题目：

题解：

struct ListNode* rotateRight(struct ListNode* head, int k) {if (k == 0 || head == NULL || head->next == NULL) {return head;}int n = 1;struct ListNode* iter = head;while (iter->next != NULL) {iter = iter->next;n++;}int add = n - k % n;if (add == n) {return head;}iter->next = head;while (add--) {iter = iter->next;}struct ListNode* ret = iter->next;iter->next = NULL;return ret;
}