/***************************************************
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.
*******************************************************/
ListNode *rotateRight(ListNode *head, int k) {
if (head==NULL || k<=0){
return head;
}
//find the length of List
int len=1;
ListNode *p=head;
while( p->next != NULL ){
p = p->next;
len++;
}
//connect the tail to head
p->next = head;
//find the left place (take care the case - k > len)
k = len - k % len;
//find the place
for(int i=0; i<k; i++){
p = p->next;
}
//break the list
head = p->next;
p->next = NULL;
return head;
}