What you are actually walking into, and what the rules allow.
Day 1 - the theoretical round
Paper-style problems worked on a laptop, with answers typed up and submitted as PDF. The questions are mathematical and algorithmic: derive a result, trace an algorithm, justify why a method applies. This is closer to a maths olympiad paper than to a Kaggle notebook, and it is the round that most surprises students who prepared only by training models.
Day 2 - the practice session
A supervised run at the exact machine and environment used for the practical round, so nobody loses contest time to a missing package or an unfamiliar editor.
Day 3 - the practical round
Code-based model building, Python only. The organisers supply one laptop per competitor with the environment configured and datasets already loaded, and internet access is restricted.
The ten-domain syllabus
Data preparation; supervised learning with regression, classification and regularisation; unsupervised learning with clustering and dimensionality reduction; reinforcement learning; AI search; logical reasoning; ML model evaluation; constraint satisfaction problems; kernel methods and SVM; and recommender systems. Note how much of that is pre-deep-learning material.
Ranking
Final ranking is individual, with medals awarded on individual performance. An informal country ranking is published alongside, as at other olympiads.