NC_16_IS_Symmetric

package org.example.interview.practice;

/**
 * @author xianzhe.ma
 * @date 2021/8/15
 */

public class NC_16_IS_Symmetric {

    public boolean isSymmetric (TreeNode root) {
        if(root == null)
            return true;
        return check(root.left,root.right);
    }

    public boolean check(TreeNode left, TreeNode right){
        if(left == null && right == null)
            return true;
        if(left == null || right == null)
            return false;
        return left.val == right.val && check(left.left,right.right) && check(left.right,right.left);
    }


      public class TreeNode {
        int val = 0;
        TreeNode left = null;
        TreeNode right = null;
      }

}