Sorting algorithms/Stooge sort

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Task

Show the Stooge Sort for an array of integers.

The Stooge Sort algorithm is as follows:

algorithm stoogesort(array L, i = 0, j = length(L)-1) if L[j] < L[i] then L[i] ↔ L[j] if j - i > 1 then t := (j - i + 1)/3 stoogesort(L, i , j-t) stoogesort(L, i+t, j ) stoogesort(L, i , j-t) return L

11l

Translation of: Python

F stoogesort(&l, i, j) -> Void I l[j] < l[i] swap(&l[i], &l[j]) I j - i > 1 V t = (j - i + 1) I/ 3 stoogesort(&l, i, j - t) stoogesort(&l, i + t, j) stoogesort(&l, i, j - t) F stooge(&l) R stoogesort(&l, 0, l.len - 1) V data = [1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7] stooge(&data) print(data)

Output:

[-6, -5, -3, -2, 1, 3, 3, 4, 5, 5, 7, 7, 7, 9, 10]

Action!

Action! language does not support recursion. Therefore an iterative approach with a stack has been proposed.

DEFINE MAX_COUNT="100" INT ARRAY stack(MAX_COUNT) INT stackSize PROC PrintArray(INT ARRAY a INT size) INT i Put('[) FOR i=0 TO size-1 DO IF i>0 THEN Put(' ) FI PrintI(a(i)) OD Put(']) PutE() RETURN PROC InitStack() stackSize=0 RETURN BYTE FUNC IsEmpty() IF stackSize=0 THEN RETURN (1) FI RETURN (0) PROC Push(INT low,high) stack(stackSize)=low stackSize==+1 stack(stackSize)=high stackSize==+1 RETURN PROC Pop(INT POINTER low,high) stackSize==-1 high^=stack(stackSize) stackSize==-1 low^=stack(stackSize) RETURN PROC StoogeSort(INT ARRAY a INT size) INT l,h,t,tmp InitStack() Push(0,size-1) WHILE IsEmpty()=0 DO Pop(@l,@h) IF a(l)>a(h) THEN tmp=a(l) a(l)=a(h) a(h)=tmp FI IF h-l>1 THEN t=(h-l+1)/3 Push(l,h-t) Push(l+t,h) Push(l,h-t) FI OD RETURN PROC Test(INT ARRAY a INT size) PrintE("Array before sort:") PrintArray(a,size) StoogeSort(a,size) PrintE("Array after sort:") PrintArray(a,size) PutE() RETURN PROC Main() INT ARRAY a(10)=[1 4 65535 0 3 7 4 8 20 65530], b(21)=[10 9 8 7 6 5 4 3 2 1 0 65535 65534 65533 65532 65531 65530 65529 65528 65527 65526], c(8)=[101 102 103 104 105 106 107 108], d(12)=[1 65535 1 65535 1 65535 1 65535 1 65535 1 65535] Test(a,10) Test(b,21) Test(c,8) Test(d,12) RETURN

Output:

Screenshot from Atari 8-bit computer

Array before sort: [1 4 -1 0 3 7 4 8 20 -6] Array after sort: [-6 -1 0 1 3 4 4 7 8 20] Array before sort: [10 9 8 7 6 5 4 3 2 1 0 -1 -2 -3 -4 -5 -6 -7 -8 -9 -10] Array after sort: [-10 -9 -8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10] Array before sort: [101 102 103 104 105 106 107 108] Array after sort: [101 102 103 104 105 106 107 108] Array before sort: [1 -1 1 -1 1 -1 1 -1 1 -1 1 -1] Array after sort: [-1 -1 -1 -1 -1 -1 1 1 1 1 1 1]

Ada

Using slices and 'First / 'Last removes the need for I / J parameters.

with Ada.Text_IO; procedure Stooge is type Integer_Array is array (Positive range <>) of Integer; procedure Swap (Left, Right : in out Integer) is Temp : Integer := Left; begin Left := Right; Right := Temp; end Swap; procedure Stooge_Sort (List : in out Integer_Array) is T : Natural := List'Length / 3; begin if List (List'Last) < List (List'First) then Swap (List (List'Last), List (List'First)); end if; if List'Length > 2 then Stooge_Sort (List (List'First .. List'Last - T)); Stooge_Sort (List (List'First + T .. List'Last)); Stooge_Sort (List (List'First .. List'Last - T)); end if; end Stooge_Sort; Test_Array : Integer_Array := (1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7); begin Stooge_Sort (Test_Array); for I in Test_Array'Range loop Ada.Text_IO.Put (Integer'Image (Test_Array (I))); if I /= Test_Array'Last then Ada.Text_IO.Put (", "); end if; end loop; Ada.Text_IO.New_Line; end Stooge;

Output:

-6, -5, -3, -2, 1, 3, 3, 4, 5, 5, 7, 7, 7, 9, 10

ALGOL 68

Works with: ALGOL 68G version Any - tested with release 2.8.win32

# swaps the values of the two REF INTs # PRIO =:= = 1; OP =:= = ( REF INT a, b )VOID: ( INT t := a; a := b; b := t ); # returns the array of INTs sorted via the stooge sort algorithm # PROC stooge sort = ( []INT array )[]INT: BEGIN PROC stooge sort segment = ( REF[]INT l, INT i, j )VOID: BEGIN IF l[j] < l[i] THEN l[ i ] =:= l[ j ] FI; IF j - i > 1 THEN INT t := (j - i + 1) OVER 3; stooge sort segment( l, i, j - t ); stooge sort segment( l, i + t, j ); stooge sort segment( l, i, j - t ) FI END # stooge sort segment # ; [ LWB array : UPB array ]INT result := array; stooge sort segment( result, LWB result, UPB result ); result END # stooge sort # ; # test the stooge sort # []INT data = ( 67, -201, 0, 9, 9, 231, 4 ); print( ( "before: ", data, newline, "after: ", stooge sort( data ), newline ) )

Output:

before: +67 -201 +0 +9 +9 +231 +4 after: -201 +0 +4 +9 +9 +67 +231

Arturo

innerStoogeSort: function [a, i, j][  if a\[j] < a\[i] [  t: a\[i]  a\[i]: a\[j]  a\[j]: t  ]  if 1 < j - i [  t: (1 + j - i) / 3  innerStoogeSort a i j-t  innerStoogeSort a i+t j  innerStoogeSort a i j-t  ] ] stoogeSort: function [arr][  result: new arr  innerStoogeSort result 0 dec size result  return result ] print stoogeSort [3 1 2 8 5 7 9 4 6]

Output:

1 2 3 4 5 6 7 8 9

AutoHotkey

StoogeSort(L, i:=1, j:=""){ if !j j := L.MaxIndex() if (L[j] < L[i]){ temp := L[i] L[i] := L[j] L[j] := temp } if (j - i > 1){ t := floor((j - i + 1)/3) StoogeSort(L, i, j-t) StoogeSort(L, i+t, j) StoogeSort(L, i, j-t) } return L }

Examples:

MsgBox % map(StoogeSort([123,51,6,73,3,-12,0])) return map(obj){ for k, v in obj res .= v "," return trim(res, ",") }

Outputs:

-12,0,3,6,51,73,123

BASIC

BBC BASIC

 DIM test%(9)  test%() = 4, 65, 2, -31, 0, 99, 2, 83, 782, 1  PROCstoogesort(test%(), 0, DIM(test%(),1))  FOR i% = 0 TO 9  PRINT test%(i%) ;  NEXT  PRINT  END    DEF PROCstoogesort(l%(), i%, j%)  LOCAL t%  IF l%(j%) < l%(i%) SWAP l%(i%), l%(j%)  IF j% - i% > 1 THEN  t% = (j% - i% + 1)/3  PROCstoogesort(l%(), i%, j%-t%)  PROCstoogesort(l%(), i%+t%, j%)  PROCstoogesort(l%(), i%, j%-t%)  ENDIF  ENDPROC

Output:

 -31 0 1 2 2 4 65 83 99 782

QuickBASIC

Works with: QuickBASIC version 7.1

This might work with older versions of QB, but that is untested. It definitely does not work with QBasic.

DECLARE SUB stoogesort (L() AS LONG, i AS LONG, j AS LONG) RANDOMIZE TIMER CONST arraysize = 10 DIM x(arraysize) AS LONG DIM i AS LONG PRINT "Before: "; FOR i = 0 TO arraysize  x(i) = INT(RND * 100)  PRINT x(i); " "; NEXT PRINT stoogesort x(), 0, arraysize PRINT "After: "; FOR i = 0 TO arraysize  PRINT x(i); " "; NEXT PRINT SUB stoogesort (L() AS LONG, i AS LONG, j AS LONG)  IF L(j) < L(i) THEN SWAP L(i), L(j)  IF (j - i) > 1 THEN  DIM t AS LONG  t = (j - i + 1) / 3  stoogesort L(), i, j - t  stoogesort L(), i + t, j  stoogesort L(), i, j - t  END IF END SUB

Output:

 Before: 15 42 21 50 33 65 40 43 20 25 19 After: 15 19 20 21 33 25 40 42 43 50 65

 Before: 99 21 84 55 32 26 86 27 8 45 11 After: 8 11 21 26 27 32 45 55 84 86 99

 Before: 11 50 11 37 97 94 92 70 92 57 88 After: 11 11 37 50 57 70 88 92 92 94 97

Yabasic

Translation of: FreeBASIC

dim array(15) a = 0 b = arraysize(array(),1) for i = a to b   array(i) = ran(1000) next i print "unsort "; for i = a to b  print array(i) using("####");  if i = b then print ""; else print ", "; : fi next i stoogeSort(array(), a, b) // ordenar el array print "\n sort "; for i = a to b   print array(i) using("####");   if i = b then print ""; else print ", "; : fi next i print end sub stoogeSort(array(), l, r)  if array(r) < array(l) then  temp = array(r)  array(r) = array(l)  array(l) = temp  fi    if r - l > 1 then  t = int((r - l +1) / 3)  stoogeSort(array(), l , r - t)  stoogeSort(array(), l + t, r )  stoogeSort(array(), l , r - t)  fi end sub

BCPL

get "libhdr" let stoogesort(L, i, j) be $( if L!j < L!i then $( let x = L!i L!i := L!j L!j := x $) if j-i>1 then $( let t = (j - i + 1)/3 stoogesort(L, i, j-t) stoogesort(L, i+t, j) stoogesort(L, i, j-t) $) $) let write(s, A, len) be $( writes(s) for i=0 to len-1 do writed(A!i, 4) wrch('*N') $) let start() be $( let array = table 4,65,2,-31,0,99,2,83,782,1 let length = 10 write("Before: ", array, length) stoogesort(array, 0, length-1) write("After: ", array, length) $)

Output:

Before: 4 65 2 -31 0 99 2 83 782 1 After: -31 0 1 2 2 4 65 83 99 782

C

#include <stdio.h> #define SWAP(r,s) do{ t=r; r=s; s=t; } while(0) void StoogeSort(int a[], int i, int j)  {  int t;    if (a[j] < a[i]) SWAP(a[i], a[j]);  if (j - i > 1)  {  t = (j - i + 1) / 3;  StoogeSort(a, i, j - t);  StoogeSort(a, i + t, j);  StoogeSort(a, i, j - t);  } }   int main(int argc, char *argv[]) {  int nums[] = {1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7};  int i, n;    n = sizeof(nums)/sizeof(int);  StoogeSort(nums, 0, n-1);    for(i = 0; i <= n-1; i++)  printf("%5d", nums[i]);    return 0; }

C#

 public static void Sort<T>(List<T> list) where T : IComparable { if (list.Count > 1) { StoogeSort(list, 0, list.Count - 1); } } private static void StoogeSort<T>(List<T> L, int i, int j) where T : IComparable { if (L[j].CompareTo(L[i])<0) { T tmp = L[i]; L[i] = L[j]; L[j] = tmp; } if (j - i > 1) { int t = (j - i + 1) / 3; StoogeSort(L, i, j - t); StoogeSort(L, i + t, j); StoogeSort(L, i, j - t); } }

C++

#include <iostream> #include <time.h> //------------------------------------------------------------------------------ using namespace std; //------------------------------------------------------------------------------ class stooge { public:  void sort( int* arr, int start, int end )  {  if( arr[start] > arr[end - 1] ) swap( arr[start], arr[end - 1] ); int n = end - start; if( n > 2 ) {  n /= 3; sort( arr, start, end - n );  sort( arr, start + n, end ); sort( arr, start, end - n );  }  } }; //------------------------------------------------------------------------------ int main( int argc, char* argv[] ) {  srand( static_cast<unsigned int>( time( NULL ) ) ); stooge s; int a[80], m = 80;   cout << "before:\n";  for( int x = 0; x < m; x++ ) { a[x] = rand() % 40 - 20; cout << a[x] << " "; }  s.sort( a, 0, m ); cout << "\n\nafter:\n";   for( int x = 0; x < m; x++ ) cout << a[x] << " "; cout << "\n\n";   return system( "pause" ); }

Output:

before: 5 -15 11 18 -14 -20 6 -4 -1 -8 12 -18 -12 -4 -10 -8 13 4 0 16 7 -13 -13 -1 11 -9 13 -14 9 -19 -1 14 6 -4 7 -8 -15 -11 -9 3 10 3 -2 -5 12 -8 -2 10 -10 9 14 9 -12 19 -16 -6 -13 -18 -3 -13 -12 8 -8 -10 -16 5 8 -10 -10 6 -14 -20 -16 7 15 11 -19 -18 10 -15 after: -20 -20 -19 -19 -18 -18 -18 -16 -16 -16 -15 -15 -15 -14 -14 -14 -13 -13 -13 -13 -12 -12 -12 -11 -10 -10 -10 -10 -10 -9 -9 -8 -8 -8 -8 -8 -6 -5 -4 -4 -4 -3 -2 -2 -1 -1 -1 0 3 3 4 5 5 6 6 6 7 7 7 8 8 9 9 9 10 10 10 11 11 11 12 12 13 13 14 14 15 16 18 19

Clojure

(defn swap [v x y]   (assoc! v y (v x) x (v y))) (defn stooge-sort  ([v] (persistent! (stooge-sort (transient v) 0 (dec (count v)))))  ([v i j]  (if (> (v i) (v j)) (swap v i j) v)  (if (> (- j i) 1)  (let [t (int (Math/floor (/ (inc (- j i)) 3)))]  (stooge-sort v i (- j t))  (stooge-sort v (+ i t) j)  (stooge-sort v i (- j t))))  v))

COBOL

Works with: GNU Cobol

  >>SOURCE FREE IDENTIFICATION DIVISION. PROGRAM-ID. stooge-sort-test. DATA DIVISION. WORKING-STORAGE SECTION. 01 Arr-Len CONSTANT 7. 01 arr-area VALUE "00004001000020000005000230000000000".  03 arr-elt PIC 9(5) OCCURS Arr-Len TIMES   INDEXED BY arr-idx. PROCEDURE DIVISION.  DISPLAY "Unsorted: " NO ADVANCING   PERFORM VARYING arr-idx FROM 1 BY 1 UNTIL Arr-Len < arr-idx   DISPLAY arr-elt (arr-idx) " " NO ADVANCING   END-PERFORM   DISPLAY SPACE   CALL "stooge-sort" USING arr-area, OMITTED, OMITTED   DISPLAY "Sorted: " NO ADVANCING   PERFORM VARYING arr-idx FROM 1 BY 1 UNTIL Arr-Len < arr-idx   DISPLAY arr-elt (arr-idx) " " NO ADVANCING   END-PERFORM   DISPLAY SPACE  . END PROGRAM stooge-sort-test.   IDENTIFICATION DIVISION. PROGRAM-ID. stooge-sort RECURSIVE. DATA DIVISION. LOCAL-STORAGE SECTION. 01 Arr-Len CONSTANT 7. 01 i  PIC 99 COMP. 01 j  PIC 99 COMP. 01 temp PIC 9(5). 01 t  PIC 99 COMP. LINKAGE SECTION. 01 arr-area.  03 arr-elt PIC 9(5) OCCURS Arr-Len TIMES. 01 i-val PIC 99 COMP. 01 j-val PIC 99 COMP. PROCEDURE DIVISION USING arr-area, OPTIONAL i-val, OPTIONAL j-val.  IF i-val IS OMITTED   MOVE 1 TO i  ELSE   MOVE i-val TO i  END-IF  IF j-val IS OMITTED   MOVE Arr-Len TO j  ELSE   MOVE j-val TO j  END-IF    IF arr-elt (j) < arr-elt (i)   MOVE arr-elt (i) TO temp   MOVE arr-elt (j) TO arr-elt (i)   MOVE temp TO arr-elt (j)  END-IF     IF j - i + 1 >= 3  COMPUTE t = (j - i + 1) / 3  SUBTRACT t FROM j   CALL "stooge-sort" USING arr-area, CONTENT i, j   ADD t TO i, j   CALL "stooge-sort" USING arr-area, CONTENT i, j   SUBTRACT t FROM i, j   CALL "stooge-sort" USING arr-area, CONTENT i, j  END-IF  . END PROGRAM stooge-sort.

Output:

Unsorted: 00004 00100 00200 00005 00023 00000 00000 Sorted: 00000 00000 00004 00005 00023 00100 00200

Common Lisp

(defun stooge-sort (vector &optional (i 0) (j (1- (length vector))))  (when (> (aref vector i) (aref vector j))  (rotatef (aref vector i) (aref vector j)))  (when (> (- j i) 1)  (let ((third (floor (1+ (- j i)) 3)))  (stooge-sort vector i (- j third))  (stooge-sort vector (+ i third) j)  (stooge-sort vector i (- j third))))  vector)

D

import std.stdio, std.algorithm, std.array; void stoogeSort(T)(T[] seq) pure nothrow {  if (seq.back < seq.front)  swap(seq.front, seq.back);  if (seq.length > 2) {  immutable m = seq.length / 3;  seq[0 .. $ - m].stoogeSort();  seq[m .. $].stoogeSort();  seq[0 .. $ - m].stoogeSort();  } } void main() {  auto data = [1, 4, 5, 3, -6, 3, 7, 10, -2, -5];  data.stoogeSort();  writeln(data); }

Output:

[-6, -5, -2, 1, 3, 3, 4, 5, 7, 10]

Delphi

Works with: Delphi version 6.0

Library: SysUtils,StdCtrls

procedure StoogeSort(var L: array of integer; I,J: integer); var T,M: integer; begin if L[j] < L[i] then begin M:=L[I]; L[I]:=L[J]; L[J]:=M; end; if (J - I) > 1 then begin T:=(J - I + 1) div 3; StoogeSort(L, I, J-T); StoogeSort(L, I+T, J); StoogeSort(L, I, J-T); end; end; procedure DoStoogeSort(var L: array of integer); begin StoogeSort(L,0,High(L)); end; var TestData: array [0..9] of integer = (17, 23, 21, 56, 14, 10, 5, 2, 30, 25); function GetArrayStr(IA: array of integer): string; var I: integer; begin Result:='['; for I:=0 to High(IA) do  begin if I>0 then Result:=Result+' ';  Result:=Result+Format('%3d',[IA[I]]);  end; Result:=Result+']'; end; procedure ShowStoogeSort(Memo: TMemo); begin Memo.Lines.Add('Raw Data: '+GetArrayStr(TestData)); DoStoogeSort(TestData); Memo.Lines.Add('Sorted Data: '+GetArrayStr(TestData)); end;

Output:

Raw Data: [ 17 23 21 56 14 10 5 2 30 25] Sorted Data: [ 2 5 10 14 17 21 23 25 30 56] Elapsed Time: 1.158 ms.

EasyLang

proc stsort left right &d[] . if d[left] > d[right] : swap d[left] d[right] if right - left + 1 > 2 t = (right - left + 1) div 3 stsort left right - t d[] stsort left + t right d[] stsort left right - t d[] . . for i = 1 to 100 : d[] &= random 1000 stsort 1 len d[] d[] print d[]

Output:

[ 16 24 26 42 59 66 67 76 77 78 104 108 113 121 127 168 172 185 199 209 219 225 240 247 252 268 288 298 312 329 333 340 359 389 396 402 403 430 446 454 456 461 461 467 480 487 529 542 548 555 561 591 592 612 625 626 652 662 690 692 696 696 722 728 730 734 737 749 768 778 787 791 795 803 808 808 827 827 833 845 852 864 865 866 866 866 869 883 907 912 912 938 957 961 961 982 991 992 993 997 ]

Eiffel

class STOOGE_SORT feature stoogesort (ar: ARRAY[INTEGER]; i,j: INTEGER)  -- Sorted array in ascending order. require ar_not_empty: ar.count >= 0 i_in_range: i>=1 j_in_range: j <= ar.count boundary_set: i<=j local t: REAL_64 third: INTEGER swap: INTEGER do if ar[j]< ar[i] then swap:= ar[i] ar[i]:=ar[j] ar[j]:= swap end if j-i >1 then t:= (j-i+1)/3 third:= t.floor stoogesort(ar, i, j-third) stoogesort(ar, i+third, j) stoogesort(ar, i, j-third) end end end

Test:

class APPLICATION create make feature make do test := <<2, 5, 66, -2, 0, 7>> io.put_string ("%Nunsorted:%N") across test as ar loop io.put_string (ar.item.out + "%T") end create stoogesort stoogesort.stoogesort (test, 1, test.count) io.put_string ("%Nsorted:%N") across test as ar loop io.put_string (ar.item.out + "%T") end end test: ARRAY [INTEGER] stoogesort: STOOGE_SORT end

Output:

unsorted: 2 5 66 -2 0 7 sorted: -2 0 2 5 7 66

Elena

ELENA 6.x :

import extensions; import system'routines; extension op { stoogeSort() = self.stoogeSort(0, self.Length - 1); stoogeSort(IntNumber i, IntNumber j) { if(self[j]<self[i]) { self.exchange(i,j) }; if (j - i > 1) { int t := (j - i + 1) / 3; self.stoogeSort(i,j-t); self.stoogeSort(i+t,j); self.stoogeSort(i,j-t) } } } public program() { var list := new Range(0, 15).selectBy::(n => randomGenerator.nextInt(20)).toArray(); console.printLine("before:", list.asEnumerable()); console.printLine("after:", list.stoogeSort().asEnumerable()) }

Output:

before:0,1,18,17,4,13,18,8,2,10,15,17,11,1,17 after:0,1,1,2,4,8,10,11,13,15,17,17,17,18,18

Elixir

defmodule Sort do  def stooge_sort(list) do  stooge_sort(List.to_tuple(list), 0, length(list)-1) |> Tuple.to_list  end    defp stooge_sort(tuple, i, j) do  if (vj = elem(tuple, j)) < (vi = elem(tuple, i)) do  tuple = put_elem(tuple,i,vj) |> put_elem(j,vi)  end  if j - i > 1 do  t = div(j - i + 1, 3)  tuple  |> stooge_sort(i, j-t)  |> stooge_sort(i+t, j)  |> stooge_sort(i, j-t)  else  tuple  end  end end (for _ <- 1..20, do: :rand.uniform(20)) |> IO.inspect |> Sort.stooge_sort |> IO.inspect

Output:

[18, 8, 19, 19, 17, 17, 1, 5, 17, 9, 13, 6, 7, 19, 1, 6, 11, 20, 17, 12] [1, 1, 5, 6, 6, 7, 8, 9, 11, 12, 13, 17, 17, 17, 17, 18, 19, 19, 19, 20]

EMal

type StoogeSorter fun stoogeSort ← void by List list, int i, int j if list[j] < list[i] do list.swap(i, j) end if j - i + 1 > 2 var t ← (j - i + 1) / 3 stoogeSort(list, i, j - t) stoogeSort(list, i + t, j ) stoogeSort(list, i, j - t) end end fun sort ← <List list|stoogeSort(list, 0, list.length - 1) type Main List sample ← int[1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7] StoogeSorter.sort(sample) writeLine(sample)

Output:

[-6,-5,-3,-2,1,3,3,4,5,5,7,7,7,9,10]

Euphoria

function stooge(sequence s, integer i, integer j) object temp integer t if compare(s[j], s[i]) < 0 then temp = s[i] s[i] = s[j] s[j] = temp end if if j - i > 1 then t = floor((j - i + 1)/3) s = stooge(s, i , j-t) s = stooge(s, i+t, j ) s = stooge(s, i , j-t) end if return s end function function stoogesort(sequence s) return stooge(s,1,length(s)) end function constant s = rand(repeat(1000,10)) ? s ? stoogesort(s)

Output:

{875,616,725,922,463,740,949,476,697,455} {455,463,476,616,697,725,740,875,922,949}

Factor

USING: kernel locals math prettyprint sequences ; IN: rosetta-code.stooge-sort <PRIVATE :: (stooge-sort) ( seq i j -- )  j i [ seq nth ] bi@ < [  j i seq exchange  ] when  j i - 1 > [  j i - 1 + 3 /i :> t  seq i j t - (stooge-sort)  seq i t + j (stooge-sort)  seq i j t - (stooge-sort)  ] when ;  PRIVATE> : stooge-sort ( seq -- sortedseq )  [ clone dup ] [ drop 0 ] [ length 1 - ] tri (stooge-sort) ; : stooge-sort-demo ( -- )  { 1 4 5 3 -6 3 7 10 -2 -5 } stooge-sort . ; MAIN: stooge-sort-demo

Output:

{ -6 -5 -2 1 3 3 4 5 7 10 }

Fortran

Works with: Fortran version 90 and later

program Stooge  implicit none  integer :: i  integer :: array(50) = (/ (i, i = 50, 1, -1) /) ! Reverse sorted array    call Stoogesort(array)  write(*,"(10i5)") array contains recursive subroutine Stoogesort(a)  integer, intent(in out) :: a(:)  integer :: j, t, temp    j = size(a)  if(a(j) < a(1)) then  temp = a(j)  a(j) = a(1)  a(1) = temp  end if  if(j > 2) then  t = j / 3  call Stoogesort(a(1:j-t))  call Stoogesort(a(1+t:j))  call Stoogesort(a(1:j-t))   end if end subroutine end program

FreeBASIC

' version 23-10-2016 ' compile with: fbc -s console Sub stoogesort(s() As Long, l As Long, r As Long)  If s(r) < s(l) Then  Swap s(r), s(l)  End If  If r - l > 1 Then  Var t = (r - l +1) \ 3  stoogesort(s(), l , r - t)  stoogesort(s(), l + t, r )  stoogesort(s(), l , r - t)  End If End Sub ' ------=< MAIN >=------ Dim As Long i, array(-7 To 7) Dim As Long a = LBound(array), b = UBound(array) Randomize Timer For i = a To b : array(i) = i : Next For i = a To b ' little shuffle  Swap array(i), array(Int(Rnd * (b - a +1)) + a) Next Print "unsorted "; For i = a To b : Print Using "####"; array(i); : Next : Print stoogesort(array(), LBound(array), UBound(array)) Print " sorted "; For i = a To b : Print Using "####"; array(i); : Next : Print ' empty keyboard buffer While Inkey <> "" : Wend Print : Print "hit any key to end program" Sleep End

Output:

Unsorted 0 3 -6 2 1 -4 7 5 6 -3 4 -7 -1 -5 -2 After heapsort -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7

Go

package main import "fmt" var a = []int{170, 45, 75, -90, -802, 24, 2, 66} func main() {  fmt.Println("before:", a)  stoogesort(a)  fmt.Println("after: ", a)  fmt.Println("nyuk nyuk nyuk") } func stoogesort(a []int) {  last := len(a) - 1  if a[last] < a[0] {  a[0], a[last] = a[last], a[0]  }  if last > 1 {  t := len(a) / 3  stoogesort(a[:len(a)-t])  stoogesort(a[t:])  stoogesort(a[:len(a)-t])  } }

Haskell

import Data.List import Control.Arrow import Control.Monad insertAt e k = uncurry(++).second ((e:).drop 1). splitAt k swapElems :: [a] -> Int -> Int -> [a] swapElems xs i j = insertAt (xs!!j) i $ insertAt (xs!!i) j xs   stoogeSort [] = [] stoogeSort [x] = [x] stoogeSort xs = doss 0 (length xs - 1) xs doss :: (Ord a) => Int -> Int -> [a] -> [a] doss i j xs  | j-i>1 = doss i (j-t) $ doss (i+t) j $ doss i (j-t) xs'  | otherwise = xs'  where t = (j-i+1)`div`3  xs'  | xs!!j < xs!!i = swapElems xs i j  | otherwise = xs

Example:

*Main> stoogeSort [1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7] [-6,-5,-3,-2,1,3,3,4,5,5,7,7,7,9,10]

Icon and Unicon

procedure main() #: demonstrate various ways to sort a list and string  demosort(stoogesort,[3, 14, 1, 5, 9, 2, 6, 3],"qwerty") end procedure stoogesort(X,op,i,j) #: return sorted list ascending(or descending) local t if /i := 0 then { j := *X op := sortop(op,X) # select how and what we sort } if op(X[j],X[i]) then X[i] :=: X[j] if j - i > 1 then { t := (j - i + 1) / 3 X := stoogesort(X,op,i,j-t) X := stoogesort(X,op,i+t,j) X := stoogesort(X,op,i,j-t) } return X # X must be returned and assigned to sort a string end

Note: This example relies on the supporting procedures 'sortop', and 'demosort' in Bubble Sort. The full demosort exercises the named sort of a list with op = "numeric", "string", ">>" (lexically gt, descending), ">" (numerically gt, descending), a custom comparator, and also a string.

Output:

Abbreviated sample

Sorting Demo using procedure stoogesort on list : [ 3 14 1 5 9 2 6 3 ] with op = &null: [ 1 2 3 3 5 6 9 14 ] (0 ms) ... on string : "qwerty" with op = &null: "eqrtwy" (0 ms)

IS-BASIC

100 PROGRAM "StoogSrt.bas" 110 RANDOMIZE 120 NUMERIC ARRAY(5 TO 16) 130 CALL INIT(ARRAY) 140 CALL WRITE(ARRAY) 150 CALL STOOGESORT(ARRAY,LBOUND(ARRAY),UBOUND(ARRAY)) 160 CALL WRITE(ARRAY) 170 DEF INIT(REF A) 180 FOR I=LBOUND(A) TO UBOUND(A) 190 LET A(I)=RND(99)+1 200 NEXT 210 END DEF 220 DEF WRITE(REF A) 230 FOR I=LBOUND(A) TO UBOUND(A) 240 PRINT A(I); 250 NEXT 260 PRINT 270 END DEF 280 DEF STOOGESORT(REF A,I,J) 290 NUMERIC T 300 IF A(J)<A(I) THEN LET T=A(J):LET A(J)=A(I):LET A(I)=T 310 IF J-I>1 THEN 320 LET T=IP((J-I+1)/3) 330 CALL STOOGESORT(A,I,J-T) 340 CALL STOOGESORT(A,I+T,J) 350 CALL STOOGESORT(A,I,J-T) 360 END IF 370 END DEF

J

swapElems=: |.@:{`[`]} stoogeSort=: 3 : 0  (0,<:#y) stoogeSort y :  if. >/x{y do. y=.x swapElems y end.  if. 1<-~/x do.  t=. <.3%~1+-~/x  (x-0,t) stoogeSort (x+t,0) stoogeSort (x-0,t) stoogeSort y  else. y end. )

Example:

 (,: stoogeSort) ?~13 3 10 8 4 7 12 1 2 11 6 5 9 0 0 1 2 3 4 5 6 7 8 9 10 11 12

Java

import java.util.Arrays; public class Stooge {  public static void main(String[] args) {  int[] nums = {1, 4, 5, 3, -6, 3, 7, 10, -2, -5};  stoogeSort(nums);  System.out.println(Arrays.toString(nums));  }  public static void stoogeSort(int[] L) {  stoogeSort(L, 0, L.length - 1);  }  public static void stoogeSort(int[] L, int i, int j) {  if (L[j] < L[i]) {  int tmp = L[i];  L[i] = L[j];  L[j] = tmp;  }  if (j - i > 1) {  int t = (j - i + 1) / 3;  stoogeSort(L, i, j - t);  stoogeSort(L, i + t, j);  stoogeSort(L, i, j - t);  }  } }

Output:

[-6, -5, -2, 1, 3, 3, 4, 5, 7, 10]

JavaScript

function stoogeSort (array, i, j) {  if (j === undefined) {  j = array.length - 1;  }  if (i === undefined) {  i = 0;  }  if (array[j] < array[i]) {  var aux = array[i];  array[i] = array[j];  array[j] = aux;  }  if (j - i > 1) {  var t = Math.floor((j - i + 1) / 3);  stoogeSort(array, i, j-t);  stoogeSort(array, i+t, j);  stoogeSort(array, i, j-t);  } };

Example:

arr = [9,1,3,10,13,4,2]; stoogeSort(arr); console.log(arr);

Output:

[1, 2, 3, 4, 9, 10, 13]

jq

Works with: jq version 1.4

def stoogesort: def swap(i;j): .[i] as $t | .[i] = .[j] | .[j] = $t; # for efficiency, define an auxiliary function # that takes as input [L, i, j] def ss: .[1] as $i | .[2] as $j | .[0] | if .[$j] < .[$i] then swap($i;$j) else . end | if $j - $i > 1 then (($j - $i + 1) / 3 | floor) as $t | [., $i, $j-$t] | ss | [., $i+$t, $j] | ss | [., $i, $j-$t] | ss else . end; [., 0, length-1] | ss;

Example

([], [1], [1,2], [1,3,2,4], [1,4,5,3,-6,3,7,10,-2,-5] ) | stoogesort

Output:

$ jq -c -n -f stooge_sort.jq [] [1] [1,2] [1,2,3,4] [-6,-5,-2,1,3,3,4,5,7,10]

Julia

Translation of: Matlab

function stoogesort!(a::Array, i::Int=1, j::Int=length(a))  if a[j] < a[i]  a[[i, j]] = a[[j, i]];  end  if (j - i) > 1  t = (j - i + 1) ÷ 3  a = stoogesort!(a, i, j - t)  a = stoogesort!(a, i + t, j)  a = stoogesort!(a, i, j - t)  end  return a end x = randn(10) @show x stoogesort!(x)

Output:

x = [0.222881, -1.06902, -1.07703, 0.466872, 1.52261, -0.25279, -1.72147, -0.217577, -0.556917, 2.13601] stoogesort!(x) = [-1.72147, -1.07703, -1.06902, -0.556917, -0.25279, -0.217577, 0.222881, 0.466872, 1.52261, 2.13601]

Kotlin

// version 1.1.0 fun stoogeSort(a: IntArray, i: Int, j: Int) {  if (a[j] < a[i]) {  val temp = a[j]  a[j] = a[i]  a[i] = temp  }  if (j - i > 1) {  val t = (j - i + 1) / 3  stoogeSort(a, i, j - t)  stoogeSort(a, i + t, j)  stoogeSort(a, i, j - t)  } } fun main(args: Array<String>) {  val a = intArrayOf(100, 2, 56, 200, -52, 3, 99, 33, 177, -199)  println("Original : ${a.asList()}")  stoogeSort(a, 0, a.size - 1)  println("Sorted  : ${a.asList()}")  }

Output:

Original : [100, 2, 56, 200, -52, 3, 99, 33, 177, -199] Sorted  : [-199, -52, 2, 3, 33, 56, 99, 100, 177, 200]

Lambdatalk

{def stoogesort  {def stoogesort.r  {lambda {:a :i :j}  {let { {:a {if {< {A.get :j :a} {A.get :i :a}}   then {A.swap! :i :j :a}   else :a}}  {:i :i} {:j :j}  {:t {floor {/ {+ :j {- :i} 1} 3}}}  } {if {> {- :j :i} 1}  then {stoogesort.r :a :i {- :j :t}}  {stoogesort.r :a {+ :i :t} :j}  {stoogesort.r :a :i {- :j :t}}  else }} }}  {lambda {:a}  {stoogesort.r :a 0 {- {A.length :a} 1}} :a}}  -> stoogesort {def A {A.new 9 1 3 10 13 4 2}}  -> A {stoogesort {A}} -> [1,2,3,4,9,10,13]

Lua

An example using a Y combinator for anonymous recursion and made generic with an optional predicate parameter.

local Y = function (f)  return (function(x) return x(x) end)(function(x) return f(function(...) return x(x)(...) end) end) end function stoogesort(L, pred)  pred = pred or function(a,b) return a < b end  Y(function(recurse)  return function(i,j)  if pred(L[j], L[i]) then  L[j],L[i] = L[i],L[j]  end  if j - i > 1 then  local t = math.floor((j - i + 1)/3)  recurse(i,j-t)  recurse(i+t,j)  recurse(i,j-t)  end  end  end)(1,#L)    return L end print(unpack(stoogesort{9,7,8,5,6,3,4,2,1,0}))

Maple

swap := proc(arr, a, b) local temp := arr[a]; arr[a] := arr[b]; arr[b] := temp; end proc: stoogesort:= proc(arr, start_index, end_index) local cur; if (arr[end_index] < arr[start_index]) then swap(arr, start_index, end_index); end if;  if end_index - start_index > 1 then cur := trunc((end_index - start_index + 1)/3); stoogesort(arr, start_index, end_index - cur); stoogesort(arr, start_index + cur, end_index); stoogesort(arr, start_index, end_index - cur); end if;  return arr; end proc: arr := Array([4, 2, 6, 1, 3, 7, 9, 5, 8]): stoogesort(arr, 1, numelems(arr));

Output:

[1, 2, 3, 4, 5, 6, 7, 8, 9]

Mathematica /Wolfram Language

stoogeSort[lst_, I_, J_] := Module[{i = I, j = J, list = lst},  If[list[[j]] < list[[i]], list[[{i,j}]] = list[[{j,i}]];]   If[(j-i) > 1, t = Round[(j-i+1)/3];  list=stoogeSort[list,i,j-t];  list=stoogeSort[list,i+t,j];  list=stoogeSort[list,i,j-t];];  list ]

Output:

stoogeSort[{3,2,9,6,8},1,5] {2,3,6,8,9}

MATLAB / Octave

%Required inputs: %i = 1 %j = length(list) % function list = stoogeSort(list,i,j)  if list(j) < list(i)  list([i j]) = list([j i]);  end    if (j - i) > 1  t = round((j-i+1)/3);  list = stoogeSort(list,i,j-t);  list = stoogeSort(list,i+t,j);  list = stoogeSort(list,i,j-t);  end end

Output:

>> stoogeSort([1 -6 4 -9],1,4) ans =  -9 -6 1 4

Maxima

stoogesort(list, i, j) := block( if(list[j]<list[i]) then block(a: list[j], b: list[i], list[i]: a, list[j]:b), if(j-i>1) then block(  t: floor((j-i+1)/3),  stoogesort(list, i, j-t),  stoogesort(list, i+t, j),  stoogesort(list, i, j-t)), list)$ test_list: makelist(random(21),20); stooge(list) := stoogesort(list, 1, length(list))$ stooge(test_list);

Output:

[8,10,2,16,6,14,16,6,16,20,18,0,1,2,15,13,7,20,16,3] [0,1,2,2,3,6,6,7,8,10,13,14,15,16,16,16,16,18,20,20]

MAXScript

fn stoogeSort arr i: j: = (	if i == unsupplied do i = 1	if j == unsupplied do j = arr.count	if arr[j] < arr[i] do	(	swap arr[j] arr[i]	)	if j - i > 1 do	(	local t = (j - i+1)/3	arr = stoogeSort arr i:i j:(j-t)	arr = stoogeSort arr i:(i+t) j:j	arr = stoogeSort arr i:i j:(j-t)	)	return arr )

Output:

a = for i in 1 to 15 collect random 1 20 #(10, 2, 1, 19, 18, 20, 18, 5, 13, 2, 13, 9, 7, 10, 6) stoogeSort a #(1, 2, 2, 5, 6, 7, 9, 10, 10, 13, 13, 18, 18, 19, 20)

NetRexx

/* NetRexx */ options replace format comments java crossref savelog symbols binary iList = [int 1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7] sList = Arrays.copyOf(iList, iList.length) sList = stoogeSort(sList) lists = [iList, sList] loop ln = 0 to lists.length - 1  cl = lists[ln]  rpt = Rexx('')  loop ct = 0 to cl.length - 1  rpt = rpt cl[ct]  end ct  say '['rpt.strip().changestr(' ', ',')']'  end ln return method stoogeSort(L_ = int[], i_ = 0, j_ = L_.length - 1) public static returns int[]  if L_[j_] < L_[i_] then do  Lt = L_[i_]  L_[i_] = L_[j_]  L_[j_] = Lt  end  if j_ - i_ > 1 then do  t_ = (j_ - i_ + 1) % 3  L_ = stoogeSort(L_, i_, j_ - t_)  L_ = stoogeSort(L_, i_ + t_, j_)  L_ = stoogeSort(L_, i_, j_ - t_)  end  return L_

Output:

[1,4,5,3,-6,3,7,10,-2,-5,7,5,9,-3,7] [-6,-5,-3,-2,1,3,3,4,5,5,7,7,7,9,10]

Nim

proc stoogeSort[T](a: var openarray[T], i, j: int) =  if a[j] < a[i]: swap a[i], a[j]  if j - i > 1:  let t = (j - i + 1) div 3  stoogeSort(a, i, j - t)  stoogeSort(a, i + t, j)  stoogeSort(a, i, j - t) var a = @[4, 65, 2, -31, 0, 99, 2, 83, 782] stoogeSort a, 0, a.high echo a

Output:

@[-31, 0, 2, 2, 4, 65, 83, 99, 782]

Objeck

bundle Default { class Stooge { function : Main(args : String[]) ~ Nil { nums := [1, 4, 5, 3, -6, 3, 7, 10, -2, -5]; StoogeSort(nums); each(i : nums) { IO.Console->Print(nums[i])->Print(","); }; IO.Console->PrintLine(); } function : native : StoogeSort(l : Int[]) ~ Nil { StoogeSort(l, 0, l->Size() - 1); } function : native : StoogeSort(l : Int[], i : Int, j : Int) ~ Nil { if(l[j] < l[i]) { tmp := l[i]; l[i] := l[j]; l[j] := tmp; }; if(j - i > 1) { t := (j - i + 1) / 3; StoogeSort(l, i, j - t); StoogeSort(l, i + t, j); StoogeSort(l, i, j - t); }; } } }

OCaml

let swap ar i j = let tmp = ar.(i) in ar.(i) <- ar.(j); ar.(j) <- tmp let stoogesort ar = let rec aux i j = if ar.(j) < ar.(i) then swap ar i j else if j - i > 1 then begin let t = (j - i + 1) / 3 in aux (i) (j-t); aux (i+t) (j); aux (i) (j-t); end in aux 0 (Array.length ar - 1)

testing:

let () = let ar = [| 3; 1; 7; 2; 6; 5; 4; 9; 8 |] in stoogesort ar; Array.iter (Printf.printf " %d") ar; print_newline()

ooRexx

Translation of: NetRexx

/* Rexx */ call demo return exit -- ----------------------------------------------------------------------------- -- Stooge sort implementation -- ----------------------------------------------------------------------------- ::routine stoogeSort  use arg rL_, i_ = 0, j_ = .nil  if j_ = .nil then j_ = rL_~items() - 1  if rL_~get(j_) < rL_~get(i_) then do  Lt = rL_~get(i_)  rL_~set(i_, rL_~get(j_))  rL_~set(j_, Lt)  end  if j_ - i_ > 1 then do  t_ = (j_ - i_ + 1) % 3  rL_ = stoogeSort(rL_, i_, j_ - t_)  rL_ = stoogeSort(rL_, i_ + t_, j_)  rL_ = stoogeSort(rL_, i_, j_ - t_)  end  return rL_ -- ----------------------------------------------------------------------------- -- Demonstrate the implementation -- ----------------------------------------------------------------------------- ::routine demo  iList = .nlist~of(1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7)  sList = iList~copy()  placesList = .nlist~of( -  "UK London", "US New York", "US Boston", "US Washington" -  , "UK Washington", "US Birmingham", "UK Birmingham", "UK Boston" -  )  sList = stoogeSort(sList)  sortedList = stoogeSort(placesList~copy())  iLists = .list~of(iList, sList)  loop ln = 0 to iLists~items() - 1  icl = iLists[ln]  rpt = ''  loop ct = 0 to icl~items() - 1  rpt = rpt icl[ct]  end ct  say '['rpt~strip()~changestr(' ', ',')']'  end ln  say  sLists = .list~of(placesList, sortedList)  loop ln = 0 to sLists~items() - 1  scl = sLists[ln]  loop ct = 0 to scl~items() - 1  say right(ct + 1, 3)':' scl[ct]  end ct  say  end ln  return -- ----------------------------------------------------------------------------- -- Helper class. Map get and set methods for easier conversion from java.util.List -- ----------------------------------------------------------------------------- ::class NList mixinclass List public -- Map get() to at() ::method get  use arg ix  return self~at(ix) -- Map set() to put() ::method set  use arg ix, item  self~put(item, ix)  return

Output:

[1,4,5,3,-6,3,7,10,-2,-5,7,5,9,-3,7] [-6,-5,-3,-2,1,3,3,4,5,5,7,7,7,9,10] 1: UK London 2: US New York 3: US Boston 4: US Washington 5: UK Washington 6: US Birmingham 7: UK Birmingham 8: UK Boston 1: UK Birmingham 2: UK Boston 3: UK London 4: UK Washington 5: US Birmingham 6: US Boston 7: US New York 8: US Washington

Oz

declare proc {StoogeSort Arr} proc {Swap I J} Tmp = Arr.I in Arr.I := Arr.J Arr.J := Tmp end proc {Sort I J} Size = J-I+1 in if Arr.J < Arr.I then {Swap I J} end if Size >= 3 then Third = Size div 3 in {Sort I J-Third} {Sort I+Third J} {Sort I J-Third} end end in {Sort {Array.low Arr} {Array.high Arr}} end Arr = {Tuple.toArray unit(1 4 5 3 ~6 3 7 10 ~2 ~5 7 5 9 ~3 7)} in {System.printInfo "\nUnsorted: "} for I in {Array.low Arr}..{Array.high Arr} do {System.printInfo Arr.I#", "} end {StoogeSort Arr} {System.printInfo "\nSorted  : "} for I in {Array.low Arr}..{Array.high Arr} do {System.printInfo Arr.I#", "} end

Output:

Unsorted: 1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7, Sorted  : -6, -5, -3, -2, 1, 3, 3, 4, 5, 5, 7, 7, 7, 9, 10,

PARI/GP

stoogeSort(v)={ local(v=v); \\ Give children access to v ss(1,#v); \\ Sort v } ss(i,j)={ my(t); if(v[j]<v[i], t=v[i]; v[i]=v[j]; v[j]=t ); if(j-i > 1, t=(1+j-i)\3; ss(i,j-t); ss(i+t,j); ss(i,j-t) ) };

Pascal

program StoogeSortDemo;   type  TIntArray = array of integer; procedure stoogeSort(var m: TIntArray; i, j: integer);  var  t, temp: integer;  begin  if m[j] < m[i] then  begin  temp := m[j];  m[j] := m[i];  m[i] := temp;  end;  if j - i > 1 then  begin  t := (j - i + 1) div 3;  stoogesort(m, i, j-t);  stoogesort(m, i+t, j);  stoogesort(m, i, j-t);  end;  end; var  data: TIntArray;  i: integer; begin  setlength(data, 8);  Randomize;  writeln('The data before sorting:');  for i := low(data) to high(data) do  begin  data[i] := Random(high(data));  write(data[i]:4);  end;  writeln;  stoogeSort(data, low(data), high(data));  writeln('The data after sorting:');  for i := low(data) to high(data) do  begin  write(data[i]:4);  end;  writeln; end.

Output:

./StoogeSort The data before sorting: 6 1 2 1 5 2 1 5 The data after sorting: 1 1 1 2 2 5 5 6

Perl

sub stooge {  use integer;  my ($x, $i, $j) = @_;  $i //= 0;  $j //= $#$x;  if ( $x->[$j] < $x->[$i] ) {  @$x[$i, $j] = @$x[$j, $i];  }  if ( $j - $i > 1 ) {  my $t = ($j - $i + 1) / 3;  stooge( $x, $i, $j - $t );  stooge( $x, $i + $t, $j );   stooge( $x, $i, $j - $t );  } } my @a = map (int rand(100), 1 .. 10); print "Before @a\n"; stooge(\@a); print "After @a\n";

Phix

with javascript_semantics function stoogesort(sequence s, integer i=1, j=length(s))  if s[j]<s[i] then  {s[i],s[j]} = {s[j],s[i]}  end if  if j-i>1 then  integer t = floor((j-i+1)/3)  s = stoogesort(s,i, j-t)  s = stoogesort(s,i+t,j )  s = stoogesort(s,i, j-t)  end if  return s end function ?stoogesort(shuffle(tagset(10)))

Output:

{1,2,3,4,5,6,7,8,9,10}

PHP

function stoogeSort(&$arr, $i, $j) { if($arr[$j] < $arr[$i]) { list($arr[$j],$arr[$i]) = array($arr[$i], $arr[$j]); } if(($j - $i) > 1) { $t = ($j - $i + 1) / 3; stoogesort($arr, $i, $j - $t); stoogesort($arr, $i + $t, $j); stoogesort($arr, $i, $j - $t); } }

PicoLisp

(de stoogeSort (L N) (default N (length L)) (let P (nth L N) (when (> (car L) (car P)) (xchg L P) ) ) (when (> N 2) (let D (/ N 3) (stoogeSort L (- N D)) (stoogeSort (nth L (inc D)) (- N D)) (stoogeSort L (- N D)) ) ) L )

Test:

: (apply < (stoogeSort (make (do 100 (link (rand)))))) -> T

PL/I

stoogesort: procedure (L) recursive; /* 16 August 2010 */ declare L(*) fixed binary; declare (i, j, t, temp) fixed binary; j = hbound(L,1); do i = lbound(L, 1) to j; if L(j) < L(i) then do; temp = L(i); L(i) = L(j); L(j) = temp; end; if j - i > 1 then do; t = (j - i + 1)/3; call stoogesort(L, i , j-t); call stoogesort(L, i+t, j ); call stoogesort(L, i , j-t); end; end; end stoogesort;

Pluto

Translation of: Wren

local function stooge_sort(a, i, j)  if a[j] < a[i] then  a[i], a[j] = a[j], a[i]  end  if j - i > 1 then  local t = (j - i + 1) // 3  stooge_sort(a, i, j - t)  stooge_sort(a, i + t, j)  stooge_sort(a, i, j - t)  end end local array = { {4, 65, 2, -31, 0, 99, 2, 83, 782, 1}, {7, 5, 2, 6, 1, 4, 2, 6, 3} } for array as a do  print($"Before: \{{a:concat(", ")}}")  stooge_sort(a, 1, #a)  print($"After : \{{a:concat(", ")}}")  print() end

Output:

Before: {4, 65, 2, -31, 0, 99, 2, 83, 782, 1} After : {-31, 0, 1, 2, 2, 4, 65, 83, 99, 782} Before: {7, 5, 2, 6, 1, 4, 2, 6, 3} After : {1, 2, 2, 3, 4, 5, 6, 6, 7}

PowerBASIC

PowerBASIC for DOS can use the BASIC code above, by removing CONST and changing all instances of arraysize to %arraysize (note the percent sign).

Works with: PowerBASIC for Windows

Works with: PowerBASIC Console Compiler

This version is closely based on the BASIC code above.

%arraysize = 10 SUB stoogesort (L() AS LONG, i AS LONG, j AS LONG) IF L(j) < L(i) THEN SWAP L(i), L(j) IF (j - i) > 1 THEN DIM t AS LONG t = (j - i + 1) / 3 stoogesort L(), i, j - t stoogesort L(), i + t, j stoogesort L(), i, j - t END IF END SUB FUNCTION PBMAIN () AS LONG RANDOMIZE TIMER DIM x(%arraysize) AS LONG DIM i AS LONG, s AS STRING s = "Before: " FOR i = 0 TO %arraysize x(i) = INT(RND * 100) s = s & STR$(x(i)) & " " NEXT stoogesort x(), 0, %arraysize #IF %DEF(%PB_CC32) PRINT s s = "" #ELSE s = s & $CRLF #ENDIF s = s & "After: " FOR i = 0 TO %arraysize s = s & STR$(x(i)) & " " NEXT  ? s END FUNCTION

Output:

Before: 88 32 82 88 0 82 65 87 40 1 69 After: 0 1 32 40 65 69 82 82 87 88 88 Before: 60 64 95 11 52 26 7 4 51 67 47 After: 4 7 11 26 47 51 52 60 64 67 95 Before: 47 88 67 76 60 66 69 86 92 41 6 After: 6 41 47 60 66 67 69 76 88 86 92

PowerShell

Function StoogeSort( [Int32[]] $L ) { $i = 0 $j = $L.length-1 if( $L[$j] -lt $L[$i] ) { $L[$i] = $L[$i] -bxor $L[$j] $L[$j] = $L[$i] -bxor $L[$j] $L[$i] = $L[$i] -bxor $L[$j] } if( $j -gt 1 ) { $t = [int] ( ( $j + 1 ) / 3 ) $k = $j - $t + 1 [Array]::Copy( [Int32[]] ( StoogeSort( $L[0..( $j - $t ) ] ) ), $L, $k ) [Array]::ConstrainedCopy( [Int32[]] ( StoogeSort( $L[$t..$j ] ) ), 0, $L, $t, $k ) [Array]::Copy( [Int32[]] ( StoogeSort( $L[0..( $j - $t ) ] ) ), $L, $k ) } $L } StoogeSort 9, 7, 5, 3, 1, 2, 4, 6, 8

PureBasic

Procedure Stooge_Sort(Array L.i(1), i=0 , j=0)  If j=0  j=ArraySize(L())  EndIf  If L(i)>L(j)  Swap L(i), L(j)  EndIf  If j-i>1  Protected t=(j-i+1)/3  Stooge_Sort(L(), i, j-t)  Stooge_Sort(L(), i+t, j )  Stooge_Sort(L(), i, j-t)  EndIf EndProcedure

Implementation may be as

Define AmountOfPosts=(?Stop_Data-?Start_data)/SizeOf(Integer) Dim Xyz.i(AmountOfPosts) CopyMemory(?Start_data, @Xyz(), ?Stop_Data-?Start_data) Stooge_Sort(Xyz()) For i=0 To ArraySize(Xyz())  Debug Xyz(i) Next i DataSection  Start_data:  Data.i 1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7  Stop_Data: EndDataSection

Python

>>> data = [1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7] >>> def stoogesort(L, i=0, j=None): if j is None: j = len(L) - 1 if L[j] < L[i]: L[i], L[j] = L[j], L[i] if j - i > 1: t = (j - i + 1) // 3 stoogesort(L, i , j-t) stoogesort(L, i+t, j ) stoogesort(L, i , j-t) return L >>> stoogesort(data) [-6, -5, -3, -2, 1, 3, 3, 4, 5, 5, 7, 7, 7, 9, 10]

This alternate solution uses a wrapper function to compute the initial value of j rather than detecting the sentinel value None.

>>> def stoogesort(L, i, j): if L[j] < L[i]: L[i], L[j] = L[j], L[i] if j - i > 1: t = (j - i + 1) // 3 stoogesort(L, i , j-t) stoogesort(L, i+t, j ) stoogesort(L, i , j-t) return L >>> def stooge(L): return stoogesort(L, 0, len(L) - 1) >>> data = [1, 4, 5, 3, -6, 3, 7, 10, -2, -5, 7, 5, 9, -3, 7] >>> stooge(data) [-6, -5, -3, -2, 1, 3, 3, 4, 5, 5, 7, 7, 7, 9, 10]

Quackery

 [ 2 * 3 /mod 0 > + ] is twothirds ( n --> n ) [ dup 0 peek over -1 peek 2dup > iff [ rot 0 poke -1 poke ] else 2drop ] is swapends ( [ --> [ ) [ swapends dup size 3 < if done dup size twothirds split swap recurse swap join dup size 3 / split recurse join dup size twothirds split swap recurse swap join ] is stoogesort ( [ --> [ ) [] 33 times [ 90 random 10 + join ] dup echo cr stoogesort echo

Output:

[ 32 45 68 88 88 89 45 20 86 74 31 91 24 77 87 91 89 76 41 76 84 14 99 72 98 73 79 11 22 75 66 27 34 ] [ 11 14 20 22 24 27 31 32 34 41 45 45 66 68 72 73 74 75 76 76 77 79 84 86 87 88 88 89 89 91 91 98 99 ]

R

stoogesort = function(vect) { i <- 1 j <- length(vect) if(vect[j] < vect[i]) vect[c(j, i)] <- vect[c(i, j)] if(j - i > 1) { t <- (j - i + 1) %/% 3 vect[i:(j - t)] <- stoogesort(vect[i:(j - t)]) vect[(i + t):j] <- stoogesort(vect[(i + t):j]) vect[i:(j - t)] <- stoogesort(vect[i:(j - t)]) } vect } v <- print(sample(21, 20)) stoogesort(v)

Output:

 [1] 13 5 20 16 11 19 17 7 9 14 21 18 2 10 1 6 8 4 15 12 [1] 1 2 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Racket

#lang racket (define (stooge-sort xs [i 0] [j (- (vector-length xs) 1)])  (define (x i) (vector-ref xs i))  (define (x! i v) (vector-set! xs i v))  (define (swap! i j) (define t (x i)) (x! i (x j)) (x! j t))  (when (> (x i) (x j)) (swap! i j))  (when (> (- j i) 1)  (define t (quotient (+ j (- i) 1) 3))  (stooge-sort xs i (- j t))  (stooge-sort xs (+ i t) j)  (stooge-sort xs i (- j t)))  xs)

Raku

(formerly Perl 6)

sub stoogesort( @L, $i = 0, $j = @L.end ) {  @L[$j,$i] = @L[$i,$j] if @L[$i] > @L[$j];   my $interval = $j - $i;   if $interval > 1 {  my $t = ( $interval + 1 ) div 3;  stoogesort( @L, $i , $j-$t );  stoogesort( @L, $i+$t, $j );  stoogesort( @L, $i , $j-$t );  }  return @L; }  my @L = 1, 4, 5, 3, -6, 3, 7, 10, -2, -5;  stoogesort(@L).Str.say;

REXX

This REXX example starts an array at element zero (but any integer could be used); a zero-
based index was used because the algorithm shown in the Rosetta Code task used zero.

/*REXX program sorts an integer array @. [the first element starts at index zero].*/ parse arg N . /*obtain an optional argument from C.L.*/ if N=='' | N=="," then N=19 /*Not specified? Then use the default.*/ call gen@ /*generate a type of scattered array. */ call show 'before sort' /*show the before array elements. */ say copies('▒', wN+wV+ 50) /*show a separator line (between shows)*/ call stoogeSort 0, N /*invoke the Stooge Sort. */ call show ' after sort' /*show the after array elements. */ exit /*stick a fork in it, we're all done. */ /*──────────────────────────────────────────────────────────────────────────────────────*/ gen@: wV= 0; do k=0 to N; @.k= k*2 + k*-1**k; if @.k//7==0 then @.k= -100 - k  wV= max(wV, length(@.k) ); end; wN=length(N); return /*──────────────────────────────────────────────────────────────────────────────────────*/ show: do j=0 to N; say right('element',22) right(j,wN) arg(1)":" right(@.j,wV); end;return /*──────────────────────────────────────────────────────────────────────────────────────*/ stoogeSort: procedure expose @.; parse arg i,j /*sort from I ───► J. */  if @.j<@.i then parse value @.i @.j with @.j @.i /*swap @.i with @.j */  if j-i>1 then do; t=(j-i+1) % 3 /*%: integer division.*/  call stoogeSort i , j-t /*invoke recursively. */  call stoogeSort i+t, j /* " " */  call stoogeSort i , j-t /* " " */  end  return

output when using the default (internal generated) inputs:

(Shown at three-quarter size.)

 element 0 before sort: -100 element 1 before sort: 1 element 2 before sort: 6 element 3 before sort: 3 element 4 before sort: 12 element 5 before sort: 5 element 6 before sort: 18 element 7 before sort: -107 element 8 before sort: 24 element 9 before sort: 9 element 10 before sort: 30 element 11 before sort: 11 element 12 before sort: 36 element 13 before sort: 13 element 14 before sort: -114 element 15 before sort: 15 element 16 before sort: 48 element 17 before sort: 17 element 18 before sort: 54 element 19 before sort: 19 ▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒▒ element 0 after sort: -114 element 1 after sort: -107 element 2 after sort: -100 element 3 after sort: 1 element 4 after sort: 3 element 5 after sort: 5 element 6 after sort: 6 element 7 after sort: 9 element 8 after sort: 11 element 9 after sort: 12 element 10 after sort: 13 element 11 after sort: 15 element 12 after sort: 17 element 13 after sort: 18 element 14 after sort: 19 element 15 after sort: 24 element 16 after sort: 30 element 17 after sort: 36 element 18 after sort: 48 element 19 after sort: 54

Ring

test = [4, 65, 2, -31, 0, 99, 2, 83, 782, 1] stoogeSort(test, 1, len(test)) for i = 1 to 10 see "" + test[i] + " " next see nl func stoogeSort list, i, j if list[j] < list[i] temp = list[i] list[i] = list[j] list[j] = temp ok if j - i > 1 t = (j - i + 1)/3 stoogeSort(list, i, j-t) stoogeSort(list, i+t, j) stoogeSort(list, i, j-t) ok return list

Output:

-31 0 1 2 2 4 65 83 99 782

RPL

« 0 → start end t « DUP start GET OVER end GET IF DUP2 > THEN ROT start ROT PUT end ROT PUT ELSE DROP2 END IF end start - 2 ≥ THEN end start - 1 + 3 / FLOOR 't' STO start end t - STOOGESORT start t + end STOOGESORT start end t - STOOGESORT END » » 'STOOGESORT' STO @ ( { } start end → { } )

{ 1 4 5 3 -6 3 7 10 -2 -5 7 5 9 -3 7 } 1 OVER SIZE STOOGESORT

Output:

1: { -6 - 5 -3 -2 1 3 3 4 5 5 7 7 7 9 10 }

Stooge sort is 436 times slower than the built-in SORT function on an HP-50g.

Ruby

class Array  def stoogesort  self.dup.stoogesort!  end  def stoogesort!(i = 0, j = self.length-1)  if self[j] < self[i]  self[i], self[j] = self[j], self[i]  end  if j - i > 1  t = (j - i + 1)/3  stoogesort!(i, j-t)  stoogesort!(i+t, j)  stoogesort!(i, j-t)  end  self  end end p [1,4,5,3,-6,3,7,10,-2,-5].stoogesort

Output:

[-6, -5, -2, 1, 3, 3, 4, 5, 7, 10]

Rust

fn stoogesort<E>(a: &mut [E])  where E: PartialOrd {  let len = a.len();  if a.first().unwrap() > a.last().unwrap() {  a.swap(0, len - 1);  }  if len - 1 > 1 {  let t = len / 3;  stoogesort(&mut a[..len - 1]);  stoogesort(&mut a[t..]);  stoogesort(&mut a[..len - 1]);  } } fn main() {  let mut numbers = vec![1_i32, 9, 4, 7, 6, 5, 3, 2, 8];  println!("Before: {:?}", &numbers);  stoogesort(&mut numbers);  println!("After: {:?}", &numbers); }

Scala

object StoogeSort extends App {  def stoogeSort(a: Array[Int], i: Int, j: Int) {  if (a(j) < a(i)) {  val temp = a(j)  a(j) = a(i)  a(i) = temp  }  if (j - i > 1) {  val t = (j - i + 1) / 3  stoogeSort(a, i, j - t)  stoogeSort(a, i + t, j)  stoogeSort(a, i, j - t)  }  }  val a = Array(100, 2, 56, 200, -52, 3, 99, 33, 177, -199)  println(s"Original : ${a.mkString(", ")}")  stoogeSort(a, 0, a.length - 1)  println(s"Sorted  : ${a.mkString(", ")}") }

See it running in your browser by Scastie (JVM).

Sidef

func stooge(x, i, j) {  if (x[j] < x[i]) {  x.swap(i, j)  }  if (j-i > 1) {  var t = ((j - i + 1) / 3)  stooge(x, i, j - t)  stooge(x, i + t, j )  stooge(x, i, j - t)  } } var a = 10.of { 100.irand } say "Before #{a}" stooge(a, 0, a.end) say "After #{a}"

Smalltalk

Works with: GNU Smalltalk

OrderedCollection extend [ stoogeSortFrom: i to: j [	(self at: j) < (self at: i) ifTrue: [ self swapElement: i with: j ]. j - i > 1 ifTrue: [ |t| t := (j - i + 1)//3. self stoogeSortFrom: i to: (j-t). self stoogeSortFrom: (i+t) to: j. self stoogeSortFrom: i to: (j-t) ] ] stoogeSort [ self stoogeSortFrom: 1 to: (self size) ] swapElement: i with: j [ |t| t := self at: i. self at: i put: (self at: j). self at: j put: t ] ]. |test| test := #( 1 4 5 3 -6 3 7 10 -2 -5) asOrderedCollection. test stoogeSort. test printNl.

Here is a "functional" variation (a 1:1 adaption of the original algorithm):

stoogesort := [:L :i :j | (L at:i) > (L at:j) ifTrue:[ L swap:i with:j ]. (j - i + 1) > 2 ifTrue:[ t := ((j - i + 1) / 3) floor. stoogesort value:L value:i value:j-t. stoogesort value:L value:i+t value:j. stoogesort value:L value:i value:j-t. ]. ]. a := #(1 4 5 3 -6 3 7 10 -2 -5 7 5 9 -3 7) copy. stoogesort value:a value:1 value:a size. Transcript showCR:a

Output:

#(-6 -5 -3 -2 1 3 3 4 5 5 7 7 7 9 10)

Swift

func stoogeSort(inout arr:[Int], _ i:Int = 0, var _ j:Int = -1) {  if j == -1 {  j = arr.count - 1  }    if arr[i] > arr[j] {  swap(&arr[i], &arr[j])  }    if j - i > 1 {  let t = (j - i + 1) / 3  stoogeSort(&arr, i, j - t)  stoogeSort(&arr, i + t, j)  stoogeSort(&arr, i, j - t)  } } var a = [-4, 2, 5, 2, 3, -2, 1, 100, 20] stoogeSort(&a) println(a)

Output:

[-4, -2, 1, 2, 2, 3, 5, 20, 100]

Tcl

Works with: Tcl version 8.5

package require Tcl 8.5 proc stoogesort {L {i 0} {j -42}} {  if {$j == -42} {# Magic marker  set j [expr {[llength $L]-1}]  }  set Li [lindex $L $i]  set Lj [lindex $L $j]  if {$Lj < $Li} {  lset L $i $Lj  lset L $j $Li  }   if {$j-$i > 1} {  set t [expr {($j-$i+1)/3}]  set L [stoogesort $L $i [expr {$j-$t}]]  set L [stoogesort $L [expr {$i+$t}] $j]  set L [stoogesort $L $i [expr {$j-$t}]]  }  return $L } stoogesort {1 4 5 3 -6 3 7 10 -2 -5}

Output:

-6 -5 -2 1 3 3 4 5 7 10

True BASIC

SUB swap (vb1,vb2)  LET temp = vb1  LET vb1 = vb2  LET vb2 = temp END SUB SUB stoogesort (l(),i,j)  IF l(j) < l(i) THEN CALL swap (L(i), L(j))  IF (j-i) > 1 THEN  LET t = (j-i+1)/3  CALL stoogesort (l(), i, j-t)  CALL stoogesort (L(), i + t, j)  CALL stoogesort (L(), i, j - t)  END IF END SUB RANDOMIZE LET arraysize = 10 DIM x(0) MAT REDIM x(arraysize) PRINT "unsort: "; FOR i = 1 TO arraysize  LET x(i) = INT(RND*100)  PRINT x(i); " "; NEXT i PRINT CALL stoogesort (x(), 1, arraysize) PRINT " sort: "; FOR i = 1 TO arraysize  PRINT x(i); " "; NEXT i PRINT END

uBasic/4tH

Translation of: BBC BASIC

PRINT "Stooge sort:" n = FUNC (_InitArray) PROC _ShowArray (n) PROC _Stoogesort (n) PROC _ShowArray (n) PRINT END _InnerStooge PARAM(2) ' Stoogesort LOCAL(1) IF @(b@) < @(a@) Then Proc _Swap (a@, b@) IF b@ - a@ > 1 THEN c@ = (b@ - a@ + 1)/3 PROC _InnerStooge (a@, b@-c@) PROC _InnerStooge (a@+c@, b@) PROC _InnerStooge (a@, b@-c@) ENDIF RETURN _Stoogesort PARAM(1) PROC _InnerStooge (0, a@ - 1) RETURN _Swap PARAM(2) ' Swap two array elements PUSH @(a@) @(a@) = @(b@) @(b@) = POP() RETURN _InitArray ' Init example array PUSH 4, 65, 2, -31, 0, 99, 2, 83, 782, 1 FOR i = 0 TO 9 @(i) = POP() NEXT RETURN (i) _ShowArray PARAM (1) ' Show array subroutine FOR i = 0 TO a@-1 PRINT @(i), NEXT PRINT RETURN

Wren

var stoogeSort // recursive stoogeSort = Fn.new { |a, i, j|  if (a[j] < a[i]) {  var t = a[i]  a[i] = a[j]  a[j] = t  }  if (j - i > 1) {  var t = ((j - i + 1)/3).floor  stoogeSort.call(a, i, j - t)  stoogeSort.call(a, i + t, j)  stoogeSort.call(a, i, j - t)  } } var array = [ [4, 65, 2, -31, 0, 99, 2, 83, 782, 1], [7, 5, 2, 6, 1, 4, 2, 6, 3] ] for (a in array) {  System.print("Before: %(a)")  stoogeSort.call(a, 0, a.count-1)  System.print("After : %(a)")  System.print() }

Output:

Before: [4, 65, 2, -31, 0, 99, 2, 83, 782, 1] After : [-31, 0, 1, 2, 2, 4, 65, 83, 99, 782] Before: [7, 5, 2, 6, 1, 4, 2, 6, 3] After : [1, 2, 2, 3, 4, 5, 6, 6, 7]

XPL0

code ChOut=8, IntOut=11; \intrinsic routines proc StoogeSort(L, I, J); \Sort array L int L, I, J; int T; [if L(J) < L(I) then [T:= L(I); L(I):= L(J); L(J):= T]; \swap if J-I > 1 then [T:= (J-I+1)/3; StoogeSort(L, I, J-T); StoogeSort(L, I+T, J); StoogeSort(L, I, J-T); ]; ]; int A, I; [A:= [3, 1, 4, 1, -5, 9, 2, 6, 5, 4]; StoogeSort(A, 0, 10-1); for I:= 0 to 10-1 do [IntOut(0, A(I)); ChOut(0, ^ )]; ]

Output:

-5 1 1 2 3 4 4 5 6 9

Yorick

Based on pseudocode, except using Yorick's 1-based arrays. Sorts in place.

func stoogesort(&L, i, j) { if(is_void(i)) i = 1; if(is_void(j)) j = numberof(L); if(L(j) < L(i)) L([i,j]) = L([j,i]); if(j - i > 1) { t = (j - i + 1)/3; stoogesort, L, i, j-t; stoogesort, L, i+t, j; stoogesort, L, i, j-t; } }

Example interactive use:

> foo = [1,4,5,3,-6,3,7,10,-2,-5] > stoogesort, foo > foo [-6,-5,-2,1,3,3,4,5,7,10]

zkl

fcn stoogeSort(list,i=0,j=Void){ if(Void==j) j=list.len() - 1; // default parameters set before call if(list[j]<list[i]) list.swap(i,j); if(j - i >1){ t:=(j - i + 1)/3; stoogeSort(list,i , j-t); stoogeSort(list,i+t, j ); stoogeSort(list,i , j-t); } list }

stoogeSort(List(67,-201,0,9,9,231,4)).println();

Output:

L(-201,0,4,9,9,67,231)