python内排序算法（冒泡 插入 选择 堆 归并 快排）

小白表示开始理解比较抽象 多看看习惯就好了～（翻白眼）

1、冒泡（n^2）

#正常def bubble_sort(lst):    l = len(lst) - 1    while l > 0:        for i in range(0, l):  # 0<=i<l            if lst[i] < lst[i+1]:                lst[i], lst[i+1] = lst[i+1], lst[i]        l -= 1    return lst

# 优化def bubble_sort(lst):    l = len(lst) - 1    while l > 0:        flag = True        for i in range(0, l):  # 0<=i<l            if lst[i] < lst[i+1]:                lst[i], lst[i+1] = lst[i+1], lst[i]                flag = False        if flag:            return lst        l -= 1    return lst

2、插入排序（n^2）

# 正常def insert_sort(lst):    l = len(lst)    for i in range(1, l):        tmp = lst[i]        for j in range(i - 1, -1, -1):            if lst[j] > tmp:                lst[j + 1] = lst[j]                lst[j] = tmp    return lst

# 二分插入def insert_sort(lst):    for i in range(1, len(lst)):        left = 0        right = i - 1        tmp = lst[i]        while left <= right:            mid = (left + right) / 2            if tmp >= lst[mid]:                left = mid + 1            if tmp < lst[mid]:                right = mid - 1        for j in range(i - 1, left - 1, -1):  # [i-1,left]            lst[j + 1] = lst[j]        lst[left] = tmp    return lst

3、选择排序（n^2）

def select_sort(lst):    l = len(lst)    for i in range(0, l):        min_tag = i        for j in range(i + 1, l):            if lst[min_tag] > lst[j]:                min_tag = j        lst[min_tag], lst[i] = lst[i], lst[min]    return lst

4、堆排序（N*logN）

def heap_sort(lst):    l = len(lst) - 1    k = l / 2    while k >= 0:        heap_one(lst, l, k)        k -= 1    for i in range(0, l + 1):        lst[0], lst[l - i] = lst[l - i], lst[0]        heap_one(lst, l - i, 0)    return lstdef heap_one(arr, l, k):    k1 = 2 * k + 1    k2 = 2 * k + 2    max_tag = k    if k1 < l and arr[k1] > arr[max_tag]:        max_tag = k1    if k2 < l and arr[k2] > arr[max_tag]:        max_tag = k2    if max_tag != k:        arr[k], arr[max_tag] = arr[max_tag], arr[k]        heap_one(arr, l, max_tag)

5、归并排序（N*logN）

def merge_sort(lst):    l = len(lst)    if l == 1:        return lst    mid = l / 2    left = merge_sort(lst[:mid])    right = merge_sort(lst[mid:])    return merge_arr(left, right)def merge_arr(left, right):    i = 0    j = 0    ret = []    while i < len(left) and j < len(right):        if left[i] <= right[j]:            ret.append(left[i])            i += 1        else:            ret.append(right[j])            j += 1    ret = ret + left[i:] + right[j:]    return ret

6、快速排序（N*logN）

def quick_sort(lst, left, right):    if left >= right:        return lst    i = left    j = right    tmp = lst[i]    while i < j:        while i < j and lst[j] > tmp:            j -= 1        lst[i] = lst[j]        while i < j and lst[i] < tmp:            i += 1        lst[j] = lst[i]    lst[i] = tmp    quick_sort(lst, left, i - 1)    quick_sort(lst, j + 1, right)    return lst