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) {        // Start typing your C/C++ solution below        // DO NOT write int main() function        if (p == NULL && q == NULL)            return true;        else if (p == NULL || q == NULL)            return false;        return p->val == q->val && isSameTree(p->left, q->left)            && isSameTree(p->right, q->right);    }};