leetcode 每日一题 101. Symmetric Tree

class Solution {
public:
bool mySymmetric(TreeNode* left,TreeNode* right){
if(left==NULL&&right==NULL)  return true;
if(left!=NULL&&right!=NULL&&left->val==right->val)
return (mySymmetric(left->right,right->left)&&mySymmetric(left->left,right->right));
else return false;
}

bool isSymmetric(TreeNode* root) {
if(root==NULL) return true;
return mySymmetric(root->left,root->right);
}
};