LeetCode:Same Tree

Given two binary trees, write a function to check if they are equal or not.

Two binary trees are considered equal if they are structurally identical and the nodes have the same value.

 1 /**
 2  * Definition for binary tree
 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==NULL&&q==NULL)
14         {
15             return true;
16         }
17         if(p&&q&&p->val==q->val)
18         {
19             return (isSameTree(p->left,q->left))&&(isSameTree(p->right,q->right));
20         }
21         else
22         {
23             return false;
24         }
25     }
26 };