/*
public class ListNode {
int val;
ListNode next = null;
ListNode(int val) {
this.val = val;
}
}
*/
public class Solution {
public ListNode deleteDuplication(ListNode pHead)
{
if(pHead == null){
return null;
}
if(pHead.next == null){
return pHead;
}
ListNode Head = new ListNode(0);
Head.next = pHead;
ListNode pre = Head;
ListNode last = Head.next;
while(last != null){
if(last.next != null && last.val == last.next.val){
while(last.next != null && last.val == last.next.val){
last = last.next;
}
pre.next = last.next;
last = last.next;
}else{
pre = pre.next;
last = last.next;
}
}
return Head.next;
}
}