Reverse a singly linked list.
将单链表反过来打印
是先看的答案然后会写的
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
public class Solution {
public ListNode reverseList(ListNode head) {
if(head==null) return null;
ListNode temp = head;
ListNode prev = null;
while(head!=null){
temp = head.next;//储存当前node的指针域
head.next = prev;//改变当前head node的指针域为前一个node
prev = head;//把当前的node再付给prev
head = temp;//再把当前的node往后移动一个
}
return prev;
}
}