LeetCode题解——Two Sum】的更多相关文章

前言   [LeetCode 题解]系列传送门:  http://www.cnblogs.com/double-win/category/573499.html   1.题目描述 Given a set of candidate numbers (C) and a target number (T), find all unique combinations in C where the candidate numbers sums to T. The same repeated number…
前言   [LeetCode 题解]系列传送门:  http://www.cnblogs.com/double-win/category/573499.html   1.题目描述 Given an array of integers, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers suc…
题目地址:https://oj.leetcode.com/problems/two-sum/ Two Sum Given an array of integers, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers such that they add up to the target, w…
1.题目描述 2.问题分析 记录所有路径上的值,然后转换为int求和. 3.代码 vector<string> s; int sumNumbers(TreeNode* root) { traverse(root, ""); ; for(auto it = s.begin(); it != s.end(); it++) { sum += stoi(*it); } return sum; } void traverse(TreeNode *t, string str) { if…
题目大意:给出一个数组,用这些数组里的元素去凑一个target.元素可以重复取用. 感觉对这种题目还是生疏的.脑子里有想法,但是不知道怎么表达出来. 先记录下自己的递归法.应该还可以用循环实现. 回溯:罗列出所有的不重复的可能组合,每次判断:如果超出,放弃.如果不够,继续添加元素.如果刚好,存起来. 比如:a = [2 3 6 7]  target = 7 第一次,分成以下几个树去继续分叉: 2 3 6 7 第二次: 2 2 2 3 2 6 2 7 3 3 3 6 3 7 6 6 6 7  7…
1.题目描述 2.问题分析 对于每个节点,如果其左子节点是叶子,则加上它的值,如果不是,递归,再对右子节点递归即可. 3.代码 int sumOfLeftLeaves(TreeNode* root) { if (root == NULL) ; ; if (root->left != NULL) { if (root->left->left == NULL && root->left->right == NULL) ans += root->left-&g…
前言   [LeetCode 题解]系列传送门:  http://www.cnblogs.com/double-win/category/573499.html   1.题目描述 Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum. For example…
一. 题目 1. Two Sum II Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers such that they add up to the ta…
一. 题目 1. Two SumTotal Accepted: 241484 Total Submissions: 1005339 Difficulty: Easy Given an array of integers, return indices of the two numbers such that they add up to a specific target. You may assume that each input would have exactly one solutio…
我准备开始一个新系列[LeetCode题解],用来记录刷LeetCode题,顺便复习一下数据结构与算法. 1. 二叉树 二叉树(binary tree)是一种极为普遍的数据结构,树的每一个节点最多只有两个节点--左孩子结点与右孩子结点.C实现的二叉树: struct TreeNode { int val; struct TreeNode *left; // left child struct TreeNode *right; // right child }; DFS DFS的思想非常朴素:根据…