题解 | #判断一个链表是否为回文结构#

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;
        Stack<int> stack = new Stack<int>();
        List<int> list = new List<int>();
        ListNode t = head;
        while (t != null) {
            stack.Push(t.val);
            list.Add(t.val);
            t = t.next;
        }
        //存放反过来的链表数
        List<int> re = new List<int>();
        while (stack.Count != 0) {
            re.Add(stack.Pop());
        }
        for (int i = 0; i < re.Count; i++) {
            if (re[i] != list[i]) {
                return false;
            }
        }
        return true;
    }
}