题解 | #牛群编号的回文顺序#

import java.util.*;

/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 *   public ListNode(int val) {
 *     this.val = val;
 *   }
 * }
 */

public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param head ListNode类 
     * @return bool布尔型
     */
    public boolean isPalindrome (ListNode head) {
        // write code here

         if(head.next==null){
            return true;
         }

        ListNode cur = head;
        Stack<Integer> stack = new Stack<Integer>();
        while(cur!=null){
            stack.push(cur.val);
            cur = cur.next;
        }

        ListNode check = head;
        while(check!=null){
            if(stack.pop()==check.val){
                check = check.next;
            }else{
                return false;
            }
        }

        return true;




    }
}