python 快速排序 qsort

 

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

def qsort(arr, start, end):     if start > end: return     def partition(arr, start, end):         pivot = arr[start]         i = start+1         while i <= end:             if pivot < arr[i]:                 arr[i], arr[end] = arr[end], arr[i]                 end -= 1             else:                 i += 1         if end > start:             arr[start], arr[end] = arr[end], arr[start]         return end     mid = partition(arr, start, end)     qsort(arr, start, mid-1)     qsort(arr, mid+1, end)   arr = [] qsort(arr,0, -1) print arr   from random import randint for k in range(1, 100):     arr = [randint(0,100) for i in range(k)]     arr2 = (list(arr))     qsort(arr, 0, len(arr)-1)     arr2.sort()     for j in range(0, len(arr)):         assert arr[j] == arr2[j]