return self.hasPathSum(root.left, sum - root.val) or self.hasPathSum(root.right, sum - root.val) 1. 2. 3. 4. 这种代码的错误在,没有判断 root 是否为叶子节点。比如 root 为空的话,题目的意思是要返回 False 的,而上面的代码会返回 sum == 0。又比如,对于测试用例 树为[1,2]...
* }*/publicclassSolution {publicList<List<Integer>> pathSum(TreeNode root,intsum) { List<List<Integer>> res =newArrayList<>();if(root==null)returnres; List<Integer> list =newArrayList<>(); getPath(res,list,root,sum);returnres; }publicvoidgetPath( List<List<Integer>> res,List<Integer...
java版本代码如下,方法相同,就是java的引用处理起来稍微麻烦点,递归尾部应该pop一下。 1publicclassSolution {2publicList<List<Integer>> pathSum(TreeNode root,intsum) {3List<List<Integer>> ret =newArrayList<List<Integer>>();4Stack<Integer> tmp =newStack<Integer>();5dfs(ret, tmp, root, sum);6...
public boolean hasPathSum(TreeNode root, int sum) { if(root==null) return false; if(root.val == sum && root.left==null && root.right==null) return true; return hasPathSum(root.left, sum-root.val) || hasPathSum(root.right, sum-root.val); } } 2018/2 class Solution: def hasP...
LeetCode -- Path Sum III分析及实现方法 题目描述: 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...
112. Path Sum,就是问题1,是否有解,递归遍历所有叶结点即可。 Loading...leetcode.com/problems/path-sum/ classSolution{publicbooleanhasPathSum(TreeNoderoot,intsum){if(root==null)returnfalse;if(root.left==null&&root.right==null){if(sum==root.val)returntrue;elsereturnfalse;}else{returnhasPat...
LeetCode-112. 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. Note:A leaf is a node with no children. Example: Given the below binary tree and sum = 22...
Can you solve this real interview question? Path Sum II - Given the root of a binary tree and an integer targetSum, return all root-to-leaf paths where the sum of the node values in the path equals targetSum. Each path should be returned as a list of the
[Leetcode][python]Path Sum II/路径总和 II 题目大意 将根到叶子的路径和为sum的路径都枚举出来。 解题思路 递归,并且用了python函数嵌套,有关函数嵌套可以看这一篇文章 其实一开始不想项标准答案一样用函数嵌套,毕竟别的语言可能不支持,以后看答案不方便,但是如果把list_all放在全局,需要每轮都去清空它,而...
#Definitionfora binary tree node.#classTreeNode(object):#def__init__(self,x):#self.val=x#self.left=None#self.right=NoneclassSolution(object):defhasPathSum(self,root,sum):""":type root:TreeNode:type sum:int:rtype:bool"""ifnot root:returnFalse ...