Leetcode101.对称二叉树

题目

 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 };

 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        queue<TreeNode*>queue1;
 9        queue1.push(p);queue1.push(q);
10        while(!queue1.empty()) {
11         p = queue1.front();queue1.pop();
12         q = queue1.front();queue1.pop();
13 
14         if(!p && !q) continue;
15         if((!p || !q) || p->val != q->val)  return false;
16          
17         queue1.push(p->left);     
18         queue1.push(q->right);
19         queue1.push(p->right);
20         queue1.push(q->left);
21 
22        }
23        return true;
24     }
25 };