//树的遍历。切记,传值时候需要&
/**
* Definition for binary tree
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
int sumNumbers(TreeNode *root) {
int sum = 0;
//int presum=0;
treesum(root,0,sum);
return sum;
}
void treesum(TreeNode* root,int presum,int &sum)
{
if(root==NULL)return;
presum=root->val+presum*10;
if(root->left==NULL&&root->right==NULL)
{sum+=presum;presum=0;return;}//
treesum(root->left,presum,sum);
treesum(root->right,presum,sum);
}
};