leetcode100 Same Tree

100. Same Tree

Total Accepted: 114518 Total Submissions: 267060 Difficulty: Easy

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 a binary tree node.
 * 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 (NULL == p && NULL == q)
            return true;
        if ((!p && q) || (p && !q) || (p->val != q->val))
            return false;
        return (isSameTree(p->left, q->left) && isSameTree(q->right, p->right));
    }
};