quick sort by python

quickSort.py

"""
@desc quick sort python version
@param List arr
@return List arr
"""
def quickSort(arr, left=None, right=None):

    # default parameter
    if left == None or right == None:
        left = 0
        right = len(arr) - 1

    # handler
    m = arr[left]
    i = left+1
    j = right

    # loop until i==j
    while i < j:
        # j before i
        while arr[j] >= m and i < j:
            j -= 1
        while arr[i] < m and i < j:
            i += 1
        if i != j:
            arr[i] = arr[i] + arr[j]
            arr[j] = arr[i] - arr[j]
            arr[i] = arr[i] - arr[j]
    
    # if j find number less than m
    if m > arr[j]:
        arr[left] = arr[left] + arr[j]
        arr[j] = arr[left] - arr[j]
        arr[left] = arr[left] - arr[j]
    
    # control boundary
    if left < i-1:
        quickSort(arr, left, i-1)
    if i+1 < right:
        quickSort(arr, i+1, right)

    return arr


# a = quickSort([6,1,2,7,9,3,4,5,10,8])
# print(a)
# [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]