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.

// Source : https://oj.leetcode.com/problems/same-tree/ // Author : Chao Zeng
// Date   : 2014-12-17

/**
 * 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 (!p || !q)
            return false;
        if (p->val == q->val){
            bool left = isSameTree(p->left,q->left);
            bool right = isSameTree(p->right,q->right);
            return left && right;
        }
        else
            return false;
    }
};