[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.

/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */

 
class Solution {
public:
    bool isSameTree(TreeNode *p, TreeNode *q) {
         if(p==NULL || q==NULL){
         if(p!=NULL || q!=NULL)
            return false;
         else
            return true;
     }
     
     if((p->val == q->val)  && isSameTree(p->left,q->left) && isSameTree(p->right,q->right))
        return true;
     else
        return false;
    }
};