删除链表中重复的结点

public ListNode deleteDuplication(ListNode pHead)
{
    if(pHead == null || pHead.next == null)
    {
        return pHead;
    }
    ListNode  next = pHead.next;
    if(pHead.val == next.val)
    {
        while(next != null && pHead.val == next.val)
        {
             next = next.next;
        }
        return deleteDuplication(next);
    }else
    {
        pHead.next = deleteDuplication(pHead.next);
        return pHead;
    }
}