Title: Cheating Report: Account NGUYENVUHOANG in Codeforces Round 1125 (Div. 3)↵
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Hello everyone,↵
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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.)↵
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I am writing this blog to report account [user:NGUYENVUHOANG,2026-10-08] for cheating in Codeforces Round 1125 (Div. 3). ↵
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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, [user:NGUYENVUHOANG,2026-10-08] 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.↵
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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.↵
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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.↵
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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.↵
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[user:MikeMirzayanov,2026-10-08] [user:geranazavr555,2026-10-08] read this blog please.
↵
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 [user:NGUYENVUHOANG,2026-10-08] 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, [user:NGUYENVUHOANG,2026-10-08] 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.↵
↵
[user:MikeMirzayanov,2026-10-08] [user:geranazavr555,2026-10-08] read this blog please.
