Sorting algorithms/Stooge sort
You are encouraged to solve this task according to the task description, using any language you may know.
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:
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
This page uses content from Wikipedia. The original article was at Stooge sort. 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) |
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
Ada
Using slices and 'First / 'Last removes the need for I / J parameters.
<lang Ada>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;</lang>
Output:
-6, -5, -3, -2, 1, 3, 3, 4, 5, 5, 7, 7, 7, 9, 10
BASIC
This might work with older versions of QB, but that is untested. It definitely does not work with QBasic.
<lang 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</lang>
Sample outputs:
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
C
<lang 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;
}</lang>
C#
<lang C sharp|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); } }</lang>
D
<lang d>import std.stdio, std.algorithm;
void stoogeSort(T)(T[] seq) {
if (seq[$-1] < seq[0]) swap(seq[0], seq[$-1]);
if (seq.length > 2) { int m = seq.length / 3; stoogeSort(seq[0 .. $ - m]); stoogeSort(seq[m .. $]); stoogeSort(seq[0 .. $ - m]); }
}
void main() {
auto data = [1, 4, 5, 3, -6, 3, 7, 10, -2, -5]; stoogeSort(data); writeln(data);
}</lang>
Euphoria
<lang 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)</lang>
Output:
{875,616,725,922,463,740,949,476,697,455} {455,463,476,616,697,725,740,875,922,949}
Fortran
<lang fortran>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</lang>
Go
<lang 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]) }
}</lang>
Haskell
<lang 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</lang> Example: <lang haskell>*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]</lang>
Icon and Unicon
<lang Icon>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</lang>
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.
Abbreviated sample output:
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)
J
<lang 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.
)</lang> Example: <lang j> (,: 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 </lang>
Java
<lang 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); } }
}</lang> Output:
[-6, -5, -2, 1, 3, 3, 4, 5, 7, 10]
Lua
An example using a Y combinator for anonymous recursion and made generic with an optional predicate parameter.
<lang lua> 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}))
</lang>
MATLAB
<lang MATLAB>%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</lang> Sample Output: <lang MATLAB>>> stoogeSort([1 -6 4 -9],1,4)
ans =
-9 -6 1 4</lang>
NetRexx
<lang 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_
</lang>
- 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]
Objeck
<lang 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); }; } }
} </lang>
OCaml
<lang 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)</lang>
testing: <lang ocaml>let () =
let ar = [| 3; 1; 7; 2; 6; 5; 4; 9; 8 |] in stoogesort ar; Array.iter (Printf.printf " %d") ar; print_newline()</lang>
Oz
<lang 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</lang>
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
<lang parigp>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) )
};</lang>
Perl
<lang 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";
</lang>
Perl 6
<lang perl6>sub stoogesort( @L is rw, $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; </lang>
PHP
<lang 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 - $t); } } </lang>
PicoLisp
<lang PicoLisp>(de stoogeSort (L N)
(default N (length L)) (let P (nth L N) (when (> (car L) (car P)) (xchg L P) ) ) (when (> N 2) (let D (/ N 3) (stoogeSort L (- N D)) (stoogeSort (nth L (inc D)) (- N D)) (stoogeSort L (- N D)) ) ) L )</lang>
Test:
: (apply < (stoogeSort (make (do 100 (link (rand)))))) -> T
PL/I
<lang PL/I>stoogesort: procedure (L) recursive; /* 16 August 2010 */
declare L(*) fixed binary; declare (i, j, t, temp) fixed binary;
j = hbound(L,1); do i = lbound(L, 1) to j; if L(j) < L(i) then do; temp = L(i); L(i) = L(j); L(j) = temp; end; if j - i > 1 then do; t = (j - i + 1)/3; call stoogesort(L, i , j-t); call stoogesort(L, i+t, j ); call stoogesort(L, i , j-t); end; end;
end stoogesort;</lang>
PowerBASIC
PowerBASIC for DOS can use the BASIC code above, by removing CONST
and changing all instances of arraysize
to %arraysize
(note the percent sign).
This version is closely based on the BASIC code above.
<lang powerbasic>%arraysize = 10
SUB stoogesort (L() AS LONG, i AS LONG, j AS LONG)
IF L(j) < L(i) THEN SWAP L(i), L(j) IF (j - i) > 1 THEN DIM t AS LONG t = (j - i + 1) / 3 stoogesort L(), i, j - t stoogesort L(), i + t, j stoogesort L(), i, j - t END IF
END SUB
FUNCTION PBMAIN () AS LONG
RANDOMIZE TIMER
DIM x(%arraysize) AS LONG DIM i AS LONG, s AS STRING
s = "Before: " FOR i = 0 TO %arraysize x(i) = INT(RND * 100) s = s & STR$(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</lang>
Sample outputs:
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
<lang 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</lang>
PureBasic
<lang 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</lang> Implementation may be as<lang PureBasic>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</lang>
Python
<lang 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]</lang>
This alternate solution uses a wrapper function to compute the initial value of j rather than detecting the sentinel value None. <lang python>>>> 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]</lang>
REXX
<lang REXX> /*REXX program to sort an integer array L, elements start at zero.*/
highItem=19 /*define a score of elements*/ widthH=length(highItem) /*width of biggest element#.*/ widthL=0 /*width of largest element. */
do k=0 to highItem /*populate the array. */ L.k=2*k + (k * -1**k) /*kinda generate randomish#.*/ if L.k==0 then L.k=-100-k /*if zero, make a negative# */ widthL=max(widthL,length(L.k)) /*compute max width so far. */ end
call showL 'before sort' /*show before array elements*/ call stoogeSort 0,highItem /*invoke the Stooge Sort. */ call showL ' after sort' /*show after array elements*/ exit
showL: sepLength=22+widthH+widthL /*compute seperator width. */ say copies('-',sepLength) /*show 1st seperator line. */
do j=0 to highItem say 'element' right(j,widthH) arg(1)":" right(L.j,widthL) end
say copies('=',sepLength) /*show 2nd seperator line. */ return
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/ stoogeSort: procedure expose L.; parse arg i,j /*sort from I to J*/
if L.j<L.i then do /*swap L.i and L.j */
swap=L.i L.i=L.j L.j=swap end
if j-i>1 then do
t=(j-i+1)%3 /* % is integer division.*/ call stoogesort i , j-t call stoogesort i+t, j call stoogesort i , j-t end
return /*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/ </lang> Output:
---------------------------- 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: 7 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: 42 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: -100 element 1 after sort: 1 element 2 after sort: 3 element 3 after sort: 5 element 4 after sort: 6 element 5 after sort: 7 element 6 after sort: 9 element 7 after sort: 11 element 8 after sort: 12 element 9 after sort: 13 element 10 after sort: 15 element 11 after sort: 17 element 12 after sort: 18 element 13 after sort: 19 element 14 after sort: 24 element 15 after sort: 30 element 16 after sort: 36 element 17 after sort: 42 element 18 after sort: 48 element 19 after sort: 54 ============================
Ruby
<lang 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 </lang>
output
[-6, -5, -2, 1, 3, 3, 4, 5, 7, 10]
Smalltalk
<lang 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.</lang>
Tcl
<lang tcl>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}</lang> Output:
-6 -5 -2 1 3 3 4 5 7 10
Yorick
Based on pseudocode, except using Yorick's 1-based arrays. Sorts in place. <lang yorick>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; }
}</lang>
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]