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http://rosettacode.org/wiki/Truncatable_primes
Truncatable primes
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 739, 73, and 7 formed by removing digits from its right are also prime. No zeroes are allowed in truncatable primes. Task The task is to find the largest left-truncatable and right-truncatable primes less than one million (base 10 is implied). Related tasks Find largest left truncatable prime in a given base Sieve of Eratosthenes See also Truncatable Prime from MathWorld.]
#PicoLisp
PicoLisp
(load "@lib/rsa.l") # Use the 'prime?' function from RSA package   (de truncatablePrime? (N Fun) (for (L (chop N) L (Fun L)) (T (= "0" (car L))) (NIL (prime? (format L))) T ) )   (let (Left 1000000 Right 1000000) (until (truncatablePrime? (dec 'Left) cdr)) (until (truncatablePrime? (dec 'Right) '((L) (cdr (rot L))))) (cons Left Right) )
http://rosettacode.org/wiki/Truncatable_primes
Truncatable primes
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 739, 73, and 7 formed by removing digits from its right are also prime. No zeroes are allowed in truncatable primes. Task The task is to find the largest left-truncatable and right-truncatable primes less than one million (base 10 is implied). Related tasks Find largest left truncatable prime in a given base Sieve of Eratosthenes See also Truncatable Prime from MathWorld.]
#Pike
Pike
bool is_trunc_prime(int p, string direction) { while(p) { if( !p->probably_prime_p() ) return false; if(direction == "l") p = (int)p->digits()[1..]; else p = (int)p->digits()[..<1]; } return true; }   void main() { bool ltp_found, rtp_found; for(int prime = 10->pow(6); prime--; prime > 0) { if( !ltp_found && is_trunc_prime(prime, "l") ) { ltp_found = true; write("Largest LTP: %d\n", prime); } if( !rtp_found && is_trunc_prime(prime, "r") ) { rtp_found = true; write("Largest RTP: %d\n", prime); } if(ltp_found && rtp_found) break; } }
http://rosettacode.org/wiki/Tree_traversal
Tree traversal
Task Implement a binary tree where each node carries an integer,   and implement:   pre-order,   in-order,   post-order,     and   level-order   traversal. Use those traversals to output the following tree: 1 / \ / \ / \ 2 3 / \ / 4 5 6 / / \ 7 8 9 The correct output should look like this: preorder: 1 2 4 7 5 3 6 8 9 inorder: 7 4 2 5 1 8 6 9 3 postorder: 7 4 5 2 8 9 6 3 1 level-order: 1 2 3 4 5 6 7 8 9 See also   Wikipedia article:   Tree traversal.
#D
D
import std.stdio, std.traits;   const final class Node(T) { T data; Node left, right;   this(in T data, in Node left=null, in Node right=null) const pure nothrow { this.data = data; this.left = left; this.right = right; } }   // 'static' templated opCall can't be used in Node auto node(T)(in T data, in Node!T left=null, in Node!T right=null) pure nothrow { return new const(Node!T)(data, left, right); }   void show(T)(in T x) { write(x, " "); }   enum Visit { pre, inv, post }   // 'visitor' can be any kind of callable or it uses a default visitor. // TNode can be any kind of Node, with data, left and right fields, // so this is more generic than a member function of Node. void backtrackingOrder(Visit v, TNode, TyF=void*) (in TNode node, TyF visitor=null) { alias trueVisitor = Select!(is(TyF == void*), show, visitor); if (node !is null) { static if (v == Visit.pre) trueVisitor(node.data); backtrackingOrder!v(node.left, visitor); static if (v == Visit.inv) trueVisitor(node.data); backtrackingOrder!v(node.right, visitor); static if (v == Visit.post) trueVisitor(node.data); } }   void levelOrder(TNode, TyF=void*) (in TNode node, TyF visitor=null, const(TNode)[] more=[]) { alias trueVisitor = Select!(is(TyF == void*), show, visitor); if (node !is null) { more ~= [node.left, node.right]; trueVisitor(node.data); } if (more.length) levelOrder(more[0], visitor, more[1 .. $]); }   void main() { alias N = node; const tree = N(1, N(2, N(4, N(7)), N(5)), N(3, N(6, N(8), N(9))));   write(" preOrder: "); tree.backtrackingOrder!(Visit.pre); write("\n inorder: "); tree.backtrackingOrder!(Visit.inv); write("\n postOrder: "); tree.backtrackingOrder!(Visit.post); write("\nlevelorder: "); tree.levelOrder; writeln; }
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#C.23
C#
string str = "Hello,How,Are,You,Today"; // or Regex.Split ( "Hello,How,Are,You,Today", "," ); // (Regex is in System.Text.RegularExpressions namespace) string[] strings = str.Split(','); Console.WriteLine(String.Join(".", strings));  
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#C.2B.2B
C++
#include <string> #include <sstream> #include <vector> #include <iterator> #include <iostream> #include <algorithm> int main() { std::string s = "Hello,How,Are,You,Today"; std::vector<std::string> v; std::istringstream buf(s); for(std::string token; getline(buf, token, ','); ) v.push_back(token); copy(v.begin(), v.end(), std::ostream_iterator<std::string>(std::cout, ".")); std::cout << '\n'; }
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#BBC_BASIC
BBC BASIC
start%=TIME:REM centi-second timer REM perform processing lapsed%=TIME-start%
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Bracmat
Bracmat
( ( time = fun funarg t0 ret .  !arg:(?fun.?funarg) & clk$:?t0 & !fun$!funarg:?ret & (!ret.flt$(clk$+-1*!t0,3) s) ) & ( fib = .  !arg:<2&1 | fib$(!arg+-1)+fib$(!arg+-2) ) & time$(fib.30) )
http://rosettacode.org/wiki/Top_rank_per_group
Top rank per group
Task Find the top   N   salaries in each department,   where   N   is provided as a parameter. Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source: Employee Name,Employee ID,Salary,Department Tyler Bennett,E10297,32000,D101 John Rappl,E21437,47000,D050 George Woltman,E00127,53500,D101 Adam Smith,E63535,18000,D202 Claire Buckman,E39876,27800,D202 David McClellan,E04242,41500,D101 Rich Holcomb,E01234,49500,D202 Nathan Adams,E41298,21900,D050 Richard Potter,E43128,15900,D101 David Motsinger,E27002,19250,D202 Tim Sampair,E03033,27000,D101 Kim Arlich,E10001,57000,D190 Timothy Grove,E16398,29900,D190
#Dyalect
Dyalect
type Employee(name,id,salary,department) with Lookup   func Employee.ToString() { "$\(this.salary) (name: \(this.name), id: \(this.id), department: \(this.department)" }   let employees = [ Employee("Tyler Bennett","E10297",32000,"D101"), Employee("John Rappl","E21437",47000,"D050"), Employee("George Woltman","E00127",53500,"D101"), Employee("Adam Smith","E63535",18000,"D202"), Employee("Claire Buckman","E39876",27800,"D202"), Employee("David McClellan","E04242",41500,"D101"), Employee("Rich Holcomb","E01234",49500,"D202"), Employee("Nathan Adams","E41298",21900,"D050"), Employee("Richard Potter","E43128",15900,"D101"), Employee("David Motsinger","E27002",19250,"D202"), Employee("Tim Sampair","E03033",27000,"D101"), Employee("Kim Arlich","E10001",57000,"D190"), Employee("Timothy Grove","E16398",29900,"D190") ]   func topNSalaries(n) { //We sort employees based on salary employees.Sort((x,y) => y.salary - x.salary) let max = if n > employees.Length() - 1 { employees.Length() - 1 } else { n } for i in 0..max { yield employees[i] } }   var seq = topNSalaries(5)   for e in seq { print(e) }
http://rosettacode.org/wiki/Tic-tac-toe
Tic-tac-toe
Task Play a game of tic-tac-toe. Ensure that legal moves are played and that a winning position is notified. Tic-tac-toe   is also known as:   naughts and crosses   tic tac toe   tick tack toe   three in a row   tres en rayo       and   Xs  and  Os See also   MathWorld™, Tic-Tac-Toe game.   Wikipedia tic-tac-toe.
#BASIC
BASIC
  # basado en código de Antonio Rodrigo dos Santos Silva (gracias): # http://statusgear.freeforums.net/thread/17/basic-256-tic-tac-toe   global playerturn$ global endGame$ global space$ global player1Score$ global player2Score$ global invalidMove$ global tecla$ global keyQ$ global keyW$ global keyE$ global keyA$ global keyS$ global keyD$ global keyZ$ global keyX$ global keyC$ global keySpace$ global keyEsc$   keyQ$ = 81 keyW$ = 87 keyE$ = 69 keyA$ = 65 keyS$ = 83 keyD$ = 68 keyZ$ = 90 keyX$ = 88 keyC$ = 67 keySpace$ = 32 keyEsc$ = 16777216   dim space$(9)     subroutine clearGameVars() playerturn$ = 1 invalidMove$ = 0 endGame$ = 0 tecla$ = 0   for t = 0 to space$[?]-1 space$[t] = 0 next t end subroutine   subroutine endGame() cls print "¡Hasta pronto!..." end end subroutine   subroutine printBoard() print " " + space$[0]+" | "+space$[1]+" | "+space$[2] print " " + "— + — + —" print " " + space$[3]+" | "+space$[4]+" | "+space$[5] print " " + "— + — + —" print " " + space$[6]+" | "+space$[7]+" | "+space$[8] print "" end subroutine   subroutine changePlayer() if playerturn$ = 1 then playerturn$ = 2 else playerturn$ = 1 end if end subroutine   subroutine endMatchWithWinner() cls call printPlayerScore() call printBoard() endGame$ = 1   if playerturn$ = 1 then player1Score$ += 1 else player2Score$ += 1 end if   print "¡Jugador " + playerturn$ + " gana!" + chr(10) print "Pulsa [SPACE] para jugar otra partida" print "Pulsa [ESC] para dejar de jugar" do tecla$ = key pause .01 if tecla$ = keySpace$ then call gamePlay() if tecla$ = keyEsc$ then call endGame() until false end subroutine   subroutine endMatchWithoutWinner() cls call printPlayerScore() call printBoard() endGame$ = 1   print " Nadie ganó :( " + chr(10) print " Pulsa [SPACE] para comenzar o [ESC] para salir. " do tecla$ = key pause .01 if tecla$ = keySpace$ then call gamePlay() if tecla$ = keyEsc$ then call endGame() until false end subroutine   subroutine printPlayerScore() print "--------------------------------------------" print " Jugador #1: " + player1Score$ + " pts" print " Jugador #2: " + player2Score$ + " pts" print "--------------------------------------------" + chr(10) end subroutine     subroutine printPlayerMessage() print "Jugador: " + playerturn$ + ", elige una casilla, por favor." end subroutine   subroutine gamePlay() call clearGameVars() cls call printPlayerScore() call printBoard() call printPlayerMessage() while 0 = 0 invalidMove$ = 0   if endGame$ = 0 then do tecla$ = key pause .01 validKeypressed$ = 0 if tecla$ = keyQ$ or tecla$ = keyW$ or tecla$ = keyE$ or tecla$ = keyA$ or tecla$ = keyS$ or tecla$ = keyD$ or tecla$ = keyZ$ or tecla$ = keyX$ or tecla$ = keyC$ then validKeypressed$ = 1 until validKeypressed$ = 1 endif   if tecla$ = keyQ$ then if space$[0] = 0 then space$[0] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyW$ then if space$[1] = 0 then space$[1] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyE$ then if space$[2] = 0 then space$[2] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyA$ then if space$[3] = 0 then space$[3] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyS$ then if space$[4] = 0 then space$[4] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyD$ then if space$[5] = 0 then space$[5] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyZ$ then if space$[6] = 0 then space$[6] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyX$ then if space$[7] = 0 then space$[7] = playerturn$ else invalidMove$ = 1 endif endif   if tecla$ = keyC$ then if space$[8] = 0 then space$[8] = playerturn$ else invalidMove$ = 1 endif endif   if invalidMove$ = 0 then tecla$ = 0   if space$[0] = 1 and space$[1] = 1 and space$[2] = 1 then call endMatchWithWinner() if space$[3] = 1 and space$[4] = 1 and space$[5] = 1 then call endMatchWithWinner() if space$[6] = 1 and space$[7] = 1 and space$[8] = 1 then call endMatchWithWinner() if space$[0] = 1 and space$[3] = 1 and space$[6] = 1 then call endMatchWithWinner() if space$[1] = 1 and space$[4] = 1 and space$[7] = 1 then call endMatchWithWinner() if space$[2] = 1 and space$[5] = 1 and space$[8] = 1 then call endMatchWithWinner() if space$[0] = 1 and space$[4] = 1 and space$[8] = 1 then call endMatchWithWinner() if space$[2] = 1 and space$[4] = 1 and space$[6] = 1 then call endMatchWithWinner() if space$[0] = 2 and space$[1] = 2 and space$[2] = 2 then call endMatchWithWinner() if space$[3] = 2 and space$[4] = 2 and space$[5] = 2 then call endMatchWithWinner() if space$[6] = 2 and space$[7] = 2 and space$[8] = 2 then call endMatchWithWinner() if space$[0] = 2 and space$[3] = 2 and space$[6] = 2 then call endMatchWithWinner() if space$[1] = 2 and space$[4] = 2 and space$[7] = 2 then call endMatchWithWinner() if space$[2] = 2 and space$[5] = 2 and space$[8] = 2 then call endMatchWithWinner() if space$[0] = 2 and space$[4] = 2 and space$[8] = 2 then call endMatchWithWinner() if space$[2] = 2 and space$[4] = 2 and space$[6] = 2 then call endMatchWithWinner()   if space$[0] <> 0 and space$[1] <> 0 and space$[2] <> 0 and space$[3] <> 0 and space$[4] <> 0 and space$[5] <> 0 and space$[6] <> 0 and space$[7] <> 0 and space$[8] <> 0 then call endMatchWithoutWinner()   call changePlayer() cls call printPlayerScore() call printBoard() call printPlayerMessage() end if   end while end subroutine   subroutine gameMenu() cls call clearGameVars()   player1Score$ = 0 player2Score$ = 0   print "=================================================" print "| TIC-TAC-TOE |" print "=================================================" + chr(10) print " Teclas para jugar:" print "---------------------" print " | q | w | e |" print " | a | s | d |" print " | z | x | c |" + chr(10) print " Pulsa [SPACE] para comenzar o [ESC] para salir. "   do tecla$ = key pause .01 if tecla$ = keySpace$ then call gamePlay() if tecla$ = keyEsc$ then call endGame() until false end subroutine   call gameMenu() end  
http://rosettacode.org/wiki/Towers_of_Hanoi
Towers of Hanoi
Task Solve the   Towers of Hanoi   problem with recursion.
#Batch_File
Batch File
@echo off setlocal enabledelayedexpansion   %==The main thing==% %==First param - Number of disks==% %==Second param - Start pole==% %==Third param - End pole==% %==Fourth param - Helper pole==% call :move 4 START END HELPER echo. pause exit /b 0   %==The "function"==% :move setlocal set n=%1 set from=%2 set to=%3 set via=%4   if %n% gtr 0 ( set /a x=!n!-1 call :move !x! %from% %via% %to% echo Move top disk from pole %from% to pole %to%. call :move !x! %via% %to% %from% ) exit /b 0
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#J
J
(, -.)@]^:[&0]9 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 0 0 1 1 0 1 0 0 1 ...
http://rosettacode.org/wiki/Tonelli-Shanks_algorithm
Tonelli-Shanks algorithm
This page uses content from Wikipedia. The original article was at Tonelli-Shanks algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In computational number theory, the Tonelli–Shanks algorithm is a technique for solving for x in a congruence of the form: x2 ≡ n (mod p) where n is an integer which is a quadratic residue (mod p), p is an odd prime, and x,n ∈ Fp where Fp = {0, 1, ..., p - 1}. It is used in cryptography techniques. To apply the algorithm, we need the Legendre symbol: The Legendre symbol (a | p) denotes the value of a(p-1)/2 (mod p). (a | p) ≡ 1    if a is a square (mod p) (a | p) ≡ -1    if a is not a square (mod p) (a | p) ≡ 0    if a ≡ 0 (mod p) Algorithm pseudo-code All ≡ are taken to mean (mod p) unless stated otherwise. Input: p an odd prime, and an integer n . Step 0: Check that n is indeed a square: (n | p) must be ≡ 1 . Step 1: By factoring out powers of 2 from p - 1, find q and s such that p - 1 = q2s with q odd . If p ≡ 3 (mod 4) (i.e. s = 1), output the two solutions r ≡ ± n(p+1)/4 . Step 2: Select a non-square z such that (z | p) ≡ -1 and set c ≡ zq . Step 3: Set r ≡ n(q+1)/2, t ≡ nq, m = s . Step 4: Loop the following: If t ≡ 1, output r and p - r . Otherwise find, by repeated squaring, the lowest i, 0 < i < m , such that t2i ≡ 1 . Let b ≡ c2(m - i - 1), and set r ≡ rb, t ≡ tb2, c ≡ b2 and m = i . Task Implement the above algorithm. Find solutions (if any) for n = 10 p = 13 n = 56 p = 101 n = 1030 p = 10009 n = 1032 p = 10009 n = 44402 p = 100049 Extra credit n = 665820697 p = 1000000009 n = 881398088036 p = 1000000000039 n = 41660815127637347468140745042827704103445750172002 p = 10^50 + 577 See also Modular exponentiation Cipolla's algorithm
#REXX
REXX
/* REXX (required by some interpreters) */ Numeric Digits 1000000 ttest ='[(10, 13), (56, 101), (1030, 10009), (44402, 100049)]' Do While pos('(',ttest)>0 Parse Var ttest '(' n ',' p ')' ttest r = tonelli(n, p) Say "n =" n "p =" p Say " roots :" r (p - r) End Exit   legendre: Procedure Parse Arg a, p return pow(a, (p - 1) % 2, p)   tonelli: Procedure Parse Arg n, p q = p - 1 s = 0 Do while q // 2 == 0 q = q % 2 s = s+1 End if s == 1 Then return pow(n, (p + 1) % 4, p) Do z=2 To p if p - 1 == legendre(z, p) Then Leave End c = pow(z, q, p) r = pow(n, (q + 1) / 2, p) t = pow(n, q, p) m = s t2 = 0 Do while (t - 1) // p <> 0 t2 = (t * t) // p Do i=1 To m if (t2 - 1) // p == 0 Then Leave t2 = (t2 * t2) // p End y=2**(m - i - 1) b = pow(c, y, p) If b=10008 Then Trace ?R r = (r * b) // p c = (b * b) // p t = (t * c) // p m = i End return r pow: Procedure Parse Arg x,y,z If y>0 Then p=x**y Else p=x If z>'' Then p=p//z Return p
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#JavaScript
JavaScript
function tokenize(s, esc, sep) { for (var a=[], t='', i=0, e=s.length; i<e; i+=1) { var c = s.charAt(i) if (c == esc) t+=s.charAt(++i) else if (c != sep) t+=c else a.push(t), t='' } a.push(t) return a }   var s = 'one^|uno||three^^^^|four^^^|^cuatro|' document.write(s, '<br>') for (var a=tokenize(s,'^','|'), i=0; i<a.length; i+=1) document.write(i, ': ', a[i], '<br>')
http://rosettacode.org/wiki/Total_circles_area
Total circles area
Total circles area You are encouraged to solve this task according to the task description, using any language you may know. Example circles Example circles filtered Given some partially overlapping circles on the plane, compute and show the total area covered by them, with four or six (or a little more) decimal digits of precision. The area covered by two or more disks needs to be counted only once. One point of this Task is also to compare and discuss the relative merits of various solution strategies, their performance, precision and simplicity. This means keeping both slower and faster solutions for a language (like C) is welcome. To allow a better comparison of the different implementations, solve the problem with this standard dataset, each line contains the x and y coordinates of the centers of the disks and their radii   (11 disks are fully contained inside other disks): xc yc radius 1.6417233788 1.6121789534 0.0848270516 -1.4944608174 1.2077959613 1.1039549836 0.6110294452 -0.6907087527 0.9089162485 0.3844862411 0.2923344616 0.2375743054 -0.2495892950 -0.3832854473 1.0845181219 1.7813504266 1.6178237031 0.8162655711 -0.1985249206 -0.8343333301 0.0538864941 -1.7011985145 -0.1263820964 0.4776976918 -0.4319462812 1.4104420482 0.7886291537 0.2178372997 -0.9499557344 0.0357871187 -0.6294854565 -1.3078893852 0.7653357688 1.7952608455 0.6281269104 0.2727652452 1.4168575317 1.0683357171 1.1016025378 1.4637371396 0.9463877418 1.1846214562 -0.5263668798 1.7315156631 1.4428514068 -1.2197352481 0.9144146579 1.0727263474 -0.1389358881 0.1092805780 0.7350208828 1.5293954595 0.0030278255 1.2472867347 -0.5258728625 1.3782633069 1.3495508831 -0.1403562064 0.2437382535 1.3804956588 0.8055826339 -0.0482092025 0.3327165165 -0.6311979224 0.7184578971 0.2491045282 1.4685857879 -0.8347049536 1.3670667538 -0.6855727502 1.6465021616 1.0593087096 0.0152957411 0.0638919221 0.9771215985 The result is   21.56503660... . Related task   Circles of given radius through two points. See also http://www.reddit.com/r/dailyprogrammer/comments/zff9o/9062012_challenge_96_difficult_water_droplets/ http://stackoverflow.com/a/1667789/10562
#Wren
Wren
import "/dynamic" for Tuple import "/math" for Nums   var Circle = Tuple.create("Circle", ["x", "y", "r"])   var circles = [ Circle.new( 1.6417233788, 1.6121789534, 0.0848270516), Circle.new(-1.4944608174, 1.2077959613, 1.1039549836), Circle.new( 0.6110294452, -0.6907087527, 0.9089162485), Circle.new( 0.3844862411, 0.2923344616, 0.2375743054), Circle.new(-0.2495892950, -0.3832854473, 1.0845181219), Circle.new( 1.7813504266, 1.6178237031, 0.8162655711), Circle.new(-0.1985249206, -0.8343333301, 0.0538864941), Circle.new(-1.7011985145, -0.1263820964, 0.4776976918), Circle.new(-0.4319462812, 1.4104420482, 0.7886291537), Circle.new( 0.2178372997, -0.9499557344, 0.0357871187), Circle.new(-0.6294854565, -1.3078893852, 0.7653357688), Circle.new( 1.7952608455, 0.6281269104, 0.2727652452), Circle.new( 1.4168575317, 1.0683357171, 1.1016025378), Circle.new( 1.4637371396, 0.9463877418, 1.1846214562), Circle.new(-0.5263668798, 1.7315156631, 1.4428514068), Circle.new(-1.2197352481, 0.9144146579, 1.0727263474), Circle.new(-0.1389358881, 0.1092805780, 0.7350208828), Circle.new( 1.5293954595, 0.0030278255, 1.2472867347), Circle.new(-0.5258728625, 1.3782633069, 1.3495508831), Circle.new(-0.1403562064, 0.2437382535, 1.3804956588), Circle.new( 0.8055826339, -0.0482092025, 0.3327165165), Circle.new(-0.6311979224, 0.7184578971, 0.2491045282), Circle.new( 1.4685857879, -0.8347049536, 1.3670667538), Circle.new(-0.6855727502, 1.6465021616, 1.0593087096), Circle.new( 0.0152957411, 0.0638919221, 0.9771215985) ]   var sq = Fn.new { |v| v * v }   var xMin = Nums.min(circles.map { |c| c.x - c.r }) var xMax = Nums.max(circles.map { |c| c.x + c.r }) var yMin = Nums.min(circles.map { |c| c.y - c.r }) var yMax = Nums.max(circles.map { |c| c.y + c.r }) var boxSide = 3000 var dx = (xMax - xMin) / boxSide var dy = (yMax - yMin) / boxSide var count = 0 for (r in 0...boxSide) { var y = yMin + r * dy for (c in 0...boxSide) { var x = xMin + c * dx var b = circles.any { |c| sq.call(x-c.x) + sq.call(y-c.y) <= sq.call(c.r) } if (b) count = count + 1 } } System.print("Approximate area = %(count * dx * dy)")
http://rosettacode.org/wiki/Topological_sort
Topological sort
Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort O(n2) sorts Bubble sort | Cocktail sort | Cocktail sort with shifting bounds | Comb sort | Cycle sort | Gnome sort | Insertion sort | Selection sort | Strand sort other sorts Bead sort | Bogo sort | Common sorted list | Composite structures sort | Custom comparator sort | Counting sort | Disjoint sublist sort | External sort | Jort sort | Lexicographical sort | Natural sorting | Order by pair comparisons | Order disjoint list items | Order two numerical lists | Object identifier (OID) sort | Pancake sort | Quickselect | Permutation sort | Radix sort | Ranking methods | Remove duplicate elements | Sleep sort | Stooge sort | [Sort letters of a string] | Three variable sort | Topological sort | Tree sort Given a mapping between items, and items they depend on, a topological sort orders items so that no item precedes an item it depends upon. The compiling of a library in the VHDL language has the constraint that a library must be compiled after any library it depends on. A tool exists that extracts library dependencies. Task Write a function that will return a valid compile order of VHDL libraries from their dependencies. Assume library names are single words. Items mentioned as only dependents, (sic), have no dependents of their own, but their order of compiling must be given. Any self dependencies should be ignored. Any un-orderable dependencies should be flagged. Use the following data as an example: LIBRARY LIBRARY DEPENDENCIES ======= ==================== des_system_lib std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee dw01 ieee dw01 dware gtech dw02 ieee dw02 dware dw03 std synopsys dware dw03 dw02 dw01 ieee gtech dw04 dw04 ieee dw01 dware gtech dw05 dw05 ieee dware dw06 dw06 ieee dware dw07 ieee dware dware ieee dware gtech ieee gtech ramlib std ieee std_cell_lib ieee std_cell_lib synopsys Note: the above data would be un-orderable if, for example, dw04 is added to the list of dependencies of dw01. C.f.   Topological sort/Extracted top item. There are two popular algorithms for topological sorting:   Kahn's 1962 topological sort [1]   depth-first search [2] [3]
#Haskell
Haskell
import Data.List ((\\), elemIndex, intersect, nub) import Data.Bifunctor (bimap, first)   combs 0 _ = [[]] combs _ [] = [] combs k (x:xs) = ((x :) <$> combs (k - 1) xs) ++ combs k xs   depLibs :: [(String, String)] depLibs = [ ( "des_system_lib" , "std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee") , ("dw01", "ieee dw01 dware gtech") , ("dw02", "ieee dw02 dware") , ("dw03", "std synopsys dware dw03 dw02 dw01 ieee gtech") , ("dw04", "dw04 ieee dw01 dware gtech") , ("dw05", "dw05 ieee dware") , ("dw06", "dw06 ieee dware") , ("dw07", "ieee dware") , ("dware", "ieee dware") , ("gtech", "ieee gtech") , ("ramlib", "std ieee") , ("std_cell_lib", "ieee std_cell_lib") , ("synopsys", []) ]   toposort :: [(String, String)] -> [String] toposort xs | (not . null) cycleDetect = error $ "Dependency cycle detected for libs " ++ show cycleDetect | otherwise = foldl makePrecede [] dB where dB = (\(x, y) -> (x, y \\ x)) . bimap return words <$> xs makePrecede ts ([x], xs) = nub $ case elemIndex x ts of Just i -> uncurry (++) $ first (++ xs) $ splitAt i ts _ -> ts ++ xs ++ [x] cycleDetect = filter ((> 1) . length) $ (\[(a, as), (b, bs)] -> (a `intersect` bs) ++ (b `intersect` as)) <$> combs 2 dB   main :: IO () main = print $ toposort depLibs
http://rosettacode.org/wiki/Universal_Turing_machine
Universal Turing machine
One of the foundational mathematical constructs behind computer science is the universal Turing Machine. (Alan Turing introduced the idea of such a machine in 1936–1937.) Indeed one way to definitively prove that a language is turing-complete is to implement a universal Turing machine in it. Task Simulate such a machine capable of taking the definition of any other Turing machine and executing it. Of course, you will not have an infinite tape, but you should emulate this as much as is possible. The three permissible actions on the tape are "left", "right" and "stay". To test your universal Turing machine (and prove your programming language is Turing complete!), you should execute the following two Turing machines based on the following definitions. Simple incrementer States: q0, qf Initial state: q0 Terminating states: qf Permissible symbols: B, 1 Blank symbol: B Rules: (q0, 1, 1, right, q0) (q0, B, 1, stay, qf) The input for this machine should be a tape of 1 1 1 Three-state busy beaver States: a, b, c, halt Initial state: a Terminating states: halt Permissible symbols: 0, 1 Blank symbol: 0 Rules: (a, 0, 1, right, b) (a, 1, 1, left, c) (b, 0, 1, left, a) (b, 1, 1, right, b) (c, 0, 1, left, b) (c, 1, 1, stay, halt) The input for this machine should be an empty tape. Bonus: 5-state, 2-symbol probable Busy Beaver machine from Wikipedia States: A, B, C, D, E, H Initial state: A Terminating states: H Permissible symbols: 0, 1 Blank symbol: 0 Rules: (A, 0, 1, right, B) (A, 1, 1, left, C) (B, 0, 1, right, C) (B, 1, 1, right, B) (C, 0, 1, right, D) (C, 1, 0, left, E) (D, 0, 1, left, A) (D, 1, 1, left, D) (E, 0, 1, stay, H) (E, 1, 0, left, A) The input for this machine should be an empty tape. This machine runs for more than 47 millions steps.
#NetLogo
NetLogo
  ;; "A Turing Turtle": a Turing Machine implemented in NetLogo ;; by Dan Dewey 1/16/2016 ;; ;; This NetLogo code implements a Turing Machine, see, e.g., ;; http://en.wikipedia.org/wiki/Turing_machine ;; The Turing machine fits nicely into the NetLogo paradigm in which ;; there are agents (aka the turtles), that move around ;; in a world of "patches" (2D cells). ;; Here, a single agent represents the Turing machine read/write head ;; and the patches represent the Turing tape values via their colors. ;; The 2D array of patches is treated as a single long 1D tape in an ;; obvious way.   ;; This program is presented as a NetLogo example on the page: ;; http://rosettacode.org/wiki/Universal_Turing_machine ;; This file may be larger than others on that page, note however ;; that I include many comments in the code and I have made no ;; effort to 'condense' the code, prefering clarity over compactness. ;; A demo and discussion of this program is on the web page: ;; http://sites.google.com/site/dan3deweyscspaimsportfolio/extra-turing-machine ;; The Copy example machine was taken from: ;; http://en.wikipedia.org/wiki/Turing_machine_examples ;; The "Busy Beaver" machines encoded below were taken from: ;; http://www.logique.jussieu.fr/~michel/ha.html   ;; The implementation here allows 3 symbols (blank, 0, 1) on the tape ;; and 3 head motions (left, stay, right).   ;; The 2D world is nominally set to be 29x29, going from (-14,-14) to ;; (14,14) from lower left to upper right and with (0,0) at the center. ;; This gives a total Turing tape length of 29^2 = 841 cells, sufficient for the ;; "Lazy" Beaver 5,2 example. ;; Since the max-pxcor variable is used in the code below (as opposed to ;; a hard-coded number), the effective tape size can be changed by ;; changing the size of the 2D world with the Settings... button on the interface.   ;; The "Info" tab of the NetLogo interface contains some further comments. ;; - - - - - - -     ;; - - - - - - - - - - - Global/Agent variables ;; These three 2D arrays (lists of lists) encode the Turing Machine rules: ;; WhatToWrite: -1 (Blank), 0, 1 ;; HowToMove: -1 (left), 0(stay), 1 (right) ;; NextState: 0 to N-1, negative value goes to a halt state. ;; The above are a function of the current state and the current tape (patch) value. ;; MachineState is used by the turtle to pass the current state of the Turing machine ;; (or the halt code) to the observer. globals [ WhatToWrite HowToMove NextState MachineState  ;; some other golobals of secondary importance...  ;; set different patch colors to record the Turing tape values BlankColor ZeroColor OneColor  ;; a delay constant to slow down the operation RealTimePerTick ]   ;; We'll have one turtle which is the Turing machine read/write head ;; it will keep track of the current Turing state in its own MyState value turtles-own [ MyState ]     ;; - - - - - - - - - - - to Setup  ;; sets up the world clear-all  ;; clears the world first    ;; Try to not have (too many) ad hoc numbers in the code,  ;; collect and set various values here especially if they might be used in multiple places:  ;; The colors for Blank, Zero and One : (user can can change as desired) set BlankColor 2 ;; dark gray set OneColor green set ZeroColor red  ;; slow it down for the humans to watch set RealTimePerTick 0.2  ;; have simulation go at nice realtime speed   create-turtles 1  ;; create the one Turing turtle [  ;; set default parameters set size 2  ;; set a nominal size set color yellow ;; color of border  ;; set the starting location, some Turing programs will adjust this if needed: setxy 0 0 ;; -1 * max-pxcor -1 * max-pxcor set shape "square2empty"  ;; edited version of "square 2" to have clear in middle    ;; set the starting state - always 0 set MyState 0 set MachineState 0  ;; the turtle will update this global value from now on ]    ;; Define the Turing machine rules with 2D lists.  ;; Based on the selection made on interface panel, setting the string Turing_Program_Selection.  ;; This routine has all the Turing 'programs' in it - it's at the very bottom of this file. LoadTuringProgram    ;; the environment, e.g. the Turing tape ask patches [  ;; all patches are set to the blank color set pcolor BlankColor ]    ;; keep track of time; each tick is a Turing step reset-ticks end     ;; - - - - - - - - - - - - - - - - to Go  ;; this repeatedly does steps    ;; The turtle does the main work ask turtles [ DoOneStep wait RealTimePerTick ]   tick    ;; The Turing turtle will die if it tries to go beyond the cells,  ;; in that case (no turtles left) we'll stop.  ;; Also stop if the MachineState has been set to a negative number (a halt state). if ((count turtles = 0) or (MachineState < 0)) [ stop ]   end   to DoOneStep  ;; have the turtle do one Turing step  ;; First, 'read the tape', i.e., based on the patch color here: let tapeValue GetTapeValue    ;; using the tapeValue and MyState, get the desired actions here:  ;; (the item commands extract the appropriate value from the list-of-lists) let myWrite item (tapeValue + 1) (item MyState WhatToWrite) let myMove item (tapeValue + 1) (item MyState HowToMove) let myNextState item (tapeValue + 1) (item MyState NextState)    ;; Write to the tape as appropriate SetTapeValue myWrite    ;; Move as appropriate if (myMove = 1) [MoveForward] if (myMove = -1) [MoveBackward]    ;; Go to the next state; check if it is a halt state.  ;; Update the global MachineState value set MachineState myNextState ifelse (myNextState < 0) [  ;; It's a halt state. The negative MachineState will signal the stop.  ;; Go back to the starting state so it can be re-run if desired. set MyState 0] [  ;; Not a halt state, so change to the desired next state set MyState myNextState ] end   to MoveForward  ;; move the turtle forward one cell, including line wrapping. set heading 90 ifelse (xcor = max-pxcor) [set xcor -1 * max-pxcor  ;; and go up a row if possible... otherwise die ifelse ycor = max-pxcor [ die ]  ;; tape too short - a somewhat crude end of things ;-) [set ycor ycor + 1] ] [jump 1] end   to MoveBackward  ;; move the turtle backward one cell, including line-wrapping. set heading -90 ifelse (xcor = -1 * max-pxcor) [ set xcor max-pxcor  ;; and go down a row... or die ifelse ycor = -1 * max-pxcor [ die ]  ;; tape too short - a somewhat crude end of things ;-) [set ycor ycor - 1] ] [jump 1] end   to-report GetTapeValue  ;; report the tape color equivalent value if (pcolor = ZeroColor) [report 0] if (pcolor = OneColor) [report 1] report -1 end   to SetTapeValue [ value ]  ;; write the appropriate color on the tape ifelse (value = 1) [set pcolor OneColor] [ ifelse (value = 0) [set pcolor ZeroColor][set pcolor BlankColor]] end     ;; - - - - - OK, here are the data for the various Turing programs... ;; Note that besdes settting the rules (array values) these sections can also ;; include commands to clear the tape, position the r/w head, adjust wait time, etc. to LoadTuringProgram    ;; A template of the rules structure: a list of lists  ;; E.g. values are given for States 0 to 4, when looking at Blank, Zero, One:  ;; For 2-symbol machines use Blank(-1) and One(1) and ignore the middle values (never see zero).  ;; Normal Halt will be state -1, the -9 default shows an unexpected halt.  ;; state 0 state 1 state 2 state 3 state 4 set WhatToWrite (list (list -1 0 1) (list -1 0 1) (list -1 0 1) (list -1 0 1) (list -1 0 1) ) set HowToMove (list (list 0 0 0) (list 0 0 0) (list 0 0 0) (list 0 0 0) (list 0 0 0) ) set NextState(list (list -9 -9 -9) (list -9 -9 -9) (list -9 -9 -9) (list -9 -9 -9) (list -9 -9 -9) )    ;; Fill the rules based on the selected case if (Turing_Program_Selection = "Simple Incrementor") [  ;; simple Incrementor - this is from the RosettaCode Universal Turing Machine page - very simple! set WhatToWrite (list (list 1 0 1) ) set HowToMove (list (list 0 0 1) ) set NextState (list (list -1 -9 0) ) ]    ;; Fill the rules based on the selected case if (Turing_Program_Selection = "Incrementor w/Return") [  ;; modified Incrementor: it returns to the first 1 on the left.  ;; This version allows the "Copy Ones to right" program to directly follow it.  ;; move right append one back to beginning set WhatToWrite (list (list -1 0 1) (list 1 0 1) (list -1 0 1) ) set HowToMove (list (list 1 0 1) (list 0 0 1) (list 1 0 -1) ) set NextState (list (list 1 -9 1) (list 2 -9 1) (list -1 -9 2) ) ]    ;; Fill the rules based on the selected case if (Turing_Program_Selection = "Copy Ones to right") [  ;; "Copy" from Wiki "Turing machine examples" page; slight mod so that it ends on first 1  ;; of the copy allowing Copy to be re-executed to create another copy.  ;; Has 5 states and uses Blank and 1 to make a copy of a string of ones;  ;; this can be run after runs of the "Incrementor w/Return".  ;; state 0 state 1 state 2 state 3 state 4 set WhatToWrite (list (list -1 0 -1) (list -1 0 1) (list 1 0 1) (list -1 0 1) (list 1 0 1) ) set HowToMove (list (list 1 0 1) (list 1 0 1) (list -1 0 1) (list -1 0 -1) (list 1 0 -1) ) set NextState (list (list -1 -9 1) (list 2 -9 1) (list 3 -9 2) (list 4 -9 3) (list 0 -9 4) ) ]    ;; Fill the rules based on the selected case if (Turing_Program_Selection = "Binary Counter") [  ;; Count in binary - can start on a blank space.  ;; States: start carry-1 back-to-beginning set WhatToWrite (list (list 1 1 0) (list 1 1 0) (list -1 0 1) ) set HowToMove (list (list 0 0 -1) (list 0 0 -1) (list -1 1 1) ) set NextState (list (list -1 -1 1) (list 2 2 1) (list -1 2 2) )  ;; Select line above from these two:  ;; can either count by 1 each time it is run:  ;; set NextState (list (list -1 -1 1) (list 2 2 1) (list -1 2 2) )  ;; or count forever once started:  ;; set NextState (list (list 0 0 1) (list 2 2 1) (list 0 2 2) ) set RealTimePerTick 0.2 ]   if (Turing_Program_Selection = "Busy-Beaver 3-State, 2-Sym") [  ;; from the RosettaCode.org Universal Turing Machine page  ;; state name: a b c set WhatToWrite (list (list 1 0 1) (list 1 0 1) (list 1 0 1) (list -1 0 1) (list -1 0 1) ) set HowToMove (list (list 1 0 -1) (list -1 0 1) (list -1 0 0) (list 0 0 0) (list 0 0 0) ) set NextState (list (list 1 -9 2) (list 0 -9 1) (list 1 -9 -1) (list -9 -9 -9) (list -9 -9 -9) )  ;; Clear the tape ask Patches [set pcolor BlankColor] ]    ;; should output 13 ones and take 107 steps to do it... if (Turing_Program_Selection = "Busy-Beaver 4-State, 2-Sym") [  ;; from the RosettaCode.org Universal Turing Machine page  ;; state name: A B C D set WhatToWrite (list (list 1 0 1) (list 1 0 -1) (list 1 0 1) (list 1 0 -1) (list -1 0 1) ) set HowToMove (list (list 1 0 -1) (list -1 0 -1) (list 1 0 -1) (list 1 0 1) (list 0 0 0) ) set NextState (list (list 1 -9 1) (list 0 -9 2) (list -1 -9 3) (list 3 -9 0) (list -9 -9 -9) )  ;; Clear the tape ask Patches [set pcolor BlankColor] ]    ;; This takes 38 steps to write 9 ones/zeroes if (Turing_Program_Selection = "Busy-Beaver 2-State, 3-Sym") [  ;; A B set WhatToWrite (list (list 0 1 0) (list 1 1 0) (list -1 0 1) (list -1 0 1) (list -1 0 1) ) set HowToMove (list (list 1 -1 1) (list -1 1 -1) (list 0 0 0) (list 0 0 0) (list 0 0 0) ) set NextState(list (list 1 1 -1) (list 0 1 1) (list -9 -9 -9) (list -9 -9 -9) (list -9 -9 -9) )  ;; Clear the tape ask Patches [set pcolor BlankColor] ]    ;; This only makes 501 ones and stops after 134,467 steps -- it does do that !!! if (Turing_Program_Selection = "Lazy-Beaver 5-State, 2-Sym") [  ;; from the RosettaCode.org Universal Turing Machine page  ;; state name: A0 B1 C2 D3 E4 set WhatToWrite (list (list 1 0 -1) (list 1 0 1) (list 1 0 -1) (list -1 0 1) (list 1 0 1) ) set HowToMove (list (list 1 0 -1) (list 1 0 1) (list -1 0 1) (list 1 0 1) (list -1 0 1) ) set NextState (list (list 1 -9 2) (list 2 -9 3) (list 0 -9 1) (list 4 -9 -1) (list 2 -9 0) )  ;; Clear the tape ask Patches [set pcolor BlankColor]  ;; Looks like it goes much more forward than back on the tape  ;; so start the head just a row from the bottom: ask turtles [setxy 0 -1 * max-pxcor + 1]  ;; and go faster set RealTimePerTick 0.02 ]    ;; The rest have large outputs and run for a long time, so I haven't confirmed  ;; that they work as advertised...    ;; This is the 5,2 record holder: 4098 ones in 47,176,870 steps.  ;; With max-pxcor of 14 and offset r/w head start (below), this will  ;; run off the tape at about 150,000+steps... if (Turing_Program_Selection = "Busy-Beaver 5-State, 2-Sym") [  ;; from the RosettaCode.org Universal Turing Machine page  ;; state name: A B C D E set WhatToWrite (list (list 1 0 1) (list 1 0 1) (list 1 0 -1) (list 1 0 1) (list 1 0 -1) ) set HowToMove (list (list 1 0 -1) (list 1 0 1) (list 1 0 -1) (list -1 0 -1) (list 1 0 -1) ) set NextState (list (list 1 -9 2) (list 2 -9 1) (list 3 -9 4) (list 0 -9 3) (list -1 -9 0) )  ;; Clear the tape ask Patches [set pcolor BlankColor]  ;; Writes more backward than forward, so start a few rows from the top: ask turtles [setxy 0 max-pxcor - 3]  ;; and go faster set RealTimePerTick 0.02 ]   if (Turing_Program_Selection = "Lazy-Beaver 3-State, 3-Sym") [  ;; This should write 5600 ones/zeros and take 29,403,894 steps.  ;; Ran it to 175,000+ steps and only covered 1/2 of the cells (w/max-pxcor = 14)...  ;; state name: A B C set WhatToWrite (list (list 0 1 0) (list 1 -1 0) (list 0 1 0) (list -1 0 1) (list -1 0 1) ) set HowToMove (list (list 1 1 -1) (list -1 1 1) (list 1 -1 1) (list 0 0 0) (list 0 0 0) ) set NextState (list (list 1 0 0) (list 2 2 1) (list -1 0 1) (list -9 -9 -9) (list -9 -9 -9) )  ;; Clear the tape ask Patches [set pcolor BlankColor]  ;; It goes much more forward than back on the tape  ;; so start the head just a row from the bottom: ask turtles [setxy 0 -1 * max-pxcor + 1]  ;; and go faster set RealTimePerTick 0.02 ]   if (Turing_Program_Selection = "Busy-Beaver 3-State, 3-Sym") [  ;; This should write 374,676,383 ones/zeros and take 119,112,334,170,342,540 (!!!) steps.  ;; Rn it to ~ 175,000 steps covering about 2/3 of the max-pxcor=14 cells.  ;; state name: A B C set WhatToWrite (list (list 0 1 0) (list -1 1 0) (list 0 0 0) (list -1 0 1) (list -1 0 1) ) set HowToMove (list (list 1 -1 -1) (list -1 1 -1) (list 1 1 1) (list 0 0 0) (list 0 0 0) ) set NextState (list (list 1 0 2) (list 0 1 1) (list -1 0 2) (list -9 -9 -9) (list -9 -9 -9) )  ;; Clear the tape ask Patches [set pcolor BlankColor]  ;; Writes more backward than forward, so start a rowish from the top: ask turtles [setxy 0 max-pxcor - 1]  ;; and go faster set RealTimePerTick 0.02 ]    ;; in all cases reset the machine state to 0: ask turtles [set MyState 0] set MachineState 0  ;; and the ticks reset-ticks   end  
http://rosettacode.org/wiki/Totient_function
Totient function
The   totient   function is also known as:   Euler's totient function   Euler's phi totient function   phi totient function   Φ   function   (uppercase Greek phi)   φ    function   (lowercase Greek phi) Definitions   (as per number theory) The totient function:   counts the integers up to a given positive integer   n   that are relatively prime to   n   counts the integers   k   in the range   1 ≤ k ≤ n   for which the greatest common divisor   gcd(n,k)   is equal to   1   counts numbers   ≤ n   and   prime to   n If the totient number   (for N)   is one less than   N,   then   N   is prime. Task Create a   totient   function and:   Find and display   (1 per line)   for the 1st   25   integers:   the integer   (the index)   the totient number for that integer   indicate if that integer is prime   Find and display the   count   of the primes up to          100   Find and display the   count   of the primes up to       1,000   Find and display the   count   of the primes up to     10,000   Find and display the   count   of the primes up to   100,000     (optional) Show all output here. Related task   Perfect totient numbers Also see   Wikipedia: Euler's totient function.   MathWorld: totient function.   OEIS: Euler totient function phi(n).
#Nim
Nim
import strformat   func totient(n: int): int = var tot = n var nn = n var i = 2 while i * i <= nn: if nn mod i == 0: while nn mod i == 0: nn = nn div i dec tot, tot div i if i == 2: i = 1 inc i, 2 if nn > 1: dec tot, tot div nn tot   echo " n φ prime" echo "---------------" var count = 0 for n in 1..25: let tot = totient(n) let isPrime = n - 1 == tot if isPrime: inc count echo fmt"{n:2} {tot:2} {isPrime}" echo "" echo fmt"Number of primes up to {25:>6} = {count:>4}" for n in 26..100_000: let tot = totient(n) if tot == n - 1: inc count if n == 100 or n == 1000 or n mod 10_000 == 0: echo fmt"Number of primes up to {n:>6} = {count:>4}"
http://rosettacode.org/wiki/Topswops
Topswops
Topswops is a card game created by John Conway in the 1970's. Assume you have a particular permutation of a set of   n   cards numbered   1..n   on both of their faces, for example the arrangement of four cards given by   [2, 4, 1, 3]   where the leftmost card is on top. A round is composed of reversing the first   m   cards where   m   is the value of the topmost card. Rounds are repeated until the topmost card is the number   1   and the number of swaps is recorded. For our example the swaps produce: [2, 4, 1, 3] # Initial shuffle [4, 2, 1, 3] [3, 1, 2, 4] [2, 1, 3, 4] [1, 2, 3, 4] For a total of four swaps from the initial ordering to produce the terminating case where   1   is on top. For a particular number   n   of cards,   topswops(n)   is the maximum swaps needed for any starting permutation of the   n   cards. Task The task is to generate and show here a table of   n   vs   topswops(n)   for   n   in the range   1..10   inclusive. Note Topswops   is also known as   Fannkuch   from the German word   Pfannkuchen   meaning   pancake. Related tasks   Number reversal game   Sorting algorithms/Pancake sort
#Tcl
Tcl
package require struct::list   proc swap {listVar} { upvar 1 $listVar list set n [lindex $list 0] for {set i 0; set j [expr {$n-1}]} {$i<$j} {incr i;incr j -1} { set tmp [lindex $list $i] lset list $i [lindex $list $j] lset list $j $tmp } }   proc swaps {list} { for {set i 0} {[lindex $list 0] > 1} {incr i} { swap list } return $i }   proc topswops list { set n 0  ::struct::list foreachperm p $list { set n [expr {max($n,[swaps $p])}] } return $n }   proc topswopsTo n { puts "n\ttopswops(n)" for {set i 1} {$i <= $n} {incr i} { puts $i\t[topswops [lappend list $i]] } } topswopsTo 10
http://rosettacode.org/wiki/Trigonometric_functions
Trigonometric functions
Task If your language has a library or built-in functions for trigonometry, show examples of:   sine   cosine   tangent   inverses   (of the above) using the same angle in radians and degrees. For the non-inverse functions,   each radian/degree pair should use arguments that evaluate to the same angle   (that is, it's not necessary to use the same angle for all three regular functions as long as the two sine calls use the same angle). For the inverse functions,   use the same number and convert its answer to radians and degrees. If your language does not have trigonometric functions available or only has some available,   write functions to calculate the functions based on any   known approximation or identity.
#GAP
GAP
# GAP has an improved floating-point support since version 4.5   Pi := Acos(-1.0);   # Or use the built-in constant: Pi := FLOAT.PI;   r := Pi / 5.0; d := 36;   Deg := x -> x * Pi / 180;   Sin(r); Asin(last); Sin(Deg(d)); Asin(last); Cos(r); Acos(last); Cos(Deg(d)); Acos(last); Tan(r); Atan(last); Tan(Deg(d)); Atan(last);
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#PL.2FI
PL/I
  Trabb: Procedure options (main); /* 11 November 2013 */   declare (i, n) fixed binary; declare s fixed (5,1) controlled; declare g fixed (15,5);   put ('Please type 11 values:'); do i = 1 to 11; allocate s; get (s); put (s); end; put skip(2) ('Results:'); do i = 1 to 11; g = f(s); put skip list (s); if g > 400 then put ('Too large'); else put (g); free s; end;   f: procedure (x) returns (fixed(15,5)); declare x fixed (5,1); return (sqrt(abs(x)) + 5*x**3); end f;   end Trabb;  
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#PL.2FM
PL/M
TPK: DO; /* external I/O and real mathematical routines */ WRITE$STRING: PROCEDURE( S ) EXTERNAL; DECLARE S POINTER; END; WRITE$REAL: PROCEDURE( R ) EXTERNAL; DECLARE R REAL; END; WRITE$NL: PROCEDURE EXTERNAL; END; READ$REAL: PROCEDURE( R ) REAL EXTERNAL; DECLARE R POINTER; END; REAL$ABS: PROCEDURE( R ) REAL EXTERNAL; DECLARE R REAL; END; REAL$SQRT: PROCEDURE( R ) REAL EXTERNAL; DECLARE R REAL; END; /* end external routines */   F: PROCEDURE( T ) REAL; DECLARE T REAL; RETURN REAL$SQRT(REAL$ABS(T))+5*T*T*T; END F; MAIN: PROCEDURE; DECLARE Y REAL, A( 11 ) REAL, I INTEGER; DO I = 0 TO 10; CALL READ$REAL( @A( I ) ); END; DO I = 10 TO 0 BY -1; Y = F( A( I ) ); IF Y > 400.0 THEN CALL WRITE$STRING( @( 'TOO LARGE', 0 ) ); ELSE CALL WRITE$REAL( Y ); CALL WRITE$NL(); END; END MAIN;   END TPK;
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#PowerShell
PowerShell
  function Get-Tpk { [CmdletBinding()] [OutputType([PSCustomObject])] Param ( [Parameter(Mandatory=$true, ValueFromPipeline=$true, ValueFromPipelineByPropertyName=$true, Position=0)] [double] $Number )   Begin { function Get-TpkFunction ([double]$Number) { [Math]::Pow([Math]::Abs($Number),(0.5)) + 5 * [Math]::Pow($Number,3) }   [object[]]$output = @() } Process { $Number | ForEach-Object { $n = Get-TpkFunction $_   if ($n -le 400) { $result = $n } else { $result = "Overflow" } }   $output += [PSCustomObject]@{ Number = $Number Result = $result } } End { [Array]::Reverse($output) $output } }  
http://rosettacode.org/wiki/Truth_table
Truth table
A truth table is a display of the inputs to, and the output of a Boolean function organized as a table where each row gives one combination of input values and the corresponding value of the function. Task Input a Boolean function from the user as a string then calculate and print a formatted truth table for the given function. (One can assume that the user input is correct). Print and show output for Boolean functions of two and three input variables, but any program should not be limited to that many variables in the function. Either reverse-polish or infix notation expressions are allowed. Related tasks   Boolean values   Ternary logic See also   Wolfram MathWorld entry on truth tables.   some "truth table" examples from Google.
#XBasic
XBasic
  PROGRAM "truthtables" VERSION "0.001"   $$MaxTop = 80   TYPE VARIABLE STRING*1 .name SBYTE .value END TYPE   TYPE STACKOFBOOL SSHORT .top SBYTE .elements[$$MaxTop] END TYPE   DECLARE FUNCTION Entry() INTERNAL FUNCTION IsOperator(c$) INTERNAL FUNCTION VariableIndex(c$) INTERNAL FUNCTION SetVariables(pos%) INTERNAL FUNCTION ProcessExpression() INTERNAL FUNCTION EvaluateExpression()   ' Stack manipulation functions INTERNAL FUNCTION IsFull(STACKOFBOOL @s) INTERNAL FUNCTION IsEmpty(STACKOFBOOL @s) INTERNAL FUNCTION Peek(STACKOFBOOL @s) INTERNAL FUNCTION Push(STACKOFBOOL @s, val@) INTERNAL FUNCTION Pop(STACKOFBOOL @s) INTERNAL FUNCTION MakeEmpty(STACKOFBOOL @s) INTERNAL FUNCTION ElementsCount(STACKOFBOOL @s)   FUNCTION Entry() SHARED VARIABLE variables[] SHARED variablesLength% SHARED expression$   DIM variables[23] PRINT "Accepts single-character variables (except for 'T' and 'F'," PRINT "which specify explicit true or false values), postfix, with" PRINT "&|!^ for and, or, not, xor, respectively; optionally" PRINT "seperated by space. Just enter nothing to quit." DO PRINT expression$ = INLINE$("Boolean expression: ") ProcessExpression() IF LEN(expression$) = 0 THEN EXIT DO END IF variablesLength% = 0 FOR i% = 0 TO LEN(expression$) - 1 e$ = CHR$(expression${i%}) IF (!IsOperator(e$)) && (e$ <> "T") && (e$ <> "F") && (VariableIndex(e$) = -1) THEN variables[variablesLength%].name = LEFT$(e$, 1) variables[variablesLength%].value = $$FALSE INC variablesLength% END IF NEXT i% PRINT IF variablesLength% = 0 THEN PRINT "No variables were entered." ELSE FOR i% = 0 TO variablesLength% - 1 PRINT variables[i%].name; " "; NEXT i% PRINT expression$ PRINT CHR$(ASC("="), variablesLength% * 3 + LEN(expression$)) SetVariables(0) END IF LOOP END FUNCTION   ' Removes space and converts to upper case FUNCTION ProcessExpression() SHARED expression$ ' exprTmp$ = "" FOR i% = 0 TO LEN(expression$) - 1 IF CHR$(expression${i%}) <> " " THEN exprTmp$ = exprTmp$ + UCASE$(CHR$(expression${i%})) END IF NEXT i% expression$ = exprTmp$ END FUNCTION   FUNCTION IsOperator(c$) RETURN (c$ = "&") || (c$ = "|") || (c$ = "!") || (c$ = "^") END FUNCTION   FUNCTION VariableIndex(c$) SHARED VARIABLE variables[] SHARED variablesLength% ' FOR i% = 0 TO variablesLength% - 1 IF variables[i%].name = c$ THEN RETURN i% END IF NEXT i% RETURN -1 END FUNCTION   FUNCTION SetVariables(pos%) SHARED VARIABLE variables[] SHARED variablesLength% ' SELECT CASE TRUE CASE pos% > variablesLength%: PRINT PRINT "Argument to SetVariables cannot be greater than the number of variables." QUIT(1) CASE pos% = variablesLength%: FOR i% = 0 TO variablesLength% - 1 IF variables[i%].value THEN PRINT "T "; ELSE PRINT "F "; END IF NEXT i% IF EvaluateExpression() THEN PRINT "T" ELSE PRINT "F" END IF CASE ELSE: variables[pos%].value = $$FALSE SetVariables(pos% + 1) variables[pos%].value = $$TRUE SetVariables(pos% + 1) END SELECT END FUNCTION   FUNCTION EvaluateExpression() SHARED VARIABLE variables[] SHARED expression$ STACKOFBOOL s ' MakeEmpty(@s) FOR i% = 0 TO LEN(expression$) - 1 e$ = CHR$(expression${i%}) vi% = VariableIndex(e$) SELECT CASE TRUE CASE e$ = "T": Push(@s, $$TRUE) CASE e$ = "F": Push(@s, $$FALSE) CASE vi% >= 0: Push(@s, variables[vi%].value) CASE ELSE: SELECT CASE e$ CASE "&": Push(@s, Pop(@s) & Pop(@s)) CASE "|": Push(@s, Pop(@s) | Pop(@s)) CASE "!": Push(@s, !Pop(@s)) CASE "^": Push(@s, Pop(@s) ^ Pop(@s)) CASE ELSE: PRINT PRINT "Non-conformant character "; e$; " in expression."; QUIT(1) END SELECT END SELECT NEXT i% IF ElementsCount(@s) <> 1 THEN PRINT PRINT "Stack should contain exactly one element." QUIT(1) END IF RETURN Peek(@s) END FUNCTION   FUNCTION IsFull(STACKOFBOOL s) RETURN s.top = $$MaxTop END FUNCTION   FUNCTION IsEmpty(STACKOFBOOL s) RETURN s.top = -1 END FUNCTION   FUNCTION Peek(STACKOFBOOL s) IF !IsEmpty(@s) THEN RETURN s.elements[s.top] ELSE PRINT "Stack is empty." QUIT(1) END IF END FUNCTION   FUNCTION Push(STACKOFBOOL s, val@) IF !IsFull(@s) THEN INC s.top s.elements[s.top] = val@ ELSE PRINT "Stack is full." QUIT(1) END IF END FUNCTION   FUNCTION Pop(STACKOFBOOL s) IF !IsEmpty(@s) THEN res@ = s.elements[s.top] DEC s.top RETURN res@ ELSE PRINT PRINT "Stack is empty." QUIT(1) END IF END FUNCTION   FUNCTION MakeEmpty(STACKOFBOOL s) s.top = -1 END FUNCTION   FUNCTION ElementsCount(STACKOFBOOL s) RETURN s.top + 1 END FUNCTION END PROGRAM  
http://rosettacode.org/wiki/Truncatable_primes
Truncatable primes
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 739, 73, and 7 formed by removing digits from its right are also prime. No zeroes are allowed in truncatable primes. Task The task is to find the largest left-truncatable and right-truncatable primes less than one million (base 10 is implied). Related tasks Find largest left truncatable prime in a given base Sieve of Eratosthenes See also Truncatable Prime from MathWorld.]
#PL.2FI
PL/I
  tp: procedure options (main); declare primes(1000000) bit (1); declare max_primes fixed binary (31); declare (i, k) fixed binary (31);   max_primes = hbound(primes, 1); call sieve;   /* Now search for primes that are right-truncatable. */ call right_truncatable;   /* Now search for primes that are left-truncatable. */ call left_truncatable;   right_truncatable: procedure; declare direction bit (1); declare (i, k) fixed binary (31);   test_truncatable: do i = max_primes to 2 by -1; if primes(i) then /* it's a prime */ do; k = i/10; do while (k > 0); if ^primes(k) then iterate test_truncatable; k = k/10; end; put skip list (i || ' is right-truncatable'); return; end; end; end right_truncatable;   left_truncatable: procedure; declare direction bit (1); declare (i, k, d, e) fixed binary (31);   test_truncatable: do i = max_primes to 2 by -1; if primes(i) then /* it's a prime */ do; k = i; do d = 100000 repeat d/10 until (d = 10); e = k/d; k = k - e*d; if e = 0 then iterate test_truncatable; if ^primes(k) then iterate test_truncatable; end; put skip list (i || ' is left-truncatable'); return; end; end; end left_truncatable;   sieve: procedure; declare (i, j) fixed binary (31);   primes = '1'b; primes(1) = '0'b;   do i = 2 to sqrt(max_primes); do j = i+i to max_primes by i; primes(j) = '0'b; end; end; end sieve;   end tp;  
http://rosettacode.org/wiki/Truncatable_primes
Truncatable primes
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 739, 73, and 7 formed by removing digits from its right are also prime. No zeroes are allowed in truncatable primes. Task The task is to find the largest left-truncatable and right-truncatable primes less than one million (base 10 is implied). Related tasks Find largest left truncatable prime in a given base Sieve of Eratosthenes See also Truncatable Prime from MathWorld.]
#PowerShell
PowerShell
function IsPrime ( [int] $num ) { $isprime = @{} 2..[math]::sqrt($num) | Where-Object { $isprime[$_] -eq $null } | ForEach-Object { $_ $isprime[$_] = $true for ( $i=$_*$_ ; $i -le $num; $i += $_ ) { $isprime[$i] = $false } } 2..$num | Where-Object { $isprime[$_] -eq $null } }   function Truncatable ( [int] $num ) { $declen = [math]::abs($num).ToString().Length $primes = @() $ltprimes = @{} $rtprimes = @{} 1..$declen | ForEach-Object { $ltprimes[$_]=@{}; $rtprimes[$_]=@{} } IsPrime $num | ForEach-Object { $lastltprime = 2 $lastrtprime = 2 } { $curprim = $_ $curdeclen = $curprim.ToString().Length $primes += $curprim if( $curdeclen -eq 1 ) { $ltprimes[1][$curprim] = $true $rtprimes[1][$curprim] = $true $lastltprime = $curprim $lastrtprime = $curprim } else { $curmod = $curprim % [math]::pow(10,$curdeclen - 1) $curdiv = [math]::floor($curprim / 10) if( $ltprimes[$curdeclen - 1][[int]$curmod] ) { $ltprimes[$curdeclen][$curprim] = $true $lastltprime = $curprim } if( $rtprimes[$curdeclen - 1][[int]$curdiv] ) { $rtprimes[$curdeclen][$curprim] = $true $lastrtprime = $curprim } } if( ( $ltprimes[$curdeclen - 2].Keys.count -gt 0 ) -and ( $ltprimes[$curdeclen - 1].Keys.count -gt 0 ) ) { $ltprimes[$curdeclen -2] = @{} } if( ( $rtprimes[$curdeclen - 2].Keys.count -gt 0 ) -and ( $rtprimes[$curdeclen - 1].Keys.count -gt 0 ) ) { $rtprimes[$curdeclen -2] = @{} } } { "Largest Left Truncatable Prime: $lastltprime" "Largest Right Truncatable Prime: $lastrtprime" } }
http://rosettacode.org/wiki/Tree_traversal
Tree traversal
Task Implement a binary tree where each node carries an integer,   and implement:   pre-order,   in-order,   post-order,     and   level-order   traversal. Use those traversals to output the following tree: 1 / \ / \ / \ 2 3 / \ / 4 5 6 / / \ 7 8 9 The correct output should look like this: preorder: 1 2 4 7 5 3 6 8 9 inorder: 7 4 2 5 1 8 6 9 3 postorder: 7 4 5 2 8 9 6 3 1 level-order: 1 2 3 4 5 6 7 8 9 See also   Wikipedia article:   Tree traversal.
#E
E
def btree := [1, [2, [4, [7, null, null], null], [5, null, null]], [3, [6, [8, null, null], [9, null, null]], null]]   def backtrackingOrder(node, pre, mid, post) { switch (node) { match ==null {} match [value, left, right] { pre(value) backtrackingOrder(left, pre, mid, post) mid(value) backtrackingOrder(right, pre, mid, post) post(value) } } }   def levelOrder(root, func) { var level := [root].diverge() while (level.size() > 0) { for node in level.removeRun(0) { switch (node) { match ==null {} match [value, left, right] { func(value) level.push(left) level.push(right) } } } } }   print("preorder: ") backtrackingOrder(btree, fn v { print(" ", v) }, fn _ {}, fn _ {}) println()   print("inorder: ") backtrackingOrder(btree, fn _ {}, fn v { print(" ", v) }, fn _ {}) println()   print("postorder: ") backtrackingOrder(btree, fn _ {}, fn _ {}, fn v { print(" ", v) }) println()   print("level-order:") levelOrder(btree, fn v { print(" ", v) }) println()
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Ceylon
Ceylon
shared void tokenizeAString() { value input = "Hello,How,Are,You,Today"; value tokens = input.split(','.equals); print(".".join(tokens)); }
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#CFEngine
CFEngine
bundle agent main { reports: "${with}" with => join(".", splitstring("Hello,How,Are,You,Today", ",", 99)); }  
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#C
C
#include <stdio.h> #include <time.h>   int identity(int x) { return x; }   int sum(int s) { int i; for(i=0; i < 1000000; i++) s += i; return s; }   #ifdef CLOCK_PROCESS_CPUTIME_ID /* cpu time in the current process */ #define CLOCKTYPE CLOCK_PROCESS_CPUTIME_ID #else /* this one should be appropriate to avoid errors on multiprocessors systems */ #define CLOCKTYPE CLOCK_MONOTONIC #endif   double time_it(int (*action)(int), int arg) { struct timespec tsi, tsf;   clock_gettime(CLOCKTYPE, &tsi); action(arg); clock_gettime(CLOCKTYPE, &tsf);   double elaps_s = difftime(tsf.tv_sec, tsi.tv_sec); long elaps_ns = tsf.tv_nsec - tsi.tv_nsec; return elaps_s + ((double)elaps_ns) / 1.0e9; }   int main() { printf("identity (4) takes %lf s\n", time_it(identity, 4)); printf("sum (4) takes %lf s\n", time_it(sum, 4)); return 0; }
http://rosettacode.org/wiki/Top_rank_per_group
Top rank per group
Task Find the top   N   salaries in each department,   where   N   is provided as a parameter. Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source: Employee Name,Employee ID,Salary,Department Tyler Bennett,E10297,32000,D101 John Rappl,E21437,47000,D050 George Woltman,E00127,53500,D101 Adam Smith,E63535,18000,D202 Claire Buckman,E39876,27800,D202 David McClellan,E04242,41500,D101 Rich Holcomb,E01234,49500,D202 Nathan Adams,E41298,21900,D050 Richard Potter,E43128,15900,D101 David Motsinger,E27002,19250,D202 Tim Sampair,E03033,27000,D101 Kim Arlich,E10001,57000,D190 Timothy Grove,E16398,29900,D190
#E
E
/** Turn a list of arrays into a list of maps with the given keys. */ def addKeys(keys, rows) { def res := [].diverge() for row in rows { res.push(__makeMap.fromColumns(keys, row)) } return res.snapshot() }   def data := addKeys( ["name", "id", "salary", "dept"], [["Tyler Bennett", "E10297", 32000, "D101"], ["John Rappl", "E21437", 47000, "D050"], ["George Woltman", "E00127", 53500, "D101"], ["Adam Smith", "E63535", 18000, "D202"], ["Claire Buckman", "E39876", 27800, "D202"], ["David McClellan", "E04242", 41500, "D101"], ["Rich Holcomb", "E01234", 49500, "D202"], ["Nathan Adams", "E41298", 21900, "D050"], ["Richard Potter", "E43128", 15900, "D101"], ["David Motsinger", "E27002", 19250, "D202"], ["Tim Sampair", "E03033", 27000, "D101"], ["Kim Arlich", "E10001", 57000, "D190"], ["Timothy Grove", "E16398", 29900, "D190"]])   def topSalaries(n, out) { var groups := [].asMap() for row in data { def [=> salary, => dept] | _ := row def top := groups.fetch(dept, fn {[]}).with([-salary, row]).sort() groups with= (dept, top.run(0, top.size().min(n))) } for dept => group in groups.sortKeys() { out.println(`Department $dept`) out.println(`---------------`) for [_, row] in group { out.println(`${row["id"]} $$${row["salary"]} ${row["name"]}`) } out.println() } }
http://rosettacode.org/wiki/Tic-tac-toe
Tic-tac-toe
Task Play a game of tic-tac-toe. Ensure that legal moves are played and that a winning position is notified. Tic-tac-toe   is also known as:   naughts and crosses   tic tac toe   tick tack toe   three in a row   tres en rayo       and   Xs  and  Os See also   MathWorld™, Tic-Tac-Toe game.   Wikipedia tic-tac-toe.
#Batch_File
Batch File
@echo off setlocal enabledelayedexpansion :newgame set a1=1 set a2=2 set a3=3 set a4=4 set a5=5 set a6=6 set a7=7 set a8=8 set a9=9 set ll=X set /a zz=0 :display1 cls echo Player: %ll% echo %a7%_%a8%_%a9% echo %a4%_%a5%_%a6% echo %a1%_%a2%_%a3% set /p myt=Where would you like to go (choose a number from 1-9 and press enter)? if !a%myt%! equ %myt% ( set a%myt%=%ll% goto check ) goto display1 :check set /a zz=%zz%+1 if %zz% geq 9 goto newgame if %a7%+%a8%+%a9% equ %ll%+%ll%+%ll% goto win if %a4%+%a5%+%a6% equ %ll%+%ll%+%ll% goto win if %a1%+%a2%+%a3% equ %ll%+%ll%+%ll% goto win if %a7%+%a5%+%a3% equ %ll%+%ll%+%ll% goto win if %a1%+%a5%+%a9% equ %ll%+%ll%+%ll% goto win if %a7%+%a4%+%a1% equ %ll%+%ll%+%ll% goto win if %a8%+%a5%+%a2% equ %ll%+%ll%+%ll% goto win if %a9%+%a6%+%a3% equ %ll%+%ll%+%ll% goto win goto %ll% :X set ll=O goto display1 :O set ll=X goto display1 :win echo %ll% wins! pause goto newgame  
http://rosettacode.org/wiki/Towers_of_Hanoi
Towers of Hanoi
Task Solve the   Towers of Hanoi   problem with recursion.
#BBC_BASIC
BBC BASIC
DIM Disc$(13),Size%(3) FOR disc% = 1 TO 13 Disc$(disc%) = STRING$(disc%," ")+STR$disc%+STRING$(disc%," ") IF disc%>=10 Disc$(disc%) = MID$(Disc$(disc%),2) Disc$(disc%) = CHR$17+CHR$(128+disc%-(disc%>7))+Disc$(disc%)+CHR$17+CHR$128 NEXT disc%   MODE 3 OFF ndiscs% = 13 FOR n% = ndiscs% TO 1 STEP -1 PROCput(n%,1) NEXT INPUT TAB(0,0) "Press Enter to start" dummy$ PRINT TAB(0,0) SPC(20); PROChanoi(ndiscs%,1,2,3) VDU 30 END   DEF PROChanoi(a%,b%,c%,d%) IF a%=0 ENDPROC PROChanoi(a%-1,b%,d%,c%) PROCtake(a%,b%) PROCput(a%,c%) PROChanoi(a%-1,d%,c%,b%) ENDPROC   DEF PROCput(disc%,peg%) PRINTTAB(13+26*(peg%-1)-disc%,20-Size%(peg%))Disc$(disc%); Size%(peg%) = Size%(peg%)+1 ENDPROC   DEF PROCtake(disc%,peg%) Size%(peg%) = Size%(peg%)-1 PRINTTAB(13+26*(peg%-1)-disc%,20-Size%(peg%))STRING$(2*disc%+1," "); ENDPROC
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#Java
Java
public class ThueMorse {   public static void main(String[] args) { sequence(6); }   public static void sequence(int steps) { StringBuilder sb1 = new StringBuilder("0"); StringBuilder sb2 = new StringBuilder("1"); for (int i = 0; i < steps; i++) { String tmp = sb1.toString(); sb1.append(sb2); sb2.append(tmp); } System.out.println(sb1); } }
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#JavaScript
JavaScript
(function(steps) { 'use strict'; var i, tmp, s1 = '0', s2 = '1'; for (i = 0; i < steps; i++) { tmp = s1; s1 += s2; s2 += tmp; } console.log(s1); })(6);
http://rosettacode.org/wiki/Tonelli-Shanks_algorithm
Tonelli-Shanks algorithm
This page uses content from Wikipedia. The original article was at Tonelli-Shanks algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In computational number theory, the Tonelli–Shanks algorithm is a technique for solving for x in a congruence of the form: x2 ≡ n (mod p) where n is an integer which is a quadratic residue (mod p), p is an odd prime, and x,n ∈ Fp where Fp = {0, 1, ..., p - 1}. It is used in cryptography techniques. To apply the algorithm, we need the Legendre symbol: The Legendre symbol (a | p) denotes the value of a(p-1)/2 (mod p). (a | p) ≡ 1    if a is a square (mod p) (a | p) ≡ -1    if a is not a square (mod p) (a | p) ≡ 0    if a ≡ 0 (mod p) Algorithm pseudo-code All ≡ are taken to mean (mod p) unless stated otherwise. Input: p an odd prime, and an integer n . Step 0: Check that n is indeed a square: (n | p) must be ≡ 1 . Step 1: By factoring out powers of 2 from p - 1, find q and s such that p - 1 = q2s with q odd . If p ≡ 3 (mod 4) (i.e. s = 1), output the two solutions r ≡ ± n(p+1)/4 . Step 2: Select a non-square z such that (z | p) ≡ -1 and set c ≡ zq . Step 3: Set r ≡ n(q+1)/2, t ≡ nq, m = s . Step 4: Loop the following: If t ≡ 1, output r and p - r . Otherwise find, by repeated squaring, the lowest i, 0 < i < m , such that t2i ≡ 1 . Let b ≡ c2(m - i - 1), and set r ≡ rb, t ≡ tb2, c ≡ b2 and m = i . Task Implement the above algorithm. Find solutions (if any) for n = 10 p = 13 n = 56 p = 101 n = 1030 p = 10009 n = 1032 p = 10009 n = 44402 p = 100049 Extra credit n = 665820697 p = 1000000009 n = 881398088036 p = 1000000000039 n = 41660815127637347468140745042827704103445750172002 p = 10^50 + 577 See also Modular exponentiation Cipolla's algorithm
#Sidef
Sidef
func tonelli(n, p) { legendre(n, p) == 1 || die "not a square (mod p)" var q = p-1 var s = valuation(q, 2) s == 1 ? return(powmod(n, (p + 1) >> 2, p)) : (q >>= s) var c = powmod(2 ..^ p -> first {|z| legendre(z, p) == -1}, q, p) var r = powmod(n, (q + 1) >> 1, p) var t = powmod(n, q, p) var m = s var t2 = 0 while (!p.divides(t - 1)) { t2 = ((t * t) % p) var b for i in (1 ..^ m) { if (p.divides(t2 - 1)) { b = powmod(c, 1 << (m - i - 1), p) m = i break } t2 = ((t2 * t2) % p) }   r = ((r * b) % p) c = ((b * b) % p) t = ((t * c) % p) } return r }   var tests = [ [10, 13], [56, 101], [1030, 10009], [44402, 100049], [665820697, 1000000009], [881398088036, 1000000000039], [41660815127637347468140745042827704103445750172002, 10**50 + 577], ]   for n,p in tests { var r = tonelli(n, p) assert((r*r - n) % p == 0) say "Roots of #{n} are (#{r}, #{p-r}) mod #{p}" }
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#jq
jq
# Tokenize the input using the string "escape" as the prefix escape string def tokenize(separator; escape):   # Helper functions: # mapper/1 is like map/1, but for each element, $e, in the input array, # if $e is an array, then it is inserted, # otherwise the elements of ($e|f) are inserted. def mapper(f): reduce .[] as $e ( []; if ($e|type) == "array" then . + [$e] else . + ($e | f) end ) ;   # interpolate x def interpolate(x): reduce .[] as $i ([]; . + [$i, x]) | .[0:-1];   def splitstring(s; twixt): if type == "string" then split(s) | interpolate(twixt) else . end;   # concatenate sequences of non-null elements: def reform: reduce .[] as $x ([]; if $x == null and .[-1] == null then .[0:-1] + ["", null] elif $x == null then . + [null] elif .[-1] == null then .[0:-1] + [$x] else .[0:-1] + [ .[-1] + $x ] end) | if .[-1] == null then .[-1] = "" else . end;   splitstring(escape + escape; [escape]) | mapper( splitstring( escape + separator; [separator]) ) | mapper( splitstring( separator; null ) ) | map( if type == "string" then split(escape) else . end) | flatten | reform ;
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Julia
Julia
function tokenize2(s::AbstractString, sep::Char, esc::Char) SPE = "\ufffe" SPF = "\uffff" s = replace(s, "$esc$esc", SPE) |> s -> replace(s, "$esc$sep", SPF) |> s -> last(s) == esc ? string(replace(s[1:end-1], esc, ""), esc) : replace(s, esc, "") return map(split(s, sep)) do token token = replace(token, SPE, esc) return replace(token, SPF, sep) end end   @show tokenize2("one^|uno||three^^^^|four^^^|^cuatro|", '|', '^')
http://rosettacode.org/wiki/Total_circles_area
Total circles area
Total circles area You are encouraged to solve this task according to the task description, using any language you may know. Example circles Example circles filtered Given some partially overlapping circles on the plane, compute and show the total area covered by them, with four or six (or a little more) decimal digits of precision. The area covered by two or more disks needs to be counted only once. One point of this Task is also to compare and discuss the relative merits of various solution strategies, their performance, precision and simplicity. This means keeping both slower and faster solutions for a language (like C) is welcome. To allow a better comparison of the different implementations, solve the problem with this standard dataset, each line contains the x and y coordinates of the centers of the disks and their radii   (11 disks are fully contained inside other disks): xc yc radius 1.6417233788 1.6121789534 0.0848270516 -1.4944608174 1.2077959613 1.1039549836 0.6110294452 -0.6907087527 0.9089162485 0.3844862411 0.2923344616 0.2375743054 -0.2495892950 -0.3832854473 1.0845181219 1.7813504266 1.6178237031 0.8162655711 -0.1985249206 -0.8343333301 0.0538864941 -1.7011985145 -0.1263820964 0.4776976918 -0.4319462812 1.4104420482 0.7886291537 0.2178372997 -0.9499557344 0.0357871187 -0.6294854565 -1.3078893852 0.7653357688 1.7952608455 0.6281269104 0.2727652452 1.4168575317 1.0683357171 1.1016025378 1.4637371396 0.9463877418 1.1846214562 -0.5263668798 1.7315156631 1.4428514068 -1.2197352481 0.9144146579 1.0727263474 -0.1389358881 0.1092805780 0.7350208828 1.5293954595 0.0030278255 1.2472867347 -0.5258728625 1.3782633069 1.3495508831 -0.1403562064 0.2437382535 1.3804956588 0.8055826339 -0.0482092025 0.3327165165 -0.6311979224 0.7184578971 0.2491045282 1.4685857879 -0.8347049536 1.3670667538 -0.6855727502 1.6465021616 1.0593087096 0.0152957411 0.0638919221 0.9771215985 The result is   21.56503660... . Related task   Circles of given radius through two points. See also http://www.reddit.com/r/dailyprogrammer/comments/zff9o/9062012_challenge_96_difficult_water_droplets/ http://stackoverflow.com/a/1667789/10562
#XPL0
XPL0
real Circles, MinX, MaxX, MinY, MaxY, Temp, X, Y, DX, DY, Area; int N, Cnt1, Cnt2; def Del = 0.0005; def Inf = float(-1>>1); [\ X Y R Circles:= [ 1.6417233788, 1.6121789534, 0.0848270516, -1.4944608174, 1.2077959613, 1.1039549836, 0.6110294452, -0.6907087527, 0.9089162485, 0.3844862411, 0.2923344616, 0.2375743054, -0.2495892950, -0.3832854473, 1.0845181219, 1.7813504266, 1.6178237031, 0.8162655711, -0.1985249206, -0.8343333301, 0.0538864941, -1.7011985145, -0.1263820964, 0.4776976918, -0.4319462812, 1.4104420482, 0.7886291537, 0.2178372997, -0.9499557344, 0.0357871187, -0.6294854565, -1.3078893852, 0.7653357688, 1.7952608455, 0.6281269104, 0.2727652452, 1.4168575317, 1.0683357171, 1.1016025378, 1.4637371396, 0.9463877418, 1.1846214562, -0.5263668798, 1.7315156631, 1.4428514068, -1.2197352481, 0.9144146579, 1.0727263474, -0.1389358881, 0.1092805780, 0.7350208828, 1.5293954595, 0.0030278255, 1.2472867347, -0.5258728625, 1.3782633069, 1.3495508831, -0.1403562064, 0.2437382535, 1.3804956588, 0.8055826339, -0.0482092025, 0.3327165165, -0.6311979224, 0.7184578971, 0.2491045282, 1.4685857879, -0.8347049536, 1.3670667538, -0.6855727502, 1.6465021616, 1.0593087096, 0.0152957411, 0.0638919221, 0.9771215985]; MinX:= +Inf; MaxX:= -Inf; MinY:= +Inf; MaxY:= -Inf; for N:= 0 to 25*3-1 do [Temp:= Circles(N+0); if Temp < 0.0 then Temp:= Temp - Circles(N+2) else Temp:= Temp + Circles(N+2); if Temp < MinX then MinX:= Temp; if Temp > MaxX then MaxX:= Temp; Temp:= Circles(N+1); if Temp < 0.0 then Temp:= Temp - Circles(N+2) else Temp:= Temp + Circles(N+2); if Temp < MinY then MinY:= Temp; if Temp > MaxY then MaxY:= Temp; Circles(N+2):= sq(Circles(N+2)); \square for speed N:= N+2; ]; Cnt1:= 0; Cnt2:= 0; Y:= MinY; repeat X:= MinX; repeat loop [for N:= 0 to 25*3-1 do [DX:= X - Circles(N+0); DY:= Y - Circles(N+1); if DX*DX + DY*DY <= Circles(N+2) then [Cnt1:= Cnt1+1; quit]; N:= N+2; ]; quit; ]; Cnt2:= Cnt2+1; X:= X + Del; until X >= MaxX; Y:= Y + Del; until Y >= MaxY; Area:= (MaxX-MinX) * (MaxY-MinY); \of bounding box Area:= float(Cnt1)/float(Cnt2) * Area; \of circles RlOut(0, Area); ]
http://rosettacode.org/wiki/Topological_sort
Topological sort
Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort O(n2) sorts Bubble sort | Cocktail sort | Cocktail sort with shifting bounds | Comb sort | Cycle sort | Gnome sort | Insertion sort | Selection sort | Strand sort other sorts Bead sort | Bogo sort | Common sorted list | Composite structures sort | Custom comparator sort | Counting sort | Disjoint sublist sort | External sort | Jort sort | Lexicographical sort | Natural sorting | Order by pair comparisons | Order disjoint list items | Order two numerical lists | Object identifier (OID) sort | Pancake sort | Quickselect | Permutation sort | Radix sort | Ranking methods | Remove duplicate elements | Sleep sort | Stooge sort | [Sort letters of a string] | Three variable sort | Topological sort | Tree sort Given a mapping between items, and items they depend on, a topological sort orders items so that no item precedes an item it depends upon. The compiling of a library in the VHDL language has the constraint that a library must be compiled after any library it depends on. A tool exists that extracts library dependencies. Task Write a function that will return a valid compile order of VHDL libraries from their dependencies. Assume library names are single words. Items mentioned as only dependents, (sic), have no dependents of their own, but their order of compiling must be given. Any self dependencies should be ignored. Any un-orderable dependencies should be flagged. Use the following data as an example: LIBRARY LIBRARY DEPENDENCIES ======= ==================== des_system_lib std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee dw01 ieee dw01 dware gtech dw02 ieee dw02 dware dw03 std synopsys dware dw03 dw02 dw01 ieee gtech dw04 dw04 ieee dw01 dware gtech dw05 dw05 ieee dware dw06 dw06 ieee dware dw07 ieee dware dware ieee dware gtech ieee gtech ramlib std ieee std_cell_lib ieee std_cell_lib synopsys Note: the above data would be un-orderable if, for example, dw04 is added to the list of dependencies of dw01. C.f.   Topological sort/Extracted top item. There are two popular algorithms for topological sorting:   Kahn's 1962 topological sort [1]   depth-first search [2] [3]
#Huginn
Huginn
import Algorithms as algo; import Text as text;   class DirectedGraph { _adjecentVertices = {}; add_vertex( vertex_ ) { _adjecentVertices[vertex_] = []; } add_edge( from_, to_ ) { _adjecentVertices[from_].push( to_ ); } adjecent_vertices( vertex_ ) { return ( vertex_ ∈ _adjecentVertices ? _adjecentVertices.get( vertex_ ) : [] ); } }   class DepthFirstSearch { _visited = set(); _postOrder = []; _cycleDetector = set(); run( graph_, start_ ) { _cycleDetector.insert( start_ ); _visited.insert( start_ ); for ( vertex : graph_.adjecent_vertices( start_ ) ) { if ( vertex == start_ ) { continue; } if ( vertex ∈ _cycleDetector ) { throw Exception( "A cycle involving vertices {} found!".format( _cycleDetector ) ); } if ( vertex ∉ _visited ) { run( graph_, vertex ); } } _postOrder.push( start_ ); _cycleDetector.erase( start_ ); } topological_sort( graph_ ) { for ( vertex : graph_._adjecentVertices ) { if ( vertex ∉ _visited ) { run( graph_, vertex ); } } return ( _postOrder ); } }   main() { rawdata = "des_system_lib | std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee\n" "dw01 | ieee dw01 dware gtech\n" "dw02 | ieee dw02 dware\n" "dw03 | std synopsys dware dw03 dw02 dw01 ieee gtech\n" "dw04 | dw04 ieee dw01 dware gtech\n" "dw05 | dw05 ieee dware\n" "dw06 | dw06 ieee dware\n" "dw07 | ieee dware\n" "dware | ieee dware\n" "gtech | ieee gtech\n" "ramlib | std ieee\n" "std_cell_lib | ieee std_cell_lib\n" "synopsys |\n"; dg = DirectedGraph(); for ( l : algo.filter( text.split( rawdata, "\n" ), @( x ) { size( x ) > 0; } ) ) { def = algo.materialize( algo.map( text.split( l, "|" ), string.strip ), list ); dg.add_vertex( def[0] ); for ( n : algo.filter( algo.map( text.split( def[1], " " ), string.strip ), @( x ) { size( x ) > 0; } ) ) { dg.add_edge( def[0], n ); } } dfs = DepthFirstSearch(); print( "{}\n".format( dfs.topological_sort( dg ) ) ); }
http://rosettacode.org/wiki/Universal_Turing_machine
Universal Turing machine
One of the foundational mathematical constructs behind computer science is the universal Turing Machine. (Alan Turing introduced the idea of such a machine in 1936–1937.) Indeed one way to definitively prove that a language is turing-complete is to implement a universal Turing machine in it. Task Simulate such a machine capable of taking the definition of any other Turing machine and executing it. Of course, you will not have an infinite tape, but you should emulate this as much as is possible. The three permissible actions on the tape are "left", "right" and "stay". To test your universal Turing machine (and prove your programming language is Turing complete!), you should execute the following two Turing machines based on the following definitions. Simple incrementer States: q0, qf Initial state: q0 Terminating states: qf Permissible symbols: B, 1 Blank symbol: B Rules: (q0, 1, 1, right, q0) (q0, B, 1, stay, qf) The input for this machine should be a tape of 1 1 1 Three-state busy beaver States: a, b, c, halt Initial state: a Terminating states: halt Permissible symbols: 0, 1 Blank symbol: 0 Rules: (a, 0, 1, right, b) (a, 1, 1, left, c) (b, 0, 1, left, a) (b, 1, 1, right, b) (c, 0, 1, left, b) (c, 1, 1, stay, halt) The input for this machine should be an empty tape. Bonus: 5-state, 2-symbol probable Busy Beaver machine from Wikipedia States: A, B, C, D, E, H Initial state: A Terminating states: H Permissible symbols: 0, 1 Blank symbol: 0 Rules: (A, 0, 1, right, B) (A, 1, 1, left, C) (B, 0, 1, right, C) (B, 1, 1, right, B) (C, 0, 1, right, D) (C, 1, 0, left, E) (D, 0, 1, left, A) (D, 1, 1, left, D) (E, 0, 1, stay, H) (E, 1, 0, left, A) The input for this machine should be an empty tape. This machine runs for more than 47 millions steps.
#Nim
Nim
import strutils, tables   proc runUTM(state, halt, blank: string, tape: seq[string] = @[], rules: seq[seq[string]]) = var st = state pos = 0 tape = tape rulesTable: Table[tuple[s0, v0: string], tuple[v1, dr, s1: string]]   if tape.len == 0: tape = @[blank] if pos < 0: pos += tape.len assert pos in 0..tape.high   for r in rules: assert r.len == 5 rulesTable[(r[0], r[1])] = (r[2], r[3], r[4])   while true: stdout.write st, '\t' for i, v in tape: stdout.write if i == pos: '[' & v & ']' else: ' ' & v & ' ' echo()   if st == halt: break if not rulesTable.hasKey((st, tape[pos])): break   let (v1, dr, s1) = rulesTable[(st, tape[pos])] tape[pos] = v1 if dr == "left": if pos > 0: dec pos else: tape.insert blank if dr == "right": inc pos if pos >= tape.len: tape.add blank st = s1   echo "incr machine\n" runUTM(halt = "qf", state = "q0", tape = "1 1 1".split, blank = "B", rules = @["q0 1 1 right q0".splitWhitespace, "q0 B 1 stay qf".splitWhitespace])   echo "\nbusy beaver\n" runUTM(halt = "halt", state = "a", blank = "0", rules = @["a 0 1 right b".splitWhitespace, "a 1 1 left c".splitWhitespace, "b 0 1 left a".splitWhitespace, "b 1 1 right b".splitWhitespace, "c 0 1 left b".splitWhitespace, "c 1 1 stay halt".splitWhitespace])   echo "\nsorting test\n" runUTM(halt = "STOP", state = "A", blank = "0", tape = "2 2 2 1 2 2 1 2 1 2 1 2 1 2".split, rules = @["A 1 1 right A".splitWhitespace, "A 2 3 right B".splitWhitespace, "A 0 0 left E".splitWhitespace, "B 1 1 right B".splitWhitespace, "B 2 2 right B".splitWhitespace, "B 0 0 left C".splitWhitespace, "C 1 2 left D".splitWhitespace, "C 2 2 left C".splitWhitespace, "C 3 2 left E".splitWhitespace, "D 1 1 left D".splitWhitespace, "D 2 2 left D".splitWhitespace, "D 3 1 right A".splitWhitespace, "E 1 1 left E".splitWhitespace, "E 0 0 right STOP".splitWhitespace])
http://rosettacode.org/wiki/Totient_function
Totient function
The   totient   function is also known as:   Euler's totient function   Euler's phi totient function   phi totient function   Φ   function   (uppercase Greek phi)   φ    function   (lowercase Greek phi) Definitions   (as per number theory) The totient function:   counts the integers up to a given positive integer   n   that are relatively prime to   n   counts the integers   k   in the range   1 ≤ k ≤ n   for which the greatest common divisor   gcd(n,k)   is equal to   1   counts numbers   ≤ n   and   prime to   n If the totient number   (for N)   is one less than   N,   then   N   is prime. Task Create a   totient   function and:   Find and display   (1 per line)   for the 1st   25   integers:   the integer   (the index)   the totient number for that integer   indicate if that integer is prime   Find and display the   count   of the primes up to          100   Find and display the   count   of the primes up to       1,000   Find and display the   count   of the primes up to     10,000   Find and display the   count   of the primes up to   100,000     (optional) Show all output here. Related task   Perfect totient numbers Also see   Wikipedia: Euler's totient function.   MathWorld: totient function.   OEIS: Euler totient function phi(n).
#Pascal
Pascal
{$IFDEF FPC} {$MODE DELPHI} {$IFEND} function gcd_mod(u, v: NativeUint): NativeUint;inline; //prerequisites u > v and u,v > 0 var t: NativeUInt; begin repeat t := u; u := v; v := t mod v; until v = 0; gcd_mod := u; end;   function Totient(n:NativeUint):NativeUint; var i : NativeUint; Begin result := 1; For i := 2 to n do inc(result,ORD(GCD_mod(n,i)=1)); end;   function CheckPrimeTotient(n:NativeUint):Boolean;inline; begin result := (Totient(n) = (n-1)); end;   procedure OutCountPrimes(n:NativeUInt); var i,cnt : NativeUint; begin cnt := 0; For i := 1 to n do inc(cnt,Ord(CheckPrimeTotient(i))); writeln(n:10,cnt:8); end;   procedure display(n:NativeUint); var idx,phi : NativeUint; Begin if n = 0 then EXIT; writeln('number n':5,'Totient(n)':11,'isprime':8); For idx := 1 to n do Begin phi := Totient(idx); writeln(idx:4,phi:10,(phi=(idx-1)):12); end end; var i : NativeUint; Begin display(25);   writeln('Limit primecount'); i := 100; repeat OutCountPrimes(i); i := i*10; until i >100000; end.
http://rosettacode.org/wiki/Topswops
Topswops
Topswops is a card game created by John Conway in the 1970's. Assume you have a particular permutation of a set of   n   cards numbered   1..n   on both of their faces, for example the arrangement of four cards given by   [2, 4, 1, 3]   where the leftmost card is on top. A round is composed of reversing the first   m   cards where   m   is the value of the topmost card. Rounds are repeated until the topmost card is the number   1   and the number of swaps is recorded. For our example the swaps produce: [2, 4, 1, 3] # Initial shuffle [4, 2, 1, 3] [3, 1, 2, 4] [2, 1, 3, 4] [1, 2, 3, 4] For a total of four swaps from the initial ordering to produce the terminating case where   1   is on top. For a particular number   n   of cards,   topswops(n)   is the maximum swaps needed for any starting permutation of the   n   cards. Task The task is to generate and show here a table of   n   vs   topswops(n)   for   n   in the range   1..10   inclusive. Note Topswops   is also known as   Fannkuch   from the German word   Pfannkuchen   meaning   pancake. Related tasks   Number reversal game   Sorting algorithms/Pancake sort
#Wren
Wren
import "/fmt" for Fmt   var maxn = 10 var maxl = 50   var steps = Fn.new { |n| var a = List.filled(maxl, null) var b = List.filled(maxl, null) var x = List.filled(maxl, 0) for (i in 0...maxl) { a[i] = List.filled(maxn + 1, 0) b[i] = List.filled(maxn + 1, 0) } a[0][0] = 1 var m = 0 var l = 0 while (true) { x[l] = x[l] + 1 var k = x[l] var cont = false if (k >= n) { if (l <= 0) break l = l - 1 cont = true } else if (a[l][k] == 0) { if (b[l][k+1] != 0) cont = true } else if (a[l][k] != k + 1) { cont = true } if (!cont) { a[l+1] = a[l].toList var j = 1 while (j <= k) { a[l+1][j] = a[l][k-j] j = j + 1 } b[l+1] = b[l].toList a[l+1][0] = k + 1 b[l+1][k+1] = 1 if (l > m - 1) { m = l + 1 } l = l + 1 x[l] = 0 } } return m }   for (i in 1..maxn) Fmt.print("$2d: $d", i, steps.call(i))
http://rosettacode.org/wiki/Trigonometric_functions
Trigonometric functions
Task If your language has a library or built-in functions for trigonometry, show examples of:   sine   cosine   tangent   inverses   (of the above) using the same angle in radians and degrees. For the non-inverse functions,   each radian/degree pair should use arguments that evaluate to the same angle   (that is, it's not necessary to use the same angle for all three regular functions as long as the two sine calls use the same angle). For the inverse functions,   use the same number and convert its answer to radians and degrees. If your language does not have trigonometric functions available or only has some available,   write functions to calculate the functions based on any   known approximation or identity.
#Go
Go
package main   import ( "fmt" "math" )   const d = 30. const r = d * math.Pi / 180   var s = .5 var c = math.Sqrt(3) / 2 var t = 1 / math.Sqrt(3)   func main() { fmt.Printf("sin(%9.6f deg) = %f\n", d, math.Sin(d*math.Pi/180)) fmt.Printf("sin(%9.6f rad) = %f\n", r, math.Sin(r)) fmt.Printf("cos(%9.6f deg) = %f\n", d, math.Cos(d*math.Pi/180)) fmt.Printf("cos(%9.6f rad) = %f\n", r, math.Cos(r)) fmt.Printf("tan(%9.6f deg) = %f\n", d, math.Tan(d*math.Pi/180)) fmt.Printf("tan(%9.6f rad) = %f\n", r, math.Tan(r)) fmt.Printf("asin(%f) = %9.6f deg\n", s, math.Asin(s)*180/math.Pi) fmt.Printf("asin(%f) = %9.6f rad\n", s, math.Asin(s)) fmt.Printf("acos(%f) = %9.6f deg\n", c, math.Acos(c)*180/math.Pi) fmt.Printf("acos(%f) = %9.6f rad\n", c, math.Acos(c)) fmt.Printf("atan(%f) = %9.6f deg\n", t, math.Atan(t)*180/math.Pi) fmt.Printf("atan(%f) = %9.6f rad\n", t, math.Atan(t)) }
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#PureBasic
PureBasic
Procedure.d f(x.d) ProcedureReturn Pow(Abs(x), 0.5) + 5 * x * x * x EndProcedure   Procedure split(i.s, delimeter.s, List o.d()) Protected index = CountString(i, delimeter) + 1 ;add 1 because last entry will not have a delimeter   While index > 0 AddElement(o()) o() = ValD(Trim(StringField(i, index, delimeter))) index - 1 Wend   ProcedureReturn ListSize(o()) EndProcedure   Define i$, entriesAreValid = 0, result.d, output$ NewList numbers.d()   If OpenConsole() Repeat PrintN(#crlf$ + "Enter eleven numbers that are each separated by spaces or commas:")   i$ = Input( i$ = Trim(i$) If split(i$, ",", numbers.d()) < 11 ClearList(numbers()) If split(i$, " ", numbers.d()) < 11 PrintN("Not enough numbers were supplied.") ClearList(numbers()) Else entriesAreValid = 1 EndIf Else entriesAreValid = 1 EndIf Until entriesAreValid = 1   ForEach numbers() output$ = "f(" + RTrim(RTrim(StrD(numbers(), 3), "0"), ".") + ") = " result.d = f(numbers()) If result > 400 output$ + "Too Large" Else output$ + RTrim(RTrim(StrD(result, 3), "0"), ".") EndIf PrintN(output$) Next   Print(#crlf$ + #crlf$ + "Press ENTER to exit"): Input() CloseConsole() EndIf
http://rosettacode.org/wiki/Truncatable_primes
Truncatable primes
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 739, 73, and 7 formed by removing digits from its right are also prime. No zeroes are allowed in truncatable primes. Task The task is to find the largest left-truncatable and right-truncatable primes less than one million (base 10 is implied). Related tasks Find largest left truncatable prime in a given base Sieve of Eratosthenes See also Truncatable Prime from MathWorld.]
#Prolog
Prolog
largest_left_truncatable_prime(N, N):- is_left_truncatable_prime(N), !. largest_left_truncatable_prime(N, P):- N > 1, N1 is N - 1, largest_left_truncatable_prime(N1, P).   is_left_truncatable_prime(P):- is_prime(P), is_left_truncatable_prime(P, P, 10).   is_left_truncatable_prime(P, _, N):- P =< N, !. is_left_truncatable_prime(P, Q, N):- Q1 is P mod N, is_prime(Q1), Q \= Q1, N1 is N * 10, is_left_truncatable_prime(P, Q1, N1).   largest_right_truncatable_prime(N, N):- is_right_truncatable_prime(N), !. largest_right_truncatable_prime(N, P):- N > 1, N1 is N - 1, largest_right_truncatable_prime(N1, P).   is_right_truncatable_prime(P):- is_prime(P), Q is P // 10, (Q == 0, ! ; is_right_truncatable_prime(Q)).   main(N):- find_prime_numbers(N), largest_left_truncatable_prime(N, L), writef('Largest left-truncatable prime less than %t: %t\n', [N, L]), largest_right_truncatable_prime(N, R), writef('Largest right-truncatable prime less than %t: %t\n', [N, R]).   main:- main(1000000).
http://rosettacode.org/wiki/Tree_traversal
Tree traversal
Task Implement a binary tree where each node carries an integer,   and implement:   pre-order,   in-order,   post-order,     and   level-order   traversal. Use those traversals to output the following tree: 1 / \ / \ / \ 2 3 / \ / 4 5 6 / / \ 7 8 9 The correct output should look like this: preorder: 1 2 4 7 5 3 6 8 9 inorder: 7 4 2 5 1 8 6 9 3 postorder: 7 4 5 2 8 9 6 3 1 level-order: 1 2 3 4 5 6 7 8 9 See also   Wikipedia article:   Tree traversal.
#Eiffel
Eiffel
note description : "Application for tree traversal demonstration" output : "[ Prints preorder, inorder, postorder and levelorder traversal of an example binary tree. ]" author : "Jascha Grübel" date : "$2014-01-07$" revision : "$1.0$"   class APPLICATION   create make   feature {NONE} -- Initialization   make -- Run Tree traversal example. local tree:NODE do create tree.make (1) tree.set_left_child (create {NODE}.make (2)) tree.set_right_child (create {NODE}.make (3)) tree.left_child.set_left_child (create {NODE}.make (4)) tree.left_child.set_right_child (create {NODE}.make (5)) tree.left_child.left_child.set_left_child (create {NODE}.make (7)) tree.right_child.set_left_child (create {NODE}.make (6)) tree.right_child.left_child.set_left_child (create {NODE}.make (8)) tree.right_child.left_child.set_right_child (create {NODE}.make (9))   Io.put_string ("preorder: ") tree.print_preorder Io.put_new_line   Io.put_string ("inorder: ") tree.print_inorder Io.put_new_line   Io.put_string ("postorder: ") tree.print_postorder Io.put_new_line   Io.put_string ("level-order:") tree.print_levelorder Io.put_new_line   end   end -- class APPLICATION
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Clojure
Clojure
(apply str (interpose "." (.split #"," "Hello,How,Are,You,Today")))
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#CLU
CLU
% This iterator splits the string on a given character, % and returns each substring in order. tokenize = iter (s: string, c: char) yields (string) while ~string$empty(s) do next: int := string$indexc(c, s) if next = 0 then yield(s) break else yield(string$substr(s, 1, next-1)) s := string$rest(s, next+1) end end end tokenize   start_up = proc () po: stream := stream$primary_output() str: string := "Hello,How,Are,You,Today"   for part: string in tokenize(str, ',') do stream$putl(po, part || ".") end end start_up
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#C.23
C#
using System; using System.Linq; using System.Threading; using System.Diagnostics;   class Program { static void Main(string[] args) { Stopwatch sw = new Stopwatch();   sw.Start(); DoSomething(); sw.Stop();   Console.WriteLine("DoSomething() took {0}ms.", sw.Elapsed.TotalMilliseconds); }   static void DoSomething() { Thread.Sleep(1000);   Enumerable.Range(1, 10000).Where(x => x % 2 == 0).Sum(); // Sum even numers from 1 to 10000 } }
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#C.2B.2B
C++
#include <ctime> #include <iostream> using namespace std;   int identity(int x) { return x; } int sum(int num) { for (int i = 0; i < 1000000; i++) num += i; return num; }   double time_it(int (*action)(int), int arg) { clock_t start_time = clock(); action(arg); clock_t finis_time = clock(); return ((double) (finis_time - start_time)) / CLOCKS_PER_SEC; }   int main() { cout << "Identity(4) takes " << time_it(identity, 4) << " seconds." << endl; cout << "Sum(4) takes " << time_it(sum, 4) << " seconds." << endl; return 0; }
http://rosettacode.org/wiki/Top_rank_per_group
Top rank per group
Task Find the top   N   salaries in each department,   where   N   is provided as a parameter. Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source: Employee Name,Employee ID,Salary,Department Tyler Bennett,E10297,32000,D101 John Rappl,E21437,47000,D050 George Woltman,E00127,53500,D101 Adam Smith,E63535,18000,D202 Claire Buckman,E39876,27800,D202 David McClellan,E04242,41500,D101 Rich Holcomb,E01234,49500,D202 Nathan Adams,E41298,21900,D050 Richard Potter,E43128,15900,D101 David Motsinger,E27002,19250,D202 Tim Sampair,E03033,27000,D101 Kim Arlich,E10001,57000,D190 Timothy Grove,E16398,29900,D190
#EchoLisp
EchoLisp
  (lib 'struct) ;; tables are based upon structures (lib 'sql) ;; sql-select function   ;; input table (define emps (make-table (struct emp (name id salary dept)))) ;; output table (define high (make-table (struct out (dept name salary))))   ;; sort/group procedure (define (get-high num-records: N into: high) (sql-select emp.dept emp.name emp.salary from emps group-by emp.dept order-by emp.salary desc limit N into high))  
http://rosettacode.org/wiki/Tic-tac-toe
Tic-tac-toe
Task Play a game of tic-tac-toe. Ensure that legal moves are played and that a winning position is notified. Tic-tac-toe   is also known as:   naughts and crosses   tic tac toe   tick tack toe   three in a row   tres en rayo       and   Xs  and  Os See also   MathWorld™, Tic-Tac-Toe game.   Wikipedia tic-tac-toe.
#Befunge
Befunge
v123456789 --- >9 >48*,:55+\-0g,1v >9>066+0p076+0p^ ^,," |"_v#%3:- < :,,0537051v>:#,_$#^5#,5#+<>:#v_55+ 74 1098709<^+55"---+---+---"0<v520 69 04560123 >:!#v_0\1v>$2-:6%v>803 6 +0g\66++0p^ $_>#% v#9:-1_ 6/5 5 vv5!/*88\%*28 ::g0_^>9/#v_ "I", ,,5v>5++0p82*/3-:*+\:^v,_@ >"uoY", 0+5<v0+66_v#!%2:_55v >:^:" win!"\ 1-^ g >$>0" :evom ruoY">:#,_$v>p \*8+ 65_^#!/*88g0** `0\!`9:::<&<^0 v >:!67+0g:!56+0g *+*+0" :evom " >"yM">:#,_$ :. 1234+++, 789*+ \0^< "a s't"98:*+>:#,_$@>365*+"ward"48*  
http://rosettacode.org/wiki/Towers_of_Hanoi
Towers of Hanoi
Task Solve the   Towers of Hanoi   problem with recursion.
#BCPL
BCPL
get "libhdr"   let start() be move(4, 1, 2, 3) and move(n, src, via, dest) be if n > 0 do $( move(n-1, src, dest, via) writef("Move disk from pole %N to pole %N*N", src, dest); move(n-1, via, src, dest) $)
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#jq
jq
def thueMorse: 0, ({sb0: "0", sb1: "1", n:1 } | while( true; {n: (.sb0|length), sb0: (.sb0 + .sb1), sb1: (.sb1 + .sb0)} ) | .sb0[.n:] | explode[] | . - 48);
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#Julia
Julia
function thuemorse(len::Int) rst = Vector{Int8}(len) rst[1] = 0 i, imax = 2, 1 while i ≤ len while i ≤ len && i ≤ 2 * imax rst[i] = 1 - rst[i-imax] i += 1 end imax *= 2 end return rst end   println(join(thuemorse(100)))
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#Kotlin
Kotlin
fun thueMorse(n: Int): String { val sb0 = StringBuilder("0") val sb1 = StringBuilder("1") repeat(n) { val tmp = sb0.toString() sb0.append(sb1) sb1.append(tmp) } return sb0.toString() }   fun main() { for (i in 0..6) println("$i : ${thueMorse(i)}") }
http://rosettacode.org/wiki/Tonelli-Shanks_algorithm
Tonelli-Shanks algorithm
This page uses content from Wikipedia. The original article was at Tonelli-Shanks algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In computational number theory, the Tonelli–Shanks algorithm is a technique for solving for x in a congruence of the form: x2 ≡ n (mod p) where n is an integer which is a quadratic residue (mod p), p is an odd prime, and x,n ∈ Fp where Fp = {0, 1, ..., p - 1}. It is used in cryptography techniques. To apply the algorithm, we need the Legendre symbol: The Legendre symbol (a | p) denotes the value of a(p-1)/2 (mod p). (a | p) ≡ 1    if a is a square (mod p) (a | p) ≡ -1    if a is not a square (mod p) (a | p) ≡ 0    if a ≡ 0 (mod p) Algorithm pseudo-code All ≡ are taken to mean (mod p) unless stated otherwise. Input: p an odd prime, and an integer n . Step 0: Check that n is indeed a square: (n | p) must be ≡ 1 . Step 1: By factoring out powers of 2 from p - 1, find q and s such that p - 1 = q2s with q odd . If p ≡ 3 (mod 4) (i.e. s = 1), output the two solutions r ≡ ± n(p+1)/4 . Step 2: Select a non-square z such that (z | p) ≡ -1 and set c ≡ zq . Step 3: Set r ≡ n(q+1)/2, t ≡ nq, m = s . Step 4: Loop the following: If t ≡ 1, output r and p - r . Otherwise find, by repeated squaring, the lowest i, 0 < i < m , such that t2i ≡ 1 . Let b ≡ c2(m - i - 1), and set r ≡ rb, t ≡ tb2, c ≡ b2 and m = i . Task Implement the above algorithm. Find solutions (if any) for n = 10 p = 13 n = 56 p = 101 n = 1030 p = 10009 n = 1032 p = 10009 n = 44402 p = 100049 Extra credit n = 665820697 p = 1000000009 n = 881398088036 p = 1000000000039 n = 41660815127637347468140745042827704103445750172002 p = 10^50 + 577 See also Modular exponentiation Cipolla's algorithm
#Visual_Basic_.NET
Visual Basic .NET
Imports System.Numerics   Module Module1   Class Solution ReadOnly root1 As BigInteger ReadOnly root2 As BigInteger ReadOnly exists As Boolean   Sub New(r1 As BigInteger, r2 As BigInteger, e As Boolean) root1 = r1 root2 = r2 exists = e End Sub   Public Function GetRoot1() As BigInteger Return root1 End Function   Public Function GetRoot2() As BigInteger Return root2 End Function   Public Function GetExists() As Boolean Return exists End Function End Class   Function Ts(n As BigInteger, p As BigInteger) As Solution If BigInteger.ModPow(n, (p - 1) / 2, p) <> 1 Then Return New Solution(0, 0, False) End If   Dim q As BigInteger = p - 1 Dim ss = BigInteger.Zero While (q Mod 2) = 0 ss += 1 q >>= 1 End While   If ss = 1 Then Dim r1 = BigInteger.ModPow(n, (p + 1) / 4, p) Return New Solution(r1, p - r1, True) End If   Dim z As BigInteger = 2 While BigInteger.ModPow(z, (p - 1) / 2, p) <> p - 1 z += 1 End While Dim c = BigInteger.ModPow(z, q, p) Dim r = BigInteger.ModPow(n, (q + 1) / 2, p) Dim t = BigInteger.ModPow(n, q, p) Dim m = ss   Do If t = 1 Then Return New Solution(r, p - r, True) End If Dim i = BigInteger.Zero Dim zz = t While zz <> 1 AndAlso i < (m - 1) zz = zz * zz Mod p i += 1 End While Dim b = c Dim e = m - i - 1 While e > 0 b = b * b Mod p e = e - 1 End While r = r * b Mod p c = b * b Mod p t = t * c Mod p m = i Loop End Function   Sub Main() Dim pairs = New List(Of Tuple(Of Long, Long)) From { New Tuple(Of Long, Long)(10, 13), New Tuple(Of Long, Long)(56, 101), New Tuple(Of Long, Long)(1030, 10009), New Tuple(Of Long, Long)(1032, 10009), New Tuple(Of Long, Long)(44402, 100049), New Tuple(Of Long, Long)(665820697, 1000000009), New Tuple(Of Long, Long)(881398088036, 1000000000039) }   For Each pair In pairs Dim sol = Ts(pair.Item1, pair.Item2) Console.WriteLine("n = {0}", pair.Item1) Console.WriteLine("p = {0}", pair.Item2) If sol.GetExists() Then Console.WriteLine("root1 = {0}", sol.GetRoot1()) Console.WriteLine("root2 = {0}", sol.GetRoot2()) Else Console.WriteLine("No solution exists") End If Console.WriteLine() Next   Dim bn = BigInteger.Parse("41660815127637347468140745042827704103445750172002") Dim bp = BigInteger.Pow(10, 50) + 577 Dim bsol = Ts(bn, bp) Console.WriteLine("n = {0}", bn) Console.WriteLine("p = {0}", bp) If bsol.GetExists() Then Console.WriteLine("root1 = {0}", bsol.GetRoot1()) Console.WriteLine("root2 = {0}", bsol.GetRoot2()) Else Console.WriteLine("No solution exists") End If End Sub   End Module
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Kotlin
Kotlin
// version 1.1.3   const val SPE = "\ufffe" // unused unicode char in Specials block const val SPF = "\uffff" // ditto   fun tokenize(str: String, sep: Char, esc: Char): List<String> { var s = str.replace("$esc$esc", SPE).replace("$esc$sep", SPF) s = if (s.last() == esc) // i.e. 'esc' not escaping anything s.dropLast(1).replace("$esc", "") + esc else s.replace("$esc", "") return s.split(sep).map { it.replace(SPE, "$esc").replace(SPF, "$sep") } }   fun main(args: Array<String>) { var str = "one^|uno||three^^^^|four^^^|^cuatro|" val sep = '|' val esc = '^' val items = tokenize(str, sep, esc) for (item in items) println(if (item.isEmpty()) "(empty)" else item) }
http://rosettacode.org/wiki/Total_circles_area
Total circles area
Total circles area You are encouraged to solve this task according to the task description, using any language you may know. Example circles Example circles filtered Given some partially overlapping circles on the plane, compute and show the total area covered by them, with four or six (or a little more) decimal digits of precision. The area covered by two or more disks needs to be counted only once. One point of this Task is also to compare and discuss the relative merits of various solution strategies, their performance, precision and simplicity. This means keeping both slower and faster solutions for a language (like C) is welcome. To allow a better comparison of the different implementations, solve the problem with this standard dataset, each line contains the x and y coordinates of the centers of the disks and their radii   (11 disks are fully contained inside other disks): xc yc radius 1.6417233788 1.6121789534 0.0848270516 -1.4944608174 1.2077959613 1.1039549836 0.6110294452 -0.6907087527 0.9089162485 0.3844862411 0.2923344616 0.2375743054 -0.2495892950 -0.3832854473 1.0845181219 1.7813504266 1.6178237031 0.8162655711 -0.1985249206 -0.8343333301 0.0538864941 -1.7011985145 -0.1263820964 0.4776976918 -0.4319462812 1.4104420482 0.7886291537 0.2178372997 -0.9499557344 0.0357871187 -0.6294854565 -1.3078893852 0.7653357688 1.7952608455 0.6281269104 0.2727652452 1.4168575317 1.0683357171 1.1016025378 1.4637371396 0.9463877418 1.1846214562 -0.5263668798 1.7315156631 1.4428514068 -1.2197352481 0.9144146579 1.0727263474 -0.1389358881 0.1092805780 0.7350208828 1.5293954595 0.0030278255 1.2472867347 -0.5258728625 1.3782633069 1.3495508831 -0.1403562064 0.2437382535 1.3804956588 0.8055826339 -0.0482092025 0.3327165165 -0.6311979224 0.7184578971 0.2491045282 1.4685857879 -0.8347049536 1.3670667538 -0.6855727502 1.6465021616 1.0593087096 0.0152957411 0.0638919221 0.9771215985 The result is   21.56503660... . Related task   Circles of given radius through two points. See also http://www.reddit.com/r/dailyprogrammer/comments/zff9o/9062012_challenge_96_difficult_water_droplets/ http://stackoverflow.com/a/1667789/10562
#zkl
zkl
circles:=File("circles.txt").pump(List,'wrap(line){ line.split().apply("toFloat") // L(x,y,r) }); # compute the bounding box of the circles x_min:=(0.0).min(circles.apply(fcn([(x,y,r)]){ x - r })); // (0) not used, just the list of numbers x_max:=(0.0).max(circles.apply(fcn([(x,y,r)]){ x + r })); y_min:=(0.0).min(circles.apply(fcn([(x,y,r)]){ y - r })); y_max:=(0.0).max(circles.apply(fcn([(x,y,r)]){ y + r }));   box_side:=500; dx:=(x_max - x_min)/box_side; dy:=(y_max - y_min)/box_side;   count:=0; foreach r in (box_side){ y:=y_min + dy*r; foreach c in (box_side){ x:=x_min + dx*c; count+=circles.filter1('wrap([(cx,cy,cr)]){ x-=cx; y-=cy; x*x + y*y <= cr*cr }).toBool(); // -->False|L(x,y,z), L(x,y,r).toBool()-->True, } }   println("Approximated area: ", dx*dy*count);
http://rosettacode.org/wiki/Topological_sort
Topological sort
Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort O(n2) sorts Bubble sort | Cocktail sort | Cocktail sort with shifting bounds | Comb sort | Cycle sort | Gnome sort | Insertion sort | Selection sort | Strand sort other sorts Bead sort | Bogo sort | Common sorted list | Composite structures sort | Custom comparator sort | Counting sort | Disjoint sublist sort | External sort | Jort sort | Lexicographical sort | Natural sorting | Order by pair comparisons | Order disjoint list items | Order two numerical lists | Object identifier (OID) sort | Pancake sort | Quickselect | Permutation sort | Radix sort | Ranking methods | Remove duplicate elements | Sleep sort | Stooge sort | [Sort letters of a string] | Three variable sort | Topological sort | Tree sort Given a mapping between items, and items they depend on, a topological sort orders items so that no item precedes an item it depends upon. The compiling of a library in the VHDL language has the constraint that a library must be compiled after any library it depends on. A tool exists that extracts library dependencies. Task Write a function that will return a valid compile order of VHDL libraries from their dependencies. Assume library names are single words. Items mentioned as only dependents, (sic), have no dependents of their own, but their order of compiling must be given. Any self dependencies should be ignored. Any un-orderable dependencies should be flagged. Use the following data as an example: LIBRARY LIBRARY DEPENDENCIES ======= ==================== des_system_lib std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee dw01 ieee dw01 dware gtech dw02 ieee dw02 dware dw03 std synopsys dware dw03 dw02 dw01 ieee gtech dw04 dw04 ieee dw01 dware gtech dw05 dw05 ieee dware dw06 dw06 ieee dware dw07 ieee dware dware ieee dware gtech ieee gtech ramlib std ieee std_cell_lib ieee std_cell_lib synopsys Note: the above data would be un-orderable if, for example, dw04 is added to the list of dependencies of dw01. C.f.   Topological sort/Extracted top item. There are two popular algorithms for topological sorting:   Kahn's 1962 topological sort [1]   depth-first search [2] [3]
#Icon_and_Unicon
Icon and Unicon
record graph(nodes,arcs) global ex_name, in_name   procedure main() show(tsort(getgraph())) end   procedure tsort(g) t := "" while (n := g.nodes -- pnodes(g)) ~== "" do { t ||:= "("||n||")" g := delete(g,n) } if g.nodes == '' then return t write("graph contains the cycle:") write("\t",genpath(fn := !g.nodes,fn,g)) end   ## pnodes(g) -- return the predecessor nodes of g # (those that have an arc from them) procedure pnodes(g) static labels, fromnodes initial { labels := &ucase fromnodes := 'ACEGIKMOQSUWY' } return cset(select(g.arcs,labels, fromnodes)) end   ## select(s,image,object) - efficient node selection procedure select(s,image,object) slen := *s ilen := *image return if slen <= ilen then map(object[1+:slen/2],image[1+:slen],s) else map(object,image,s[1+:ilen]) || select(s[1+ilen:0],image,object) end   ## delete(g,x) -- deletes all nodes in x from graph g # note that arcs must be deleted as well procedure delete(g,x) t := "" g.arcs ? while arc := move(2) do if not upto(x,arc) then t ||:= arc return graph(g.nodes--x,t) end     ## getgraph() -- read and construct a graph # graph is described via sets of arcs, as in: # # from to1 to2 to3 # # external names are converted to single character names for efficiency # self-referential arcs are ignored procedure getgraph() static labels initial labels := &cset ex_name := table() in_name := table() count := 0 arcstr := "" nodes := '' every line := !&input do { nextWord := create genWords(line) if nfrom := @nextWord then { /in_name[nfrom] := &cset[count +:= 1] /ex_name[in_name[nfrom]] := nfrom nodes ++:= in_name[nfrom] while nto := @nextWord do { if nfrom ~== nto then { /in_name[nto] := &cset[count +:= 1] /ex_name[in_name[nto]] := nto nodes ++:= in_name[nto] arcstr ||:= in_name[nfrom] || in_name[nto] } } } } return graph(nodes,arcstr) end   # generate all 'words' in string procedure genWords(s) static wchars initial wchars := &cset -- ' \t' s ? while tab(upto(wchars))\1 do suspend tab(many(wchars))\1 end   ## show(t) - return the external names (in order) for the nodes in t # Each output line contains names that are independent of each other procedure show(t) line := "" every n := !t do case n of { "(" : line ||:= "\n\t(" ")" : line[-1] := ")" default : line ||:= ex_name[n] || " " } write(line) end   ## genpath(f,t,g) -- generate paths from f to t in g procedure genpath(f,t,g, seen) /seen := '' seen ++:= f sn := nnodes(f,g) if t ** sn == t then return ex_name[f] || " -> " || ex_name[t] suspend ex_name[f] || " -> " || genpath(!(sn --seen),t,g,seen) end   ## nnodes(f,g) -- compute all nodes that could follow f in g procedure nnodes(f,g) t := '' g.arcs ? while arc := move(2) do if arc[1] == f then t ++:= arc[2] return t end
http://rosettacode.org/wiki/Universal_Turing_machine
Universal Turing machine
One of the foundational mathematical constructs behind computer science is the universal Turing Machine. (Alan Turing introduced the idea of such a machine in 1936–1937.) Indeed one way to definitively prove that a language is turing-complete is to implement a universal Turing machine in it. Task Simulate such a machine capable of taking the definition of any other Turing machine and executing it. Of course, you will not have an infinite tape, but you should emulate this as much as is possible. The three permissible actions on the tape are "left", "right" and "stay". To test your universal Turing machine (and prove your programming language is Turing complete!), you should execute the following two Turing machines based on the following definitions. Simple incrementer States: q0, qf Initial state: q0 Terminating states: qf Permissible symbols: B, 1 Blank symbol: B Rules: (q0, 1, 1, right, q0) (q0, B, 1, stay, qf) The input for this machine should be a tape of 1 1 1 Three-state busy beaver States: a, b, c, halt Initial state: a Terminating states: halt Permissible symbols: 0, 1 Blank symbol: 0 Rules: (a, 0, 1, right, b) (a, 1, 1, left, c) (b, 0, 1, left, a) (b, 1, 1, right, b) (c, 0, 1, left, b) (c, 1, 1, stay, halt) The input for this machine should be an empty tape. Bonus: 5-state, 2-symbol probable Busy Beaver machine from Wikipedia States: A, B, C, D, E, H Initial state: A Terminating states: H Permissible symbols: 0, 1 Blank symbol: 0 Rules: (A, 0, 1, right, B) (A, 1, 1, left, C) (B, 0, 1, right, C) (B, 1, 1, right, B) (C, 0, 1, right, D) (C, 1, 0, left, E) (D, 0, 1, left, A) (D, 1, 1, left, D) (E, 0, 1, stay, H) (E, 1, 0, left, A) The input for this machine should be an empty tape. This machine runs for more than 47 millions steps.
#Pascal
Pascal
program project1; uses Classes, sysutils; type TCurrent = record state : string; input : char; end; TMovesTo = record state : string; output : char; moves : char; end; var ST, ET: TDateTime; C:TCurrent; M:TMovesTo; Tape, Rules:TStringList; TP:integer; //TP = Tape position Blank : char; j:integer; FinalState, InitialState, R : string; Count:integer; Function ApplyRule(C:TCurrent):TMovesTo; var x,k:integer; begin //Find the appropriate rule and pass it as the result For k:= 0 to Rules.Count-1 do begin If (k mod 5 = 0) and (Rules[k] = C.state) and (Rules[k+1] = C.input) then begin Result.output := Rules[k+2][1]; Result.moves := Rules[k+3][1]; Result.state := Rules[k+4]; end; end; end; Procedure ChangeTape(var TapePosition:integer;N:TMovesTo); begin Tape[TapePosition]:=N.output; Case N.moves of 'l':begin TapePosition := TapePosition-1; end; 'r':begin TapePosition := TapePosition+1; end; end; end; function GetInput(TapePosition:integer):char; begin Result:=Tape[TapePosition][1]; end; procedure ShowResult; var k:integer; begin writeln('Current State  :',C.state); writeln('Input  :',C.input); write(' Tape '); For k:= 0 to Tape.count-1 do begin write(Tape[k]); end; writeln; writeln('New State  :',M.state); writeln('Tape position :',TP); writeln('-----------------------'); end; begin writeln('Universal Turing Machine'); writeln('------------------------'); Count:=0; ST:=Time; //Set up the rules Rules := TStringList.create; R := 'q0,1,1,right,q0,q0,B,1,stay,qf'; Rules.CommaText := R; InitialState := 'q0'; FinalState := 'qf'; //Set up the tape Tape:=TStringList.create; Tape.add('1'); Tape.add('1'); Tape.add('1'); Blank := 'B'; For j:= 1 to 10 do begin Tape.add(Blank); end; //Set up the initial state writeln('Initial state'); C.state:=InitialState; C.input:=' '; M.state:=''; M.output:=' '; M.moves:=' '; TP:=0; //Run the machine While (TP >= 0) and (M.State <> FinalState) do begin C.Input := GetInput(TP); If M.state <> '' then begin C.State := M.State; end; M:=ApplyRule(C); ChangeTape(TP,M); Count:=Count+1; ShowResult; end; //State the outcome. If TP < 0 then begin writeln('Error! Tape has slipped off at left!'); end; If M.state = FinalState then begin writeln('Program has finished'); ET:=Time; writeln('Time taken '); writeln(FormatDateTime('sss:zzz',ET-ST)); writeln(Count, ' steps taken'); end; Tape.free; Rules.free; readln; end.
http://rosettacode.org/wiki/Totient_function
Totient function
The   totient   function is also known as:   Euler's totient function   Euler's phi totient function   phi totient function   Φ   function   (uppercase Greek phi)   φ    function   (lowercase Greek phi) Definitions   (as per number theory) The totient function:   counts the integers up to a given positive integer   n   that are relatively prime to   n   counts the integers   k   in the range   1 ≤ k ≤ n   for which the greatest common divisor   gcd(n,k)   is equal to   1   counts numbers   ≤ n   and   prime to   n If the totient number   (for N)   is one less than   N,   then   N   is prime. Task Create a   totient   function and:   Find and display   (1 per line)   for the 1st   25   integers:   the integer   (the index)   the totient number for that integer   indicate if that integer is prime   Find and display the   count   of the primes up to          100   Find and display the   count   of the primes up to       1,000   Find and display the   count   of the primes up to     10,000   Find and display the   count   of the primes up to   100,000     (optional) Show all output here. Related task   Perfect totient numbers Also see   Wikipedia: Euler's totient function.   MathWorld: totient function.   OEIS: Euler totient function phi(n).
#Perl
Perl
use utf8; binmode STDOUT, ":utf8";   sub gcd { my ($u, $v) = @_; while ($v) { ($u, $v) = ($v, $u % $v); } return abs($u); }   push @𝜑, 0; for $t (1..10000) { push @𝜑, scalar grep { 1 == gcd($_,$t) } 1..$t; }   printf "𝜑(%2d) = %3d%s\n", $_, $𝜑[$_], $_ - $𝜑[$_] - 1 ? '' : ' Prime' for 1 .. 25; print "\n";   for $limit (100, 1000, 10000) { printf "Count of primes <= $limit: %d\n", scalar grep {$_ == $𝜑[$_] + 1} 0..$limit; }  
http://rosettacode.org/wiki/Topswops
Topswops
Topswops is a card game created by John Conway in the 1970's. Assume you have a particular permutation of a set of   n   cards numbered   1..n   on both of their faces, for example the arrangement of four cards given by   [2, 4, 1, 3]   where the leftmost card is on top. A round is composed of reversing the first   m   cards where   m   is the value of the topmost card. Rounds are repeated until the topmost card is the number   1   and the number of swaps is recorded. For our example the swaps produce: [2, 4, 1, 3] # Initial shuffle [4, 2, 1, 3] [3, 1, 2, 4] [2, 1, 3, 4] [1, 2, 3, 4] For a total of four swaps from the initial ordering to produce the terminating case where   1   is on top. For a particular number   n   of cards,   topswops(n)   is the maximum swaps needed for any starting permutation of the   n   cards. Task The task is to generate and show here a table of   n   vs   topswops(n)   for   n   in the range   1..10   inclusive. Note Topswops   is also known as   Fannkuch   from the German word   Pfannkuchen   meaning   pancake. Related tasks   Number reversal game   Sorting algorithms/Pancake sort
#XPL0
XPL0
code ChOut=8, CrLf=9, IntOut=11; int N, Max, Card1(16), Card2(16);   proc Topswop(D); \Conway's card swopping game int D; \depth of recursion int I, J, C, T; [if D # N then \generate N! permutations of 1..N in Card1 [for I:= 0 to N-1 do [for J:= 0 to D-1 do \check if object (letter) already used if Card1(J) = I+1 then J:=100; if J < 100 then [Card1(D):= I+1; \card number not used so append it Topswop(D+1); \recurse next level deeper ]; ]; ] else [\determine number of topswops to get card 1 at beginning for I:= 0 to N-1 do Card2(I):= Card1(I); \make working copy of deck C:= 0; \initialize swop counter while Card2(0) # 1 do [I:= 0; J:= Card2(0)-1; while I < J do [T:= Card2(I); Card2(I):= Card2(J); Card2(J):= T; I:= I+1; J:= J-1; ]; C:= C+1; ]; if C>Max then Max:= C; ]; ];   [for N:= 1 to 10 do [Max:= 0; Topswop(0); IntOut(0, N); ChOut(0, ^ ); IntOut(0, Max); CrLf(0); ]; ]
http://rosettacode.org/wiki/Topswops
Topswops
Topswops is a card game created by John Conway in the 1970's. Assume you have a particular permutation of a set of   n   cards numbered   1..n   on both of their faces, for example the arrangement of four cards given by   [2, 4, 1, 3]   where the leftmost card is on top. A round is composed of reversing the first   m   cards where   m   is the value of the topmost card. Rounds are repeated until the topmost card is the number   1   and the number of swaps is recorded. For our example the swaps produce: [2, 4, 1, 3] # Initial shuffle [4, 2, 1, 3] [3, 1, 2, 4] [2, 1, 3, 4] [1, 2, 3, 4] For a total of four swaps from the initial ordering to produce the terminating case where   1   is on top. For a particular number   n   of cards,   topswops(n)   is the maximum swaps needed for any starting permutation of the   n   cards. Task The task is to generate and show here a table of   n   vs   topswops(n)   for   n   in the range   1..10   inclusive. Note Topswops   is also known as   Fannkuch   from the German word   Pfannkuchen   meaning   pancake. Related tasks   Number reversal game   Sorting algorithms/Pancake sort
#zkl
zkl
fcn topswops(n){ flip:=fcn(xa){ if (not xa[0]) return(0); xa.reverse(0,xa[0]+1); // inplace, ~4x faster than making new lists return(1 + self.fcn(xa)); }; (0).pump(n,List):Utils.Helpers.permute(_).pump(List,"copy",flip).reduce("max"); }   foreach n in ([1 .. 10]){ println(n, ": ", topswops(n)) }
http://rosettacode.org/wiki/Trigonometric_functions
Trigonometric functions
Task If your language has a library or built-in functions for trigonometry, show examples of:   sine   cosine   tangent   inverses   (of the above) using the same angle in radians and degrees. For the non-inverse functions,   each radian/degree pair should use arguments that evaluate to the same angle   (that is, it's not necessary to use the same angle for all three regular functions as long as the two sine calls use the same angle). For the inverse functions,   use the same number and convert its answer to radians and degrees. If your language does not have trigonometric functions available or only has some available,   write functions to calculate the functions based on any   known approximation or identity.
#Groovy
Groovy
def radians = Math.PI/4 def degrees = 45   def d2r = { it*Math.PI/180 } def r2d = { it*180/Math.PI }   println "sin(\u03C0/4) = ${Math.sin(radians)} == sin(45\u00B0) = ${Math.sin(d2r(degrees))}" println "cos(\u03C0/4) = ${Math.cos(radians)} == cos(45\u00B0) = ${Math.cos(d2r(degrees))}" println "tan(\u03C0/4) = ${Math.tan(radians)} == tan(45\u00B0) = ${Math.tan(d2r(degrees))}" println "asin(\u221A2/2) = ${Math.asin(2**(-0.5))} == asin(\u221A2/2)\u00B0 = ${r2d(Math.asin(2**(-0.5)))}\u00B0" println "acos(\u221A2/2) = ${Math.acos(2**(-0.5))} == acos(\u221A2/2)\u00B0 = ${r2d(Math.acos(2**(-0.5)))}\u00B0" println "atan(1) = ${Math.atan(1)} == atan(1)\u00B0 = ${r2d(Math.atan(1))}\u00B0"
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#Python
Python
Python 3.2.2 (default, Sep 4 2011, 09:51:08) [MSC v.1500 32 bit (Intel)] on win32 Type "copyright", "credits" or "license()" for more information. >>> def f(x): return abs(x) ** 0.5 + 5 * x**3   >>> print(', '.join('%s:%s' % (x, v if v<=400 else "TOO LARGE!") for x,v in ((y, f(float(y))) for y in input('\nnumbers: ').strip().split()[:11][::-1])))   11 numbers: 1 2 3 4 5 6 7 8 9 10 11 11:TOO LARGE!, 10:TOO LARGE!, 9:TOO LARGE!, 8:TOO LARGE!, 7:TOO LARGE!, 6:TOO LARGE!, 5:TOO LARGE!, 4:322.0, 3:136.73205080756887, 2:41.41421356237309, 1:6.0 >>>
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#R
R
S <- scan(n=11)   f <- function(x) sqrt(abs(x)) + 5*x^3   for (i in rev(S)) { res <- f(i) if (res > 400) print("Too large!") else print(res) }
http://rosettacode.org/wiki/Truncatable_primes
Truncatable primes
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 739, 73, and 7 formed by removing digits from its right are also prime. No zeroes are allowed in truncatable primes. Task The task is to find the largest left-truncatable and right-truncatable primes less than one million (base 10 is implied). Related tasks Find largest left truncatable prime in a given base Sieve of Eratosthenes See also Truncatable Prime from MathWorld.]
#PureBasic
PureBasic
#MaxLim = 999999   Procedure is_Prime(n) If n<=1 : ProcedureReturn #False ElseIf n<4  : ProcedureReturn #True ElseIf n%2=0: ProcedureReturn #False ElseIf n<9  : ProcedureReturn #True ElseIf n%3=0: ProcedureReturn #False Else Protected r=Round(Sqr(n),#PB_Round_Down) Protected f=5 While f<=r If n%f=0 Or n%(f+2)=0 ProcedureReturn #False EndIf f+6 Wend EndIf ProcedureReturn #True EndProcedure   Procedure TruncateLeft(n) Protected s.s=Str(n), l=Len(s)-1 If Not FindString(s,"0",1) While l>0 s=Right(s,l) If Not is_Prime(Val(s)) ProcedureReturn #False EndIf l-1 Wend ProcedureReturn #True EndIf EndProcedure   Procedure TruncateRight(a) Repeat a/10 If Not a Break ElseIf Not is_Prime(a) Or a%10=0 ProcedureReturn #False EndIf ForEver ProcedureReturn #True EndProcedure   i=#MaxLim Repeat If is_Prime(i) If Not truncateleft And TruncateLeft(i) truncateleft=i EndIf If Not truncateright And TruncateRight(i) truncateright=i EndIf EndIf If truncateleft And truncateright Break Else i-2 EndIf Until i<=0   x.s="Largest TruncateLeft= "+Str(truncateleft) y.s="Largest TruncateRight= "+Str(truncateright)   MessageRequester("Truncatable primes",x+#CRLF$+y)
http://rosettacode.org/wiki/Tree_traversal
Tree traversal
Task Implement a binary tree where each node carries an integer,   and implement:   pre-order,   in-order,   post-order,     and   level-order   traversal. Use those traversals to output the following tree: 1 / \ / \ / \ 2 3 / \ / 4 5 6 / / \ 7 8 9 The correct output should look like this: preorder: 1 2 4 7 5 3 6 8 9 inorder: 7 4 2 5 1 8 6 9 3 postorder: 7 4 5 2 8 9 6 3 1 level-order: 1 2 3 4 5 6 7 8 9 See also   Wikipedia article:   Tree traversal.
#Elena
Elena
import extensions; import extensions'routines; import system'collections;   singleton DummyNode { get generic() = EmptyEnumerable; }   class Node { rprop int Value; rprop Node Left; rprop Node Right;   constructor new(int value) { Value := value }   constructor new(int value, Node left) { Value := value; Left := left; }   constructor new(int value, Node left, Node right) { Value := value; Left := left; Right := right }   Preorder = new Enumerable { Enumerator enumerator() = CompoundEnumerator.new( SingleEnumerable.new(Value), (Left ?? DummyNode).Preorder, (Right ?? DummyNode).Preorder); };   Inorder = new Enumerable { Enumerator enumerator() { if (nil != Left) { ^ CompoundEnumerator.new(Left.Inorder, SingleEnumerable.new(Value), (Right ?? DummyNode).Inorder) } else { ^ SingleEnumerable.new(Value).enumerator() } } };   Postorder = new Enumerable { Enumerator enumerator() { if (nil == Left) { ^ SingleEnumerable.new(Value).enumerator() } else if (nil == Right) { ^ CompoundEnumerator.new(Left.Postorder, SingleEnumerable.new(Value)) } else { ^ CompoundEnumerator.new(Left.Postorder, Right.Postorder, SingleEnumerable.new(Value)) } } };   LevelOrder = new Enumerable { Queue<Node> queue := class Queue<Node>.allocate(4).push:self;   Enumerator enumerator() = new Enumerator { bool next() = queue.isNotEmpty();   get() { Node item := queue.pop(); Node left := item.Left; Node right := item.Right;   if (nil != left) { queue.push(left) }; if (nil != right) { queue.push(right) };   ^ item.Value }   reset() { NotSupportedException.raise() }   enumerable() = queue; }; }; }   public program() { var tree := Node.new(1, Node.new(2, Node.new(4, Node.new(7)), Node.new(5)), Node.new(3, Node.new(6, Node.new(8), Node.new(9))));   console.printLine("Preorder  :", tree.Preorder); console.printLine("Inorder  :", tree.Inorder); console.printLine("Postorder :", tree.Postorder); console.printLine("LevelOrder:", tree.LevelOrder) }
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#COBOL
COBOL
  identification division. program-id. tokenize.   environment division. configuration section. repository. function all intrinsic.   data division. working-storage section. 01 period constant as ".". 01 cmma constant as ",".   01 start-with. 05 value "Hello,How,Are,You,Today".   01 items. 05 item pic x(6) occurs 5 times.   procedure division. tokenize-main. unstring start-with delimited by cmma into item(1) item(2) item(3) item(4) item(5)   display trim(item(1)) period trim(item(2)) period trim(item(3)) period trim(item(4)) period trim(item(5))   goback. end program tokenize.  
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Clojure
Clojure
  (defn fib [] (map first (iterate (fn [[a b]] [b (+ a b)]) [0 1])))   (time (take 100 (fib)))  
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#Common_Lisp
Common Lisp
CL-USER> (time (reduce #'+ (make-list 100000 :initial-element 1))) Evaluation took: 0.151 seconds of real time 0.019035 seconds of user run time 0.01807 seconds of system run time 0 calls to %EVAL 0 page faults and 2,400,256 bytes consed.
http://rosettacode.org/wiki/Top_rank_per_group
Top rank per group
Task Find the top   N   salaries in each department,   where   N   is provided as a parameter. Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source: Employee Name,Employee ID,Salary,Department Tyler Bennett,E10297,32000,D101 John Rappl,E21437,47000,D050 George Woltman,E00127,53500,D101 Adam Smith,E63535,18000,D202 Claire Buckman,E39876,27800,D202 David McClellan,E04242,41500,D101 Rich Holcomb,E01234,49500,D202 Nathan Adams,E41298,21900,D050 Richard Potter,E43128,15900,D101 David Motsinger,E27002,19250,D202 Tim Sampair,E03033,27000,D101 Kim Arlich,E10001,57000,D190 Timothy Grove,E16398,29900,D190
#Elena
Elena
import system'collections; import system'routines; import extensions; import extensions'routines; import extensions'text;   class Employee { prop string Name; prop string ID; prop int Salary; prop string Department;   string toPrintable() = new StringWriter() .writePaddingRight(Name, 25) .writePaddingRight(ID, 12) .writePaddingRight(Salary.toPrintable(), 12) .write:Department; }   extension reportOp { topNPerDepartment(n) = self.groupBy:(x => x.Department ).selectBy:(x) { ^ new { Department = x.Key;   Employees = x.orderBy:(f,l => f.Salary > l.Salary ).top(n).summarize(new ArrayList()); } }; }   public program() { var employees := new Employee[] { new Employee{ this Name := "Tyler Bennett"; this ID := "E10297"; this Salary:=32000; this Department:="D101";}, new Employee{ this Name := "John Rappl"; this ID := "E21437"; this Salary:=47000; this Department:="D050";}, new Employee{ this Name := "George Woltman"; this ID := "E00127"; this Salary:=53500; this Department:="D101";}, new Employee{ this Name := "Adam Smith"; this ID := "E63535"; this Salary:=18000; this Department:="D202";}, new Employee{ this Name := "Claire Buckman"; this ID := "E39876"; this Salary:=27800; this Department:="D202";}, new Employee{ this Name := "David McClellan"; this ID := "E04242"; this Salary:=41500; this Department:="D101";}, new Employee{ this Name := "Rich Holcomb"; this ID := "E01234"; this Salary:=49500; this Department:="D202";}, new Employee{ this Name := "Nathan Adams"; this ID := "E41298"; this Salary:=21900; this Department:="D050";}, new Employee{ this Name := "Richard Potter"; this ID := "E43128"; this Salary:=15900; this Department:="D101";}, new Employee{ this Name := "David Motsinger"; this ID := "E27002"; this Salary:=19250; this Department:="D202";}, new Employee{ this Name := "Tim Sampair"; this ID := "E03033"; this Salary:=27000; this Department:="D101";}, new Employee{ this Name := "Kim Arlich"; this ID := "E10001"; this Salary:=57000; this Department:="D190";}, new Employee{ this Name := "Timothy Grove"; this ID := "E16398"; this Salary:=29900; this Department:="D190";} };   employees.topNPerDepartment:2.forEach:(info) { console.printLine("Department: ",info.Department);   info.Employees.forEach:printingLn;   console.writeLine:"---------------------------------------------" };   console.readChar() }
http://rosettacode.org/wiki/Tic-tac-toe
Tic-tac-toe
Task Play a game of tic-tac-toe. Ensure that legal moves are played and that a winning position is notified. Tic-tac-toe   is also known as:   naughts and crosses   tic tac toe   tick tack toe   three in a row   tres en rayo       and   Xs  and  Os See also   MathWorld™, Tic-Tac-Toe game.   Wikipedia tic-tac-toe.
#C
C
#include <stdio.h> #include <stdlib.h>   int b[3][3]; /* board. 0: blank; -1: computer; 1: human */   int check_winner() { int i; for (i = 0; i < 3; i++) { if (b[i][0] && b[i][1] == b[i][0] && b[i][2] == b[i][0]) return b[i][0]; if (b[0][i] && b[1][i] == b[0][i] && b[2][i] == b[0][i]) return b[0][i]; } if (!b[1][1]) return 0;   if (b[1][1] == b[0][0] && b[2][2] == b[0][0]) return b[0][0]; if (b[1][1] == b[2][0] && b[0][2] == b[1][1]) return b[1][1];   return 0; }   void showboard() { const char *t = "X O"; int i, j; for (i = 0; i < 3; i++, putchar('\n')) for (j = 0; j < 3; j++) printf("%c ", t[ b[i][j] + 1 ]); printf("-----\n"); }   #define for_ij for (i = 0; i < 3; i++) for (j = 0; j < 3; j++) int best_i, best_j; int test_move(int val, int depth) { int i, j, score; int best = -1, changed = 0;   if ((score = check_winner())) return (score == val) ? 1 : -1;   for_ij { if (b[i][j]) continue;   changed = b[i][j] = val; score = -test_move(-val, depth + 1); b[i][j] = 0;   if (score <= best) continue; if (!depth) { best_i = i; best_j = j; } best = score; }   return changed ? best : 0; }   const char* game(int user) { int i, j, k, move, win = 0; for_ij b[i][j] = 0;   printf("Board postions are numbered so:\n1 2 3\n4 5 6\n7 8 9\n"); printf("You have O, I have X.\n\n"); for (k = 0; k < 9; k++, user = !user) { while(user) { printf("your move: "); if (!scanf("%d", &move)) { scanf("%*s"); continue; } if (--move < 0 || move >= 9) continue; if (b[i = move / 3][j = move % 3]) continue;   b[i][j] = 1; break; } if (!user) { if (!k) { /* randomize if computer opens, less boring */ best_i = rand() % 3; best_j = rand() % 3; } else test_move(-1, 0);   b[best_i][best_j] = -1; printf("My move: %d\n", best_i * 3 + best_j + 1); }   showboard(); if ((win = check_winner())) return win == 1 ? "You win.\n\n": "I win.\n\n"; } return "A draw.\n\n"; }   int main() { int first = 0; while (1) printf("%s", game(first = !first)); return 0; }
http://rosettacode.org/wiki/Towers_of_Hanoi
Towers of Hanoi
Task Solve the   Towers of Hanoi   problem with recursion.
#Befunge
Befunge
48*2+1>#v_:!#@_0" ksid evoM">:#,_$:8/:.v >8v8:<$#<+9-+*2%3\*3/3:,+55.+1%3:$_,#!>#:< : >/!#^_:0\:8/1-8vv,_$8%:3/1+.>0" gep ot"^ ^++3-%3\*2/3:%8\*<>:^:"from peg "0\*8-1<
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#Lambdatalk
Lambdatalk
    {def thue_morse {def thue_morse.r {lambda {:steps :s1 :s2 :i} {if {> :i :steps} then :s1 else {thue_morse.r :steps :s1:s2 :s2:s1 {+ :i 1}}}}} {lambda {:steps} {thue_morse.r :steps 0 1 1}}} -> thue_morse   {thue_morse 6} -> 0110100110010110100101100110100110010110011010010110100110010110    
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#Lua
Lua
ThueMorse = {sequence = "0"}   function ThueMorse:show () print(self.sequence) end   function ThueMorse:addBlock () local newBlock = "" for bit = 1, self.sequence:len() do if self.sequence:sub(bit, bit) == "1" then newBlock = newBlock .. "0" else newBlock = newBlock .. "1" end end self.sequence = self.sequence .. newBlock end   for i = 1, 5 do ThueMorse:show() ThueMorse:addBlock() end
http://rosettacode.org/wiki/Tonelli-Shanks_algorithm
Tonelli-Shanks algorithm
This page uses content from Wikipedia. The original article was at Tonelli-Shanks algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In computational number theory, the Tonelli–Shanks algorithm is a technique for solving for x in a congruence of the form: x2 ≡ n (mod p) where n is an integer which is a quadratic residue (mod p), p is an odd prime, and x,n ∈ Fp where Fp = {0, 1, ..., p - 1}. It is used in cryptography techniques. To apply the algorithm, we need the Legendre symbol: The Legendre symbol (a | p) denotes the value of a(p-1)/2 (mod p). (a | p) ≡ 1    if a is a square (mod p) (a | p) ≡ -1    if a is not a square (mod p) (a | p) ≡ 0    if a ≡ 0 (mod p) Algorithm pseudo-code All ≡ are taken to mean (mod p) unless stated otherwise. Input: p an odd prime, and an integer n . Step 0: Check that n is indeed a square: (n | p) must be ≡ 1 . Step 1: By factoring out powers of 2 from p - 1, find q and s such that p - 1 = q2s with q odd . If p ≡ 3 (mod 4) (i.e. s = 1), output the two solutions r ≡ ± n(p+1)/4 . Step 2: Select a non-square z such that (z | p) ≡ -1 and set c ≡ zq . Step 3: Set r ≡ n(q+1)/2, t ≡ nq, m = s . Step 4: Loop the following: If t ≡ 1, output r and p - r . Otherwise find, by repeated squaring, the lowest i, 0 < i < m , such that t2i ≡ 1 . Let b ≡ c2(m - i - 1), and set r ≡ rb, t ≡ tb2, c ≡ b2 and m = i . Task Implement the above algorithm. Find solutions (if any) for n = 10 p = 13 n = 56 p = 101 n = 1030 p = 10009 n = 1032 p = 10009 n = 44402 p = 100049 Extra credit n = 665820697 p = 1000000009 n = 881398088036 p = 1000000000039 n = 41660815127637347468140745042827704103445750172002 p = 10^50 + 577 See also Modular exponentiation Cipolla's algorithm
#Wren
Wren
import "/dynamic" for Tuple import "/big" for BigInt   var Solution = Tuple.create("Solution", ["root1", "root2", "exists"])   var ts = Fn.new { |n, p| if (n is Num) n = BigInt.new(n) if (p is Num) p = BigInt.new(p)   var powModP = Fn.new { |a, e| a.modPow(e, p) }   var ls = Fn.new { |a| powModP.call(a, p.dec / BigInt.two) }   if (ls.call(n) != BigInt.one) return Solution.new(BigInt.zero, BigInt.zero, false) var q = p.dec var ss = BigInt.zero while (q & BigInt.one == BigInt.zero) { ss = ss.inc q = q >> 1 } if (ss == BigInt.one) { var r1 = powModP.call(n, p.inc / BigInt.four) return Solution.new(r1, p - r1, true) } var z = BigInt.two while (ls.call(z) != p.dec) z = z.inc var c = powModP.call(z, q) var r = powModP.call(n, q.inc/BigInt.two) var t = powModP.call(n, q) var m = ss while (true) { if (t == BigInt.one) return Solution.new(r, p - r, true) var i = BigInt.zero var zz = t while (zz != BigInt.one && i < m.dec) { zz = zz * zz % p i = i.inc } var b = c var e = m - i.inc while (e > BigInt.zero) { b = b * b % p e = e.dec } r = r * b % p c = b * b % p t = t * c % p m = i } }   var pairs = [ [10, 13], [56, 101], [1030, 10009], [1032, 10009], [44402, 100049], [665820697, 1000000009], [881398088036, 1000000000039] ]   for (pair in pairs) { var n = pair[0] var p = pair[1] var sol = ts.call(n, p) System.print("n = %(n)") System.print("p = %(p)") if (sol.exists) { System.print("root1 = %(sol.root1)") System.print("root2 = %(sol.root2)") } else { System.print("No solution exists") } System.print() }   var bn = BigInt.new("41660815127637347468140745042827704103445750172002") var bp = BigInt.ten.pow(50) + BigInt.new(577) var bsol = ts.call(bn, bp) System.print("n = %(bn)") System.print("p = %(bp)") if (bsol.exists) { System.print("root1 = %(bsol.root1)") System.print("root2 = %(bsol.root2)") } else { System.print("No solution exists") }
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Lingo
Lingo
-- in some movie script   on tokenize (str, sep, esc) l = [] _player.itemDelimiter = sep cnt = str.item.count repeat with i = 1 to cnt prev = l.getLast() -- can be VOID if _trailEscCount(prev, esc) mod 2 then l[l.count] = prev.char[1..prev.length-1]&sep&str.item[i] else l.add(str.item[i]) end if end repeat -- remove escape characters from tokens cnt = l.count repeat with i = 1 to cnt l[i] = _removeEsc(l[i], esc) end repeat return l end   -- counts number of trailing escape characters on _trailEscCount (str, esc) n = 0 repeat with i = str.length down to 1 if str.char[i]=esc then n=n+1 else exit repeat end repeat return n end   -- could be implemented more efficiently by using offset() on _removeEsc (str, esc) cnt = str.length-1 repeat with i = 1 to cnt if str.char[i]=esc then delete char i of str cnt = cnt-1 end if end repeat return str end
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Lua
Lua
function tokenise (str, sep, esc) local strList, word, escaped, ch = {}, "", false for pos = 1, #str do ch = str:sub(pos, pos) if ch == esc then if escaped then word = word .. ch escaped = false else escaped = true end elseif ch == sep then if escaped then word = word .. ch escaped = false else table.insert(strList, word) word = "" end else escaped = false word = word .. ch end end table.insert(strList, word) return strList end   local testStr = "one^|uno||three^^^^|four^^^|^cuatro|" local testSep, testEsc = "|", "^" for k, v in pairs(tokenise(testStr, testSep, testEsc)) do print(k, v) end
http://rosettacode.org/wiki/Topological_sort
Topological sort
Sorting Algorithm This is a sorting algorithm.   It may be applied to a set of data in order to sort it.     For comparing various sorts, see compare sorts.   For other sorting algorithms,   see sorting algorithms,   or: O(n logn) sorts Heap sort | Merge sort | Patience sort | Quick sort O(n log2n) sorts Shell Sort O(n2) sorts Bubble sort | Cocktail sort | Cocktail sort with shifting bounds | Comb sort | Cycle sort | Gnome sort | Insertion sort | Selection sort | Strand sort other sorts Bead sort | Bogo sort | Common sorted list | Composite structures sort | Custom comparator sort | Counting sort | Disjoint sublist sort | External sort | Jort sort | Lexicographical sort | Natural sorting | Order by pair comparisons | Order disjoint list items | Order two numerical lists | Object identifier (OID) sort | Pancake sort | Quickselect | Permutation sort | Radix sort | Ranking methods | Remove duplicate elements | Sleep sort | Stooge sort | [Sort letters of a string] | Three variable sort | Topological sort | Tree sort Given a mapping between items, and items they depend on, a topological sort orders items so that no item precedes an item it depends upon. The compiling of a library in the VHDL language has the constraint that a library must be compiled after any library it depends on. A tool exists that extracts library dependencies. Task Write a function that will return a valid compile order of VHDL libraries from their dependencies. Assume library names are single words. Items mentioned as only dependents, (sic), have no dependents of their own, but their order of compiling must be given. Any self dependencies should be ignored. Any un-orderable dependencies should be flagged. Use the following data as an example: LIBRARY LIBRARY DEPENDENCIES ======= ==================== des_system_lib std synopsys std_cell_lib des_system_lib dw02 dw01 ramlib ieee dw01 ieee dw01 dware gtech dw02 ieee dw02 dware dw03 std synopsys dware dw03 dw02 dw01 ieee gtech dw04 dw04 ieee dw01 dware gtech dw05 dw05 ieee dware dw06 dw06 ieee dware dw07 ieee dware dware ieee dware gtech ieee gtech ramlib std ieee std_cell_lib ieee std_cell_lib synopsys Note: the above data would be un-orderable if, for example, dw04 is added to the list of dependencies of dw01. C.f.   Topological sort/Extracted top item. There are two popular algorithms for topological sorting:   Kahn's 1962 topological sort [1]   depth-first search [2] [3]
#J
J
dependencySort=: monad define parsed=. <@;:;._2 y names=. {.&>parsed depends=. (> =@i.@#) names e.S:1 parsed depends=. (+. +./ .*.~)^:_ depends assert.-.1 e. (<0 1)|:depends (-.&names ~.;parsed),names /: +/"1 depends )
http://rosettacode.org/wiki/Universal_Turing_machine
Universal Turing machine
One of the foundational mathematical constructs behind computer science is the universal Turing Machine. (Alan Turing introduced the idea of such a machine in 1936–1937.) Indeed one way to definitively prove that a language is turing-complete is to implement a universal Turing machine in it. Task Simulate such a machine capable of taking the definition of any other Turing machine and executing it. Of course, you will not have an infinite tape, but you should emulate this as much as is possible. The three permissible actions on the tape are "left", "right" and "stay". To test your universal Turing machine (and prove your programming language is Turing complete!), you should execute the following two Turing machines based on the following definitions. Simple incrementer States: q0, qf Initial state: q0 Terminating states: qf Permissible symbols: B, 1 Blank symbol: B Rules: (q0, 1, 1, right, q0) (q0, B, 1, stay, qf) The input for this machine should be a tape of 1 1 1 Three-state busy beaver States: a, b, c, halt Initial state: a Terminating states: halt Permissible symbols: 0, 1 Blank symbol: 0 Rules: (a, 0, 1, right, b) (a, 1, 1, left, c) (b, 0, 1, left, a) (b, 1, 1, right, b) (c, 0, 1, left, b) (c, 1, 1, stay, halt) The input for this machine should be an empty tape. Bonus: 5-state, 2-symbol probable Busy Beaver machine from Wikipedia States: A, B, C, D, E, H Initial state: A Terminating states: H Permissible symbols: 0, 1 Blank symbol: 0 Rules: (A, 0, 1, right, B) (A, 1, 1, left, C) (B, 0, 1, right, C) (B, 1, 1, right, B) (C, 0, 1, right, D) (C, 1, 0, left, E) (D, 0, 1, left, A) (D, 1, 1, left, D) (E, 0, 1, stay, H) (E, 1, 0, left, A) The input for this machine should be an empty tape. This machine runs for more than 47 millions steps.
#Perl
Perl
use strict; use warnings;   sub run_utm { my %o = @_; my $st = $o{state} // die "init head state undefined"; my $blank = $o{blank} // die "blank symbol undefined"; my @rules = @{$o{rules}} or die "rules undefined"; my @tape = $o{tape} ? @{$o{tape}} : ($blank); my $halt = $o{halt};   my $pos = $o{pos} // 0; $pos += @tape if $pos < 0; die "bad init position" if $pos >= @tape || $pos < 0;   step: while (1) { print "$st\t"; for (0 .. $#tape) { my $v = $tape[$_]; print $_ == $pos ? "[$v]" : " $v "; } print "\n";   last if $st eq $halt; for (@rules) { my ($s0, $v0, $v1, $dir, $s1) = @$_; next unless $s0 eq $st and $tape[$pos] eq $v0;   $tape[$pos] = $v1;   if ($dir eq 'left') { if ($pos == 0) { unshift @tape, $blank} else { $pos-- } } elsif ($dir eq 'right') { push @tape, $blank if ++$pos >= @tape }   $st = $s1; next step; }   die "no matching rules"; } }   print "incr machine\n"; run_utm halt=>'qf', state=>'q0', tape=>[1,1,1], blank=>'B', rules=>[[qw/q0 1 1 right q0/], [qw/q0 B 1 stay qf/]];   print "\nbusy beaver\n"; run_utm halt=>'halt', state=>'a', blank=>'0', rules=>[[qw/a 0 1 right b/], [qw/a 1 1 left c/], [qw/b 0 1 left a/], [qw/b 1 1 right b/], [qw/c 0 1 left b/], [qw/c 1 1 stay halt/]];   print "\nsorting test\n"; run_utm halt=>'STOP', state=>'A', blank=>'0', tape=>[qw/2 2 2 1 2 2 1 2 1 2 1 2 1 2/], rules=>[[qw/A 1 1 right A/], [qw/A 2 3 right B/], [qw/A 0 0 left E/], [qw/B 1 1 right B/], [qw/B 2 2 right B/], [qw/B 0 0 left C/], [qw/C 1 2 left D/], [qw/C 2 2 left C/], [qw/C 3 2 left E/], [qw/D 1 1 left D/], [qw/D 2 2 left D/], [qw/D 3 1 right A/], [qw/E 1 1 left E/], [qw/E 0 0 right STOP/]];
http://rosettacode.org/wiki/Totient_function
Totient function
The   totient   function is also known as:   Euler's totient function   Euler's phi totient function   phi totient function   Φ   function   (uppercase Greek phi)   φ    function   (lowercase Greek phi) Definitions   (as per number theory) The totient function:   counts the integers up to a given positive integer   n   that are relatively prime to   n   counts the integers   k   in the range   1 ≤ k ≤ n   for which the greatest common divisor   gcd(n,k)   is equal to   1   counts numbers   ≤ n   and   prime to   n If the totient number   (for N)   is one less than   N,   then   N   is prime. Task Create a   totient   function and:   Find and display   (1 per line)   for the 1st   25   integers:   the integer   (the index)   the totient number for that integer   indicate if that integer is prime   Find and display the   count   of the primes up to          100   Find and display the   count   of the primes up to       1,000   Find and display the   count   of the primes up to     10,000   Find and display the   count   of the primes up to   100,000     (optional) Show all output here. Related task   Perfect totient numbers Also see   Wikipedia: Euler's totient function.   MathWorld: totient function.   OEIS: Euler totient function phi(n).
#Phix
Phix
function totient(integer n) integer tot = n, i = 2 while i*i<=n do if mod(n,i)=0 then while true do n /= i if mod(n,i)!=0 then exit end if end while tot -= tot/i end if i += iff(i=2?1:2) end while if n>1 then tot -= tot/n end if return tot end function printf(1," n phi prime\n") printf(1," --------------\n") integer count = 0 for n=1 to 25 do integer tot = totient(n), prime = (n-1=tot) count += prime string isp = iff(prime?"true":"false") printf(1,"%2d  %2d  %s\n",{n,tot,isp}) end for printf(1,"\nNumber of primes up to 25 = %d\n",count) for n=26 to 100000 do count += (totient(n)=n-1) if find(n,{100,1000,10000,100000}) then printf(1,"Number of primes up to %-6d = %d\n",{n,count}) end if end for
http://rosettacode.org/wiki/Trigonometric_functions
Trigonometric functions
Task If your language has a library or built-in functions for trigonometry, show examples of:   sine   cosine   tangent   inverses   (of the above) using the same angle in radians and degrees. For the non-inverse functions,   each radian/degree pair should use arguments that evaluate to the same angle   (that is, it's not necessary to use the same angle for all three regular functions as long as the two sine calls use the same angle). For the inverse functions,   use the same number and convert its answer to radians and degrees. If your language does not have trigonometric functions available or only has some available,   write functions to calculate the functions based on any   known approximation or identity.
#Haskell
Haskell
fromDegrees :: Floating a => a -> a fromDegrees deg = deg * pi / 180   toDegrees :: Floating a => a -> a toDegrees rad = rad * 180 / pi   main :: IO () main = mapM_ print [ sin (pi / 6) , sin (fromDegrees 30) , cos (pi / 6) , cos (fromDegrees 30) , tan (pi / 6) , tan (fromDegrees 30) , asin 0.5 , toDegrees (asin 0.5) , acos 0.5 , toDegrees (acos 0.5) , atan 0.5 , toDegrees (atan 0.5) ]
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#Racket
Racket
  #lang racket   (define input (for/list ([i 11]) (printf "Enter a number (~a of 11): " (+ 1 i)) (read)))   (for ([x (reverse input)]) (define res (+ (sqrt (abs x)) (* 5 (expt x 3)))) (if (> res 400) (displayln "Overflow!") (printf "f(~a) = ~a\n" x res)))  
http://rosettacode.org/wiki/Trabb_Pardo%E2%80%93Knuth_algorithm
Trabb Pardo–Knuth algorithm
The TPK algorithm is an early example of a programming chrestomathy. It was used in Donald Knuth and Luis Trabb Pardo's Stanford tech report The Early Development of Programming Languages. The report traces the early history of work in developing computer languages in the 1940s and 1950s, giving several translations of the algorithm. From the wikipedia entry: ask for 11 numbers to be read into a sequence S reverse sequence S for each item in sequence S result := call a function to do an operation if result overflows alert user else print result The task is to implement the algorithm: Use the function:     f ( x ) = | x | 0.5 + 5 x 3 {\displaystyle f(x)=|x|^{0.5}+5x^{3}} The overflow condition is an answer of greater than 400. The 'user alert' should not stop processing of other items of the sequence. Print a prompt before accepting eleven, textual, numeric inputs. You may optionally print the item as well as its associated result, but the results must be in reverse order of input. The sequence   S   may be 'implied' and so not shown explicitly. Print and show the program in action from a typical run here. (If the output is graphical rather than text then either add a screendump or describe textually what is displayed).
#Raku
Raku
my @nums = prompt("Please type 11 space-separated numbers: ").words until @nums == 11; for @nums.reverse -> $n { my $r = $n.abs.sqrt + 5 * $n ** 3; say "$n\t{ $r > 400 ?? 'Urk!' !! $r }"; }
http://rosettacode.org/wiki/Truncatable_primes
Truncatable primes
A truncatable prime is a prime number that when you successively remove digits from one end of the prime, you are left with a new prime number. Examples The number 997 is called a left-truncatable prime as the numbers 997, 97, and 7 are all prime. The number 7393 is a right-truncatable prime as the numbers 7393, 739, 73, and 7 formed by removing digits from its right are also prime. No zeroes are allowed in truncatable primes. Task The task is to find the largest left-truncatable and right-truncatable primes less than one million (base 10 is implied). Related tasks Find largest left truncatable prime in a given base Sieve of Eratosthenes See also Truncatable Prime from MathWorld.]
#Python
Python
maxprime = 1000000   def primes(n): multiples = set() prime = [] for i in range(2, n+1): if i not in multiples: prime.append(i) multiples.update(set(range(i*i, n+1, i))) return prime   def truncatableprime(n): 'Return a longest left and right truncatable primes below n' primelist = [str(x) for x in primes(n)[::-1]] primeset = set(primelist) for n in primelist: # n = 'abc'; [n[i:] for i in range(len(n))] -> ['abc', 'bc', 'c'] alltruncs = set(n[i:] for i in range(len(n))) if alltruncs.issubset(primeset): truncateleft = int(n) break for n in primelist: # n = 'abc'; [n[:i+1] for i in range(len(n))] -> ['a', 'ab', 'abc'] alltruncs = set([n[:i+1] for i in range(len(n))]) if alltruncs.issubset(primeset): truncateright = int(n) break return truncateleft, truncateright   print(truncatableprime(maxprime))
http://rosettacode.org/wiki/Tree_traversal
Tree traversal
Task Implement a binary tree where each node carries an integer,   and implement:   pre-order,   in-order,   post-order,     and   level-order   traversal. Use those traversals to output the following tree: 1 / \ / \ / \ 2 3 / \ / 4 5 6 / / \ 7 8 9 The correct output should look like this: preorder: 1 2 4 7 5 3 6 8 9 inorder: 7 4 2 5 1 8 6 9 3 postorder: 7 4 5 2 8 9 6 3 1 level-order: 1 2 3 4 5 6 7 8 9 See also   Wikipedia article:   Tree traversal.
#Elisa
Elisa
  component BinaryTreeTraversals (Tree, Element); type Tree; type Node = Tree; Tree (LeftTree = Tree, Element, RightTree = Tree) -> Tree; Leaf (Element) -> Node; Node (Tree) -> Node; Item (Node) -> Element;   Preorder (Tree) -> multi (Node); Inorder (Tree) -> multi (Node); Postorder (Tree) -> multi (Node); Level_order(Tree) -> multi (Node); begin Tree (Lefttree, Item, Righttree) = Tree: [ Lefttree; Item; Righttree ]; Leaf (anItem) = Tree (null(Tree), anItem, null(Tree) ); Node (aTree) = aTree; Item (aNode) = aNode.Item;   Preorder (=null(Tree)) = no(Tree); Preorder (T) = ( T, Preorder (T.Lefttree), Preorder (T.Righttree));   Inorder (=null(Tree)) = no(Tree); Inorder (T) = ( Inorder (T.Lefttree), T, Inorder (T.Righttree));   Postorder (=null(Tree)) = no(Tree); Postorder (T) = ( Postorder (T.Lefttree), Postorder (T.Righttree), T);   Level_order(T) = [ Queue = {T}; node = Tree:items(Queue); [ result(node); add(Queue, node.Lefttree) when valid(node.Lefttree); add(Queue, node.Righttree) when valid(node.Righttree); ]; no(Tree); ]; end component BinaryTreeTraversals;  
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#CoffeeScript
CoffeeScript
  arr = "Hello,How,Are,You,Today".split "," console.log arr.join "."  
http://rosettacode.org/wiki/Tokenize_a_string
Tokenize a string
Separate the string "Hello,How,Are,You,Today" by commas into an array (or list) so that each element of it stores a different word. Display the words to the 'user', in the simplest manner possible, separated by a period. To simplify, you may display a trailing period. Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#ColdFusion
ColdFusion
  <cfoutput> <cfset wordListTag = "Hello,How,Are,You,Today"> #Replace( wordListTag, ",", ".", "all" )# </cfoutput>  
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#D
D
import std.stdio, std.datetime;   int identity(int x) { return x; }   int sum(int num) { foreach (i; 0 .. 100_000_000) num += i; return num; }   double timeIt(int function(int) func, int arg) { StopWatch sw; sw.start(); func(arg); sw.stop(); return sw.peek().usecs / 1_000_000.0; }   void main() { writefln("identity(4) takes %f6 seconds.", timeIt(&identity, 4)); writefln("sum(4) takes %f seconds.", timeIt(&sum, 4)); }
http://rosettacode.org/wiki/Time_a_function
Time a function
Task Write a program which uses a timer (with the least granularity available on your system) to time how long a function takes to execute. Whenever possible, use methods which measure only the processing time used by the current process; instead of the difference in system time between start and finish, which could include time used by other processes on the computer. This task is intended as a subtask for Measure relative performance of sorting algorithms implementations.
#E
E
def countTo(x) { println("Counting...") for _ in 1..x {} println("Done!") }   def MX := <unsafe:java.lang.management.makeManagementFactory> def threadMX := MX.getThreadMXBean() require(threadMX.isCurrentThreadCpuTimeSupported()) threadMX.setThreadCpuTimeEnabled(true)   for count in [10000, 100000] { def start := threadMX.getCurrentThreadCpuTime() countTo(count) def finish := threadMX.getCurrentThreadCpuTime() println(`Counting to $count takes ${(finish-start)//1000000}ms`) }
http://rosettacode.org/wiki/Top_rank_per_group
Top rank per group
Task Find the top   N   salaries in each department,   where   N   is provided as a parameter. Use this data as a formatted internal data structure (adapt it to your language-native idioms, rather than parse at runtime), or identify your external data source: Employee Name,Employee ID,Salary,Department Tyler Bennett,E10297,32000,D101 John Rappl,E21437,47000,D050 George Woltman,E00127,53500,D101 Adam Smith,E63535,18000,D202 Claire Buckman,E39876,27800,D202 David McClellan,E04242,41500,D101 Rich Holcomb,E01234,49500,D202 Nathan Adams,E41298,21900,D050 Richard Potter,E43128,15900,D101 David Motsinger,E27002,19250,D202 Tim Sampair,E03033,27000,D101 Kim Arlich,E10001,57000,D190 Timothy Grove,E16398,29900,D190
#Elixir
Elixir
defmodule TopRank do def per_groupe(data, n) do String.split(data, ~r/(\n|\r\n|\r)/, trim: true) |> Enum.drop(1) |> Enum.map(fn person -> String.split(person,",") end) |> Enum.group_by(fn person -> department(person) end) |> Enum.each(fn {department,group} -> IO.puts "Department: #{department}" Enum.sort_by(group, fn person -> -salary(person) end) |> Enum.take(n) |> Enum.each(fn person -> IO.puts str_format(person) end) end) end   defp salary([_,_,x,_]), do: String.to_integer(x) defp department([_,_,_,x]), do: x defp str_format([a,b,c,_]), do: " #{a} - #{b} - #{c} annual salary" end   data = """ Employee Name,Employee ID,Salary,Department Tyler Bennett,E10297,32000,D101 John Rappl,E21437,47000,D050 George Woltman,E00127,53500,D101 Adam Smith,E63535,18000,D202 Claire Buckman,E39876,27800,D202 David McClellan,E04242,41500,D101 Rich Holcomb,E01234,49500,D202 Nathan Adams,E41298,21900,D050 Richard Potter,E43128,15900,D101 David Motsinger,E27002,19250,D202 Tim Sampair,E03033,27000,D101 Kim Arlich,E10001,57000,D190 Timothy Grove,E16398,29900,D190 """ TopRank.per_groupe(data, 3)
http://rosettacode.org/wiki/Tic-tac-toe
Tic-tac-toe
Task Play a game of tic-tac-toe. Ensure that legal moves are played and that a winning position is notified. Tic-tac-toe   is also known as:   naughts and crosses   tic tac toe   tick tack toe   three in a row   tres en rayo       and   Xs  and  Os See also   MathWorld™, Tic-Tac-Toe game.   Wikipedia tic-tac-toe.
#C.23
C#
using System; using System.Collections.Generic; using System.Linq; using System.Text;   namespace RosettaTicTacToe { class Program {   /*================================================================ *Pieces (players and board) *================================================================*/ static string[][] Players = new string[][] { new string[] { "COMPUTER", "X" }, // computer player new string[] { "HUMAN", "O" } // human player };   const int Unplayed = -1; const int Computer = 0; const int Human = 1;   // GameBoard holds index into Players[] (0 or 1) or Unplayed (-1) if location not yet taken static int[] GameBoard = new int[9];   static int[] corners = new int[] { 0, 2, 6, 8 };   static int[][] wins = new int[][] { new int[] { 0, 1, 2 }, new int[] { 3, 4, 5 }, new int[] { 6, 7, 8 }, new int[] { 0, 3, 6 }, new int[] { 1, 4, 7 }, new int[] { 2, 5, 8 }, new int[] { 0, 4, 8 }, new int[] { 2, 4, 6 } };     /*================================================================ *Main Game Loop (this is what runs/controls the game) *================================================================*/ static void Main(string[] args) { while (true) { Console.Clear(); Console.WriteLine("Welcome to Rosetta Code Tic-Tac-Toe for C#."); initializeGameBoard(); displayGameBoard(); int currentPlayer = rnd.Next(0, 2); // current player represented by Players[] index of 0 or 1 Console.WriteLine("The first move goes to {0} who is playing {1}s.\n", playerName(currentPlayer), playerToken(currentPlayer)); while (true) { int thisMove = getMoveFor(currentPlayer); if (thisMove == Unplayed) { Console.WriteLine("{0}, you've quit the game ... am I that good?", playerName(currentPlayer)); break; } playMove(thisMove, currentPlayer); displayGameBoard(); if (isGameWon()) { Console.WriteLine("{0} has won the game!", playerName(currentPlayer)); break; } else if (isGameTied()) { Console.WriteLine("Cat game ... we have a tie."); break; } currentPlayer = getNextPlayer(currentPlayer); } if (!playAgain()) return; } }   /*================================================================ *Move Logic *================================================================*/ static int getMoveFor(int player) { if (player == Human) return getManualMove(player); else { //int selectedMove = getManualMove(player); //int selectedMove = getRandomMove(player); int selectedMove = getSemiRandomMove(player); //int selectedMove = getBestMove(player); Console.WriteLine("{0} selects position {1}.", playerName(player), selectedMove + 1); return selectedMove; } }   static int getManualMove(int player) { while (true) { Console.Write("{0}, enter you move (number): ", playerName(player)); ConsoleKeyInfo keyInfo = Console.ReadKey(); Console.WriteLine(); // keep the display pretty if (keyInfo.Key == ConsoleKey.Escape) return Unplayed; if (keyInfo.Key >= ConsoleKey.D1 && keyInfo.Key <= ConsoleKey.D9) { int move = keyInfo.KeyChar - '1'; // convert to between 0..8, a GameBoard index position. if (GameBoard[move] == Unplayed) return move; else Console.WriteLine("Spot {0} is already taken, please select again.", move + 1); } else Console.WriteLine("Illegal move, please select again.\n"); } }   static int getRandomMove(int player) { int movesLeft = GameBoard.Count(position => position == Unplayed); int x = rnd.Next(0, movesLeft); for (int i = 0; i < GameBoard.Length; i++) // walk board ... { if (GameBoard[i] == Unplayed && x < 0) // until we reach the unplayed move. return i; x--; } return Unplayed; }   // plays random if no winning move or needed block. static int getSemiRandomMove(int player) { int posToPlay; if (checkForWinningMove(player, out posToPlay)) return posToPlay; if (checkForBlockingMove(player, out posToPlay)) return posToPlay; return getRandomMove(player); }   // purposely not implemented (this is the thinking part). static int getBestMove(int player) { return -1; }   static bool checkForWinningMove(int player, out int posToPlay) { posToPlay = Unplayed; foreach (var line in wins) if (twoOfThreeMatchPlayer(player, line, out posToPlay)) return true; return false; }   static bool checkForBlockingMove(int player, out int posToPlay) { posToPlay = Unplayed; foreach (var line in wins) if (twoOfThreeMatchPlayer(getNextPlayer(player), line, out posToPlay)) return true; return false; }   static bool twoOfThreeMatchPlayer(int player, int[] line, out int posToPlay) { int cnt = 0; posToPlay = int.MinValue; foreach (int pos in line) { if (GameBoard[pos] == player) cnt++; else if (GameBoard[pos] == Unplayed) posToPlay = pos; } return cnt == 2 && posToPlay >= 0; }   static void playMove(int boardPosition, int player) { GameBoard[boardPosition] = player; }   static bool isGameWon() { return wins.Any(line => takenBySamePlayer(line[0], line[1], line[2])); }   static bool takenBySamePlayer(int a, int b, int c) { return GameBoard[a] != Unplayed && GameBoard[a] == GameBoard[b] && GameBoard[a] == GameBoard[c]; }   static bool isGameTied() { return !GameBoard.Any(spot => spot == Unplayed); }   /*================================================================ *Misc Methods *================================================================*/ static Random rnd = new Random();   static void initializeGameBoard() { for (int i = 0; i < GameBoard.Length; i++) GameBoard[i] = Unplayed; }   static string playerName(int player) { return Players[player][0]; }   static string playerToken(int player) { return Players[player][1]; }   static int getNextPlayer(int player) { return (player + 1) % 2; }   static void displayGameBoard() { Console.WriteLine(" {0} | {1} | {2}", pieceAt(0), pieceAt(1), pieceAt(2)); Console.WriteLine("---|---|---"); Console.WriteLine(" {0} | {1} | {2}", pieceAt(3), pieceAt(4), pieceAt(5)); Console.WriteLine("---|---|---"); Console.WriteLine(" {0} | {1} | {2}", pieceAt(6), pieceAt(7), pieceAt(8)); Console.WriteLine(); }   static string pieceAt(int boardPosition) { if (GameBoard[boardPosition] == Unplayed) return (boardPosition + 1).ToString(); // display 1..9 on board rather than 0..8 return playerToken(GameBoard[boardPosition]); }   private static bool playAgain() { Console.WriteLine("\nDo you want to play again?"); return Console.ReadKey(false).Key == ConsoleKey.Y; } }   }
http://rosettacode.org/wiki/Towers_of_Hanoi
Towers of Hanoi
Task Solve the   Towers of Hanoi   problem with recursion.
#BQN
BQN
Move ← { 𝕩⊑⊸≤0 ? ⟨⟩; 𝕊 n‿from‿to‿via: l ← 𝕊 ⟨n-1, from, via, to⟩ r ← 𝕊 ⟨n-1, via, to, from⟩ l∾(<from‿to)∾r } {"Move disk from pole "∾(•Fmt 𝕨)∾" to pole "∾•Fmt 𝕩}´˘>Move 4‿1‿2‿3
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
ThueMorse[Range[20]]
http://rosettacode.org/wiki/Thue-Morse
Thue-Morse
Task Create a Thue-Morse sequence. See also   YouTube entry: The Fairest Sharing Sequence Ever   YouTube entry: Math and OCD - My story with the Thue-Morse sequence   Task: Fairshare between two and more
#Modula-2
Modula-2
MODULE ThueMorse; FROM Strings IMPORT Concat; FROM Terminal IMPORT WriteString,WriteLn,ReadChar;   PROCEDURE Sequence(steps : CARDINAL); TYPE String = ARRAY[0..128] OF CHAR; VAR sb1,sb2,tmp : String; i : CARDINAL; BEGIN sb1 := "0"; sb2 := "1";   WHILE i<steps DO tmp := sb1; Concat(sb1, sb2, sb1); Concat(sb2, tmp, sb2); INC(i); END; WriteString(sb1); WriteLn; END Sequence;   BEGIN Sequence(6); ReadChar; END ThueMorse.
http://rosettacode.org/wiki/Tonelli-Shanks_algorithm
Tonelli-Shanks algorithm
This page uses content from Wikipedia. The original article was at Tonelli-Shanks algorithm. The list of authors can be seen in the page history. As with Rosetta Code, the text of Wikipedia is available under the GNU FDL. (See links for details on variance) In computational number theory, the Tonelli–Shanks algorithm is a technique for solving for x in a congruence of the form: x2 ≡ n (mod p) where n is an integer which is a quadratic residue (mod p), p is an odd prime, and x,n ∈ Fp where Fp = {0, 1, ..., p - 1}. It is used in cryptography techniques. To apply the algorithm, we need the Legendre symbol: The Legendre symbol (a | p) denotes the value of a(p-1)/2 (mod p). (a | p) ≡ 1    if a is a square (mod p) (a | p) ≡ -1    if a is not a square (mod p) (a | p) ≡ 0    if a ≡ 0 (mod p) Algorithm pseudo-code All ≡ are taken to mean (mod p) unless stated otherwise. Input: p an odd prime, and an integer n . Step 0: Check that n is indeed a square: (n | p) must be ≡ 1 . Step 1: By factoring out powers of 2 from p - 1, find q and s such that p - 1 = q2s with q odd . If p ≡ 3 (mod 4) (i.e. s = 1), output the two solutions r ≡ ± n(p+1)/4 . Step 2: Select a non-square z such that (z | p) ≡ -1 and set c ≡ zq . Step 3: Set r ≡ n(q+1)/2, t ≡ nq, m = s . Step 4: Loop the following: If t ≡ 1, output r and p - r . Otherwise find, by repeated squaring, the lowest i, 0 < i < m , such that t2i ≡ 1 . Let b ≡ c2(m - i - 1), and set r ≡ rb, t ≡ tb2, c ≡ b2 and m = i . Task Implement the above algorithm. Find solutions (if any) for n = 10 p = 13 n = 56 p = 101 n = 1030 p = 10009 n = 1032 p = 10009 n = 44402 p = 100049 Extra credit n = 665820697 p = 1000000009 n = 881398088036 p = 1000000000039 n = 41660815127637347468140745042827704103445750172002 p = 10^50 + 577 See also Modular exponentiation Cipolla's algorithm
#zkl
zkl
var BN=Import("zklBigNum"); fcn modEq(a,b,p) { (a-b)%p==0 } fcn legendre(a,p){ a.powm((p - 1)/2,p) }   fcn tonelli(n,p){ //(BigInt,Int|BigInt) _assert_(legendre(n,p)==1, "not a square (mod p)"+vm.arglist); q,s:=p-1,0; while(q.isEven){ q/=2; s+=1; } if(s==1) return(n.powm((p+1)/4,p)); z:=[BN(2)..p].filter1('wrap(z){ legendre(z,p)==(p-1) }); c,r,t,m,t2:=z.powm(q,p), n.powm((q+1)/2,p), n.powm(q,p), s, 0; while(not modEq(t,1,p)){ t2=(t*t)%p; i:=1; while(not modEq(t2,1,p)){ i+=1; t2=(t2*t2)%p; } // assert(i<m) b:=c.powm(BN(1).shiftLeft(m-i-1), p); r,c,t,m = (r*b)%p, (b*b)%p, (t*c)%p, i; } r }
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
ClearAll[Tokenize] Tokenize[str_String, escape_String : "^", sep_String : "|"] := Module[{results = {}, token = "", state = 0, a}, a = Characters[str]; Do[ If[state == 0, Switch[c, escape, state = 1 , sep, AppendTo[results, token]; token = ""; , _, token = token <> c; ] , If[state == 1, token = token <> c; state = 0; ] ]   , {c, a} ]; AppendTo[results, token]; results ] Tokenize["one^|uno||three^^^^|four^^^|^cuatro|"]
http://rosettacode.org/wiki/Tokenize_a_string_with_escaping
Tokenize a string with escaping
Task[edit] Write a function or program that can split a string at each non-escaped occurrence of a separator character. It should accept three input parameters:   The string   The separator character   The escape character It should output a list of strings. Details Rules for splitting: The fields that were separated by the separators, become the elements of the output list. Empty fields should be preserved, even at the start and end. Rules for escaping: "Escaped" means preceded by an occurrence of the escape character that is not already escaped itself. When the escape character precedes a character that has no special meaning, it still counts as an escape (but does not do anything special). Each occurrence of the escape character that was used to escape something, should not become part of the output. Test case Demonstrate that your function satisfies the following test-case: Input Output string: one^|uno||three^^^^|four^^^|^cuatro| separator character: | escape character: ^ one|uno three^^ four^|cuatro (Print the output list in any format you like, as long as it is it easy to see what the fields are.) Other tasks related to string operations: Metrics Array length String length Copy a string Empty string  (assignment) Counting Word frequency Letter frequency Jewels and stones I before E except after C Bioinformatics/base count Count occurrences of a substring Count how many vowels and consonants occur in a string Remove/replace XXXX redacted Conjugate a Latin verb Remove vowels from a string String interpolation (included) Strip block comments Strip comments from a string Strip a set of characters from a string Strip whitespace from a string -- top and tail Strip control codes and extended characters from a string Anagrams/Derangements/shuffling Word wheel ABC problem Sattolo cycle Knuth shuffle Ordered words Superpermutation minimisation Textonyms (using a phone text pad) Anagrams Anagrams/Deranged anagrams Permutations/Derangements Find/Search/Determine ABC words Odd words Word ladder Semordnilap Word search Wordiff  (game) String matching Tea cup rim text Alternade words Changeable words State name puzzle String comparison Unique characters Unique characters in each string Extract file extension Levenshtein distance Palindrome detection Common list elements Longest common suffix Longest common prefix Compare a list of strings Longest common substring Find common directory path Words from neighbour ones Change e letters to i in words Non-continuous subsequences Longest common subsequence Longest palindromic substrings Longest increasing subsequence Words containing "the" substring Sum of the digits of n is substring of n Determine if a string is numeric Determine if a string is collapsible Determine if a string is squeezable Determine if a string has all unique characters Determine if a string has all the same characters Longest substrings without repeating characters Find words which contains all the vowels Find words which contains most consonants Find words which contains more than 3 vowels Find words which first and last three letters are equals Find words which odd letters are consonants and even letters are vowels or vice_versa Formatting Substring Rep-string Word wrap String case Align columns Literals/String Repeat a string Brace expansion Brace expansion using ranges Reverse a string Phrase reversals Comma quibbling Special characters String concatenation Substring/Top and tail Commatizing numbers Reverse words in a string Suffixation of decimal numbers Long literals, with continuations Numerical and alphabetical suffixes Abbreviations, easy Abbreviations, simple Abbreviations, automatic Song lyrics/poems/Mad Libs/phrases Mad Libs Magic 8-ball 99 Bottles of Beer The Name Game (a song) The Old lady swallowed a fly The Twelve Days of Christmas Tokenize Text between Tokenize a string Word break problem Tokenize a string with escaping Split a character string based on change of character Sequences Show ASCII table De Bruijn sequences Self-referential sequences Generate lower case ASCII alphabet
#Nim
Nim
import streams   proc tokenize(s: Stream, sep: static[char] = '|', esc: static[char] = '^'): seq[string] = var buff = "" while not s.atEnd(): let c = s.readChar case c of sep: result.add buff buff = "" of esc: buff.add s.readChar else: buff.add c result.add buff   for i, s in tokenize(newStringStream "one^|uno||three^^^^|four^^^|^cuatro|"): echo i, ":", s