Welcome to the first ever UACC — Unionville Algorithmic Coding Challenge, a competitive programming contest series hosted by Unionville High School!

This contest consists of 6 problems listed in order of approximately increasing difficulty, ranging from CCC Junior to CCC Senior level. Each problem is worth 100 points.

The problem authors are RickeyZ, DavisLiu, ayay9, and 7kxb.

Thanks to Josh, Joelfu, cccsolver, Snowfall, davidhu2006, Marshmellon, yunz_qiao, and jgcodes2020_alt for testing and feedback on the problems!

Special shout-out to Riolku and Kirito for helping us organize the contest!

The contest will be unrated and will run from Friday, January 5th to Monday, January 8th, inclusive of both days.

You will have 3 hours to complete the contest. After the contest window begins, you may begin at any time. Once you enter the contest, your personal timer will start counting down, and you will be able to submit until 3 hours from when you started, or until the hard deadline (00:00:00 EDT of January 9th), whichever comes first.

Prizes will also be available for the contest! These include:

• $15 gift card for placing first overall
• $15 gift card for winning a raffle (2 winners)
• $10 gift card for placing first in UHS

You will be automatically entered into the raffle upon obtaining a non-zero score. Prizes will be DM'ed to the Discord account associated with the winning DMOJ handle, and each account can only win once.

Gift card selections are: Amazon, Apple, Google Play, and Steam.

Here are the contest parameters:

• Some problems offer partial marks in the form of subtasks.
• There is no submission limit.
• There is no incorrect solution penalty.
• Checker: unless otherwise specified, standard.
• Ties in score will be broken by the last submission time that increased your score.
• All problems are guaranteed to be solvable in C++.