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 / \ \…

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…

If the depth of a tree is smaller than 5, then this tree can be represented by a list of three-digits integers. For each integer in this list: The hundreds digit represents the depth D of this node, 1 <= D <= 4. The tens digit represents the positio…

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…

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 andsum = 22, 5 / \ 4 8 / / \ 11 13 4 / \ / \ 7 2 5 1 return [ [5,4,11,2], [5,8,4,5] ] 题意:给定一数,在树中找出所有路径和等于该…

Path Sum II 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] ] 这个问题需要返…

原题链接在这里:https://leetcode.com/problems/path-sum-iv/description/ 题目: If the depth of a tree is smaller than 5, then this tree can be represented by a list of three-digits integers. For each integer in this list: The hundreds digit represents the depth …

Path Sum II 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] ] SOLUTION…

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             / \        …

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 / \ 4 8…

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 / \…

/** * Definition for binary tree * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL) {} * }; */ class Solution { public: bool hasPathSum(TreeNode *root, int sum) { ) //针对根结点,非根节点不应会执…

原题地址:https://oj.leetcode.com/problems/path-sum-ii/ 题意: 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…

Given a binary tree and a sum, find all root-to-leaf paths where each path's sum equals the given sum. 通过一个p指针,遍历 二叉树,并将每次的值 保存在 sum2 中 . 遇到右节点,将右节点+depth 保存在 temp中,当再次使用 该节点时,根据depth 将sum2中的长度削减成 depth-1 /** * Definition for a binary tree node. * st…

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] ] 给定一个二叉树和一个值.找出全部根到叶…

原题地址:https://oj.leetcode.com/problems/path-sum/ 题意: 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 =…

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…

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

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…

题意: 给一棵二叉树,每个叶子到根的路径之和为sum的,将所有可能的路径装进vector返回. 思路: 节点的值可能为负的.这样子就必须到了叶节点才能判断,而不能中途进行剪枝. /** * Definition for a binary tree node. * struct TreeNode { * int val; * TreeNode *left; * TreeNode *right; * TreeNode(int x) : val(x), left(NULL), right(NULL)…

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] ] Hide Tags Tree Depth…

问题描述: 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 nod…

1.二叉树路径求指定和,需要注意的是由于有负数,所以即使发现大于目标值也不能返回false,而且返回true的条件有两个,到叶节点且等于sum,缺一不可 public boolean hasPathSum(TreeNode root, int sum) { if (root==null) return false; if (root.val==sum&&root.left==null&&root.right==null) return true; else return h…

1.类中递归调用函数需要加self # Definition for a binary tree node # class TreeNode: # def __init__(self, x): # self.val = x # self.left = None # self.right = None class Solution: # @param root, a tree node # @param sum, an integer # @return a boolean def hasPath…

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] ] 112. Path Sum 的拓展,上一…