41
ö LATIN SMALL LETTER O WITH DIAERESIS U+00F6 C3 B6
Ж CYRILLIC CAPITAL LETTER ZHE U+0416 D0 96
€ EURO SIGN U+20AC E2 82 AC
𝄞 MUSICAL SYMBOL G CLEF U+1D11E F0 9D 84 9E
Provided below is a reference implementation in Common Lisp.
| #Groovy | Groovy | import java.nio.charset.StandardCharsets
class UTF8EncodeDecode {
static byte[] utf8encode(int codePoint) {
char[] characters = [codePoint]
new String(characters, 0, 1).getBytes StandardCharsets.UTF_8
}
static int utf8decode(byte[] bytes) {
new String(bytes, StandardCharsets.UTF_8).codePointAt(0)
}
static void main(String[] args) {
printf "%-7s %-43s %7s\t%s\t%7s%n", "Char", "Name", "Unicode", "UTF-8 encoded", "Decoded"
([0x0041, 0x00F6, 0x0416, 0x20AC, 0x1D11E]).each { int codePoint ->
byte[] encoded = utf8encode codePoint
Formatter formatter = new Formatter()
encoded.each { byte b ->
formatter.format "%02X ", b
}
String encodedHex = formatter.toString()
int decoded = utf8decode encoded
printf "%-7c %-43s U+%04X\t%-12s\tU+%04X%n", codePoint, Character.getName(codePoint), codePoint, encodedHex, decoded
}
}
} |
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a 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.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (int argc, char * argv [])
{
char Buffer [1024];
size_t Size = sizeof (Buffer);
if (0 == Query (Buffer, &Size))
{
printf ("failed to call Query\n");
}
else
{
char * Ptr = Buffer;
while (Size-- > 0) putchar (*Ptr++);
putchar ('\n');
}
}
Implement the missing Query function in your language, and let this C program call it. The function should place the string Here am I into the buffer which is passed to it as the parameter Data. The buffer size in bytes is passed as the parameter Length. When there is no room in the buffer, Query shall return 0. Otherwise it overwrites the beginning of Buffer, sets the number of overwritten bytes into Length and returns 1.
| #PicoLisp | PicoLisp | (let (Str "Here am I" Len (format (opt))) # Get length from command line
(unless (>= (size Str) Len) # Check buffer size
(prinl Str) ) ) # Return string if OK |
http://rosettacode.org/wiki/Use_another_language_to_call_a_function | Use another language to call a 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.
This task is inverse to the task Call foreign language function. Consider the following C program:
#include <stdio.h>
extern int Query (char * Data, size_t * Length);
int main (int argc, char * argv [])
{
char Buffer [1024];
size_t Size = sizeof (Buffer);
if (0 == Query (Buffer, &Size))
{
printf ("failed to call Query\n");
}
else
{
char * Ptr = Buffer;
while (Size-- > 0) putchar (*Ptr++);
putchar ('\n');
}
}
Implement the missing Query function in your language, and let this C program call it. The function should place the string Here am I into the buffer which is passed to it as the parameter Data. The buffer size in bytes is passed as the parameter Length. When there is no room in the buffer, Query shall return 0. Otherwise it overwrites the beginning of Buffer, sets the number of overwritten bytes into Length and returns 1.
| #Python | Python |
# store this in file rc_embed.py
# store this in file rc_embed.py
def query(buffer_length):
message = b'Here am I'
L = len(message)
return message[0:L*(L <= buffer_length)]
|
http://rosettacode.org/wiki/URL_parser | URL parser | URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
According to the standards, the characters:
! * ' ( ) ; : @ & = + $ , / ? % # [ ]
only need to be percent-encoded (%) in case of possible confusion.
Also note that the path, query and fragment are case sensitive, even if the scheme and domain are not.
The way the returned information is provided (set of variables, array, structured, record, object,...)
is language-dependent and left to the programmer, but the code should be clear enough to reuse.
Extra credit is given for clear error diagnostics.
Here is the official standard: https://tools.ietf.org/html/rfc3986,
and here is a simpler BNF: http://www.w3.org/Addressing/URL/5_URI_BNF.html.
Test cases
According to T. Berners-Lee
foo://example.com:8042/over/there?name=ferret#nose should parse into:
scheme = foo
domain = example.com
port = :8042
path = over/there
query = name=ferret
fragment = nose
urn:example:animal:ferret:nose should parse into:
scheme = urn
path = example:animal:ferret:nose
other URLs that must be parsed include:
jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true
ftp://ftp.is.co.za/rfc/rfc1808.txt
http://www.ietf.org/rfc/rfc2396.txt#header1
ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two
mailto:[email protected]
news:comp.infosystems.www.servers.unix
tel:+1-816-555-1212
telnet://192.0.2.16:80/
urn:oasis:names:specification:docbook:dtd:xml:4.1.2
| #Nim | Nim | import uri, strformat
proc printUri(url: string) =
echo url
let res = parseUri(url)
if res.scheme != "":
echo &"\t Scheme: {res.scheme}"
if res.hostname != "":
echo &"\tHostname: {res.hostname}"
if res.username != "":
echo &"\tUsername: {res.username}"
if res.password != "":
echo &"\tPassword: {res.password}"
if res.path != "":
echo &"\t Path: {res.path}"
if res.query != "":
echo &"\t Query: {res.query}"
if res.port != "":
echo &"\t Port: {res.port}"
if res.anchor != "":
echo &"\t Anchor: {res.anchor}"
if res.opaque:
echo &"\t Opaque: {res.opaque}"
let urls = ["foo://example.com:8042/over/there?name=ferret#nose",
"urn:example:animal:ferret:nose",
"jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true",
"ftp://ftp.is.co.za/rfc/rfc1808.txt",
"http://www.ietf.org/rfc/rfc2396.txt#header1",
"ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two",
"mailto:[email protected]",
"news:comp.infosystems.www.servers.unix",
"tel:+1-816-555-1212",
"telnet://192.0.2.16:80/",
"urn:oasis:names:specification:docbook:dtd:xml:4.1.2",
"ssh://[email protected]",
"https://bob:[email protected]/place",
"http://example.com/?a=1&b=2+2&c=3&c=4&d=%65%6e%63%6F%64%65%64"]
for url in urls:
printUri(url) |
http://rosettacode.org/wiki/URL_parser | URL parser | URLs are strings with a simple syntax:
scheme://[username:password@]domain[:port]/path?query_string#fragment_id
Task
Parse a well-formed URL to retrieve the relevant information: scheme, domain, path, ...
Note: this task has nothing to do with URL encoding or URL decoding.
According to the standards, the characters:
! * ' ( ) ; : @ & = + $ , / ? % # [ ]
only need to be percent-encoded (%) in case of possible confusion.
Also note that the path, query and fragment are case sensitive, even if the scheme and domain are not.
The way the returned information is provided (set of variables, array, structured, record, object,...)
is language-dependent and left to the programmer, but the code should be clear enough to reuse.
Extra credit is given for clear error diagnostics.
Here is the official standard: https://tools.ietf.org/html/rfc3986,
and here is a simpler BNF: http://www.w3.org/Addressing/URL/5_URI_BNF.html.
Test cases
According to T. Berners-Lee
foo://example.com:8042/over/there?name=ferret#nose should parse into:
scheme = foo
domain = example.com
port = :8042
path = over/there
query = name=ferret
fragment = nose
urn:example:animal:ferret:nose should parse into:
scheme = urn
path = example:animal:ferret:nose
other URLs that must be parsed include:
jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true
ftp://ftp.is.co.za/rfc/rfc1808.txt
http://www.ietf.org/rfc/rfc2396.txt#header1
ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two
mailto:[email protected]
news:comp.infosystems.www.servers.unix
tel:+1-816-555-1212
telnet://192.0.2.16:80/
urn:oasis:names:specification:docbook:dtd:xml:4.1.2
| #Objeck | Objeck | use Web.HTTP;
class Test {
function : Main(args : String[]) ~ Nil {
urls := [
"foo://example.com:8042/over/there?name=ferret#nose",
"urn:example:animal:ferret:nose",
"jdbc:mysql://test_user:ouupppssss@localhost:3306/sakila?profileSQL=true",
"ftp://ftp.is.co.za/rfc/rfc1808.txt",
"http://www.ietf.org/rfc/rfc2396.txt#header1",
"ldap://[2001:db8::7]/c=GB?objectClass=one&objectClass=two",
"mailto:[email protected]",
"news:comp.infosystems.www.servers.unix",
"tel:+1-816-555-1212",
"telnet://192.0.2.16:80/",
"urn:oasis:names:specification:docbook:dtd:xml:4.1.2",
"http://example.com/?a=1&b=2+2&c=3&c=4&d=%65%6e%63%6F%64%65%64:"];
each(i : urls) {
url := Url->New(urls[i]);
if(url->Parsed()) {
url->ToString()->PrintLine();
};
};
}
} |
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #Frink | Frink | println[URLEncode["http://foo bar/"]] |
http://rosettacode.org/wiki/URL_encoding | URL encoding | Task
Provide a function or mechanism to convert a provided string into URL encoding representation.
In URL encoding, special characters, control characters and extended characters
are converted into a percent symbol followed by a two digit hexadecimal code,
So a space character encodes into %20 within the string.
For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:
ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
Extended characters with character codes of 128 decimal (80 hex) and above.
Example
The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".
Variations
Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.
Options
It is permissible to use an exception string (containing a set of symbols
that do not need to be converted).
However, this is an optional feature and is not a requirement of this task.
Related tasks
URL decoding
URL parser
| #Go | Go | package main
import (
"fmt"
"net/url"
)
func main() {
fmt.Println(url.QueryEscape("http://foo bar/"))
} |
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #Eiffel | Eiffel |
class
APPLICATION
inherit
ARGUMENTS
create
make
feature {NONE} -- Initialization
make
-- Run application.
local
i: INTEGER
s: STRING
do
i := 100
s := "Some string"
create a.make_empty
end
feature {NONE} -- Class Features
a: ARRAY[INTEGER]
|
http://rosettacode.org/wiki/Variables | Variables | Task
Demonstrate a language's methods of:
variable declaration
initialization
assignment
datatypes
scope
referencing, and
other variable related facilities
| #Ela | Ela | x = 42
sum x y = x + y |
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 A:
0
Using B:
0 0
Using C:
0 0 1
Using B:
0 0 1 0
Using C: (zero last occurred two steps back - before the one)
0 0 1 0 2
Using B:
0 0 1 0 2 0
Using C: (two last occurred two steps back - before the zero)
0 0 1 0 2 0 2 2
Using C: (two last occurred one step back)
0 0 1 0 2 0 2 2 1
Using C: (one last appeared six steps back)
0 0 1 0 2 0 2 2 1 6
...
Task
Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
Use it to display here, on this page:
The first ten terms of the sequence.
Terms 991 - to - 1000 of the sequence.
References
Don't Know (the Van Eck Sequence) - Numberphile video.
Wikipedia Article: Van Eck's Sequence.
OEIS sequence: A181391.
| #jq | jq | # Input: an array
# If the rightmost element, .[-1], does not occur elsewhere, return 0;
# otherwise return the "depth" of its rightmost occurrence in .[0:-2]
def depth:
.[-1] as $x
| length as $length
| first(range($length-2; -1; -1) as $i
| select(.[$i] == $x) | $length - 1 - $i)
// 0 ;
# Generate a stream of the first $n van Eck integers:
def vanEck($n):
def v:
recurse( if length == $n then empty
else . + [depth] end );
[0] | v | .[-1];
# The task:
[vanEck(10)], [vanEck(1000)][990:1001]
|
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 A:
0
Using B:
0 0
Using C:
0 0 1
Using B:
0 0 1 0
Using C: (zero last occurred two steps back - before the one)
0 0 1 0 2
Using B:
0 0 1 0 2 0
Using C: (two last occurred two steps back - before the zero)
0 0 1 0 2 0 2 2
Using C: (two last occurred one step back)
0 0 1 0 2 0 2 2 1
Using C: (one last appeared six steps back)
0 0 1 0 2 0 2 2 1 6
...
Task
Create a function/procedure/method/subroutine/... to generate the Van Eck sequence of numbers.
Use it to display here, on this page:
The first ten terms of the sequence.
Terms 991 - to - 1000 of the sequence.
References
Don't Know (the Van Eck Sequence) - Numberphile video.
Wikipedia Article: Van Eck's Sequence.
OEIS sequence: A181391.
| #Julia | Julia | function vanecksequence(N, startval=0)
ret = zeros(Int, N)
ret[1] = startval
for i in 1:N-1
lastseen = findlast(x -> x == ret[i], ret[1:i-1])
if lastseen != nothing
ret[i + 1] = i - lastseen
end
end
ret
end
println(vanecksequence(10))
println(vanecksequence(1000)[991:1000])
|
http://rosettacode.org/wiki/Vampire_number | Vampire number | A vampire number is a natural decimal number with an even number of digits, that can be factored into two integers.
These two factors are called the fangs, and must have the following properties:
they each contain half the number of the decimal digits of the original number
together they consist of exactly the same decimal digits as the original number
at most one of them has a trailing zero
An example of a vampire number and its fangs: 1260 : (21, 60)
Task
Print the first 25 vampire numbers and their fangs.
Check if the following numbers are vampire numbers and, if so, print them and their fangs:
16758243290880, 24959017348650, 14593825548650
Note that a vampire number can have more than one pair of fangs.
See also
numberphile.com.
vampire search algorithm
vampire numbers on OEIS
| #Python | Python | from __future__ import division
import math
from operator import mul
from itertools import product
from functools import reduce
def fac(n):
'''\
return the prime factors for n
>>> fac(600)
[5, 5, 3, 2, 2, 2]
>>> fac(1000)
[5, 5, 5, 2, 2, 2]
>>>
'''
step = lambda x: 1 + x*4 - (x//2)*2
maxq = int(math.floor(math.sqrt(n)))
d = 1
q = n % 2 == 0 and 2 or 3
while q <= maxq and n % q != 0:
q = step(d)
d += 1
res = []
if q <= maxq:
res.extend(fac(n//q))
res.extend(fac(q))
else: res=[n]
return res
def fact(n):
'''\
return the prime factors and their multiplicities for n
>>> fact(600)
[(2, 3), (3, 1), (5, 2)]
>>> fact(1000)
[(2, 3), (5, 3)]
>>>
'''
res = fac(n)
return [(c, res.count(c)) for c in set(res)]
def divisors(n):
'Returns all the divisors of n'
factors = fact(n) # [(primefactor, multiplicity), ...]
primes, maxpowers = zip(*factors)
powerranges = (range(m+1) for m in maxpowers)
powers = product(*powerranges)
return (
reduce(mul,
(prime**power for prime, power in zip(primes, powergroup)),
1)
for powergroup in powers)
def vampire(n):
fangsets = set( frozenset([d, n//d])
for d in divisors(n)
if (len(str(d)) == len(str(n))/2.
and sorted(str(d) + str(n//d)) == sorted(str(n))
and (str(d)[-1] == 0) + (str(n//d)[-1] == 0) <=1) )
return sorted(tuple(sorted(fangs)) for fangs in fangsets)
if __name__ == '__main__':
print('First 25 vampire numbers')
count = n = 0
while count <25:
n += 1
fangpairs = vampire(n)
if fangpairs:
count += 1
print('%i: %r' % (n, fangpairs))
print('\nSpecific checks for fangpairs')
for n in (16758243290880, 24959017348650, 14593825548650):
fangpairs = vampire(n)
print('%i: %r' % (n, fangpairs)) |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #Modula-3 | Modula-3 | MODULE Varargs EXPORTS Main;
IMPORT IO;
VAR strings := ARRAY [1..5] OF TEXT {"foo", "bar", "baz", "quux", "zeepf"};
PROCEDURE Variable(VAR arr: ARRAY OF TEXT) =
BEGIN
FOR i := FIRST(arr) TO LAST(arr) DO
IO.Put(arr[i] & "\n");
END;
END Variable;
BEGIN
Variable(strings);
END Varargs. |
http://rosettacode.org/wiki/Variadic_function | Variadic function | Task
Create a function which takes in a variable number of arguments and prints each one on its own line.
Also show, if possible in your language, how to call the function on a list of arguments constructed at runtime.
Functions of this type are also known as Variadic Functions.
Related task
Call a function
| #Nemerle | Nemerle | using System;
using System.Console;
module Variadic
{
PrintAll (params args : array[object]) : void
{
foreach (arg in args) WriteLine(arg);
}
Main() : void
{
PrintAll("test", "rosetta code", 123, 5.6, DateTime.Now);
}
} |
http://rosettacode.org/wiki/Vector | Vector | Task
Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented.
The Vector may be initialized in any reasonable way.
Start and end points, and direction
Angular coefficient and value (length)
The four operations to be implemented are:
Vector + Vector addition
Vector - Vector subtraction
Vector * scalar multiplication
Vector / scalar division
| #VBA | VBA | Type vector
x As Double
y As Double
End Type
Type vector2
phi As Double
r As Double
End Type
Private Function vector_addition(u As vector, v As vector) As vector
vector_addition.x = u.x + v.x
vector_addition.y = u.y + v.y
End Function
Private Function vector_subtraction(u As vector, v As vector) As vector
vector_subtraction.x = u.x - v.x
vector_subtraction.y = u.y - v.y
End Function
Private Function scalar_multiplication(u As vector, v As Double) As vector
scalar_multiplication.x = u.x * v
scalar_multiplication.y = u.y * v
End Function
Private Function scalar_division(u As vector, v As Double) As vector
scalar_division.x = u.x / v
scalar_division.y = u.y / v
End Function
Private Function to_cart(v2 As vector2) As vector
to_cart.x = v2.r * Cos(v2.phi)
to_cart.y = v2.r * Sin(v2.phi)
End Function
Private Sub display(u As vector)
Debug.Print "( " & Format(u.x, "0.000") & "; " & Format(u.y, "0.000") & ")";
End Sub
Public Sub main()
Dim a As vector, b As vector, c As vector2, d As Double
c.phi = WorksheetFunction.Pi() / 3
c.r = 5
d = 10
a = to_cart(c)
b.x = 1: b.y = -2
Debug.Print "addition : ";: display a: Debug.Print "+";: display b
Debug.Print "=";: display vector_addition(a, b): Debug.Print
Debug.Print "subtraction : ";: display a: Debug.Print "-";: display b
Debug.Print "=";: display vector_subtraction(a, b): Debug.Print
Debug.Print "scalar multiplication: ";: display a: Debug.Print " *";: Debug.Print d;
Debug.Print "=";: display scalar_multiplication(a, d): Debug.Print
Debug.Print "scalar division : ";: display a: Debug.Print " /";: Debug.Print d;
Debug.Print "=";: display scalar_division(a, d)
End Sub |
http://rosettacode.org/wiki/Vector | Vector | Task
Implement a Vector class (or a set of functions) that models a Physical Vector. The four basic operations and a pretty print function should be implemented.
The Vector may be initialized in any reasonable way.
Start and end points, and direction
Angular coefficient and value (length)
The four operations to be implemented are:
Vector + Vector addition
Vector - Vector subtraction
Vector * scalar multiplication
Vector / scalar division
| #Visual_Basic_.NET | Visual Basic .NET | Module Module1
Class Vector
Public store As Double()
Public Sub New(init As IEnumerable(Of Double))
store = init.ToArray()
End Sub
Public Sub New(x As Double, y As Double)
store = {x, y}
End Sub
Public Overloads Shared Operator +(v1 As Vector, v2 As Vector)
Return New Vector(v1.store.Zip(v2.store, Function(a, b) a + b))
End Operator
Public Overloads Shared Operator -(v1 As Vector, v2 As Vector)
Return New Vector(v1.store.Zip(v2.store, Function(a, b) a - b))
End Operator
Public Overloads Shared Operator *(v1 As Vector, scalar As Double)
Return New Vector(v1.store.Select(Function(x) x * scalar))
End Operator
Public Overloads Shared Operator /(v1 As Vector, scalar As Double)
Return New Vector(v1.store.Select(Function(x) x / scalar))
End Operator
Public Overrides Function ToString() As String
Return String.Format("[{0}]", String.Join(",", store))
End Function
End Class
Sub Main()
Dim v1 As New Vector(5, 7)
Dim v2 As New Vector(2, 3)
Console.WriteLine(v1 + v2)
Console.WriteLine(v1 - v2)
Console.WriteLine(v1 * 11)
Console.WriteLine(v1 / 2)
' Works with arbitrary size vectors, too.
Dim lostVector As New Vector({4, 8, 15, 16, 23, 42})
Console.WriteLine(lostVector * 7)
End Sub
End Module |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar cipher
Rot-13
Substitution Cipher
| #Swift | Swift | public func convertToUnicodeScalars(
str: String,
minChar: UInt32,
maxChar: UInt32
) -> [UInt32] {
var scalars = [UInt32]()
for scalar in str.unicodeScalars {
let val = scalar.value
guard val >= minChar && val <= maxChar else {
continue
}
scalars.append(val)
}
return scalars
}
public struct Vigenere {
private let keyScalars: [UInt32]
private let smallestScalar: UInt32
private let largestScalar: UInt32
private let sizeAlphabet: UInt32
public init?(key: String, smallestCharacter: Character = "A", largestCharacter: Character = "Z") {
let smallScalars = smallestCharacter.unicodeScalars
let largeScalars = largestCharacter.unicodeScalars
guard smallScalars.count == 1, largeScalars.count == 1 else {
return nil
}
self.smallestScalar = smallScalars.first!.value
self.largestScalar = largeScalars.first!.value
self.sizeAlphabet = (largestScalar - smallestScalar) + 1
let scalars = convertToUnicodeScalars(str: key, minChar: smallestScalar, maxChar: largestScalar)
guard !scalars.isEmpty else {
return nil
}
self.keyScalars = scalars
}
public func decrypt(_ str: String) -> String? {
let txtBytes = convertToUnicodeScalars(str: str, minChar: smallestScalar, maxChar: largestScalar)
guard !txtBytes.isEmpty else {
return nil
}
var res = ""
for (i, c) in txtBytes.enumerated() where c >= smallestScalar && c <= largestScalar {
guard let char =
UnicodeScalar((c &+ sizeAlphabet &- keyScalars[i % keyScalars.count]) % sizeAlphabet &+ smallestScalar)
else {
return nil
}
res += String(char)
}
return res
}
public func encrypt(_ str: String) -> String? {
let txtBytes = convertToUnicodeScalars(str: str, minChar: smallestScalar, maxChar: largestScalar)
guard !txtBytes.isEmpty else {
return nil
}
var res = ""
for (i, c) in txtBytes.enumerated() where c >= smallestScalar && c <= largestScalar {
guard let char =
UnicodeScalar((c &+ keyScalars[i % keyScalars.count] &- 2 &* smallestScalar) % sizeAlphabet &+ smallestScalar)
else {
return nil
}
res += String(char)
}
return res
}
}
let text = "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!";
let key = "VIGENERECIPHER";
let cipher = Vigenere(key: key)!
print("Key: \(key)")
print("Plain Text: \(text)")
let encoded = cipher.encrypt(text.uppercased())!
print("Cipher Text: \(encoded)")
let decoded = cipher.decrypt(encoded)!
print("Decoded: \(decoded)")
print("\nLarger set:")
let key2 = "Vigenère cipher"
let text2 = "This is a ünicode string 😃"
let cipher2 = Vigenere(key: key2, smallestCharacter: " ", largestCharacter: "🛹")!
print("Key: \(key2)")
print("Plain Text: \(text2)")
let encoded2 = cipher2.encrypt(text2)!
print("Cipher Text: \(encoded2)")
let decoded2 = cipher2.decrypt(encoded2)!
print("Decoded: \(decoded2)") |
http://rosettacode.org/wiki/Vigen%C3%A8re_cipher | Vigenère cipher | Task
Implement a Vigenère cypher, both encryption and decryption.
The program should handle keys and text of unequal length,
and should capitalize everything and discard non-alphabetic characters.
(If your program handles non-alphabetic characters in another way,
make a note of it.)
Related tasks
Caesar cipher
Rot-13
Substitution Cipher
| #Tcl | Tcl | package require Tcl 8.6
oo::class create Vigenere {
variable key
constructor {protoKey} {
foreach c [split $protoKey ""] {
if {[regexp {[A-Za-z]} $c]} {
lappend key [scan [string toupper $c] %c]
}
}
}
method encrypt {text} {
set out ""
set j 0
foreach c [split $text ""] {
if {[regexp {[^a-zA-Z]} $c]} continue
scan [string toupper $c] %c c
append out [format %c [expr {($c+[lindex $key $j]-130)%26+65}]]
set j [expr {($j+1) % [llength $key]}]
}
return $out
}
method decrypt {text} {
set out ""
set j 0
foreach c [split $text ""] {
if {[regexp {[^A-Z]} $c]} continue
scan $c %c c
append out [format %c [expr {($c-[lindex $key $j]+26)%26+65}]]
set j [expr {($j+1) % [llength $key]}]
}
return $out
}
} |
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