剑指offer—删除链表中重复的结点

public class Solution {
public ListNode deleteDuplication(ListNode pHead)
{
if(pHead==null || pHead.next==null) return pHead;
ListNode pre = new ListNode(0);
pre.next = pHead;
ListNode realHead = pre;
ListNode cur = pHead;
while(cur!=null && cur.next!=null){
if(cur.next!=null && cur.val==cur.next.val){
while(cur.next!= null && cur.val==cur.next.val){
cur = cur.next;
}
cur = cur.next;
pre.next = cur;
}else{
pre = cur;
cur = cur.next;
}
}
return realHead.next;
}
}