Hello, Codeforces.

I've participated a few rounds and noticed that there are too many cheaters. Now the cheater detection is community-driven and only a few of cheaters are being detected.

Idea

I’m proposing Codeforces Anti‑Cheat (CFAC) – an automated flagging system that works after each contest and automatically detects cheaters using:

— NLP-model based submission (and maybe replacement) checking

— Timings-based detection: if gray solves div.2 e in 3 mins, its suspicious

all of these metrics are combined into suspicion score matrix where score[u][p] is value normalized [-1, 1] where

— -1 — if participant $$$u$$$ 100% not cheating at problem $$$p$$$;

— 1 — if participant $$$u$$$ 100% cheating at problem $$$p$$$;

Need help

I need help in

— collecting labelled data for cheaters and not cheaters

— final testing of anti-cheat system

Updates

• Created cfac repo on github
• Updated post text without AI addressing hate comments about AI-slop and pilliamw blog post