Python实现二路归并排序

# -*- coding:utf-8 -*-
 


def merge(left,right):
    
    i , j = 0,0
    lists = []
    while i < len(left) and j < len(right):
        if left[i] <= right[j]:
            lists.append(left[i])
            i += 1
        else:
            lists.append(right[j])
            j += 1
    lists += left[i:]
    lists += right[j:]
    return lists
    print(lists)
                
    
def mergeSort(A):
    if len(A) <= 1:
        return A
    num = int(len(A)/2)   
    print(num) 
    left = mergeSort(A[:num])
    right = mergeSort(A[num:])
    return  merge(left,right)
          
if __name__=='__main__':
    A = [10,9,8,7,6,5,4,3,2,1]
    A= mergeSort(A)
    print(A)