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;
        // write code here
        int i=0;
        ListNode cur = head;
        while(cur != null){
            i++;
            cur = cur.next;
        }
        int[] a = new int[i];
        for(int j=0;j<i;j++){
            a[j] = head.val;
            head = head.next;
        }
        return Judge(a);
    }
    public boolean Judge(int[] a){
        int i=0;
        int j=a.length-1;
        while(i < j){
            if(a[i] != a[j]){
                return false;
            }
            i++;
            j--;
        }
        return true;
    }
}