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kostka's blog

By kostka, 4 months ago, In English,

You asked for it and we are trying to deliver! Almost all tasks from the 22nd, 23rd and 24th Polish Olympiad in Informatics are already translated and are available on Szkopuł:

Tasks from the last edition (25th) are being translated.

Please don't be scared of Polish titles, that's because we are trying to unify all problems. The problem statements should be in English. In particular, check if your language is set to English (the flag in the upper-right corner).

Out of all 396 original tasks from all 25 editions of the Polish Olympiad in Informatics, over 83% are available in English right now. I really hope that we can reach 100% later this year to celebrate the 25th birthday of the POI, but I don't want to promise anything.

Enjoy!

 
 
 
 
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4 months ago, # |
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Great!

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4 months ago, # |
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anyone know if there are editorials for these tasks?

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    4 months ago, # ^ |
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    Unfortunately, there are detailed editorials, but only in Polish: https://oi.edu.pl/l/40/

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      4 months ago, # ^ |
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      so is there any plans to translate the editorial as well?

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        4 months ago, # ^ |
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        I'm sorry, but no. A single book in Polish is pretty problematic.

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          4 months ago, # ^ |
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          Do you know an efficient way to translate them? I used to use Google translate for PDFs because translations were nice but this is no longer possible (it says that file is too big). I also tried translating line by line but it is much much harder to understand).

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            4 months ago, # ^ |
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            Mhm... I used to translate the whole paragraphs (from Japanese) and it worked pretty well. Also, there's plenty of Poles here. Feel free to ask about any editorial and I am sure someone will answer.

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4 months ago, # |
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This is a very tremendous effort. Thank you very much!

By the way, do you plan to reveal test datas for POI 23rd and afterwards?

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    4 months ago, # ^ |
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    Just to clarify: I didn't translate them personally, I just complained about the lack of translations and uploaded them.

    As far as I know, the testcases will be published with editorials (I don't know when). If you need them right now for some particular reason, feel free to message me. I will check what can I do.

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      4 months ago, # ^ |
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      Are you intending to translate the courses ?

      Because they seem pretty good to learn from these courses ?

      What do you think ? kostka

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4 months ago, # |
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I think translation of this task is a bit incorrect. Problem statement says you can swap two adjacent cells but according to editorial arbitrary 2 cells can be swapped.

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    4 months ago, # ^ |
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    Heh, I quickly checked and it looks like you are correct. I will notify the right person and we'll change that. Thank you!

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4 months ago, # |
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Great job. Thank you!
I've been looking for them from two years ago!

It'd be great if adding problems of POI to Szkopuł could be done in nearly real-time, or even holding online-mirror contests, so students from other countries could use them as a good practice plan. Somehow like COCI or USACO.

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    4 months ago, # ^ |
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    I would like it to happen as well, but we need some manpower.

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4 months ago, # |
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Any ideas on how to solve the problem Zapiekanki from 24th POI Round 3? (according to the official results no one got a full score onsite I think and I only got the O(k3) solution)

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    4 months ago, # ^ |
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    You can find an editorial here (it is written in Polish) Editorial.

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      4 months ago, # ^ |
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      I'm not sure if I translated it correctly but it seems like the solution described here only made use of the fact that it's hard to create strong tests for this problem?

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        4 months ago, # ^ |
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        As far as i know the model solution used the fact that log n of states is sufficient. Unfortunately i cannot provide a proof. Anyway, it is not a great editorial though, sorry.

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          4 months ago, # ^ |
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          Model solution is dp in O(k2) and it doesn’t use this observation (i don’t know if it is true that logn states are enough). It uses fact that in optimal solution we have blocks where we bake without any break and this blocks ends in a moment when some clients come (there is a problem that we can’t bake before moment 0 but it is possible to change all ti < d to d and add dti to result).

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        4 months ago, # ^ |
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        Yeah, it is not an official editorial, just a bunch of smartasses think they are funny.

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A bit off-topic, but does the new POI site not support Java anymore?

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    4 months ago, # ^ |
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    No, but Java (and Python hopefully) will be supported in a near future.