void K_Reverse( List L, int K ) 
{   //此题已经默认size >= K   因为当size < K时 反转后将不再符合链表的定义//求出表中元素个数int size = 0;for (List cur = L->Next; cur != NULL; cur = cur->Next)size++;  List prv, cur, next, first, head = L;//共需要反转 size/K 轮for (int i = 1; i <= size / K; i++) {    //每轮需要反转K-1次[每两个结点间记作一次]int j = K - 1;prv = head -> Next;     cur = prv-> Next;      first = prv;                while(j--) {next = cur -> Next;  cur -> Next = prv;  prv = cur;cur = next;  }head -> Next = prv;     first -> Next = cur;       //下一轮的哨兵位即下一轮的首结点的上一个//即上一轮的最后一个结点head = first;               }
}