1 /**
2 * Definition for a binary tree node.
3 * struct TreeNode {
4 * int val;
5 * TreeNode *left;
6 * TreeNode *right;
7 * TreeNode(int x) : val(x), left(NULL), right(NULL) {}
8 * };
9 */
10 class Solution {
11 public:
12 int sum;
13
14 void process(TreeNode* root, int& sum, int cur){
15
16 cur = cur * 10 + root->val;
17 if(!root->left && !root->right){
18 sum += cur;
19 return;
20 }
21 if(root->left) process(root->left, sum, cur);
22 if(root->right) process(root->right, sum, cur);
23
24 }
25
26 int sumNumbers(TreeNode* root) {
27 if(!root) return 0;
28
29 sum = 0;
30 process(root, sum, 0);
31 return sum;
32 }
33 };
