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.

 * struct ListNode {

 *     int val;

 *     ListNode *next;

 *     ListNode(int x) : val(x), next(NULL) {}

 * };

 */

class Solution {

public:

    int getListLength(ListNode* head)

    {

        int len = ;

        while(head){

            len++;

            head = head->next;

        }

        return len;

    }

    ListNode* rotateRight(ListNode* head, int k) {

        int len = getListLength(head);

        k = len == ?   : len - k%len ;

        if(head ==NULL || k== || k==len){

            return head;

        }

        ListNode *newHead = NULL;

        ListNode *cur     = head;

        int cnt = ;

        while(cur){

            ++cnt;

            if(cnt == k){

                newHead = cur->next;

                cur->next=NULL;

                break;

            }

            cur = cur->next;

        }

        ListNode* p=newHead;

        while(p && p->next){

            p = p->next;

        }

        if(p){

            p->next=head;

        }

        return newHead;

    }

};