belalahmed_'s blog

a new round with a new cheater
By belalahmed_, history, 12 months ago, In English

This newbie sa07885 AK that div 4 and reached specialist!

And he used a completely different code template at the submission of the last problem here 315380280 compared to the rest like this 315433305

And it looks like he used an AI code generator

when I used AI code detector to check, it said: Highly Likely AI-Generated Probability: ~85–95% AI-generated, possibly by ChatGPT or a similar model trained on competitive programming problems.

  • Vote: I like it
  • +16
  • Vote: I do not like it

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12 months ago, hide # |
 
Vote: I like it +12 Vote: I do not like it

He is obviously using ai , look at comments in the solution to the last problem of decent div 4 contest

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

    i am just a newbie and not supporting anyone here, and i agree that comments can make the code suspicious but how can we come to conclusion that a person is cheating if he uses different templates? just curious, pls dont downvote

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12 months ago, hide # |
 
Vote: I like it -99 Vote: I do not like it

Based on what you have just said, you obviously haven't done your research. I don't need to prove anything. You would have known better if you had looked at my profile and known how to evaluate it.

And the reason, I "didn't" use my template for the last question is "I started solving from the last question, at which point since I was in another system, my templates were still downloading. But after that, it was normal.

Next time before you accuse someone, know better than to just accuse them.

Fun Fact: You solved a total of approximately 400 problems long ago while I solved over 200 problems within just 2 months. And most of the questions that you have recently span from 800-1400 while mine span from 800-2000. :)

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    12 months ago, hide # ^ |
    ← Rev. 2  
    Vote: I like it -80 Vote: I do not like it

    The code looks too clean, efficient, and performance-aware to be fully AI-generated without strong human guidance. It feels more like the work of a competitive programmer, possibly with some AI help for structure or boilerplate — but the key logic and optimizations seem human-crafted. ~ From AI Code Checker LLM

    Also, 4 problems that you have solved in the last month, compared to mine 108 problems last month and the month before that spanning from 800-2100 or above...

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

    Your first wrong submission for H was made using your template 315378795 (similar to the ones used in your later submissions). When that failed, you completely removed the template and submitted a different solution (probably AI-generated) 315380280. Later, you switched back to using your original template.

    Also, the time gap between both submissions of H is less than a minute.

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      12 months ago, hide # ^ |
      ← Rev. 2  
      Vote: I like it -31 Vote: I do not like it

      Yes, and do me a favor and read the "void solve()" function. That was the code for a different question which I did in the past (more specifically, this: https://mirror.codeforces.com/problemset/problem/1948/C ) because I submit by file. Also, my template if you see is much more optimized compared to the last one.

      And, if it was really a wrong submission, then it would have shown "+1" in my standings, which it didn't

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        12 months ago, hide # ^ |
        ← Rev. 2  
        Vote: I like it 0 Vote: I do not like it

        Okay, fine, so you’re saying you had access to your previous code files with the template, but earlier, you mentioned you were on a different system—so which one is it?

        Also… who’s gonna tell him that if we submit the correct solution within 10 minutes of a wrong one, we don’t get the ‘+1’ in our standings?

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

        And, if it was really a wrong submission, then it would have shown "+1" in my standings, which it didn't

        it didn't because only contests with CPC style will count the WA on test 1 as a wrong answer

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    12 months ago, hide # ^ |
     
    Vote: I like it +8 Vote: I do not like it
    Bro is playing in third person irl.
    Totally, agreed on his skill, after seeing how much time he invested to write these extremely sane comments in his copied precode.

    And even after all this, if you still insist that the solution was by your own skill, would you mind explaining how this new template appeared out of nowhere mid contest? Or you forgot the place from where you copied this new template of yours from, by another mere (fateful) coincidence?

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

    Your aggression to the blog author indicates that your solutions are all AI-generated. Ngl ts pmo

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12 months ago, hide # |
← Rev. 2  
Vote: I like it -50 Vote: I do not like it

I know sa07885 as a fellow student at Habib University, and we are both currently enrolled in the "Competitive Programming" course. While I cannot comment on the specifics of any ongoing investigation, I would like to share my personal observations from working alongside him in this course.

In our lab sessions, we work on university lab PCs that have no access to the internet or our mobile phones. Given this restricted environment, the use of AI tools or any external assistance is simply not possible. Despite these limitations, sa07885 consistently performs exceptionally well and is often among the top 3 performers in our lab. He regularly solves problems rated between 1000 and 1800 with impressive speed and accuracy.

I want to make it clear that I am not involved in, nor am I supporting, any form of academic misconduct. My intention is only to provide a truthful account of what I’ve seen in our shared academic setting.

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

    Just because someone can code does not mean they can't cheat; there are plenty of instances where highly skilled people have resorted to cheating

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12 months ago, hide # |
← Rev. 2  
Vote: I like it -12 Vote: I do not like it

Alright, seems there are some questions floating around about whether I used AI in the contest. Let me lay out how things went down, and hopefully, that clears things up. If you still have specific doubts after reading this, feel free to point out a concrete reason.

So, about my code – if you look at my profile, you'll see I pretty much always use my own template. It's visible in my other contest submissions and loads of practice problems. You might even spot my old template style in past attempts, or that time I accidentally submitted the wrong file for "H" – it used to be way longer. Right before this contest, I actually streamlined it: put the core stuff in the main file and moved things like number theory code (think 'sieve') into another file, just ready to copy-paste if needed. Made things quicker.

Now, the contest itself was a bit unusual for me. My own laptop was being glitchy, so I jumped onto my brother's computer. This meant I had to quickly send my templates over to his machine. While those files were downloading, I didn't want to waste time, so I just started hammering out the code for problem "H" directly.

Speaking of "H", that one took a couple of tries. My first attempt at the pre-computation part hit some weird indexing error. Honestly, I stared at it for a bit but couldn't pin down the bug quickly, and there were quite a few moving parts to keep track of (the 'J' variable, divisors, the 'current_k', 'next_j', managing positions, etc.). It felt messy. So, I decided the fastest way forward was just to restart "H" from scratch with a cleaner structure in mind. Wrote it again, submitted, and thankfully, that version passed.

As for why I tackled the problems in the order I did (H, G, F first): the rating cap was 1400, and problems around that level usually feel pretty approachable to me. My thinking was just to spend my main focus on the higher-point problems first, while I was fresh. After H, G, and F, I went back and did the first five. "E" stood out as interesting (that contribution + bitmasking idea), while the others from A to D were more straightforward conceptually, though naturally, the coding still took a bit of time to get right.

So, that's the rundown. I really hope this gives a clearer picture of my process during the contest.

P.S. belalahmed_, given that this topic has come up, could you share which AI code checker was used? Since I'm confident my submission was my own effort, knowing the specific tool would help me understand what aspects of the code might have drawn attention or how the automated analysis works in practice.

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    12 months ago, hide # ^ |
     
    Vote: I like it +25 Vote: I do not like it

    Sure, downloading a 2 KB file requires a lot of time.

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      12 months ago, hide # ^ |
      ← Rev. 2  
      Vote: I like it -8 Vote: I do not like it

      The file was sent via WhatsApp and was definitely over half an MB. Add WhatsApp's own loading delay and my slow network at the moment, it became impractical. Hence, loading problem H directly and starting it on m3.codeforces.com was the faster route.

      Although your comment isn't the type of concrete feedback that I was expecting, I'm responding specifically because a comment from a 2700+ rated user carries significant weight – it implies a level of insight and judgment that warrants careful consideration.

      Hope this clarifies the situation.

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

        The submission size limit on Codeforces is 64 KB, so your file cannot be over half a MB...

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

          Not the "code file". My "zip file" which consisted of all the essential template code and the files to have fast execution optimized for my use.

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

            Can you send them here?

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

              Here? How? It's a zip file.

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

                You can use Google Drive, Dropbox or anything similar.

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

                  he was just checking whether ai could solve div4 problems or not thats why started from H . this is the confidence which is needed to succeed

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                  12 months ago, hide # ^ |
                  ← Rev. 2  
                  Vote: I like it 0 Vote: I do not like it

                  Sorry, I missed your message earlier — it was almost midnight, so I went to sleep.

                  Regarding your suggestion, that's a great idea! However, I'd prefer not to share it here, as I find feedback from others to be quite subjective and inaccurate.

                  If you're comfortable sharing it, could you send me your Discord handle in CF DMs? I'd be happy to forward it to you privately there.

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

                  Your submission has already been skipped, so we don't need further evidence.

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    12 months ago, hide # ^ |
    ← Rev. 2  
    Vote: I like it +3 Vote: I do not like it 
    if (a[i] >= 2 && a[i] < MAX_VAL) { 
     if (pos[a[i]].empty()) { 
         distinct_a_values.push_back(a[i]);
     }
     pos[a[i]].push_back(i);
}

    No sane person would do this. Seems like you didn't even read the constraints and got accepted. 315380280

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12 months ago, hide # |
← Rev. 2  
Vote: I like it +8 Vote: I do not like it

me reading every "cheater" blog comments with a bucket of popcorn.

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

i have sufficient proof to prove he cheated its clear if you compare his submissions

315380280 and 315378795 there is not even similarity of 1% and he quickly got correct ans in 1 min in which changed the template and submitted it its damn fast i take that time to copy test cases and paste them in my compiler its crazy!

i hope strict action is taken against him

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12 months ago, hide # |
← Rev. 2  
Vote: I like it 0 Vote: I do not like it

Bro's whole college has arrived in the cmnt section ;;)

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

hence proved to be a cheater his 315380280 has been skipped so belalahmed_ was right .

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