In-Place QuickSort in Python

In-Place QuickSort.py

N = int(raw_input().strip())
ar = map(int, raw_input().strip().split())

def quicksort(ar, l, h):
    if l < h:
        pi = partition(ar, l, h)
        quicksort(ar,l,pi-1)
        quicksort(ar,pi+1, h)
def partition(ar, l, h):
    p = ar[h]
    i = l - 1
    for j in range(l,h):
        if ar[j] <= p:
            i = i + 1
            ar[i], ar[j] = ar[j], ar[i]
    ar[i+1], ar[h] = ar[h], ar[i+1]
    print " ".join(map(str, ar))
    return (i+1)
quicksort(ar, 0, N-1)
print " ".join(map(str, ar))