python（三）6种排序算法性能比较（冒泡、选择、插入、希尔、快速、归并）

# coding:utf-8

import random
import time

def bubble_sort(alist):
    """冒泡"""
    n = len(alist)
    for j in range(n-1):
        count = 0
        for i in range(0, n-1-j):
            if alist[i] > alist[i+1]:
                alist[i],alist[i+1] = alist[i+1], alist[i]
                count += 1
        if 0 == count:
            return

def select_sort(alist):
    """选择"""
    n = len(alist)
    for j in range(n-1):
        min_index = j
        for i in range(j+1, n):
            if alist[min_index] > alist[i]:
                min_index = i
        alist[j], alist[min_index] = alist[min_index], alist[j]

def insert_sort(alist):
    """插入"""
    n = len(alist)
    for j in range(1, n):
        i = j
        while i > 0:
            if alist[i] < alist[i-1]:
                alist[i], alist[i-1] = alist[i-1], alist[i]
                i -= 1
            else:
                break

def shell_sort(alist):
    """希尔"""
    n = len(alist)
    gap = n // 2
    while gap > 0:
        for j in range(gap, n):
            i = j
            while i > 0:
                if alist[i] < alist[i-gap]:
                    alist[i], alist[i-gap] = alist[i-gap], alist[i]
                    i -= gap
                else:
                    break
        gap //= 2

def quick_sort(alist, first, last):
    """快速"""
    if first >= last:
        return
    mid_value = alist[first]
    low = first
    high = last
    while low < high:
        while low < high and alist[high] >= mid_value:
            high -= 1
        alist[low] = alist[high]
        while low 

作者用一万以内的1000个数字进行排序，快排胜出