Сегодня мне пришло вот такое письмо:
Просмотрев решения перечисленных участников по задаче 1951B я увидел, что все эти решения действительно полностью(или с заменой переменных) совпадают с моим, чего по чистой случайности бы не произошло. Поскольку я не давал никому свое решение, и не сохранял код в открытом доступе, это могло произойти только если один из участников заблокировал эту задачу, посмотрел мой код, и скинул его остальным.
Действительно, оказывается, в моей комнате только один участник заблокировал задачу B — _Untrackable_(никнейм говорит сам за себя). Он заблокировал эту задачу на 1:44, а если посмотреть посылки участников из списка, то видно, что многие из них ранее засылали по этой задаче код, совершенно не похожий на мой (некоторые даже на других языках!), но все они, примерно на 1:55(то есть после блокировки этой задачи), заслали ровно мой код, максимум с заменой переменных.
Такой способ читерства на контестах позволяет человеку, который отсылает всем решения остаться безнаказанным, при этом вся вина будет свалена на другого честного участника.
Прошу разобраться с этой проблемой, MikeMirzayanov.
Hi, indeed such leaks happen sometimes. I want to assure you that participants whose code was leaked by this way never get punished (and you can see it, as your submissions were not skipped) but it's not always obvious who leaked it.
Thanks for the report, we will unrate _Untrackable_ from this contest.
Hi, so the last sentence in the message isn't true (it says I could get banned)?
You won't be punished if it is your first time.
P.S: I didn't mean he's cheated, I just meant he won't be punished if he's innocent
You won't get banned for leaking through hacks, don't worry.
Why not just leave first unique solution, and discard all the copies?
I guess there are cases where the original solver also leaks the solution deliberately, in such cases it is fair to punish all of them.
Maybe it's fair, but: 1) it's hard to tell if they really had malicious intent, or just are ace5. 2) if every copied code will be guaranteed to not count, no one will want to paste it, problem solved, no?
IMO the best solution to this problem is to either disable hacks completely or have a separate short hacking session after the contest. Codeforces is the only popular competitive programming website where solutions can be compromised mid-contest very easily.
This is reinventing TopCoder I believe.
TopCoder was right all along (maybe even the weak tests are good).
Agreed. The added push to reason about your code and the chance to have a good shot at hacking was definitely enjoyable!
ex-ICPC
I guess not every contest is in ex-ICPC rules
i feel like hacking should just be completely removed.
There is no current purpose to it, 99% of hacks are not some smart case tripping up wrong greedies but a string hashing hack or umap hack etc.
if you have rooms (even after contest), it is a matter of luck (imagine losing 1st place to this, yes it has happened), if you do not have rooms, it is even more a matter of luck and just finding the wrong guy fast.
hey? i was giving contest and i received this notification. how can u put the blame on me without any proof? may be someone else have copies ur solution from the room or u have send someone( does not it means that u are high rated then u can put the blame on someone else) if u see my profile i didnot give a fkk abt rating . i only solve div2 c and d for practice and sometime e. in that contest i just wanted to check my current lvl after practicing a lot div2 d . if i am interested in cheating then my rating would have easily crossed expert.
u neither have any proof against me. just u see some low rated user and started puting all your cheating(may be somone else would have copied ur code from room) on me and use me as a scape goat to escape from cheating.
As u are high rated obviouly ur words will be given priority without any proof.
i was giving today contest and i see the notification. i was shocked to see so many of u blindly aggreing him.** is there any proof that he had not cheated ? just because he is high rated u are agreeing to him blindly . he may have leaked it ? if u see my past contest i only solve div2 c,d,e for practicing . i am not interested in rating ( u cann see it from my past contest i had solve c but then start solving d) if i have to cheat then i would i have easily crossed the pupil mark atleast.
i give contests only for fun . i did not know how blind u guys are , just because a high rated user start saying senseless thing . he may have given solution to his friends etc. and u guys agree to his statments.** he already know low rated user are scape goats for this senseless thing.
Saying "I don't even care about rating" is a really bad excuse. It's clear you don't care about rating, in fact you don't care about CP at all, but perhaps you do care about the money other cheaters pay you to give them solutions.
He doesn't care about didgnity as well
If u had some basic level of general thinking then only read the below part else u can downvote and comment senseless paragraphs like u are doing
IF I HAVE TO GET MONEY FROM CHEATERS THEN I WOULD HAVE SOLVED EVERY CONTEST FROM A THEN B THEN C ..GOING ON .. I WOULD NOT HAVE SOLVED QUESTIONS RANDOMLY.I WOULD HAVE SOLVED QUESTIONS IN A LINEAR MANNER( NOW PLSS DON'T COMMENT WHY IN LINEAR MANNER,I HAD GIVEN WARING ABOVE- IF U HAVE BASIC LEVEL OF GENERAL THINKING).
I AM NOT FOOL TO INVEST 1 HR ON PROBLEM D JUST TO GET WA 2 INSTEAD OF SOLVING A,B,C TO GET MONEY IN EVERY CONTEST
If u have any valid reason to tell me I got money from cheaters then plss reply I will be happy to know abt it . If u had seen my sumbission in the contest i had solved c then tried b then a ..if I have to get money i would easily fast solved a and started selling solution Before putting blame on some one. Have some basic level of general thinking
thats just cringe
cope imo
Actually, solving problems in different from alphabetical order is sometimes a clever thing. If problem A costs 500 points, problem B costs 1000 points but you expect to spend 7 minutes on A and 10 minutes on B, better start with B.
But if I am concerned about selling solution to CHEATERS and earning money then I would have start from a . As we never know the difficulty level of each question. Some time even b is harder and of rating 1700.
U may have seen many cheaters wo sell solution start from a .
No, if a person wants to cheat, it also might make sense to solve problem D before A, B, C. This way they can get a competitive advantage in the cheater market. A cheating acceptor can get A, B, C solutions from one cheating donor and D from another.
I solved D before A,B,C in div3/4s and regret it because the penalties add up to the point where I became lower ranked than the one who does A,B,C first and D slowly.
Yes, solving the problems in different order is not always profitable. It is profitable when a problem is harder than one of the next ones, or when it's easier but not as much easier as it is cheaper.
In your case probably D took too much time to start with this problem. Also note that you get tired after solving a hard problem earlier but still need to solve those easy problems.
You can train this exact aspect here: https://codeforces.me/blog/entry/58256
Sorry for the downvote, it was by accident. I do want to upvote.
Never mind :)
but who would pay you for a solution to ABC?
womp womp
bruh playing ratism card LMAO
This whole situation seems really funny to me, because cheater is obvious here and so many coincidental events must happen to make it possible.
At first he is the only person who blocked his submission in the room, that is already pretty improbable.
Secondly out of all participants in his room, he picked the most (or one of the most) higher rated one, but not only that, one of the known members of community. If he picked some low rated user, I am pretty sure that such person would not make investigation this big.
Then for some reason he submitted this problem really late in the contest and if, let's say, he blocked his submission at 0:15 and copied submits started at 0:30, it's fine. But 1:44 and 1:55 is not.
And finally, he did not change any of the code. It is second problem in the contest and changing even a few lines of code should be enough.
Theoretically, if I were a master and I wanted to sell my code, it would be pretty easy to make this happen. Maybe after 1:45 I saw someone locked B, so I would have an excuse when the codes coincide, and farm some positive contribution.
this exact situation was brought up before https://codeforces.me/blog/entry/108122
is it possible to block any task during the contest? i don't understand this part.
https://codeforces.me/blog/entry/107753
Bro, why isn't anyone viewing from this POV: I'm a master, who is very trusted through the community and people will believe me, I wanna make some money.
I'll solve div2 problems abcde, and when a person from my room locks that problem, I'll start selling it, so if I got code coinciding, I can just blame that random poor guy.
Bro, why isn't anyone viewing from this POV: I'm a hard-stuck newbie who is totally and completely unsucessful in life so I dropped down to cheating and selling solutions by locking problems and stealing other people's codes. Then, when I was exposed, I used my shitty alt to try and blame the other person, who's obviosly innocent, which totally worked! (spoiler: it didn't)
I guess seeing the room from Untrackable's point of view would make some sense? Maybe he opened only one code (which would be very suspicious)?