https://leetcode.com/problems/path-sum/
使用递归的方法
/** * Definition for a binary tree node. * 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; } bool left_res=false; bool right_res=false; if(root->left==NULL&&root->right==NULL) { if(sum==root->val) return true; } if(root->left!=NULL) { left_res=hasPathSum(root->left,sum-(root->val)); } if(left_res==false&&root->right!=NULL) { right_res=hasPathSum(root->right,sum-(root->val)); } if(left_res==true||right_res==true) return true; else return false; } };