beaaaan's blog

The very first red LLM cheater?
By beaaaan, history, 13 months ago, In English

Let me introduce you to lequoctran181 a.k.a Lê Trần Quốc Anh, a shining star in the competitive programming community from National Economics University, Hanoi. He is a philosopher who talks about CP-ing quite a lot on his Facebook page, sharing tips, talking about his journey, etc...

I admit, he is skilled, but not at cp, but at cheating. The first time I paid attention to this account was in December of 2024, where he had 2 different templates, submitting C and D only around 10 minutes apart from each other, and achieving rank 35 on Educational Codeforces Round 172 (Rated for Div. 2), notice how he didn't space down, and the different way of naming variables:

Now, after this "achievement", of course, he would be very proud, as seen bragging about it here on the blog post of the round:

You can see this man is very egoistical individual, achieving CM through cheating, then proceeding to mock other contestants who were not able to do C, I confronted him about his different code styles, in which he gave me a reply:

However, is this really true? Does he really just have many templates saved on his computer that he would switch between them in between problems? Or is there more to this?

Well, let's take a look at his recent rounds, specifically Codeforces Round 1007 (Div. 2). Before I talk further about this, I would like to talk more about one of his ICPC teammate, Hà Quang Minh, who's also known as haminh1092005, or hqm1609 (both of these accounts are disabled in contests due to obviously cheating). Now, Mr. Minh here is a very close friend of Mr. Anh, this is pretty obvious because of how many posts on his Facebook profile where he mentioned Mr. Minh:

Now, what did Mr. Minh do in Codeforces Round 1007 (Div. 2), which also got him banned? That's a great question! He solved ABCD1D2 in just under 30 minutes! that's even faster than ksun48 :O, so how did that happen? Well, the answer is AI. Let's take a closer look at his submissions which got him banned:

Looking at this, some of you might say that this code looks completely normal! And I would almost have agreed, until I noticed some discrepancies:

  1. Problem A included iostream instead of bits/stdc++.h, like every other submissions

  2. unordered_map was used on problem D2, any seasoned competitive programmer would know better than to do this, in fact, this unordered_map was not needed at all.

  3. The ways of naming variables resembles very closely to that of o3-mini.

That is too much of a coincidence, so I have came to a conclusion that this guy had sloppily edited the code which ChatGPT gave him, which got him caught, and eventually banned. Now, let's check on our friend lequoctran181, note that he started nearly one hour after the contest had started, and started with problem D1 and D2. But still, this could still be normal, he could've spent that nearly whole hour dedicating to doing just those two

But wait... what's this?

It's the exact same code that the user haminh1092005 had submitted with very little changes in variable names! What the hell? So this user is both multi-accounting and using LLM?

You're telling me someone who actually knows what they're doing is naming their variables like this? come on now, I would rather believe in Santa!

Fast forward to the present, today, on Teza Round 1 (Codeforces Round 1015, Div. 1 + Div. 2), lequoctran181 has had an extraordinary performance, solving ABCDEG1, which is equivalent to about ~2600 performance, and will get him to red after the rating changes happens, Let's check his code!

First, on problem C:

unordered_map, again! I guess he didn't learn his lesson, despite saying that he would here :(, or maybe, he didn't even know what ChatGPT was giving him?

Now, C was only submitted 6 minutes after D, and his solution in 160 lines long! He must be a very fast coder! Now, let's take a look at his submission on problem E, on which he once again used unordered_map, guess he still didn't learn...

Lastly, he submitted G1 at near the end of the contest, do you guys think he also used his "magic" here? leave a comment and let me know below!

This is all I have. Before I go, take this lovely picture of the NEU.Newbies team standing together, which consists of the 2 cheaters and their teammate celebrating their performance in ICPC Hanoi National

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Comments Comments (86)
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13 months ago, hide # |
 
Vote: I like it +2 Vote: I do not like it

PeruvianCartel what do you think?

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13 months ago, hide # |
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Vote: I like it 0 Vote: I do not like it

case closed 314095874


long long solve(int x, int y)
{
    return (long long)x * 1000000LL + y;
}
            ...
        int x = temp / 1000000;
        int y = temp % 1000000;
        if(x == y) continue;
        long long rev =solve(y, x);
            ...

(temp is 2e5 at most)

Edit: this code actually does something mb, it is just very unintuivite to code it like this.

also found this funny looking change!

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13 months ago, hide # |
 
Vote: I like it +60 Vote: I do not like it

Absolute Cinema

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13 months ago, hide # |
 
Vote: I like it +14 Vote: I do not like it

I don't get it what people get by faking their achievements and how do they live in that delusion of being good while all they know is how to cheat.

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    13 months ago, hide # ^ |
     
    Vote: I like it +18 Vote: I do not like it

    Being good is the least of his concern at this point, I'm afraid.

    It seems clear that he wants publicity. For exactly what reason, I don't know. Maybe to get his way into certain positions? Maybe to sell courses?

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13 months ago, hide # |
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Vote: I like it -17 Vote: I do not like it

[deleted]

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13 months ago, hide # |
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Vote: I like it +168 Vote: I do not like it

Update: lequoctran181 is now officially red! everyone congratulate him!

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13 months ago, hide # |
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Vote: I like it -520 Vote: I do not like it

Hi, this is me speaking now.

First of all, I have no other words to comment about the past few months. All my feelings and excitement for Codeforces, it is pure and real. Every day I get up, one of the first things that I do is to log in into Codeforces and read the "blog" section. Surely made my day, the people here are fantastic.

I understand what all of you are mentioning, and you could see that 99% of the AI users will "fight back" through comments after being accused. Of course, AI is AI and it is really easy to know that whether someone is participating genuine or not.

No further details, this is my word: "I do use Artificial Intelligence in some of my problems while solving. I felt that I don't want to lie to myself or to all of the users if they get hurt from what I was doing.

Of course, there is no excuse that could make me even 1% right. I'm wrong, I'm really wrong. It's 2AM in my country now, I feel so guilty and so bad that I have to get up and post my final message here. In the first tens of contests, I joined without using any AI. At that time, I thought that I had to practice really hard if I want to move further to ICPC APAC 2025. At some time, I reached 1600. Till now, I still believe that I am around 1700-1800.

But of course, that isn't enough to move on. So I remembered this deeply: "if I want to join the contest next year, I have to be well-prepared for the contest next year". I felt terrible that this is when I started coming the wrong path.

It all starts when I want to organize my own contest. For real, actually now I have 25 problems ready to be released in a contest. At that moment, I thought "will someone believed in my skills if I'm only 1600 likewise". That is when I started using LLM. I solved the problems fast with multiple lines of code, that is what I can really do. I would never thought I came deep as a mistake like this.

I know that no one wants to forgive what I have done. But please, I want to have a redemption. I really love competitive programming, it means the world to me know. After this post for 12 hours, I will delete my account and I will rest and criticize myself for a time, probably about a month, for how wrong have I been to the community and the amazing people here. After that, please in the deepest of my heart, I want to open another account in which I will promise I joined every single round, every single problem with integrity and always learning to achieve better performance and awards. I beg you all, can you give me an only chance to really redeem what I had did?

I know that with this, my project of problem setting must be cancelled. But if I am able to have a last chance to join the rounds with dignity, one final last chance, I promise I will never violate any single rule here. beaaaan, I really want you to offer me one more chance so that I would further improve my skills. I will create a new account and start all over, with only passion and integrity.

I wish all of you the best of health, may peace always stays with you. In the next 12 hours, if you have any questions, please fell free to ask me. I will answer all of the questions honestly, Really, really sorry, for everything.

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    13 months ago, hide # ^ |
     
    Vote: I like it +35 Vote: I do not like it

    The message is okay but by the time you become a Grandmaster, it's too late.

    I suggest you to open a new acc :D

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      13 months ago, hide # ^ |
       
      Vote: I like it -47 Vote: I do not like it

      I will definitely do that and I will erase everything I have done in this account till now. I know it is too late and it could be asking too much, but please, I only need a chance. Please offer me a chance and I promise I will never ever do anything wrong in competitive programming again.

      It's 3AM now, I will still be on in the account for the last hours to answer everything the community asks. If I can't delete the account manually, I will type a long random password and change the account's password, and never use this account again.

      Once again, thank you for reading my comments, and sorry to the most :(

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    13 months ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    what was the point of cheating?

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      13 months ago, hide # ^ |
       
      Vote: I like it -50 Vote: I do not like it

      When I first use third parties, I remind to myself that "just this one task, it would be fine...". I am shocked of how many "just one more task, I want to have more rating to make up my own problem and was recognized" thoughts I have had... I mean, after this post was published, I thought deeply for 20 minutes and realized how far of being wrong I have gone :(

      Using AI is like drugs, if I don't bet my integrity, I felt that I will never come out of it. I have been using prompts for about 2 months, after I finish competing in ICPC in December. But as I know my bad tempers now, I will never let this happen again.

      For others, I think there may be many reasons for cheating. But sitting in the wrong direction, I think most of the user wants there rating to be large, as "high ratings" is simply the more preferable choice than "low ratings".

      Once again, I apologize and I have deeply recognized my mistake. Please forgive me and please give me a chance.

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    13 months ago, hide # ^ |
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    Vote: I like it +45 Vote: I do not like it

    So if beaaaan hasn't found out you cheated, you will still use AI in future contests. Correct? imo he posted this message not because he actually wants to quit cheating, because if he does, he would have quitted it a long time ago

    UPD: I re-read the blog, and saw his comments on becoming CM and stuff. I mean, if you were to cheat and become CM, WHY WOULD U EVEN BRAG ABOUT IT???

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      13 months ago, hide # ^ |
       
      Vote: I like it -63 Vote: I do not like it

      This is dangerous and I can't deny. I have to rethink really deeply in the past hours, and I only realized how far this has gone. Before that, I think "Everyone uses it now, if I don't use it, maybe I'll get negative delta". I love competitive programming, but my childish behaviour has covered my eyes for the past two months.

      I just need a belief. I want to prove that I am a good person, and I want to be the first person to deeply understands my faults in the deepest way. Please give me a chance to redo my programming hobby. From the bottom of my heart, I will never ever do such behaviours again.

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    13 months ago, hide # ^ |
     
    Vote: I like it +4 Vote: I do not like it

    ICPC APAC is an insane place where there is no room for cheaters. These contestants tend to have at least national OI/MO TST level of caliber. I hope you understand your goals.

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      13 months ago, hide # ^ |
       
      Vote: I like it +16 Vote: I do not like it

      I surely will understand and try the hardest for my goals. I am currently spending hours a day to practice problems and learn new techniques.

      I believe that genuine, integrity and hard work will pay off. Please give me another chance and I will not let the community down in every action I do.

      P/s: I will be using this as my new account. Please give me, just one final chance. I will train with maximum effort in order to be able to participate in ICPC contests in the future. I deeply realized my problems and terrible mistakes now.

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        13 months ago, hide # ^ |
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        All the s**t you wrote above sounded like the community cares much about a stupid cheater like you seeking atonement. Let me tell you a truth: we do not. Codeforces will be indeed a much better place without you and your words. So take your ban and get away from here. Your actions now is against the Codeforces Single Account Policy.

        Sir MikeMirzayanov, I wonder if this guy deserves a ban, as making a new account to evade a ban is strictly against the single account policy.

        Shut up, Newbie.

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        13 months ago, hide # ^ |
         
        Vote: I like it +5 Vote: I do not like it

        Too late, youngster. At least true noobs can get some sorts of bouncing back.

        I could guarantee that in a serious academic environment, soulless kinds of yours deserve no redemption.

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          13 months ago, hide # ^ |
           
          Vote: I like it -8 Vote: I do not like it

          He was a noob tho. 3 problems in ICPC National is crazy work

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            13 months ago, hide # ^ |
             
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            Hey, at least if he were merely a noob he would still have some dignity left. I meant, I'm fine with people doing complete bollocks in a contest as long as that's how they genuinely are (though I'd be way less cool if those were participants under my own umbrella xd).

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    13 months ago, hide # ^ |
     
    Vote: I like it +8 Vote: I do not like it

    Did you really become GM with the help of AI? Has AI really gone that far? Or am I missing something?

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    13 months ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    Yo get rekt dude

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    13 months ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    TL;DR

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    13 months ago, hide # ^ |
     
    Vote: I like it +30 Vote: I do not like it

    skibdi

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    13 months ago, hide # ^ |
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    But please, I want to have a redemption

    Nope. Request complete in 0.01s

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13 months ago, hide # |
 
Vote: I like it +4 Vote: I do not like it

beaaaan ur my hero

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13 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

salute to https://mirror.codeforces.com/profile/beaaaan

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13 months ago, hide # |
 
Vote: I like it +2 Vote: I do not like it

Yay, he got banned

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13 months ago, hide # |
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I think it's sad that AI is "corrupting" a lot of people nowadays. Why would you have to study chess (to an expert level) if there's an AI in your pocket that's capable of beating Magnus Carlsen? The same thing goes for CP.

The thing that makes me scared the most is the fact that with AI, many students actually use it to finish all of their work and fool teachers instead of actually learning new things. It could lead to an unskill generation of coders, which should be harmful.

A student argued with me about why we have to learn how to program if there is an AI to do that for us. I mean, plug-everything-from-an-AI-without-understanding-anything is not a great thing to do =)))

(P/s: sorry for my bad English)

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    13 months ago, hide # ^ |
     
    Vote: I like it +57 Vote: I do not like it

    not just coding but... anything in general. Why would you learn creative writing or things like that for years, when ChatGPT 4o is so accessible? Like yeah, it cannot beat the top 5%, but spending years perfecting your craft, while others can just chug out 7/10 contents hourly doesn't sounds very appealing to me.

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13 months ago, hide # |
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I think i fell in love with beaaaan

Also update: not only this guy lequoctran181 was banned, but he also locked his Facebook profile.

I wonder why

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13 months ago, hide # |
 
Vote: I like it +1 Vote: I do not like it

What's wrong using unordered_map?

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    13 months ago, hide # ^ |
     
    Vote: I like it +3 Vote: I do not like it

    For some intended test cases, your solution could be TLE.

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    13 months ago, hide # ^ |
     
    Vote: I like it 0 Vote: I do not like it

    There are advanced skills to blow up all solution using unordered_map without good extend hash functions that often with mt19937 and chrono,In fact even the hash is good,it often visit $$$n / p(10000 \le p \le 20000)$$$ elements in average,That might be not good in solving tasks.In summary,you may think twice before using it as a useful array.

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    13 months ago, hide # ^ |
     
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    Hash conflicts are easily made for unordered_map in C++, making its time complexity from O(1) to O(n), which is a common cause for TLE

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13 months ago, hide # |
 
Vote: I like it +20 Vote: I do not like it

Damn. You really made bro reflect on his actions and repent.

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13 months ago, hide # |
 
Vote: I like it +3 Vote: I do not like it

Lol bro cheated and went into ICPC

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13 months ago, hide # |
 
Vote: I like it 0 Vote: I do not like it

It never even began for him.

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13 months ago, hide # |
 
Vote: I like it +6 Vote: I do not like it

My train of thoughts at the end of the blog:

"Who are NEU.Newbies? I swear I had been monitoring the scoreboard of VN site in and out on contest day and this team never scored any remark in my head?"

"Oh... 4 solved, struggling hard on 2 trivial ones."

...Truly a red performance.

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13 months ago, hide # |
 
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The fact that AI can do this well not only on Codeforces but also in USACO and AtCoder is very concerning

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Just a frustrated penguin here from Heard Island Spent months solving dp problems in the freezing cold , dreaming of becoming a Grandmaster Now people just use AI to get there with zero effort And as if that wasn’t enough, America’s throwing tariffs on our poor island too— for what, frozen wind? With AI taking over and ice getting taxed, even trying feels pointless now

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