10697 - Firemen barracks

liulike · Post by **liulike** » Thu Aug 26, 2004 5:25 pm

Could some one give me some I/O ?

Thx a lot!

Observer · Post by **Observer** » Fri Aug 27, 2004 8:35 am

I get WA too... Hope it's not another Pascal-unsolvable task. (Remember 10215 Largest-Smallest Box?!)

Could anyone tell me how I am supposed to round the numbers, especially negative ones? Thanks in advance.

Btw, might there be "-0.0" problems? I've considered that, but still, no luck~

little joey · Post by **little joey** » Fri Aug 27, 2004 11:29 am

I don't think it's a Pascal problem, because my C program can't get accepted too.
The number of submissions is now 110 (and steadily rising) and there's only one accepted (is he the problemsetter?).
Because this is a relatively simple problem, the chance that something is wrong with the I/O is reasonable. During the contest there were problems with this problem; looks like they still exist...

Krzysztof Duleba · Post by **Krzysztof Duleba** » Fri Aug 27, 2004 2:32 pm

I tried to do this problem during the contest. It took me an hour and many submissions to realize that the fault is not on my side. I wonder if anybody will be able to solve it at all (a guy that probably is the problemsetter himself doesn't count).

Observer · Post by **Observer** » Fri Aug 27, 2004 4:31 pm

little joey wrote:During the contest there were problems with this problem; looks like they still exist...

Is that so?! I didn't join the contest, so......

What're the problems anyway?

Per · Post by **Per** » Fri Aug 27, 2004 5:56 pm

It's not the problemsetter, the problem actually has been rejudged since the contest. With the new data, there were 3 AC submissions during the contest rather than just the problemsetter (still compared to something like 250 WAs though), but all those AC submissions seems to be by Brazilian people who participated in the contest "on site", so perhaps the contest judges simply based the new data on one of those peoples incorrect solution.

sergio · Post by **sergio** » Fri Aug 27, 2004 8:43 pm

Hi!
I am one of the problemsetters of this problem. As during the contest we noted that nobody was getting accept in this problem, so after the contest I took some source codes from people in our university and changed some inputs which can produce a float point error. So after this we were expecting that everybody can get accept in this problem, but seems there are float point errors yet.
We will develop a special correction program to judge this problem. I will post here when we finish this program.

S

sergio · Post by **sergio** » Wed Sep 01, 2004 9:51 pm

I sent the special corretor program to UVA this Monday (08/30). I think they are a little bit busy now, so lets wait a few days and they should rejudge the submissions in this problem

liulike · Post by **liulike** » Thu Sep 02, 2004 10:11 am

from this page:
http://acm.uva.es/problemset/rejudge.php

I saw that the problem has been rejudged on 08/31/04.

There's still only one accepted

It's a little strange

sergio · Post by **sergio** » Thu Sep 02, 2004 1:42 pm

So, I think we have a problem now

I will post some test cases here, so we can compare our answers:

INPUT

10
0.3 0.4 0.3 0.4 1.1 0.7
2.1 23.4 5.9 0.3 4.5 -2.0
1.0 0.0 0.2 0.8 0.1 0.9
8.2 -1.7 5.4 3.0 -4.0 15.1
7.2 3.5 5.2 9.3 0.7 8.2
-7.2 -3.4 6.3 9.7 -9.0 5.4
1.9 8.4 0.4 1.9 0.4 1.9
8.1 -0.2 0.5 1.9 2.3 2.4
6.0 4.3 2.9 0.1 -4.4 6.7
0.6 1.2 0.6 1.2 7.8 1.4

OUTPUT
There is an infinity of possible locations.
The equidistant location is (-11.5, 9.3).
There is no possible location.
The equidistant location is (-65.7, -42.6).
The equidistant location is (3.7, 5.5).
The equidistant location is (0.0, 2.7).
There is an infinity of possible locations.
The equidistant location is (3.0, -3.7).
The equidistant location is (0.7, 5.0).
There is an infinity of possible locations.

little joey · Post by **little joey** » Thu Sep 02, 2004 2:23 pm

Same answers.

I'll temporarily give my (WA) code:
[c]AC now
[/c]
Hope you can spot the differences...

sergio · Post by **sergio** » Thu Sep 02, 2004 2:56 pm

Hi!

During the contest, we changed the problem description, so a answer (-0.0, 2.0) should be (0.0, 2.0) and the output should not have a coordinated -0.0.
I compared the outputs and I think this is the problem, look the cases below:

2
0.1 1.2 1.3 0.4 0.2 1.2
0.0 0.8 0.6 2.4 0.9 1.6

The equidistant location is (0.2, -0.0).
The equidistant location is (-0.0, 1.7).

Try to fix this and resubmit your code or post it again.

S

little joey · Post by **little joey** » Thu Sep 02, 2004 3:05 pm

Yep, got AC now. But don't you think the special judge should accept -0.0? Or at least the problem description should mention that -0.0 is not acceptable IMHO.

sergio · Post by **sergio** » Thu Sep 02, 2004 3:12 pm

During the contest the explanation about the -0.0 was given, but it is really missing now

I will try to change the problem description and send it to the UVA.
I got AC too

little joey · Post by **little joey** » Thu Sep 02, 2004 3:27 pm

Hmm. I would opt to change the special judge. I think programming problems should concentrate on solving programming questions, not on how a particular compiler in a particular environment prints numbers. But that's only a point of view...