Title: Cheating Report: Account NGUYENVUHOANG in Codeforces Round 1125 (Div. 3)
Hello everyone,
I am a student from Kon Tum High School for the Gifted in Vietnam and a member of the Vietnam Olympiad in Informatics (VOI) training team. (Note: Since my English is not very good, this blog post was translated and polished with the help of AI.)
I am writing this blog to report account NGUYENVUHOANG for cheating in Codeforces Round 1125 (Div. 3).
Before going into details, I would like to clarify that this post is not driven by personal envy. During internal training contests organized by our school teachers, NGUYENVUHOANG repeatedly used ChatGPT to solve problems. He routinely solved 2500+ rated problems in under 5 minutes with complex code over 100 lines long, despite being only 16 years old. In short, he relies heavily on AI to generate solutions for almost every problem.
Looking closely at his submission timeline in the recent Div. 3 contest: - He solved the first 3 problems (A, B, C) in just 5 to 7 minutes each. - After getting AC on problem E after 20 minutes, he miraculously took only 6 minutes to get AC on problem D, followed immediately by another 6 minutes to get AC on problem F. (It is completely unreasonable to read, fully comprehend, and code a solution for problem F in such a short window). - Although his initial solution for problem H was hacked due to a hash collision, he managed to submit another AC solution 40 minutes later on problem H — a problem that had roughly only 200 ACs on the unofficial leaderboard.
Additional Evidence: - AtCoder Profile: https://atcoder.jp/users/nvhoang I can confidently assert that he cheats on AtCoder as well. Inspecting his submission history reveals structural patterns, variable naming, and coding styles characteristic of AI-generated code with minor manual tweaks.
As someone who values integrity, I cannot stand by and let the reputation of our school's Vietnam Olympiad team be tarnished by dishonest behavior. I hope the Codeforces admins review this submission history and take appropriate action against this account.
MikeMirzayanov geranazavr555 read this blog please.
To be honest, sometimes I feel very very embarrassed when Vietnameses cheat. In fact, the number of cheaters in Vietnam is around top 2-3 in the world. Hopefully people like mambo won't say that our country is trash just because of a dumbass who cheated.
To be honest, the most cheaters come from India [no hate, just a fact...]
I was about to say where is india in cheating.
But I do not cheat I am happily 860 rated coder, but I still wonder do people who are 2800+ rated do they solve while reading A question of Div 3 and submit the moment they finish reading?
India is literally #1 in terms of cheating on codeforces [check out my blog if you don't believe], +ur question about how high rated ppl can destroy div 2/3, is simply that they practiced a lot, so there typing improved, thinking improved, and knowledge improved, its nothing like magic [though it sounds like magic to u]!
I already agreed bro be it scammers or leetcode AI submissions, or CF contests, among cheaters you will see many are indians.
Because I also see these kind of posts on my linkedin or youtube.
But not all are like that majority are really good coders at CF(though we don't have many LGMs only 1 LGM is from india), some cheap mindset people are like that.
Yeah, sometime I often ask myself "how did tourist spent 2 seconds thinking this B div1" while I'm struggling with C div2 lol
While I am just able to solve Div 2 A that also luck based, and in B and C of Div 3 I do implementation errors. You are better than me bro, so chill.
Its a matter of time, and timed practice.
You are literally from India, the only thing I see you is just spreading hate. There are other countries that cheat too, But... It seems that you target only the Indian cheaters (your blog is only about them) Out of millions of users of Codeforces, you target a specific group of cheaters which isnt good. I am not saying that cheating is a good thing but pls dont be selective.
Are you a brown sepoy?
I think its not hate and its a fact that Indian cheaters are the biggest group of cheaters on codeforces, not all, because also many legendry figures are also from India [eg. Dominator069, aryanc403, etc]. So its not hate, just a fact, +when i mentioned in my blog about cheaters, it was just a coincidence that literally all of them from India (5) and only Indian cheaters were in the top 100-200. Indian CPers need to understand this that cheating leads them to nowhere. You can also see past contest's standings, you could see that most of them are Indian cheaters. I've no hate against India but this is also not acceptable!
The population is proportional to the number of cheaters, and the only reason India has so many cheaters is its large population.
If CP were introduced to Indian students in, say, 5th or 6th grade and taught as a subject in schools, I’m sure that, despite the huge population, we wouldn’t have nearly as many cheaters.
So, saying “Indian CPers need to understand” doesn’t make sense. You can check the statistics, but in every country where CP isn’t encouraged or taught as a subject, the percentage of people cheating increases drastically. Targeting only Indian JS seems like racism, because people in other countries where cp isnt promoted do it too.
your first 2 points are entirely true, that if cp is introduced to every student in India, then India could produce many LGMs, just like other countries, +yes, India has a large userbase here on codeforces. And yes, cheating is not only found in India, it's also found in other countries, but, in my blog literally 100% of the past round competitors (cheaters) were from India, and this is surely not good, instead of portraying this as racism, view this from a perspective of true competitors who don't cheat, like you and me. Many of the users also have cheated and created a new account and stopped cheating, that's a second chance to them, a new start! And, also me being a citizen of India, I surely don't hate my country, nobody does, but the people who cheat here, i don't like them at all, neither do the admins. CP is a sport, a mind game, if you cheat in every game, then what's the fun of playing it?! Instead of hiding yourself [cheaters] from the reality, face it, fix ur skill issue, then come back, then produce some real output!
i wasnt talking about your blog, but literally your every 1 in 2 comment on this id is talking about indians!, this shouldnt be done
i dont think this should even be a topic to talk about, u can check for any country with less awareness about cp, and majority of their population will be cheater
so we cant js target every country right? so the best option is to 1)spread awareness, 2)if u cant spread awareness then dont spread hate too.
ik i shouldn't always target India, but its a primary fault of the education system (rote leads to nowhere) and the mentality...
yea ig u r right about that...
btw our gov is trying its best to fix that, new grade 9 books (grade 10 11 12 books will be launched in further years) focus on critical thinking and maths question are framed like olympiads too
maybe things will change in future
i think they should introduce cp as early to class 4/5, where experience from class 4 — 7, will be of 3 years and they can do a lot in 3 years, also their primary focus should be only on mathematics + AI (not using it) + science (domain specific) + programming (CP oriented), i dont think that what they're teaching now will have affect in the next 5-6years
Imagine trying to earn contribution while hating your own country.
Holy sepoy mindset
cry on ur own contrib...
Cry on your rating.
ur the one larping...!!! lmao!!
Bro they should just introduce CP and only test CP in exams that's it nothing more needed, either they don't want to or they don't want to do it.
who will grade the exams? those teachers who teach print() input() of python in 12th grade??
its fucked up bro js accept it and move on, i dont even know why people talk about cheating nowadays depsite knowing THERE IS NO ESCAPE
No need use codeforces.
Can you explain China?I think your viewpoint is not necessarily correct. I think about India's cheaters many,population isn`t only reason.
i never said only 1 reason, i mentioned 2 reasons please read them both
I think your comments were completely unnecessary over here. The person in question had nothing to do with India so you bringing India up out of nowhere does suggest a personal vendetta.
Yeah total waste of time
"if u cant beat them , then join them" marvyzy
(them->racists)
marvyzy is just a brown sepoy.
Imagine earning contribution while hating your own country
i think neglecting the reality is within you.... I can do absolutely nothing about it, sorry!
So you agree you have sepoy mindset. Congrats! Your just Indian version of mambo
how many times you'll repeat the same phrase with different ways of saying it, you're alr so roasted, so idc what you say...
agreed bro
mambo quit...
he's back
last visit 3 months ago
mambo
mambo
Honestly, India ranks first with 530 flagged cheaters, and... THAT'S NOT ALL! There are even more cheaters who didn't list their nationality, so I guess there could be MORE.
Nice Vietnamese cheater
real
This 393609596 so suspicious
absolute cinema
Hi Ahanab,
I am surprised to see this blog, but I appreciate the opportunity to clarify a few points regarding my contest performance:
Time gaps between D, E, and F: In Div. 3 contests, problem statements are straightforward. While implementation for E was underway, I had already read and thought through the ideas for D and F. A 6-minute window for D and F represents coding time, not total thinking time.
Problem H (Hash Collision & 40m Debugging): My original solution for H failed due to a hash collision (which got hacked). It took me nearly 40 minutes to analyze the collision, adjust my hashing parameters, and resubmit an AC solution. This manual trial-and-error debugging process clearly demonstrates genuine problem-solving rather than copying or prompt-generating.
Coding Style & Templates: My code consistently utilizes standard competitive programming practices typical for VOI training: global static arrays for cache performance, compact variable names (u, v, kq), and customized fast I/O snippets. This template is identical across my Codeforces and AtCoder profiles.
I welcome MikeMirzayanov or any Codeforces coordinator to inspect my submission code diffs and history. I am always open to healthy competition and constructive discussions. Please see my blog here: https://codeforces.me/blog/NGUYENVUHOANG
that's suck blog
Hi
yo your name???
nguoi viet bay ma khong can canh
Vietnamese fly without wings 🐧 🐧 🐧
Vietnamese fly without wings 🐧 🐧 🐧
.
Vietnamese fly without wings 🐧 🐧 🐧
người việt bay mà không cần cánh 🐧 🐧 🐧
nguoi viet bay ma khong can canh
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Vietnamese fly without wings
Was it really necessary to write Vietnamese in the title? Why highlighting a specific country?
Agree, I think the title is unnecessary
Bro is going to write "The great wall of Vietnam".(It's just a joke)
Vietnamese fly without wings
Vietnamese fly without wings
Auto comment: topic has been updated by Ahanab (previous revision, new revision, compare).
Instead of wasting time on this cheater, you should focus on yourself. Yes, they are definitely using AI, but you must strive to be better than them. In the future, AI might take your job if you are not more skilled than the people who just rely on it. So, it's much better to focus on your own growth. If you become better than these AI cheaters now, you will be the one succeeding in real life, while they will completely fail without their AI tools.