333 - Recognizing Good ISBNs

Caesum · Post by **Caesum** » Sat Jul 13, 2002 12:02 pm

Yes, I made a few attempts, looked up the correct definition of ISBN and relaxed some rules and tightened others, no progress though...... It would be nice to get more feedback from the people that make these changes sometimes.

xenon · Post by **xenon** » Sat Jul 13, 2002 12:38 pm

I couldn't agree more.
I saw Picard was on the hunt too, so I guess we'll get some answers soon

Ivor · Post by **Ivor** » Sat Jul 13, 2002 1:02 pm

I haven't solved this problem, but I just want to ask a question. Has anyone tried reading a whole input at a time? I'm just curious to know how long does it take? Somehow I have a feeling that this accepted guy has not been rejudged. Have you thought how 104 zero time was possible? I have and the only conclusion I have, is that in 104 you can't read even data in zero time -- my best was 0.010. So maybe they have some 'holes' in rejudging and the whole 333 input data is bad and it is not your problem that you cannot get it accepted.

Ivor

Caesum · Post by **Caesum** » Sat Jul 13, 2002 1:04 pm

hmm...... i am wondering if the people that solved 168 have been rejudged too

Ivan Golubev · Post by **Ivan Golubev** » Sat Jul 13, 2002 1:20 pm

After some rejudgement there was a problem with several AC results but there were nobody in ranklist!

xenon · Post by **xenon** » Sat Jul 13, 2002 1:31 pm

He he, 168 is our old friend the Minotaur, isn't it?

Re 333, I've been able to deduct, with reasonable certainty that:

1. The input contains empty line(s);
2. There are no lines with just space-chars;
3. There are no cases where space-chars are the only illegal chars in an otherwise legal ISBN (legal according to the previously accepted algo);
4. There are ISBDs with more than one X.

I tried the four ACCEPT/REJECT combinations on 1 and 4, but they all turn out WA

Waiting in despair,
-xenon

PS. Ivor, you got an interesting point. I just tried it and the program took 0.120 seconds to run, just reading input! So there must be tricks to fool the judge.

Ivor · Post by **Ivor** » Sat Jul 13, 2002 1:41 pm

I don't believe there is a way to fool the judge in that way but there are tricks. For example you can use far more memory than 32M, but only if your program is fast enough to finish within 0.080/0.090 seconds.

I found it some days ago, but I didn't fit within this limit.

But I do believe it's due to rejudging. Maybe they have some bugs in their rejudging program?

Ivor

Caesum · Post by **Caesum** » Wed Jul 17, 2002 8:06 pm

finally i got my rejudgement email which went back over several rejudgements and some were from May!!!!!

Dominik Michniewski · Thu Jul 18, 2002 12:50 pm

I'm really frustrated on this problem ....
I found one more problem with ISBN's - is number starting with hyphen correct? And what should I print if line has only white spaces ?
And finally - tab character is legal or illegal ? And what about white spaces inside of ISBN ?
Maybe anyone has any idea about that ?

Greetings
Dominik

Caesum · Post by **Caesum** » Thu Jul 18, 2002 6:39 pm

since noone appears to have an AC i doubt if anyone can help........ but when i was looking into isbn's spaces as well as hyphens are legal, however this does not get you an AC.

Dominik Michniewski · Thu Jul 25, 2002 11:21 am

I don't think, that only one person know how to solve problem 333 .... it's very strange situation for me ....
Maybe this problem needs some RE-REJUDGEMENT ??

Ivan Golubev · Post by **Ivan Golubev** » Thu Jul 25, 2002 11:28 am

Not "maybe" -- it's definitely needs rejudgement. So just relax and forget about this problem now.

...Just interesting, anybody wrote message to judge team about this problem?

Dominik Michniewski · Thu Jul 25, 2002 12:42 pm

I think about that, but I notice a long time ago judge about problems with another problem (139 in fact) and I got response, that all's OK ... after that - 2 weeks later maybe - rejudgement was occurred adn I got Accepted

)
I try to notice judges about 333 today afternoon ....

but btw. I think that somebody just did it

))

Caesum · Post by **Caesum** » Thu Jul 25, 2002 6:41 pm

I am amazed that they change things and get it rejudged and do not bother to check the result of what they did !!!!!!!!!!!

Dominik Michniewski · Thu Aug 08, 2002 12:19 pm

I saw, that many people has this problem now accepted !
Could anyone say me, what's changing in online judge input data ???