A.sq.rear= (sq.rear+1)mod MAXSIZE; sq.elem[sq.rear]=x; B.sq.elem[sq.rear]=x; sq.rear= (sq.rear+1)mod MAXSIZE; C.sq.front= (sq.front+1)mod MAXSIZE; sq.elem[sq.front]=x; D.sq.elem[sq.front]=x; sq.front= sq.front+1;
A.sq.front= sq.rear B.sq.front= sq.rear+1 C.(sq.front +1)mod MAXSIZE= sq.rear D.(sq.rear+1)mod MAXSIZE= sq.front
A.s=q.front;q.front->next=s.next; B.s=q.front->next;q.front->next=s.next; C.s=q.front->next;q.front=s.next; D.s=q;q.front->next=s.next;