[LeetCode] 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.

/** * 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;        else if(p==NULL||q==NULL)        {            return false;        }        else        {            if(p->val!=q->val)            return false;            else                       //当前节点相等，判断其左右子树节点            {                if(isSameTree(p->left,q->left)&&isSameTree(p->right,q->right))                  return true;            }        }        return false;    }};