剑指offer--面试题52：构建乘积数组

题目描述

给定一个数组A[0,1,...,n-1],请构建一个数组B[0,1,...,n-1],其中B中的元素B[i]=A[0]*A[1]*...*A[i-1]*A[i+1]*...*A[n-1]。不能使用除法。

python实现：

# -*- coding:utf-8 -*-
class Solution:
    def multiply(self, A):
        # write code here
        n = len(A)
        if n==0:
            return []
        b = [1]*n
        tmpProd = 1
        for i in range(1, n):
            b[i] = A[i-1]*tmpProd
            tmpProd = b[i]#tmpProd = A[i-1]*tmpProd
        print b
        tmpProd = 1
        for i in range(n-2, -1, -1):
            b[i] *= A[i+1]*tmpProd
            tmpProd = A[i+1]*tmpProd
        return b