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http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#Pascal
Pascal
Program HofstadterQSequence (output);   const limit = 100000;   var q: array [1..limit] of longint; i, flips: longint;   begin q[1] := 1; q[2] := 1; for i := 3 to limit do q[i] := q[i - q[i - 1]] + q[i - q[i - 2]]; for i := 1 to 10 do write(q[i], ' '); writeln; writeln(q[1000]); flips := 0; ...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Anyways
Anyways
There was a guy called Hello World "Ow!" it said. That's all folks!
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#REXX
REXX
/*REXX program generates & displays primitive Heronian triangles by side length and area*/ parse arg N first area . /*obtain optional arguments from the CL*/ if N=='' | N=="," then N= 200 /*Not specified? Then use the default.*/ if first=='' | first=="," then first= 10 ...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#Elena
Elena
import extensions;   public program() { var first := (f => f()); var second := {"second"}; console.printLine(first(second)) }
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#Sidef
Sidef
var port = 8080; var protocol = Socket.getprotobyname("tcp");   var sock = (Socket.open(Socket.PF_INET, Socket.SOCK_STREAM, protocol) || die "couldn't open a socket: #{$!}"); # PF_INET to indicate that this socket will connect to the internet domain # SOCK_STREAM indicates a TCP stream, SOCK_DGRAM would indicate UD...
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#Smalltalk
Smalltalk
Smalltalk loadPackage:'stx:goodies/webServer'. "usually already loaded" |myServer service|   myServer := HTTPServer startServerOnPort:8082. service := HTTPPluggableActionService new. service register:[:request | self halt: 'debugging'. request reply:'<HTML><BODY><H1>Hello World</H1></BODY></HTML>...
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#Standard_ML
Standard ML
(* Assuming real type for coefficients and x *) fun horner coeffList x = foldr (fn (a, b) => a + b * x) (0.0) coeffList
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#Swift
Swift
func horner(coefs: [Double], x: Double) -> Double { return reduce(lazy(coefs).reverse(), 0) { $0 * x + $1 } }   println(horner([-19, 7, -4, 6], 3))
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#Tcl
Tcl
package require Tcl 8.5 proc horner {coeffs x} { set y 0 foreach c [lreverse $coeffs] { set y [expr { $y*$x+$c }] } return $y }
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#Scheme
Scheme
; Easter sunday. Result is a list '(month day) ; ; See: ; Jean Meeus, "Astronomical Formulae for Calculators", ; 4th edition, Willmann-Bell, 1988, p.31   (define (easter year) (let* ((a (remainder year 19)) (b (quotient year 100)) (c (remainder year 100)) (d (quotien...
http://rosettacode.org/wiki/Horizontal_sundial_calculations
Horizontal sundial calculations
Task Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location. For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit...
#XPL0
XPL0
inc c:\cxpl\codes; def Pi = 3.14159265358979323846, Deg2Rad = Pi/180.0, Rad2Deg = 180.0/Pi, Tab = $09; real Lat, SinLat, Long, Mer; real HA, HLA; \hour angle and hour line angle int H, T; \hour, time [Text(0, "Latitude: "); Lat:= RlIn(0); Text(0, "Longit...
http://rosettacode.org/wiki/Horizontal_sundial_calculations
Horizontal sundial calculations
Task Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location. For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit...
#zkl
zkl
//(degree measure)*Degrees => Radian measure //(radian measure)/Degrees => Degree measure const pi=(0.0).pi, toDeg=(0.0).pi/180;   latitude :=ask(0,"Enter latitude: ").toFloat(); longitude:=ask(1,"Enter longitude: ").toFloat(); meridian :=ask(2,"Enter legal meridian: ").toFloat();   sineLatitude:=(latitude * toDeg).sin...
http://rosettacode.org/wiki/Huffman_coding
Huffman coding
Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols. For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could just encode each letter wi...
#Wren
Wren
import "/queue" for PriorityQueue   class HuffmanTree { construct new(freq) { _freq = freq } freq { _freq } compareTo(tree) { _freq - tree.freq } }   class HuffmanLeaf is HuffmanTree { construct new (freq, val) { super(freq) _val = val } val { _val } }   class Huffman...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#Oz
Oz
  declare fun {GetPage Url} F = {New Open.file init(url:Url)} Contents = {F read(list:$ size:all)} in {F close} Contents end in {System.showInfo {GetPage "http://www.rosettacode.org"}}  
http://rosettacode.org/wiki/Hofstadter-Conway_$10,000_sequence
Hofstadter-Conway $10,000 sequence
The definition of the sequence is colloquially described as:   Starting with the list [1,1],   Take the last number in the list so far: 1, I'll call it x.   Count forward x places from the beginning of the list to find the first number to add (1)   Count backward x places from the end of the list to find the secon...
#X86_Assembly
X86 Assembly
; Hofstadter-Conway $10,000 sequence call a.memorization call Mallows_Number ; ECX is the $1000 # int3   a.memorization: ; skip [a] to make it one based mov [a+1*4],1 mov [a+2*4],1 mov ecx,3 @@: mov eax,ecx mov edx,[a+(ecx-1)*4] ; a[n-1] sub eax,edx ; n-a[n-1] mov eax,[...
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Swift
Swift
import Foundation   let out = NSOutputStream(toFileAtPath: "/dev/stderr", append: true) let err = "Goodbye, World!".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false) out?.open() let success = out?.write(UnsafePointer<UInt8>(err!.bytes), maxLength: err!.length) out?.close()   if let bytes = success { ...
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Tcl
Tcl
puts stderr "Goodbye, World!"
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Transact-SQL
Transact-SQL
RAISERROR 'Goodbye, World!', 16, 1
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#True_BASIC
True BASIC
  CAUSE error 1, "Goodbye World!" END  
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#TUSCRIPT
TUSCRIPT
  $$ MODE TUSCRIPT PRINT/ERROR "hello world" text="goodbye world" PRINT/ERROR text  
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#Perl
Perl
my @Q = (0,1,1); push @Q, $Q[-$Q[-1]] + $Q[-$Q[-2]] for 1..100_000; say "First 10 terms: [@Q[1..10]]"; say "Term 1000: $Q[1000]"; say "Terms less than preceding in first 100k: ",scalar(grep { $Q[$_] < $Q[$_-1] } 2..100000);
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#APL
APL
'Hello world!'
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Ring
Ring
  # Project : Heronian triangles   see "Heronian triangles with sides up to 200" + nl see "Sides Perimeter Area" + nl for n = 1 to 200 for m = n to 200 for p = m to 200 s = (n + m + p) / 2 w = sqrt(s * (s - n) * (s - m) * (s - p)) bool = (gcd(n, m) = 1 or ...
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Ruby
Ruby
class Triangle def self.valid?(a,b,c) # class method short, middle, long = [a, b, c].sort short + middle > long end   attr_reader :sides, :perimeter, :area   def initialize(a,b,c) @sides = [a, b, c].sort @perimeter = a + b + c s = @perimeter / 2.0 @area = Math.sqrt(s * (s - a) * (s ...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#Elixir
Elixir
iex(1)> defmodule RC do ...(1)> def first(f), do: f.() ...(1)> def second, do: :hello ...(1)> end {:module, RC, <<70, 79, 82, 49, 0, 0, 4, 224, 66, 69, 65, 77, 69, 120, 68, 99, 0, 0, 0, 142, 131, 104, 2, 100, 0, 14, 101, 108, 105, 120, 105, 114, 95, 100, 111, 99, 115, 95 , 118, 49, 108, 0, 0, 0, 2, 104, 2, ...>>, ...
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#Standard_ML
Standard ML
  val txt = Word8VectorSlice.full (Byte.stringToBytes "hello world!" ) ;   fun serve listener portnr = let fun next () = let val (conn, conn_addr) = Socket.accept listener in case Posix.Process.fork () of NONE => ( Socket.sendVec(conn, txt); Socket.close conn ; ...
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#Tcl
Tcl
proc accept {chan addr port} { while {[gets $chan] ne ""} {} puts $chan "HTTP/1.1 200 OK\nConnection: close\nContent-Type: text/plain\n" puts $chan "Goodbye, World!" close $chan } socket -server accept 8080 vwait forever
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#VBA
VBA
  Public Function Horner(x, ParamArray coeff()) Dim result As Double Dim ncoeff As Integer   result = 0 ncoeff = UBound(coeff())   For i = ncoeff To 0 Step -1 result = (result * x) + coeff(i) Next i Horner = result End Function  
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#VBScript
VBScript
  Function horners_rule(coefficients,x) accumulator = 0 For i = UBound(coefficients) To 0 Step -1 accumulator = (accumulator * x) + coefficients(i) Next horners_rule = accumulator End Function   WScript.StdOut.WriteLine horners_rule(Array(-19,7,-4,6),3)  
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#Seed7
Seed7
$ include "seed7_05.s7i"; include "time.s7i"; include "duration.s7i";   const func time: easterDate (in integer: year) is func result var time: result is time.value; local var integer: H1 is 0; var integer: H2 is 0; var integer: M is 0; var integer: N is 0; var integer: a is 0; var i...
http://rosettacode.org/wiki/Horizontal_sundial_calculations
Horizontal sundial calculations
Task Create a program that calculates the hour, sun hour angle, dial hour line angle from 6am to 6pm for an operator entered location. For example, the user is prompted for a location and inputs the latitude and longitude 4°57′S 150°30′W (4.95°S 150.5°W of Jules Verne's Lincoln Island, aka Ernest Legouve Reef), wit...
#ZX_Spectrum_Basic
ZX Spectrum Basic
10 DEF FN r(x)=x*PI/180 20 DEF FN d(x)=x*180/PI 30 INPUT "Enter latitude (degrees): ";latitude 40 INPUT "Enter longitude (degrees): ";longitude 50 INPUT "Enter legal meridian (degrees): ";meridian 60 PRINT "Latitude: ";latitude 70 PRINT "Longitude:";longitude 80 PRINT "Legal meridian: ";meridian 90 PRINT '" Sun ...
http://rosettacode.org/wiki/Huffman_coding
Huffman coding
Huffman encoding is a way to assign binary codes to symbols that reduces the overall number of bits used to encode a typical string of those symbols. For example, if you use letters as symbols and have details of the frequency of occurrence of those letters in typical strings, then you could just encode each letter wi...
#zkl
zkl
fcn buildHuffman(text){ //-->(encode dictionary, decode dictionary) ft:=Dictionary(); foreach c in (text){ ft[c]=ft.find(c,0)+1 } // leafs w/count   // build the tree, which is a list of lists of ... tree:=ft.pump(List,fcn([(c,cnt)]){ //-->L( (cnt, ((sym,code))), ...) L(cnt, L(L(c,""))) }).copy(...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#Pascal
Pascal
{$mode objfpc}{$H+} uses fphttpclient;   var s: string; hc: tfphttpclient;   begin hc := tfphttpclient.create(nil); try s := hc.get('http://www.example.com') finally hc.free end; writeln(s) end.
http://rosettacode.org/wiki/Hofstadter-Conway_$10,000_sequence
Hofstadter-Conway $10,000 sequence
The definition of the sequence is colloquially described as:   Starting with the list [1,1],   Take the last number in the list so far: 1, I'll call it x.   Count forward x places from the beginning of the list to find the first number to add (1)   Count backward x places from the end of the list to find the secon...
#zkl
zkl
fcn hofstadterConwaySequence(m){ a:=List.createLong(m + 1,0); a[0]=a[1]=1; v,p2,lg2, amax, mallow := a[2],4,1, 0.0, Void;   foreach n in ([2 .. m]){ v=a[n]=a[v] + a[n - v]; f:=1.0*v/n; if(f>=0.55) mallow=n; amax=amax.max(f); if(n==p2){ println("Max in [2^%d, 2^%d]: %f".fmt(lg...
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#UNIX_Shell
UNIX Shell
echo "Goodbye, World!" >&2
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Ursa
Ursa
out "goodbye, world!" endl console.err
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#VBA
VBA
  Sub StandardError() Debug.Print "Goodbye World!" End Sub  
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#VBScript
VBScript
WScript.StdErr.WriteLine "Goodbye, World!"
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Verbexx
Verbexx
@STDERR "Goodbye, World!\n";
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#Phix
Phix
with javascript_semantics sequence Q = {1,1} function q(integer n) integer l = length(Q) while n>l do l += 1 Q &= Q[l-Q[l-1]]+Q[l-Q[l-2]] end while return Q[n] end function {} = q(10) -- (or collect one by one) printf(1,"First ten terms: %v\n",{Q[1..10]}) printf(1,"1000th: %d...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#AppleScript
AppleScript
"Hello world!"
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Rust
Rust
  use num_integer::Integer; use std::{f64, usize};   const MAXSIZE: usize = 200;   #[derive(Debug)] struct HerionanTriangle { a: usize, b: usize, c: usize, area: usize, perimeter: usize, }   fn get_area(a: &usize, b: &usize, c: &usize) -> f64 { let s = (a + b + c) as f64 / 2.; (s * (s - *a a...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#Erlang
Erlang
-module(test). -export([first/1, second/0]).   first(F) -> F(). second() -> hello.
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#UNIX_Shell
UNIX Shell
while true; do { echo -e 'HTTP/1.1 200 OK\r\n'; echo 'Hello, World!'; } | nc -l 8080; done
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#Wart
Wart
with server_socket socket :port 4000 accepting client :from socket making stdout outfile+fd.client prn "HTTP/1.0 200 OK" prn "Content-type: text/plain" prn "" prn "Hello, world!"
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#Visual_Basic_.NET
Visual Basic .NET
Module Module1   Function Horner(coefficients As Double(), variable As Double) As Double Return coefficients.Reverse().Aggregate(Function(acc, coeff) acc * variable + coeff) End Function   Sub Main() Console.WriteLine(Horner({-19.0, 7.0, -4.0, 6.0}, 3.0)) End Sub   End Module
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#Visual_FoxPro
Visual FoxPro
  LOCAL x As Double LOCAL ARRAY aCoeffs[1] CLEAR CREATE CURSOR coeffs (c1 I, c2 I, c3 I, c4 I) INSERT INTO coeffs VALUES (-19,7,-4,6) SCATTER TO aCoeffs x = VAL(INPUTBOX("Value of x:", "Value")) ? EvalPoly(@aCoeffs, x) USE IN coeffs   FUNCTION EvalPoly(c, x As Double) As Double LOCAL s As Double, k As Integer, n As Int...
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#Sidef
Sidef
require('Date::Calc')   var abbr = < Nil Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec >   var holidays = [ [Easter => 0], [Ascension => 39], [Pentecost => 49], [Trinity => 56], [Corpus => 60], ]   func easter(year) { var ay = (year % 19) var by = (year // 100) var cy = (year %...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#Peloton
Peloton
  <@ SAYURLLIT>http://rosettacode.org/wiki/Main_Page</@>  
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#Perl
Perl
use strict; use warnings; require 5.014; # check HTTP::Tiny part of core use HTTP::Tiny;   print( HTTP::Tiny->new()->get( 'http://rosettacode.org')->{content} );
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Visual_Basic_.NET
Visual Basic .NET
Module Module1   Sub Main() Console.Error.WriteLine("Goodbye, World!") End Sub   End Module
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#WDTE
WDTE
io.writeln io.stderr 'Goodbye, World!';
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Wren
Wren
Fiber.abort("Goodbye, World!")
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#X86_Assembly
X86 Assembly
section .data msg db 'Goodbye, World!', 0AH len equ $-msg   section .text global _start _start: mov edx, len mov ecx, msg mov ebx, 2 mov eax, 4 int 80h   mov ebx, 1 mov eax, 1 int 80h
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#Picat
Picat
go => println([q(I) : I in 1..10]), println(q1000=q(1000)), Q = {q(I) : I in 1..100_000}, println(flips=sum({1 : I in 2..100_000, Q[I-1] > Q[I]})), nl.   table q(1) = 1. q(2) = 1. q(N) = q(N-q(N-1)) + q(N-q(N-2)).
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#PicoLisp
PicoLisp
(de q (N) (cache '(NIL) N (if (>= 2 N) 1 (+ (q (- N (q (dec N)))) (q (- N (q (- N 2)))) ) ) ) )
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Applesoft_BASIC
Applesoft BASIC
PRINT "Hello world!"
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Scala
Scala
object Heron extends scala.collection.mutable.MutableList[Seq[Int]] with App { private final val n = 200 for (c <- 1 to n; b <- 1 to c; a <- 1 to b if gcd(gcd(a, b), c) == 1) { val p = a + b + c val s = p / 2D val area = Math.sqrt(s * (s - a) * (s - b) * (s - c)) if (isHeron(area...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#ERRE
ERRE
  PROGRAM FUNC_PASS   FUNCTION ONE(X,Y) ONE=(X+Y)^2 END FUNCTION   FUNCTION TWO(X,Y) TWO=ONE(X,Y)+1 END FUNCTION   BEGIN PRINT(TWO(10,11)) END PROGRAM  
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#Wren
Wren
import "web" for Routes, App   Routes.GET("/") { return "Goodbye, World!" }   App.run(8080)
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#X86-64_Assembly
X86-64 Assembly
  ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Crossplatform(?) Web Server example using UASM's OO Language extention ;; ;; Linux Build: ;; $ uasm -elf64 websrv.asm ;; $ gcc -o websrv websrv.o -no-pie ;; With MUSL libc ;; $ musl-gcc -o websrv websrv.o -e main -nostartfiles -no-...
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#Vlang
Vlang
fn horner(x i64, c []i64) i64 { mut acc := i64(0) for i := c.len - 1; i >= 0; i-- { acc = acc*x + c[i] } return acc }   fn main() { println(horner(3, [i64(-19), 7, -4, 6])) }
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#Wren
Wren
var horner = Fn.new { |x, c| var count = c.count if (count == 0) return 0 return (count-1..0).reduce(0) { |acc, index| acc*x + c[index] } }   System.print(horner.call(3, [-19, 7, -4, 6]))
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#Tcl
Tcl
package require Tcl 8.5; # Advanced date handling engine   # Easter computation code from http://www.assa.org.au/edm.html proc EasterDate year { set FirstDig [expr {$year / 100}] set Remain19 [expr {$year % 19}]   # calculate Paschal Full Moon date set temp [expr {($FirstDig - 15)/2 + 202 - 11*$Remain19...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#Phix
Phix
include builtins\libcurl.e curl_global_init() atom curl = curl_easy_init() curl_easy_setopt(curl, CURLOPT_URL, "http://rosettacode.org/robots.txt") object res = curl_easy_perform_ex(curl) curl_easy_cleanup(curl) curl_global_cleanup() puts(1,res)
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#XLISP
XLISP
(DISPLAY "Goodbye, World!" *ERROR-OUTPUT*)
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#XPL0
XPL0
code Text=12; Text(2, "Goodbye, World!")
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Yabasic
Yabasic
  error "Goodbye World!"  
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#Zig
Zig
const std = @import("std"); pub fn main() !void { try std.io.getStdErr().writer().writeAll("Goodbye, World!\n"); // debug messages are also printed to stderr //std.debug.print("Goodbye, World!\n"); }
http://rosettacode.org/wiki/Hello_world/Standard_error
Hello world/Standard error
Hello world/Standard error is part of Short Circuit's Console Program Basics selection. A common practice in computing is to send error messages to a different output stream than normal text console messages. The normal messages print to what is called "standard output" or "standard out". The error messages print to ...
#zkl
zkl
File.stderr.writeln("Goodbye, World!")
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#PL.2FI
PL/I
  /* Hofstrader Q sequence for any "n". */   H: procedure options (main); /* 28 January 2012 */ declare n fixed binary(31);   put ('How many values do you want? :'); get (n);   begin; declare Q(n) fixed binary (31); declare i fixed binary (31);   Q(1), Q(2) = 1; do i = 1 upthru n; if i >= 3 ...
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#PL.2FM
PL/M
100H: BDOS: PROCEDURE (FN, ARG); DECLARE FN BYTE, ARG ADDRESS; GO TO 5; END BDOS; EXIT: PROCEDURE; CALL BDOS(0,0); END EXIT; PRINT: PROCEDURE (S); DECLARE S ADDRESS; CALL BDOS(9,S); END PRINT;   PRINT$NUMBER: PROCEDURE (N); DECLARE S (7) BYTE INITIAL ('..... $'); DECLARE (N, P) ADDRESS, C BASED P BYTE; P = ...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Apricot
Apricot
(puts "Hello world!")
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Sidef
Sidef
class Triangle(a, b, c) {   has (sides, perimeter, area)   method init { sides = [a, b, c].sort perimeter = [a, b, c].sum var s = (perimeter / 2) area = sqrt(s * (s - a) * (s - b) * (s - c)) }   method is_valid(a,b,c) { var (short, middle, long) = [a, b, c].sort...; (short + middle) > lo...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#Euler_Math_Toolbox
Euler Math Toolbox
  >function f(x,a) := x^a-a^x >function dof (f$:string,x) := f$(x,args()); >dof("f",1:5;2) [ -1 0 1 0 -7 ] >plot2d("f",1,5;2):  
http://rosettacode.org/wiki/Hello_world/Web_server
Hello world/Web server
The browser is the new GUI ! Task Serve our standard text   Goodbye, World!   to   http://localhost:8080/   so that it can be viewed with a web browser. The provided solution must start or implement a server that accepts multiple client connections and serves text as requested. Note that starting a web browser or...
#zkl
zkl
const PORT=8080; const SERVLET_THREADS=4;   // A class to process requests from clients (eg browsers) // in a thread. Requests are received via a pipe, which feeds // all Servlet threads. class Servlet{ fcn init(jobPipe){ self.launch(jobPipe); } fcn liftoff(jobPipe){ while(1){ // read request...
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#XPL0
XPL0
code IntOut=11;   func Horner(X, N, C); \Return value of polynomial in X int X, N, C; \variable, number of terms, coefficient list int A, I; [A:= 0; for I:= N-1 downto 0 do A:= A*X + C(I); return A; ];   IntOut(0, Horner(3, 4, [-19, 7, -4, 6]));
http://rosettacode.org/wiki/Horner%27s_rule_for_polynomial_evaluation
Horner's rule for polynomial evaluation
A fast scheme for evaluating a polynomial such as: − 19 + 7 x − 4 x 2 + 6 x 3 {\displaystyle -19+7x-4x^{2}+6x^{3}\,} when x = 3 {\displaystyle x=3\;} . is to arrange the computation as follows: ( ( ( ( 0 ) x + 6 ) x + ( − 4 ) ) x + 7 ) x + ( − 19 ) {\displaystyle ((((0)x+6)x+(-4))x...
#zkl
zkl
fcn horner(coeffs,x) { coeffs.reverse().reduce('wrap(a,coeff){ a*x + coeff },0.0) }
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#TUSCRIPT
TUSCRIPT
  $$ MODE TUSCRIPT SET years=* LOOP period1=400,2100,100 SET years=APPEND(years,period1) ENDLOOP LOOP period2=2010,2020 SET years=APPEND(years,period2) ENDLOOP SET years=DIGIT SORT (years) LOOP year=years SET dayofweek=DATE (EASTER,day,month,year,nreaster) PRINT " Easter: ",year," ",month," ",day LOOP nr="39'49'56'6...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#PHP
PHP
  readfile("http://www.rosettacode.org");  
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#PureBasic
PureBasic
If Not OpenConsole("Hofstadter Q sequence") End 1 EndIf   #N = 100000 Define i.i, flip.i = 0 Dim q.i(#N) q(1) = 1 q(2) = 1 For i = 3 To #N q(i) = q(i - q(i - 1)) + q(i - q(i - 2)) Next For i = 1 To #N - 1 flip + Bool(q(i) > q(i + 1)) Next   Print(~"First ten:\t") For i = 1 To 10 : Print(LSet(Str(q(i)), 3)) : Next...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Arc
Arc
(prn "Hello world!")
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Smalltalk
Smalltalk
perimeter := [:triangle | triangle reduce: #+].   squaredArea := [:triangle | | s | s := (perimeter value: triangle) / 2. triangle inject: s into: [:a2 :edge | s - edge * a2]].   isPrimitive := [:triangle | (triangle reduce: #gcd:) = 1].   isHeronian := [:triangle | (squaredArea value: triangle) sqrt isInteger].  ...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#Euphoria
Euphoria
procedure use(integer fi, integer a, integer b) print(1,call_func(fi,{a,b})) end procedure   function add(integer a, integer b) return a + b end function   use(routine_id("add"),23,45)
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#VBA
VBA
Public dates As Variant Private Function easter(year_ As Integer) As Date '-- from https://en.wikipedia.org/wiki/Computus#Anonymous_Gregorian_algorithm Dim a As Integer, b As Integer, c As Integer, d As Integer, e As Integer Dim f As Integer, g As Integer, h As Integer, i As Integer, k As Integer Dim l As I...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#PicoLisp
PicoLisp
  (load "@lib/http.l")   (client "rosettacode.org" 80 NIL # Connect to rosettacode (out NIL (echo)) ) # Echo to standard output  
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#Pike
Pike
  write("%s",Protocols.HTTP.get_url_data("http://www.rosettacode.org"));  
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#Python
Python
def q(n): if n < 1 or type(n) != int: raise ValueError("n must be an int >= 1") try: return q.seq[n] except IndexError: ans = q(n - q(n - 1)) + q(n - q(n - 2)) q.seq.append(ans) return ans q.seq = [None, 1, 1]   if __name__ == '__main__': first10 = [q(i) for i in range(1,...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Arendelle
Arendelle
"Hello world!"
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#SPL
SPL
h,t = getem(200) #.sort(h,4,5,1,2,3) #.output("There are ",t," Heronian triangles") #.output(" a b c area perimeter") #.output("----- ----- ----- ------ ---------") > i, 1..#.min(10,t) print(h,i) < #.output(#.str("...",">34<")) > i, 1..t  ? h[4,i]=210, print(h,i) < print(h,i)= #.output(#.str(h[1,i],">...
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Swift
Swift
import Foundation   typealias PrimitiveHeronianTriangle = (s1:Int, s2:Int, s3:Int, p:Int, a:Int)   func heronianArea(side1 s1:Int, side2 s2:Int, side3 s3:Int) -> Int? { let d1 = Double(s1) let d2 = Double(s2) let d3 = Double(s3)   let s = (d1 + d2 + d3) / 2.0 let a = sqrt(s * (s - d1) * (s - d2) * (...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#F.23
F#
> let twice f x = f (f x);;   val twice : ('a -> 'a) -> 'a -> 'a   > twice System.Math.Sqrt 81.0;; val it : float = 3.0
http://rosettacode.org/wiki/Holidays_related_to_Easter
Holidays related to Easter
Task Calculate the dates of:   Easter   Ascension Thursday   Pentecost   Trinity Sunday   Corpus Christi feast (for Catholic)   All Saints' Sunday (for Orthodox) As an example, calculate for the first year of each century from;   years     400   to   2100 CE   and for   years   2010   to   2020 CE. Note ...
#Wren
Wren
import "/date" for Date import "/fmt" for Fmt import "/trait" for Stepped   var holidayOffsets = [ ["Easter", 0], ["Ascension", 39], ["Pentecost", 49], ["Trinity", 56], ["C/Christi", 60] ]   var calculateEaster = Fn.new { |year| var a = year % 19 var b = (year / 100).floor var c = year %...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#PowerShell
PowerShell
  $wc = New-Object Net.WebClient $wc.DownloadString('http://www.rosettacode.org')  
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#Quackery
Quackery
[ 2dup swap size dup negate swap within not if [ drop size 1+ number$ $ "Term " swap join $ " of the Q sequence is not defined." join message put bail ] peek ] is qpeek ( [ n --> x )   [ dup dup -1 qpeek negate qpeek dip [ dup dup -2 qpeek n...
http://rosettacode.org/wiki/Hofstadter_Q_sequence
Hofstadter Q sequence
Hofstadter Q sequence Q ( 1 ) = Q ( 2 ) = 1 , Q ( n ) = Q ( n − Q ( n − 1 ) ) + Q ( n − Q ( n − 2 ) ) , n > 2. {\displaystyle {\begin{aligned}Q(1)&=Q(2)=1,\\Q(n)&=Q{\big (}n-Q(n-1){\big )}+Q{\big (}n-Q(n-2){\big )},\quad n>2.\end{aligned}}} It is defined like the Fibonacc...
#R
R
  cache <- vector("integer", 0) cache[1] <- 1 cache[2] <- 1   Q <- function(n) { if (is.na(cache[n])) { value <- Q(n-Q(n-1)) + Q(n-Q(n-2)) cache[n] <<- value } cache[n] }   for (i in 1:1e5) { Q(i) }   for (i in 1:10) { cat(Q(i)," ",sep = "") } cat("\n") cat(Q(1000),"\n")   count <- 0 for (i in 2:1e5) ...
http://rosettacode.org/wiki/Hello_world/Text
Hello world/Text
Hello world/Text is part of Short Circuit's Console Program Basics selection. Task Display the string Hello world! on a text console. Related tasks   Hello world/Graphical   Hello world/Line Printer   Hello world/Newbie   Hello world/Newline omission   Hello world/Standard error   Hello world/Web server
#Argile
Argile
use std print "Hello world!"
http://rosettacode.org/wiki/Heronian_triangles
Heronian triangles
Hero's formula for the area of a triangle given the length of its three sides   a,   b,   and   c   is given by: A = s ( s − a ) ( s − b ) ( s − c ) , {\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}},} where   s   is half the perimeter of the triangle; that is, s = a + b + c 2 . {\displaystyle s...
#Tcl
Tcl
  if {[info commands let] eq ""} {   #make some math look nicer: proc let {name args} { tailcall ::set $name [uplevel 1 $args] } interp alias {} = {} expr namespace import ::tcl::mathfunc::* ::tcl::mathop::* interp alias {} sum {} +   # a simple adaptation of gcd from http://wiki.tcl...
http://rosettacode.org/wiki/Higher-order_functions
Higher-order functions
Task Pass a function     as an argument     to another function. Related task   First-class functions
#Factor
Factor
USING: io ; IN: rosetacode : argument-function1 ( -- ) "Hello World!" print ; : argument-function2 ( -- ) "Goodbye World!" print ;   ! normal words have to know the stack effect of the input parameters they execute : calling-function1 ( another-function -- ) execute( -- ) ;   ! unlike normal words, inline words do not ...
http://rosettacode.org/wiki/HTTP
HTTP
Task Access and print a URL's content (the located resource) to the console. There is a separate task for HTTPS Requests.
#Prolog
Prolog
  :- use_module(library( http/http_open )).   http :- http_open('http://www.rosettacode.org/',In, []), copy_stream_data(In, user_output), close(In).