Leetcode101.对称二叉树

 1 class Solution {
 2 public:
 3     
 4     bool isSymmetric(TreeNode* root) {
 5        return  check(root,root);
 6     }
 7     bool check(TreeNode* p,TreeNode* q) {
 8        if(!p && !q ) return true;
 9        if(!p || !q ) return false;
10        return   (p->val == q->val) && check(p->left,q->right) && check(p->right,q->left);
11     }
12 };