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.
思路：遍历看输出结果是否相同即可，代码如下：

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