Remove duplicates from Sorted List Java

Given a sorted linked list, delete all duplicates such this each element appear only once.

For example,
Given 1->1->2 , return 1->2 .
Given 1->1->2->3->3 , return 1->2->3 .

Idea: Define two pointers, pre and cur, if cur and pre are equal, then cur move, if not equal, move at the same time.

public class Solution {public    ListNode deleteduplicates (ListNode head) {         if (head==null| | Head.next==null)//First empty return head; ListNode pre=head;//before the pointer listnode cur=head.next;//after the pointer while (CUR!=NULL)//After the pointer is not empty {if (cur.val==pre.val)//equal, moved after the pointer, Let pre.next=cur {pre.next=cur.next; cur=cur.next;} else//not equal while moving {pre=cur; cur=cur.next;}} Return head;//final direct return to head    }}

　　

Remove duplicates from Sorted List Java