/**

  * Definition for singly-linked list.

  * public class ListNode {

  *     int val;

  *     ListNode next;

  *     ListNode(int x) {

  *         val = x;

  *         next = null;

  *     }

  * }

  */

 public class Solution {

     private int getLength(ListNode head){

         int answer = 0;

         while(head != null){

             answer++;

             head = head.next;

         }

         return answer;

     }

     public ListNode rotateRight(ListNode head, int n) {

         if(head == null || head.next == null)

             return head;

         int length = getLength(head);

         if(n == 0)

             return head;

         n = n % length;

         ListNode dummy = new ListNode(0);

         dummy.next = head;

         ListNode slow = dummy;

         ListNode fast = head;

         for(int i = 0;i < n;i++)

                 fast = fast.next;

         ListNode tail = fast;

         while(fast != null){

             slow = slow.next;

             tail = fast;

             fast = fast.next;

         }

         tail.next = dummy.next;

         dummy = slow.next;

         slow.next = null;

         return dummy;

     }

 }