public static ListNode rotateRight2(ListNode head, int n) {//accept!!!
        if (head == null || n == 0) {
            return head;
        }
        ListNode p = head;
        int len = 1;
        while (p.next != null) {
            p = p.next;
            ++len;
        }
        n = n % len;
        n = len - n;
        System.out.println(n);
        p.next = head;
        ListNode newhead = head;
        while (n > 0) {
            newhead = newhead.next;
            p = p.next;
            --n;
        }
        p.next = null;
        return newhead;
    }