Leetcode 100 Same Tree 树

 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     bool isSameTree(TreeNode* p, TreeNode* q) {
13         if(!p && !q) {
14             return true;
15         }
16         else if(!p||!q){
17             return false;
18         }
19         else{
20             if(p->val != q->val) return false;
21             else return isSameTree(p->left, q->left) && 
                           isSameTree(p->right, q->right);
22         }
23     }
24 };