Sorting algorithms/Stooge sort

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Sorting algorithms/Stooge sort
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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

D

<lang d>import std.stdio ;

T[] stooge(T)(ref T[] l) {

   if(l[$-1] < l[0]) {
       T t = l[0] ;
       l[0] = l[$-1] ;
       l[$-1] = t ;
   }
   if(l.length > 2) {
       T[] r ;
       int m = l.length  / 3 ;
       r = l[0..$ - m] ; stooge(r) ;
       r = l[m..$]     ; stooge(r) ;
       r = l[0..$ - m] ; stooge(r) ;
   }
   return l ;

}

void main() {

   auto num = [1, 4, 5, 3, -6, 3, 7, 10, -2, -5] ;
   writefln("%s", num.stooge) ;

}</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]

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,

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>

Tcl

Works with: Tcl version 8.5

<lang tcl>package require Tcl 8.5

proc stoogesort { L {i 0} {j ""} } {

  if {$j==""} {
     set j [expr [llength $L]-1]
  }
  set Li [lindex $L $i]
  set Lj [lindex $L $j]
  if {$Lj < $Li } {
     set L [lreplace $L $i $i $Lj]
     set L [lreplace $L $j $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