1. package com.alg.two;
    3. /**
    4.  * @author fuyao
    5.  * @date 2022年04月19日 5:20 下午
    6.  */
    7. public class IsSymmetric {
    9.     public boolean isSymmetric(Node tree){
    11.         return checkSymmetric(tree.left,tree.right);
    12.     }
    13.     public boolean checkSymmetric(Node left,Node right){
    14.         if (left == null && right == null) {
    15.             return true;
    16.         }
    17.         if (left == null || right == null){
    18.             return false;
    19.         }
    20.         if (left.value != right.value){
    21.             return false;
    22.         }
    23.         return checkSymmetric(left.left,right.right) && checkSymmetric(left.right,right.left);
    24.     }
    27.     public static void main(String[] args) {
    28.         Node node1 = new Node(1);
    29.         Node node3 = new Node(3);
    30.         Node node2 = new Node(2,node1,node3);
    31.         IsSymmetric tree = new IsSymmetric();
    32.         System.out.println(tree.isSymmetric(node2));
    33.     }
    36.     static class Node{
    37.         int value;
    38.         Node left;
    39.         Node right;
    41.         public Node(int value) {
    42.             this.value = value;
    43.         }
    45.         public Node(int value, Node left, Node right) {
    46.             this.value = value;
    47.             this.left = left;
    48.             this.right = right;
    49.         }
    50.     }
    51. }