看见一个比较不错的评论
class Solution { public: vector<int> productExceptSelf(vector<int>& nums) { int n=nums.size(); int left=1,right=1; //left:从左边累乘,right:从右边累乘 vector<int> res(n,1); for(int i=0;i<n;++i) //最终每个元素其左右乘积进行相乘得出结果 { res[i]*=left; //乘以其左边的乘积 left*=nums[i]; res[n-1-i]*=right; //乘以其右边的乘积 right*=nums[n-1-i]; } return res; } };
我的代码,凑合
class Solution { public: vector<int> productExceptSelf(vector<int>& nums) { vector<int>temp_1(nums.size()+2); vector<int>temp_2(nums.size()+2); vector<int>result(nums.size()); int n = nums.size()-1; for(int i=0;i<temp_1.size();i++){ temp_1[i]++; temp_2[i]++; } for(int i=0;i<nums.size();i++){ temp_1[i+1] = temp_1[i]*nums[i]; temp_2[n-i+1] = temp_2[n-i+2]*nums[n-i]; } for(int i=0;i<=n;i++){ result[i] = temp_2[i+2]*temp_1[i]; } return result; } };