题目链接

力扣https://leetcode-cn.com/problems/target-sum/ 

题目描述 

题目分析 

每个元素仅取一次，01背包变形

C++实现 

class Solution {public:    int findTargetSumWays(vector& nums, int target) { int sum = 0; for(int i = 0; i  sum) return 0; if((sum + target) % 2 == 1) return 0; int BigSize = (target + sum) / 2; vector dp(BigSize + 1, 0); dp[0] = 1; for(int i = 0; i = nums[i]; j--){  dp[j] += dp[j - nums[i]];      } } return dp[BigSize];    }};