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skywalkert's blog

By skywalkert, 2 weeks ago, In English,

Hello!

This weekend we would like to share an online-mirror of 2018-2019 ACM-ICPC, Asia Xuzhou Regional Contest with you. Please notice its start time is Saturday, December 1, 2018 at 18:00 (UTC+8) and we will be there for answering your questions. You are able to register 6 hours before the contest starts. However, before the registration starts, you may not view this contest on Gym. After the online-mirror contest, you can virtually participate at any time you want.

The 2018 ACM-ICPC Asia Xuzhou Regional Contest has been finished at China University of Mining and Technology, on October 28. Although 288 teams participated in the onsite contest, only 195 of them (including invited teams) finally solved at least one of 13 problems in 5 hours. Is the contest too hard? Or is the difficulty only applied to Chinese participants? We cannot get a conclusion clearly... Anyway, we hope these problems will benefit people who want to gain great results in ICPC.

The problems are prepared by AHdoc, Claris, quailty and me. Thanks to niike0goood and zscc for discussing ideas, yefllower and niike0goood for testing, Syloviaely for playing a crucial role in the contest, and MikeMirzayanov for developing Codeforces and Polygon.

Also, as a kindly reminder, Jisuanke will hold another online-mirror contest that will start on Sunday, December 2, 2018 at 12:00 (UTC+8).

We kindly ask everybody who has already read the problems not to participate this online-mirror contest or discuss any solution in public before the contest has ended. Your cooperation will be greatly appreciated.


UPD1: Registration starts. You may view this page to register.

 
 
 
 
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2 weeks ago, # |
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Today’s suspense: whether Red Fanta can AK this contest.

(And whether they can solve 4 more problems than the onsite champion again

The tasks are interesting, and I hope you will enjoy this contest :P

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10 days ago, # |
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Is there no option to ignore redundant spaces? I had to remove redundant space after solution for getting AC on H.

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    10 days ago, # ^ |
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    Yes, unlike many problems in Codeforces, additional trailing whitespaces in one line (except the last line) may cause 'Presentation Error' 'Wrong Answer' in this problem. Each checker in this contest would check participants' output format a bit strictly.

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9 days ago, # |
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Will there be editorial for this contest?XD

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    9 days ago, # ^ |
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    Sorry, no official tutorial would be provided. We encourage you to share your experience and discuss solutions after contests. It is better than that we provide solution sketches directly.

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      9 days ago, # ^ |
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      What about random people who try it for training years later? Are they supposed to bother strangers with "hey can you give me a hint for this problem you solved years ago?"

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        9 days ago, # ^ |
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        Several problems may have multiple acceptable solutions. We think it is better that solutions are discovered by participants and we don't want to mislead anyone by official tutorials.

        Besides, asian regional contests usually do not require solution sketches in onsite events. For Xuzhou, we haven't write any tutorials.

        However, we published this online-mirror contest with solutions, so coaches are able to get authors' codes on Gym, as many coaches know.

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          9 days ago, # ^ |
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          You're missing an important thing: imperfect competitive programmers exist. What about people who can't discover some solution by themselves? What about people who don't have coach mode in Gym, for example because they don't compete in CF much?

          Too little handholding is as bad as too much handholding. In the end, the people you help by this are those who don't need it, since they can solve the problems by themselves anyway.

          I'm not even talking about full solutions, short hints would often help a lot.

          we don't want to mislead anyone by official tutorials

          Then you should start campaigning for other contests to not provide tutorials, since they're so bad and misleading.

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            8 days ago, # ^ |
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            I agree. And reading authors' code is definitely not as good as providing some hints, because reading the code and getting the idea behind it is usually time-consuming and unrewarding, especially when the solution code has a terrible coding style and no comments.

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            8 days ago, # ^ |
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            To Xellos and ultmaster,

            Personally, I strongly object to getting ideas by reading standard solutions. I just want to say it exists (not suggests), if someone has a coach mode after confirming terms to protect sportsmanship.

            As you said, we may overestimate the level of participants and underestimate the eagerness of people from this community to solve these problems.

            If needed, we are willing to give some hints. But we would do it unofficially, since some authors are busy now and we have less time to review what we would publish additionally... That is why I said our bad official tutorial, if published, would mislead people.

            Btw, is my poor English misleading you? :P

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              7 days ago, # ^ |
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              Your English is fine, it's that you're advocating for bad practice: making it harder for people to train. Doesn't even matter if it's on purpose.

              I honestly don't know if you'll actually have a lot of people who would have benefited from an editorial trying to upsolve this contest, but just put yourself in the shoes of someone like that: you failed to solve a hard problem in-contest, discussed with teammates and have no idea why you're getting WA, or just how to solve it at all. You look for an editorial — nothing. Maybe, just maybe, you find this blog post and find out that you should ask someone... but who exactly?

              This seems like way too much effort for just wanting to find out how to solve a problem (or compare your solution to the official one, even).

              If you don't have time to do it right now (idk how there's no time to write and review a few sentences, do the problemsetters get sent back to coal mines immediately after the contest or something?), then you can just say "short hints will be published later" and avoid all this trouble. But publishing things is important for one reason: it means much less time is wasted with every single person having to individually ask after things.

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                7 days ago, # ^ |
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                There are lot of kind people who writes editorial, but it doesn't mean they are obliged to do so

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                  7 days ago, # ^ |
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                  The claim here is that not writing an editorial will benefit people more than writing it. If the answer was "too bad, we don't want to", I'd shrug and move on — but it's not, so stop acting like it is.