LeetCode: Same Tree [100]

【题目】

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.

【题意】

判断了两个二叉树是否相等

【思路】

递归

【代码】

/**
 * 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==NULL && q!=NULL)return false;
        if(p!=NULL && q==NULL)return false;

        return p->val==q->val && isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
    }
};

LeetCode: Same Tree [100]