给大家出个多进程的题 - 未名空间MITBBS历史存档

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给大家出个多进程的题

给大家出个多进程的题# Programming - 葵花宝典

l*c2008-02-11 08:02

1 楼

今天下午没事编出来个题，呵呵。
Implement a multi-consumer multi-producer model such that:
1. each consumer could consume multiple resources at a time, which means each
consumer must get a given number of resource at once. The interface of the
consumer would look like: void consumer(int n) where n is the number of resource it
needs at once.
2. each producer produces multiple resources, similar like the consumer.
3. The consumers are served on a less-demond-first-serve basis, such that at
each time the consumer

f*y2008-02-11 08:02

2 楼

这个题目貌似不太适合interview
看起来没个把个小时搞不出

each
it
at
requires

【在 l*****c 的大作中提到】

: 今天下午没事编出来个题，呵呵。
: Implement a multi-consumer multi-producer model such that:
: 1. each consumer could consume multiple resources at a time, which means each
: consumer must get a given number of resource at once. The interface of the
: consumer would look like: void consumer(int n) where n is the number of resource it
: needs at once.
: 2. each producer produces multiple resources, similar like the consumer.
: 3. The consumers are served on a less-demond-first-serve basis, such that at
: each time the consumer

l*c2008-02-11 08:02

3 楼

我是说这个如果可以搞定，那么interview的题应该不在话下了。

【在 f*******y 的大作中提到】

: 这个题目貌似不太适合interview
: 看起来没个把个小时搞不出
:
: each
: it
: at
: requires

p*o2008-02-11 08:02

4 楼

Nice problem. I need as many semaphores as consumers and one lock.
Is there any better solution?
To prove the correctness is also interesting.

each
resource it
at
requires

【在 l*****c 的大作中提到】

l*c2008-02-11 08:02

5 楼

The problem is, you don't know how many consumers are there. Actually the
number of consumers might be dynamically changing during the processing.

【在 p***o 的大作中提到】

: Nice problem. I need as many semaphores as consumers and one lock.
: Is there any better solution?
: To prove the correctness is also interesting.
:
: each
: resource it
: at
: requires

p*o2008-02-11 08:02

6 楼

That's what I mean ... You create one when entering Consumer( ) and destroy
it when leaving Consumer( ).

【在 l*****c 的大作中提到】

: The problem is, you don't know how many consumers are there. Actually the
: number of consumers might be dynamically changing during the processing.

l*c2008-02-11 08:02

7 楼

OK. I know what you mean. That works. Where is your complete solution? But I
think we only need one semaphore to count the # of consumers, no need to be
one semaphore per consumer.
I have a solution with three semaphores (but I left it at home).

destroy

【在 p***o 的大作中提到】

: That's what I mean ... You create one when entering Consumer( ) and destroy
: it when leaving Consumer( ).