Rotate List

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.

 

/**
 * 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 || k == 0) {
        	return head;
        }
        ListNode p = head;
        int len = 1;
        while (p.next != null) {
        	len++;
        	p = p.next;
        }
        p.next = head;
        k = k % len;
        for (int i = 0; i < len - k; i++) {
			p = p.next;
		}
        head = p.next;
        p.next = null;
        return head;
    }
}