题解 | #判断一个链表是否为回文结构#

import java.util.*;

/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 * }
 */

public class Solution {
    /**
     * 
     * @param head ListNode类 the head
     * @return bool布尔型
     */
     public boolean isPail(ListNode head) {
        if (head == null || head.next == null) {
            return true;
        }
        Stack<Integer> stack = new Stack<>();
        Queue<Integer> queue = new LinkedList<>();
        while (head != null){
            stack.push(head.val);
            queue.add(head.val);
            head = head.next;
        }
        while (!stack.isEmpty()){
            if (!stack.pop().equals(queue.poll()))
                return false;
        }
        return true;
    }
}