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

Example 1:

Input: 1->2->3->4->5->NULL, k = 2
Output: 4->5->1->2->3->NULL
Explanation:
rotate 1 steps to the right: 5->1->2->3->4->NULL
rotate 2 steps to the right: 4->5->1->2->3->NULL

Example 2:

Input: 0->1->2->NULL, k = 4
Output: 2->0->1->NULL
Explanation:
rotate 1 steps to the right: 2->0->1->NULL
rotate 2 steps to the right: 1->2->0->NULL
rotate 3 steps to the right: 0->1->2->NULL
rotate 4 steps to the right: 2->0->1->NULL

真的没啥好讲的

数明白数就好了

class Solution {
public:
    ListNode* rotateRight(ListNode* head, int k) {
        int n=0;
        ListNode* p=head;
        while(p!=NULL){
            n++;
            p=p->next;
        }
        if(n==0)
            return head;
        k=k%n;
        k=n-k;
        if(k==n)
            return head;
        ListNode *k1=head,*k2=head,*k3=head;
        for(int i=0;i<n-1;i++){
            if(i<k-1)
                k1=k1->next;
            if(i<k)
                k3=k3->next;
            k2=k2->next;
        }
        k2->next=head;
        k1->next=NULL;
        return k3;
    }
};