[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.

Analysis:

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