/**
* struct TreeNode {
* int val;
* struct TreeNode *left;
* struct TreeNode *right;
* };
*/
class Solution {
public:
/**
*
* @param t1 TreeNode类
* @param t2 TreeNode类
* @return TreeNode类
*/
TreeNode* mergeTrees(TreeNode* t1, TreeNode* t2) {
// write code here
if(!t1) return t2;
if(!t2) return t1;
t1->val += t2->val;
t1->left = mergeTrees(t1->left, t2->left);
t1->right = mergeTrees(t1->right, t2->right);
return t1;
}
};