单项选择题
A.FROM B.ORDER BY C.GROUP BY D.WHERE
A、内存标志 B、外存地址 C、修改标志 D、访问标志
A.sq↑.front: =sq↑.front+1; B.sq↑.front: =(sq↑.front+1)% maxsize; C.sq↑.rear: =(sq↑.rear+1)% maxsize; D.sq↑.front: =(sq↑.front+1)% (maxsize+1);