leetcode 83. 删除排序链表中的重复元素

 1 class Solution {
 2     public ListNode deleteDuplicates(ListNode head) {
 3         if(head==null){
 4             return head;
 5         }
 6         ListNode iterator = head.next;
 7         ListNode pre = head;
 8         ListNode next = null;
 9         int rep = head.val;
10         while(iterator!=null){
11             next=iterator.next;
12             if(iterator.val==rep){
13                 pre.next=next;
14             }else{
15                 rep=iterator.val;
16                 pre=iterator;
17             }
18             iterator=next;
19         }
20         return head;
21     }
22 }