1 package com.cskaoyan.linkedlist;
2 //反转数组
3 public class LinkedListDemo2 {
4 public static Node reverse(Node head){
5 //若输入head是null 或者这个链表只有一个元素,不需要反转
6 //null -->null
7 //a,null-->a,null
8 if(head==null||head.next==null) return head ;
9 Node prev=null;
10 Node curr=head;
11 while(curr!=null){
12 Node nextNode=curr.next;
13 curr.next=prev;
14 prev=curr;
15 curr=nextNode;
16 }
17 return prev;
18 }
19 //使用递归使链表逆序
20 public static Node reverse1(Node head){
21 if (head == null || head.next == null) return head;
22 Node node=reverse1(head.next);
23 head.next.next=head;
24 head.next = null;
25 return node;
26 }
27 public static void main(String[] args) {
28 Node node = new Node(3);
29 node = new Node(2, node);
30 node = new Node(1, node);
31 Node head = reverse(node);
32 System.out.print(head.val + " ");
33 }
34 }
1 package com.cskaoyan.linkedlist;
2
3 public class Node {
4 int val;
5 Node next;
6 public Node(int val){
7 this.val=val;
8 }
9 public Node(int val,Node next){
10 this.val=val;
11 this.next=next;
12 }
13 }
