这道题是LeetCode里的第112道题.是我在学数据结构——二叉树的时候碰见的题.题目要求: 给定一个二叉树和一个目标和,判断该树中是否存在根节点到叶子节点的路径,这条路径上所有节点值相加等于目标和. 说明: 叶子节点是指没有子节点的节点. 示例: 给定如下二叉树,以及目标和 sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 返回 true, 因为存在目标和为 22 的根节点到叶子节点的路径 5->4->11->2. 本来是一道简单的题目,却因…

题目: 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. Note: A leaf is a node with no children. Example: Given the below binary tree and sum = 22, 5 / \…

给定一棵二叉树和一个总和,确定该树中是否存在根到叶的路径,这条路径的所有值相加等于给定的总和.例如:给定下面的二叉树和 总和 = 22,              5             / \            4   8           /   / \          11  13  4         /  \      \        7    2      1返回 true, 因为存在总和为 22 的根到叶的路径 5->4->11->2.详见:https://l…

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:Given the below binary tree andsum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 return true,…

要求给定树,与路径和,判断是否存在从跟到叶子之和为给定值的路径.比如下图中,给定路径之和为22,存在路径<5,4,11,2>,因此返回true;否则返回false. 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 5思路递归,从跟到叶子判断,如果在叶子处剩下的给定值恰好为给定值,那么返回ture.参考代码 /** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * T…

LeetCode:Path Sum 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:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \…

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 DFS 回溯 BFS 栈 日期 题目地址:https://leetcode.com/problems/path-sum/#/description 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…

You are given a binary tree in which each node contains an integer value. Find the number of paths that sum to a given value. The path does not need to start or end at the root or a leaf, but it must go downwards (traveling only from parent nodes to…

Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. For example:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ / \ 7 2 5 1 return [ [5,4,11,2], [5,8,4,5] ] 这道二叉树路径之和在之前的基础上又需要找…

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:Given the below binary tree and sum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ \ 7 2 1 return true…