Hello, in this post I will describe what I believe to be a very severe and elaborate case of cheating that took place on the just recently finished ICPC 2025 Online Winter Challenge powered by Huawei contest.

For context, the challenge is a 16 day contest with a large prize pool where contestants solve one optimization problem and aim for a score as high as possible. On the last day of the contest (precisely the last 6 hours), I was very surprised to find that multiple unrated accounts or accounts with minimal activity and background were able to unexpectedly replace the previous top scorers, earning them the places worthy of the first (8000 eur) or second (3000 eur) prize.

I was interested to learn who these brilliant competitors were since their profile gave me no information so I tried to google their usernames, mostly ending up with no results but one in particular led me to this very interesting blog on Codeforces: