/**
 * 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:
 int mysum(TreeNode* root, int sum)
 {
  if (!root) return 0;
  else if (!root->left && !root->right)  return sum * 10 + root->val;
  return mysum(root->left, sum * 10 + root->val) + mysum(root->right, sum * 10 + root->val);
 }
 int sumNumbers(TreeNode* root) {
  int sum = 0;
  return mysum(root, sum);
 }
};