Leetcode 100 : same Tree

Leetcode—100

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.

【题目大意】给定两棵树，判断是不是相同
【解法】同时便利两棵树，遇到树的结构或者节点值不一样，直接返回false
【AC代码】

/** * Definition for a binary tree node. * struct TreeNode { *     int val; *     struct TreeNode *left; *     struct TreeNode *right; * }; */bool isSameTree(struct TreeNode* p, struct TreeNode* q) {    if(p == NULL && q == NULL){        return true;    }    else if(p == NULL && q != NULL){        return false;    }    else if(p != NULL && q == NULL){        return false;    }    else{        if(p ->val == q ->val){            return (isSameTree(p ->left, q ->left) && isSameTree(p ->right, q ->right));        }        else{            return false;        }    }}