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.
判断了两个二叉树是否相等
/**
* 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],布布扣,bubuko.com
原文：http://blog.csdn.net/harryhuang1990/article/details/28092517