using System;
using System.Collections.Generic;

/*
public class ListNode
{
	public int val;
	public ListNode next;

	public ListNode (int x)
	{
		val = x;
	}
}
*/

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 the head
     * @return bool布尔型
     */
    public bool isPail (ListNode head) {
        // write code here
        if(head == null || head.next == null)
            return true;
        var list = new List<int>();
        while(head != null)
        {
            list.Add(head.val);
            head = head.next;
        }
        for(var i = 0; i < list.Count / 2; ++i)
        {
            if(list[i] != list[list.Count - 1 - i])
            {
                return false;
            }
        }
        return true;
    }
}