高质量代码-翻转链表

描述：输入一个链表，反转链表后，输出链表的所有元素。

解决：

 1 /*
 2 public class ListNode {
 3     int val;
 4     ListNode next = null;
 5 
 6     ListNode(int val) {
 7         this.val = val;
 8     }
 9 }*/
10 public class Solution {
11     public ListNode ReverseList(ListNode head) {
12         if (head == null || head.next == null) {
13             return head;
14         }
15            
16         ListNode prior = head.next;
17         head.next = null;
18         ListNode tem;
19         while (prior != null) {
20              tem = prior;
21             prior = tem.next;
22             tem.next = head;
23             head = tem;
24         }
25         return head;
26     }
27 }