Python_排序_插入排序

输入一个数组，返回一个排好序的数组。需要使用插入排序算法

样例输入：

[8, 5, 2, 9, 5, 6, 3]

整个过程类似于在头部开始建立一个不断增加的子数组，如果组数组后边的元素比子数组末尾的元素小，就把这个元素向前进行交换，直到这个元素比子数组中所有的元素都要小为止。

样例输出：

[2, 3, 5, 5, 6, 8, 9]

Solution:

test_array = [8, 5, 2, 9, 5, 6, 3]

def insertionSort(array):
    # Write your code here.
    for i in range(1,len(array)):
    	#second index j
    	j = i
    	while j>0 and array[j]<array[j-1]:
    		array = swap(j,j-1,array)
    		j -= 1
    return array
    
def swap(a,b,array_toswap):
	array_toswap[a],array_toswap[b] = array_toswap[b],array_toswap[a]
	return array_toswap

# print(sorted(test_array))
print(insertionSort(array = test_array))

#Space: O(1)
#Time: O(n^2)

中间过程：

[5, 8, 2, 9, 5, 6, 3]
[5, 2, 8, 9, 5, 6, 3]
[2, 5, 8, 9, 5, 6, 3]
[2, 5, 8, 5, 9, 6, 3]
[2, 5, 5, 8, 9, 6, 3]
[2, 5, 5, 8, 6, 9, 3]
[2, 5, 5, 6, 8, 9, 3]
[2, 5, 5, 6, 8, 3, 9]
[2, 5, 5, 6, 3, 8, 9]
[2, 5, 5, 3, 6, 8, 9]
[2, 5, 3, 5, 6, 8, 9]
[2, 3, 5, 5, 6, 8, 9]
[2, 3, 5, 5, 6, 8, 9]

Space: O(1)

#Time: O(n^2)