本文实例为大家分享了python实现排序算法的具体代码，供大家参考，具体内容如下
一、冒泡排序
|
1
2
3
4
5
6
7
8
9
10
11
|
def bububle_sort(alist): """冒泡排序(稳定|n^2m)""" 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]: count +=1 alist[i], alist[i+1] = alist[i+1], alist[i] if count==0: return |
二、选择排序
|
1
2
3
4
5
6
7
8
9
|
def select_sort(alist): """选择排序(不稳定|n^2)""" 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] |
三、插入排序
|
1
2
3
4
5
6
7
8
9
10
11
|
def insert_sort(alist): """插入排序(稳定|n^2)""" 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 |
四、希尔排序
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
|
def shell_sort(alist): """希尔排序(不稳定|n^2)""" n = len(alist) gap = n//2 while gap>=1: 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 |
五、快速排序
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
|
def quick_sort(alist, first, last): """快速排序(不稳定|n^2)""" if first >= last: return mid_value = alist[first] low = first high = last while low < high: #high左移 while low <high and alist[high] >= mid_value: high -= 1 alist[low] = alist[high] #low右移 while low < high and alist[low] < mid_value: low += 1 alist[high] =alist[low] #从循环退出时，low=high alist[low] = mid_value #对low左边的列表执行快速排序 quick_sort(alist, first, low-1) #对low右边的列表执行快速排序 quick_sort(alist, low+1, last) |
六、归并排序
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
def merge_sort(alist): """归并排序(稳定|nlgn)""" n = len(alist) if n <= 1: return alist mid = n//2 #left 采用归并排序后形成新的有序列表 left_li = merge_sort(alist[:mid]) #right 采用归并排序后形成新的有序列表 right_li = merge_sort(alist[mid:]) #merge(left, right) 将两个有序的子序列合并为一个新的整体 left_pointer, right_pointer = 0, 0 result = [] while left_pointer < len(left_li) and right_pointer<len(right_li): if left_li[left_pointer] < right_li[right_pointer]: result.append(left_li[left_pointer]) left_pointer += 1 else: result.append(right_li[right_pointer]) right_pointer += 1 result += left_li[left_pointer:] result += right_li[right_pointer:] return result |
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持服务器之家。
原文链接：https://blog.csdn.net/weixin_38748717/article/details/79427316
