#!/usr/bin/env python

def qsort3(alist, lower, upper):

print(alist)

if lower >= upper:

return

pivot = alist[lower]

left, right = lower + 1, upper

while left <= right:

while left <= right and alist[left] < pivot:

left += 1

while left <= right and alist[right] >= pivot:

right -= 1

if left > right:

break

# swap while left <= right

alist[left], alist[right] = alist[right], alist[left]

# swap the smaller with pivot

alist[lower], alist[right] = alist[right], alist[lower]

qsort3(alist, lower, right - 1)

qsort3(alist, right + 1, upper)

unsortedArray = [8,7,6,5,4,3,2,1]

print(qsort3(unsortedArray, 0, len(unsortedArray) - 1))