合并二叉树

#include<iostream>

using namespace std;

struct TreeNode{
	int val;
	TreeNode* right;
	TreeNode* left;
	TreeNode(int a) :val(a), right(nullptr), left(nullptr){}
};

class MyClass
{
public:
	TreeNode* mergeTrees(TreeNode* t1, TreeNode* t2) {
		if (!t1){
			return t2;
		}
		if(!t2){
			return t1;
		}
	}
	TreeNode* res = new TreeNode(t1->val + t2->val);
	res->left = mergeTrees(t1->left, t2->left);
	res->right = mergeTrees(t1->right, t2->right);
	return res;
};