标签:style class blog code color 使用
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:sum
= 22
,
5 / 4 8 / / 11 13 4 / \ 7 2 1
return true, as there exist a root-to-leaf path 5->4->11->2
which sum
is 22.
思路:使用普通的深度优先搜索即可解决问题。
/** * 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) { if(root == NULL) return false; if(root->left == NULL && root->right == NULL && root->val == sum) return true; // 下述写法有点化蛇添足,会导致找到一条路径之后,再寻找其他路径 // bool left =hasPathSum(root->left, sum - root->val); // bool right = hasPathSum(root->right, sum - root->val); // return (left || right); return hasPathSum(root->left, sum - root->val) || hasPathSum(root->right, sum - root->val); } };
【Leetcode】Path Sum,布布扣,bubuko.com
标签:style class blog code color 使用
原文地址:http://blog.csdn.net/lipantechblog/article/details/32124383