if you dont know OI Style, basically, the problems have a specific number of points (usually 100 points) which you gain after solving the problem.

Each problem is divided into a bunch of sub-problems each having a specific score so you can solve a sub-problem and gain a partial score (30 points out of the 100 available points for example).

Sub-problems usually differ than the full problem by having lowered constraints.

The sub-problems might have simpler observations or easier solution (brute force solution for example).

There is no penalty for wrong submissions in OI style, the only factor determining the standing is the number of points a contestant has.

If you have any question about OI style feel free to ask any of the authors either right now or through a clarification during the contest