lc 494 Target Sum 494 Target Sum You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol. Find out how many ways to assign…

You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol. Find out how many ways to assign symbols to make sum of integers…

这是一道水题,作为没有货的水货楼主如是说. 题意:已知一个数组nums {a1,a2,a3,.....,an}(其中0<ai <=1000(1<=k<=n, n<=20))和一个数S c1a1c2a2c3a3......cnan = S, 其中ci(1<=i<=n)可以在加号和减号之中任选. 求有多少种{c1,c2,c3,...,cn}的排列能使上述等式成立. 例如: 输入:nums is [1, 1, 1, 1, 1], S is 3. 输出 : 5符合要求5种…

You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol. Find out how many ways to assign symbols to make sum of integers…

问题描述 You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol. Find out how many ways to assign symbols to make sum of inte…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 动态规划 日期 题目地址:https://leetcode.com/problems/target-sum/description/ 题目描述 You are given a list of non-negative integers, a1, a2, -, an, and a target, S. Now you have 2 symbols +…

题目如下: 解题思路:这题可以用动态规划来做.记dp[i][j] = x,表示使用nums的第0个到第i个之间的所有元素得到数值j有x种方法,那么很容易得到递推关系式,dp[i][j] = dp[i-1][j - nums[i]] + dp[i-1][j + nums[i]].考虑到j可以为负数,因为j的取值范围是[-sum(nums) ,sum(nums)],为了保证在dp数组中的j一直为正数,我们做一个数组的向右平移,平移sum(nums)的长度,即把-sum(nums) 移动到0. 代码如…

https://leetcode.com/problems/target-sum/#/description You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol. Find out h…

You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol. Find out how many ways to assign symbols to make sum of integers…

［抄题］: You are given a list of non-negative integers, a1, a2, ..., an, and a target, S. Now you have 2 symbols + and -. For each integer, you should choose one from + and - as its new symbol. Find out how many ways to assign symbols to make sum of int…