Python实现8中常用排序算法

L = [2,6,4,7,9,1,3,5,8]

# 1.插入排序
def insert_sort(List):
	n = len(List)
	for i in range(1,n):            # 得到索引
		j = i-1                     # 获取当前元素之前的索引
		temp = List[i]
		while j >= 0:               # 当索引大于等于时开始循环
			if temp < List[j]:      # 当List[i]元素小于之前的元素
				List[j+1] = List[j] # 交换两个元素的位置
				List[j] = temp
			j -= 1                  # 继续比较交换后的list[i]和再前一个元素的大小,继续循环
	return List

print(insert_sort(L))

#2.冒泡排序
def bubble_sort(List):
	n = len(List)
	for i in range(n):
		for j in range(i+1, n):
			if List[i] > List[j]:
				List[j], List[i] = List[i], List[j]
	return List

print(bubble_sort(L))

# 3.快速排序
def quick_sort(List,low,high):
    i=low
    j=high
    if i >= j:
        return List
    key=List[i]
    while i < j:
		# 当高位游标大于基准值时, 高位游标向左移动
        while i < j and List[j]>=key:
            j = j - 1
        List[i]=List[j]
		# 当低位游标指向的值,小于基准值时, 低位游标向右移动
        while i < j and List[i]<=key:
            i = i + 1
        List[j]=List[i]
    List[i]=key
    quick_sort(List,low,i-1) # 对基准值左边的未排序队列排序
    quick_sort(List,j+1,high)# 对基准值右边的未排序队列排序
    return List

print(quick_sort(L, 0, len(L)-1))

#4.选择排序
def select_sort(List):
    length = len(List)
    for i in range(length):   # 得出全部的索引
        min_index=i           # 假设最小的索引
        for j in range(i,length):      # 获取i之后的索引
            if List[j]<List[min_index]:# 比较i 之后的元素与最小元素的大小
                min_index=j            # 如果小于最小元素,那么久交换索引
        List[i],List[min_index]=List[min_index],List[i]  # 交换最小的索引指向的值
    return List

print(select_sort(L))

#5.归并排序
def merge_sort(list):
    if len(list)<=1:
        return list
    # 根据长度确定中间位置
    mid = int(len(list)/2)
    left=merge_sort(list[:mid])
    right=merge_sort(list[mid:])
    return merge(left,right)

def merge(list1,list2):
    list=[]
    i,j=0,0
    while i<len(list1) and j<len(list2):
        if list1[i]<list2[j]:
            list.append(list1[i])
            i=i+1
        elif list1[i]>=list2[j]:
            list.append(list2[j])
            j=j+1
    list.extend(list1[i:])
    list.extend(list2[j:])
    return list

print(merge_sort(L))

#6.希尔排序
def shell_sort(List):
    step = int(len(List)/2)
    while step > 0:
        for i in range(step, int(len(List))):
            while i >= step and List[i-step] > List[i]:
                List[i], List[i-step] = List[i-step], List[i]
                i -= step
        step = int(step/2)
    return List

print(shell_sort(L))

# 7.堆排序
def adjust_heap(List, i, size):
	lchild = 2 * i + 1
	rchild = 2 * i + 2
	m = i
	if i < int(size/2) and List[lchild] > List[m]:
		m = lchild
	if rchild < size and List[rchild] > List[m]:
		m = rchild
	if m != i:
		List[m], List[i] = List[i], List[m]
		adjust_heap(List, m, size)

def build_heap(List, size):
	for i in range(0, int(size/2))[::-1]:
		adjust_heap(List, i, size)

def heap_sort(List):
	size = len(List)
	build_heap(List, size)
	for i in range(0, size)[::-1]:
		List[0], List[i] = List[i], List[0]
		adjust_heap(List, 0, i)
	return List

print(heap_sort(L))

# 8.基数排序
import math
def radix_sort(List, radix=10):
	n = int(math.ceil(math.log(max(List), radix)))
	bucket = [[] for i in range(radix)]
	for i in range(1, n + 1):
		for j in List:
			bucket[int(j/(radix**(i-1))) % (radix**i)].append(j)
		del List[:]
		for x in bucket:
			List += x
			del x[:]
	return List

print(radix_sort(L))

　　参考: https://www.cnblogs.com/wangbin2188/p/6520560.html

　　以上运行环境为: python3.7.0 win10