LintCode：旋转链表

/**
* Definition for singly-linked list.
* public class ListNode {
*     int val;
*     ListNode next;
*     ListNode(int x) {
*         val = x;
*         next = null;
*     }
* }
*/
public class Solution {
/**
* @param head: the List
* @param k: rotate to the right k places
* @return: the list after rotation
*/
public ListNode rotateRight(ListNode head, int k) {
// write your code here
if(head == null ) return null;
ListNode c = head;
int count = 0;
while(c!=null){
count++;
c = c.next;
}
ListNode x = head;
ListNode res = new ListNode(-1);
ListNode  y  =   res;
ListNode front = new ListNode(-1);
ListNode  z  =   front;
for(int i=0;i<count-k%count&&x!=null;i++){
z.next = x;
z = z.next;
x = x.next;
}
z.next = null;
while(x!=null){
y.next = x;
y = y.next;
x = x.next;
}
y.next = front.next;
return res.next;
}
}