Hello CodeForces!

I would like to invite you to participate in a testing round for a training contest prepared for an Olympiad camp.

The contest was created to replicate the algorithmic skills and approximate difficulty of last year's Camp 1 end-of-camp contest. The problems have been recreated, with some modifications, especially to the constraints and story.

Since I prepared the contest by myself, I would really appreciate having some testers before it is used in the actual camp.

The testing round will start on September 18, 2026 at 12:00 (UTC+7) and will remain open for three days.

Everyone is welcome to participate!

I would especially appreciate feedback regarding:

• unclear or confusing statements
• weak tests
• unintended solutions
• approximate difficulty of each problem

The contest is intended for students attending their first Olympiad training camp, so the goal here is to get feedback.

If you find anything strange or have any suggestions, please leave a comment or send me your feedback.

If you are a student you may attempt these problems for practice.

Please note that only C++ submissions are allowed. The contest also uses strict output checking, so leading or trailing whitespace is not allowed in the output.