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galen_colin's blog

By galen_colin, 4 years ago, In English

In the round 702 that happened a few days ago, somehow all submissions were rejudged on all tests, which include some of the uphacks that were done after the contest's hacking phase. For example, my F retroactively changed from accepted to TLE. Maybe this has changed, but I thought the original point of uphacks were to strengthen system tests for practice, not to change the verdicts after contests finish.

I'm a bit sad about losing first place, but it was unofficial for me anyway, so that's not really the point... but, is this a permanent change in the stance on uphacking? I was only hacked because I talked with someone else (after the hacking phase, when it was supposedly final) about a case I found that would cause TLE. Will it be better to keep this sort of thing secret in the future?

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4 years ago, # |
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There are two types of uphacking, the one the influences standings, which is the case for educational rounds and Div. 3 rounds, in those there is a 24h hour window in which you can try to hack anyone and that does change the standings. There is also the "just for fun"/"educational purposes" uphacking, that you can do at any time but it does not influence official standings. In your case it was the official one.

On another note, I would like to see official uphacking phase that affects standings for every round, even Div1. Maybe that could last for 30 minutes after the round and you should be able to hack anyone. Not sure if that would be a good idea since occasionally someone is able to hack everyone, but I would like to experiment that.

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    4 years ago, # ^ |
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    My solution survived the "official" one; it was done after the hacking phase was over. The rejudge today that killed my solution happened 3 days after the contest's end.

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4 years ago, # |
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first place in my heart orz

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4 years ago, # |
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Hi. Yes, it seems there is an issue in the system: after 12h open challenge phase uphacking starts automatically, but this time I started system test later and it included uphacks also. I don't think I want to revert and rejudge it: just think about it that some other (or your) solution was hacked in time on this test. I'll try to avoid it in the future, but it will require too much effort to revert solutions, tests and ratings, rejudge solutions and apply ratings back if I decide to do it now. Sorry about it.