Python3实现快速排序

def quick_sort(arr, start=0, end=len(arr)-1):
    if start >= end:
        return
    paviot = partition2(arr, start, end)
    # paviot = partition2(arr, start, end)
    quick_sort(arr, start, paviot-1)
    quick_sort(arr, paviot+1, end)


# 挖坑法
def partition(arr, start, end):
    paviot = arr[start]
    left = start
    right = end
    index = start
    while right > left:
        while right > left:
            if arr[right] < paviot:
                arr[left] = arr[right]
                left += 1
                index = right
                break
            right -= 1
        while right > left:
            if arr[left] > paviot:
                arr[right] = arr[left]
                right -= 1
                index = left
                break
            left += 1
    arr[index] = paviot
    return index

# 指针交换法, 比挖坑法交换次数更少
def partition2(arr, start, end):
    paviot = arr[start]
    left = start
    right = end
    while left < right:
        while right > left and arr[right] > paviot:
            right -= 1
        while right > left and arr[left] <= paviot:
            left += 1
        if right > left:
            arr[left], arr[right] = arr[right], arr[left]
    arr[start], arr[left] = arr[left], paviot
    return left

if __name__ == '__main__':
    arr = [5,3,1,7,6,1,0,9,2,8,4,4]
    quick_sort(arr)
    print(arr)