题解 | #反转链表#
反转链表
https://www.nowcoder.com/practice/75e878df47f24fdc9dc3e400ec6058ca
import java.util.*; /* * public class ListNode { * int val; * ListNode next = null; * public ListNode(int val) { * this.val = val; * } * } */ public 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 * @return ListNode类 */ public ListNode ReverseList (ListNode head) { // write code here ListNode newhead = null; ListNode a = head; ListNode b = head; while (a != null) { b = b.next; a.next = newhead; newhead = a; a = b; } return newhead; } }