python排序算法的實現-快速排序

1、 算法描述：

1．先從數列中取出一個數作為基准數。

2．分區過程，將比這個數大的數全放到它的右邊，小於或等於它的數全放到它的左邊。

3．再對左右區間重復第二步，直到各區間只有一個數。

2、python代碼

#!/usr/bin/python
# -*- coding: utf-8 -*-

def sub_sort(array,low,high):
    key = array[low]
    while low < high:
        while low < high and array[high] >= key:
            high -= 1
        while low < high and array[high] < key:
            array[low] = array[high]
            low += 1
            array[high] = array[low]
    array[low] = key
    return low


def quick_sort(array,low,high):
     if low < high:
        key_index = sub_sort(array,low,high)
        quick_sort(array,low,key_index)
        quick_sort(array,key_index+1,high)


if __name__ == '__main__':
    array = [8,10,9,6,4,16,5,13,26,18,2,45,34,23,1,7,3]
    print array
    quick_sort(array,0,len(array)-1)
    print array

結果：

[8, 10, 9, 6, 4, 16, 5, 13, 26, 18, 2, 45, 34, 23, 1, 7, 3]
[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 13, 16, 18, 23, 26, 34, 45]