归并排序--Python

 #-*- coding:utf-8 -*-class MergeSort:    def mergeSort(self, A, n):        if len(A)<=1:            return A        mid=len(A)/2        left=self.mergeSort(A[:mid],mid)        right=self.mergeSort(A[mid:],mid)        i=0        j=0        res=[]        while len(left)>i and len(right)>j:            if left[i]<=right[j]:                res.append(left[i])                i+=1            else:                res.append(right[j])                j+=1        res+=left[i:]        res+=right[j:]        return res`