LeetCode 82. 删除排序链表中的重复元素 II

public static ListNode deleteDuplicates(ListNode head) {
        if(head==null ||head.next==null)return head;
        ListNode l = new ListNode(0);
        l.next=head;
        ListNode pre = l;
        ListNode cur = head;
        while (cur!=null && cur.next!=null){
            if(cur.val == cur.next.val){
                ListNode temp = cur.next;
                while (temp!=null && temp.val==cur.val){
                    temp = temp.next;
                }
                pre.next = temp;
                cur=temp;
                continue;
            }
            pre =cur;
            cur=cur.next;
        }
        return l.next;
    }