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PavelKunyavskiy's blog

By PavelKunyavskiy, history, 4 days ago, In English,
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By PavelKunyavskiy, history, 4 years ago, In English,

Everyone on this site heard about problem preparing tool, maintained by MikeMirzayanov called polygon.

It have a lot of advantages, like automatic checks of everything you can imagine. But also, it have several very annoying things. The main one for me is necessity of synchronizing solutions and generators files by hand, between polygon and your local copy. So I had written a tool, which can do it.

Tool is published on github, with instructions how to install it. You are welcome with any new features/suggestions (I'm not knowing python very well, to be honest).

Known problems:

  • Not tested good enough, probably buggy
  • Installation script working strange. Anyone knowing python better? Any better ways to distribute?
  • Sometimes lost of session is not detected and script fails with strange non-readable errors. relogin helps
  • Parsing html pages can be not stable enough with changing polygon. Waiting for better api from MikeMirzayanov and codeforces team.

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By PavelKunyavskiy, 5 years ago, In English,

Two years ago (or something like that) GCJ problemsetters announced commandline-tool, which can download input, make submissions, and view current contest state. It support was not very long, but before last contest it worked as is (at least downloading and submitting).

Before last contest I discovered, it can't login to google account because it get HTTP 404 error. Any ideas what got wrong and how to fix it?

Also I'm interested if anyone else, except me, use it?

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By PavelKunyavskiy, 6 years ago, In English,

Good time of the day.

As some of you know, yeputons and I have an archive of IOI-tasks. While preparing it, we had understood, that we have no resources to prepare graders for all languages,so we want to find a way to write a grader only for C, and to link other languages to it.. Also, I think it's better to have one grader and adapters to avoid code duplicating, which can cause errors.

There were some problems with linking Pascal, but they were mostly solved. I'll write about one unsolved problem further. It would be very good if someone have ideas how to solve it.

Next year Java will be available on IOI. So I tried to write Java adapter for graders. Here is one for the problem 2010.cluedo. I think this one works well.

I publish this because I think someone else can be interested in it. Also I have some problems, which I don't know how to solve. Probably someone here can solve them.

First of all, we need to include jni.h. But it doesn't belong to gcc library path. So we need to set path, which depends on computer settings (path to java, to be more precise).
Also this way is quite complicated to compile. I don't know how to do this in some IDE, which is probably used by participant using java. And participant probably don't know what is jni, and how to do something like this.
The same problem happens to pascal. Also there is one extra problem. FPC needs libc to link this. And I don't know way to find libc on windows. libmsvcrt.a from MinGW is ok. But how to find it on participants computer? And what to do, if he is using some other compiler? Also, participant needs C-compiler to use Pascal, and that is not very good.

All this problems are not really important on competition (as we know settings of participants computers), but if we use on-line judge for it we will face the above-mentioned problems.

I hope there is someone from ISC or some other IOI structures, who can help with it, who is reading Codeforces. Anyway, if you have some ideas how to make this better, or any comments, I will be very interested in it.

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By PavelKunyavskiy, 6 years ago, translation, In English,

Topcoder SRM 600 will be held next Saturday in 21:00 MSK

On round they promise 120 t-shirts for Div.1 and 40 t-shirts for Div.2, half for top ranked, and half the participants randomly chosen among having more zero points.

But that's not all. On Sunday 21:00 MSK there will be held non-rated SRM 600.5 (Special Round Match). Where there will be 40 more t-shits and 600$ prize for first place. Round will have duration of 4 hours and consists of two tasks, which did not give on-sight TCO as too complex and one Div1-Hard level. Besides the top 40 with a nonzero score promise 10 t-shirts for random spectators (people who were logged in the arena more than 3 hours of 4).

UPD: Since this match TL and ML are indicated in the problem. The authors say that they will try to use TL 2 seconds and ML 256 MB for most porblems. (used to be 64MB)

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By PavelKunyavskiy, 8 years ago, translation, In English,

Hello!

We are happy to invite you to participate in today's round. I hope everyone will find interesting problems for him. And most of the round participants will like it as well as the previous one.

Today's contest was prepared for you by SPb SU 4 team (Alex-Gran (Alexandr Granovskiy), Dmitry_Egorov (Dmitry Egorov), kuniavski (Pavel Kunyavskiy)). After long thoughts you can notice that we present St.Petersburg State University.

Thanks very much for help in the tasks preparation to Artem Rakhov(RAD), Gerald Agapov (Gerald) and Maria Belova (Delinur) for translation statements. Also thanks to Petr Kalinin (KAP) for statements proofreading.

In today's contest there will be seven problems (5 in each division) about the country where wizards live, and this causes many interesting events. Today you have to take part in local meeting, understand the intricacies of writing spells, ride on the magic transport, try to take away magic prizes, play in popular wizards game, help magic government in ruling the country and resolve financial dispute of two famous wizards.

Scoring is standard is standard in both divisions today (500-1000-1500-2000-2500).

UPD: analyse was published.

Good luck!

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