Stooge sort

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Stooge sort
Sorting stoogesort anim.gif
Visualization of Stooge sort.
Class Sorting algorithm
Data structure Array
Worst case performance O(nlog 3 /log 1.5)
Worst case space complexity O(n)

Stooge sort is a recursive sorting algorithm with a time complexity of O(nlog 3 / log 1.5 ) = O(n2.7095...). The running time of the algorithm is thus slower compared to efficient sorting algorithms, such as Merge sort, and is even slower than Bubble sort, a canonical example of a fairly inefficient and simple sort.

The algorithm is defined as follows:

  • If the value at the end is smaller than the value at the start, swap them.
  • If there are 3 or more elements in the list, then:
    • Stooge sort the initial 2/3 of the list
    • Stooge sort the final 2/3 of the list
    • Stooge sort the initial 2/3 of the list again
  • else: exit the procedure

The algorithm gets its name from slapstick routines of The Three Stooges, in which each stooge hits the other two.[citation needed]


 function stoogesort(array L, i = 0, j = length(L)-1)
     if L[j] < L[i] then
         L[i] ↔ L[j]
     if (j - i + 1) > 2 then
         t = (j - i + 1) / 3
         stoogesort(L, i  , j-t)
         stoogesort(L, i+t, j  )
         stoogesort(L, i  , j-t)
     return L


External links[edit]