WEI-CHENG CHEN

說明

跟 100 一樣，只是它改成鏡像左右要顛倒

解題

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