Given a list, rotate the list to the right by k places, where k is non-negative.

For example:
Given 1->2->3->4->5->NULL and k = 2,
return 4->5->1->2->3->NULL.

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/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
public class Solution {
    public ListNode rotateRight(ListNode head, int k) {
        if (head == null) return head;
        ListNode newHead = head, tail = head;
        int length = 1;
        while (tail.next != null) {
            tail = tail.next;
            length++;
        }

        if (k % length > 0) {
            for (int i = 1; i < length - k % length; i++) {
                head = head.next;
            }
            tail.next = newHead;
            newHead = head.next;
            head.next = null;
        }
        return newHead;
    }
}