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Cheating during CF Educational Round 100
By generic_placeholder_name, history, 4 years ago, In English

I am pretty sure that during Educational Codeforces Round 100 (Rated for Div. 2), buihoatpt2k3 copied code from huyhoangk36chv.

buihoatpt2k3's behavior is quite suspicious in general — he (?) submitted all his code during the last 30 minutes, and his code is heavily obfuscated.

We see, however, that after running the preprocessor (gcc -E) on the code, we get code that is strikingly similar to that of huyhoangk36chv.

For example, take 1463A - Dungeon. Here's huyhoangk36chv's code: 101515478. And here's the de-obfuscated code from buihoatpt2k3: 101775980.

Same deal for problem D: 101562763, 101776426.

I think this is pretty good evidence that these users cheated and copied code from each other, and as such, call for their participation in the contest to be voided.

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4 years ago, # |
  Vote: I like it +63 Vote: I do not like it

It is forbidden to obfuscate the solution code as well as create obstacles for its reading and understanding. That is, it is forbidden to use any special techniques aimed at making the code difficult to read and understand the principle of its work.

Protip: At least put some efforts into reading the rules if you wanna cheat.

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    4 years ago, # ^ |
      Vote: I like it +38 Vote: I do not like it

    Yes, it is quite amazing.

    Another thing? The two are placed right next to each other in the rankings. Talk about being impossible to miss.

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    4 years ago, # ^ |
      Vote: I like it -109 Vote: I do not like it

    can we use VietNamese here :))))

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    4 years ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    one probably gave no f**k about the rules if he wanted to cheat anyway

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4 years ago, # |
  Vote: I like it +46 Vote: I do not like it

After some research, it seems that he usually submit all of the problems after the 1-hour-mark. Also, he has the suspicious #define lines that appear in some of his submissions, but not all. It seems that he has been cheating for a while, not only in Edu Round #100.

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4 years ago, # |
  Vote: I like it -9 Vote: I do not like it

And he is a master, what should I interpret. disgusting......

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    4 years ago, # ^ |
      Vote: I like it +67 Vote: I do not like it

    Masters are just as susceptible to cheating as green's and grey's. How do you think... never mind

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4 years ago, # |
  Vote: I like it +172 Vote: I do not like it

This guy cheated before multiple times. I just banned his account.

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    4 years ago, # ^ |
      Vote: I like it +24 Vote: I do not like it

    Hi MikeMirzayanov, here's another possible cheating case in edu round 100.

    101523572 and 101524494 are the user's submissions for B and D, they are only 1 minute away and of completely different coding styles. E.g., one surrounds signs with spaces but the other doesn't, one uses endl and the other uses '\n' etc.

    Also 100012744 and 100014591 from edu round 99, same user same issue.

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    4 years ago, # ^ |
    ← Rev. 3   Vote: I like it +4 Vote: I do not like it

    caoyizhong cheated in round 688 div2 standings problem F 100365572, because the code head is different from all his other submissions and the time of submission is irregular. For this he get the 1st standing.

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      4 years ago, # ^ |
        Vote: I like it 0 Vote: I do not like it

      Thx, but thats because I have exercised a similar problem and modified the std before.I think I am admitted to use it. In fact, i am the first people to accept it.

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