快速排序

快速排序是对冒泡排序的改进

def quick_sort(lists):
    quick_sort_rec(lists, 0, len(lists) - 1)

def quick_sort_rec(lists, start, end):
    if start >= end:
        return lists
    mid = lists[start]
    low = start
    high = end

    while low < high:
        while low < high and lists[high] >= mid:
            high -= 1
        if low < high:
            lists[low] = lists[high]
            low += 1
            
        while low < high and lists[low] <= mid:
            low += 1
        if low < high:
            lists[high] = lists[low]
            high -= 1
    lists[high] = mid
    quick_sort_rec(lists, start, low - 1)
    quick_sort_rec(lists, low + 1, end)

测试速度：

from random import shuffle
import time

N = 100000
# N = 100
li = list(range(N))
shuffle(li)
li1 = li.copy()

t1 = time.time()
quick_sort(li1)
# print(li1)
t2 = time.time()
print("快速排序消耗时间：", t2 - t1)

结果：

快速排序消耗时间： 0.512702465057373

可见相比于希尔排序速度又有了很大的提高