题解 | #判断一个链表是否为回文结构#

using System;
using System.Collections.Generic;
using System.Text;

/*
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)
            return false;
        List<int> listN = new List<int>();
        List<int> listNR = new List<int>();
        while (head != null) {
            listN.Add(head.val);
            listNR.Insert(0, head.val);
            head = head.next;
        }
        int i = 0;
        for (; i < listN.Count && listN[i] == listNR[i]; i++) { }
        return i == listN.Count;
    }
}