【算法】删除链表中重复的结点

public class ListNode {
    int val;
    ListNode next = null;

    ListNode(int val) {
        this.val = val;
    }
    public ListNode deleteDuplication(ListNode pHead){
        if (pHead==null || 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){// 找到最后的一个相同节点       
                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;
    }
}