A.生产者:wait(s);
wait(e);
append();
signal(n);
signal(s);消费者:
wait(s);
wait(n);
take();
signal(e);
signal(s);
B.
生产者:wait(s);
wait(e);
append();
signal(n);
signal(s);消费者:
wait(n);
wait(s);
take();
signal(s);
signal(e);
C.
生产者:wait(e);
wait(s);
append();
signal(s);
signal(n);消费者:
wait(s);
wait(n);
take();
signal(e);
signal(s);
D.
生产者:wait(e);
wait(s);
append();
signal(s);
signal(n);消费者:
wait(n);
wait(s);
take();
signal(s);
signal(e);