We encourage you to work in teams of three, but you may compete individually or in a team of two.
Each team will register in one of the following divisions.
Division 1
This is for more experienced problem solvers. A spectrum of difficulties will appear here from very easy to quite challenging, some of the problems will require experience with algorithms and data structures. The only requirement is that all members must be students.
Division 2
This is the more introductory division, the average difficulty will be lower than Division 1 and fewer problems will rely on knowledge of algorithms or data structures (though there will be some). Your team may compete in this division if every team member is a student and none have won prize money at a previous UAPC or ACPC.
Exception: Teams consisting of only grade school students may register in this division even if they have won a prize in a previous UAPC or ACPC.
High Shool Division
Restricted to teams consisting entirely of grade school students. Most problems will be of an elementary nature, though there will still be some challenges.
Open Division
This is the unofficial division. Anyone may participate in this division, even if they are not a student. No prizes. You don't even have to fill out the registration form unless you intend to compete on site, you can just join the contest when the url goes live.
For questions about eligibility, email the contest organizer (Zac Friggstad).
Ranking
A problem is considered solved if one of your team's submissions for that problem receives a judgement of
Accepted from the judging platform. Participants that are not familiar with the judging platform
are strongly encouraged to try a few practice problems themselves to understand how judgements are given, see the "Other Information" box for details.
There is no partial credit, any judgement apart from Accepted means the problem is not yet solved by your team.
You may resubmit as many times as you would like.
The team that solves the most problems wins. Ties are broken by the team with the least penalty points.
Penalties points are calculated as follows. For each problem that is accepted, you receive M + 20*W penalty points
where M is the number of minutes from the start of the contest before your first Accepted verdict for this problem
and W is the number of incorrect submissions for this problem before your first Accepted verdict.
See the 2023 Division 2 scoreboard for an example of how ranking is done.
More details about scoring can be found here.
Scoreboard Freezing
The scoreboard typically "freezes" when there is 1 hour remaining in the contest. You are able to see the verdicts for your own submissions but the scoreboard will not update
apart from showing a submission count from other teams during the final hour (i.e. you will not know if it was accepted or not).
The scoreboard will be unfrozen after the contest to reveal the final rankings. The contest administrators reserve the right
to change the time of the scoreboard freeze, but this is rare.