descrip's blog

By descrip, history, 4 years ago, In English,

This year's Canadian Computing Competition was supposed to happen today, but it looks like it's being DDoS'd, and people can't submit to the judge. I've talked from some friends who were supposed to write today, and they said that UWaterloo has cancelled the competition. Can anyone confirm?

 
 
 
 
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4 years ago, # |
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Probably too late now, but some schools had periods of access so unfortunately some schools had people who saw the problems but weren't able to perform to the best of their abilities.

This means that the only solution to satisfy everyone at this point is to hold another contest with different problems, because if the same contest were to be held again, people who saw the problems but for whom the grader crashed half-way wouldn't be able to retake the contest (they potentially have memorized the answers, etc.).

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4 years ago, # |
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I've emailed the contest organizers, and they're currently unsure of what to do. They said that they're more concerned with fixing the judge first before deciding anything else.

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    4 years ago, # ^ |
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    They really need to make a new contest because we paid to write a fair contest.

    [Erroneous comment suggesting using CF for CCC deleted]

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      4 years ago, # ^ |
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      I don't think Codeforces is less prone to DDoS if criminals decide to do so.

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        4 years ago, # ^ |
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        Codeforces could probably easily implement a rate limiter on the judge and use Cloudflare to protect against layer 3 DDoSs. The CCC people should be able to do it too, but I have no idea what's going on with them because apparently the judge has been crippled in some way, which is not a normal symptom of a DDoS attack.

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4 years ago, # |
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Just to illustrate the gravity of the situation.

Before the online judge, CCC was marked manually by the teachers who proxied the contest. This way of judging has it's flaws: prone to error from the teachers, very time-consuming, and unequal grading (specifically time limits, and basically no memory-limits). Designing a problemset around these restrictions can be a pain in the behind.

So a few years ago, the CCC committee created the online judge and we're enforcing it more and more each year. To advance to the 2017 Canadian Olympiad, you would have to using the online judge for that year's CCC.

Well this DDOS changes everything. Not only will a whole new problemset have to created(as some students saw the problemset, from maximaxi), but this will only complicate the much needed transition to the online system. I used this judge for last year's CCC/CCO, and it sure felt a little hacked together for a contest at this scale/seriousness (we wait all year for this contest). Different results for the exact same submission, and other minor things...

I really hope the commitee can pull everything together in time

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4 years ago, # |
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Yeah, I'm one of the contestants who wrote this without the online grader this morning (outside the North America, more specifically Mainland China). The proctor told us to send the solutions to her email and they would be judged later.

p.s.: The online grader hasn't be fixed yet, at least until now (Feb.18 4:37 Utc). I feel deeply frustrated. I thought I could have 60+ easily. Just without the online grader, everything is gone.

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4 years ago, # |
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If you haven't seen them yet, here are the three main reddit threads discussing the situation on /r/uwaterloo:

  1. https://www.reddit.com/r/uwaterloo/comments/468q68/cemc_is_very_slow/
  2. https://www.reddit.com/r/uwaterloo/comments/46a3ro/will_they_redo_the_ccc_contest/
  3. https://www.reddit.com/r/uwaterloo/comments/4693ht/ccc_online_grader_is_down/

From Jacob Jackson, a problem coordinator:

At a minimum, there will be an additional qualification contest to assist in determining the attendees to the CCO. There may be other resolutions and alternative plans beyond that.
We will release an announcement with more information tonight or tomorrow.
Again, we sincerely apologize for the inconvenience and frustration caused by the DOS attack.
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4 years ago, # |
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Can someone explain the solution of the fifth problem, Combining Rice Balls?