//利用桶的思想去重
class Solution {
    public ListNode deleteDuplication(ListNode head) {
       int arr[]=new int[100];
       ListNode point=head;

       while(point!=null)
       {
           arr[point.val]++;
           point=point.next;
       }
       point=head;
       ListNode newHead=new ListNode(100000);
       ListNode p=newHead;
       while(point!=null)
       {
           if(arr[point.val]==1)
           {
               ListNode cur=new ListNode(point.val);
               p.next=cur;
               p=p.next;
           }
           point=point.next;
       }

       newHead=newHead.next;
       return newHead;
    }
}