LeetCide--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)            return true;        if(q==NULL || p == NULL)            return false;        if(p->val != q->val)            return false;        bool left = isSameTree(p->left,q->left);        bool right = isSameTree(p->right,q->right);        return left&&right;    }};