A.遞歸部分B.終止條件和遞歸部分C.迭代部分D.終止條件和迭代部分
A.rear->next=s;s->next=head B.s->next=rear;rear->next=head C.rear=s;s->next=head D.rear->next=s;s=head
A.空B.滿C.上溢D.下溢