题目描述

点这里

思路分析

二叉树上dfs暴搜

代码实现

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    int res;
    int sumNumbers(TreeNode* root) {
        dfs(root,0);
        return res;
    }
    
    void dfs(TreeNode* u,int cur){
        cur=cur*10+u->val;
        if(!u->left&&!u->right){
            res+=cur;
            return;
        }
        if(u->left) dfs(u->left,cur);
        if(u->right)dfs(u->right,cur);
    }
};