leetcode --100. Same Tree

题目：https://leetcode.com/problems/same-tree/description/

代码：

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