Rotate List

/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode(int x) : val(x), next(NULL) {}
 * };
 */
class Solution {
public:
    ListNode *rotateRight(ListNode *head, int k) {
        if(head==NULL||head->next==NULL||k==0)
            return head;
        int length=0;
        ListNode *pCur=head;
        ListNode *pTail=head;
        while(pCur!=NULL)
        {
            length++;
            pTail=pCur;
            pCur=pCur->next;
        }
        k%=length;
        pCur=head;
        for(int i=0;i<length-k-1;i++)
            pCur=pCur->next;
        pTail->next=head;
        head=pCur->next;
        pCur->next=NULL;
        return head;
    }
};