Contest format

The format decides how a contest is scored and ranked. Eolymp has two: IOI, where problems carry points and partial solutions count, and ICPC, where a problem is either solved or not and time is penalised. You pick the format when you create the contest.

The format is locked once the contest has its first submission, and locked again — permanently — once the contest is finalized. Until then it can be changed on Settings → General.

IOI

Used by the International Olympiad in Informatics and the school-level olympiads modelled on it.

A problem's score is the highest score among all of the participant's submissions to it, partial credit included — a problem divided into subtasks or test groups gives points for the parts that pass. The total is the sum of the per-problem scores, and participants are ranked by that total. There is no penalty.

This format rewards getting as much of a problem right as possible, which is what makes it suited to long problems with graded difficulty inside them.

Fig 1. An IOI scoreboard: a score per problem, and the sum.

ICPC

Used by the International Collegiate Programming Contest and the university-level contests modelled on it.

Each solved problem contributes one point, so the total is the number of problems solved. Partial solutions count for nothing. Ranking is by the number of problems solved, and participants on the same number are separated by penalty time, which accumulates as follows:

• A solved problem adds the number of minutes from the start of that participant's participation to the accepted submission.

• Each unsuccessful attempt before the accepted one adds a fixed penalty — 20 minutes by default, changed with Attempt penalty on Settings → Scoreboard.

• A problem that is never solved adds no penalty at all, however many attempts were made.

• Submissions made after the problem was solved are not counted as attempts.

• Submissions that failed to compile are not counted as attempts.

The lower penalty ranks higher. The Attempt penalty setting exists only for ICPC contests, and only ICPC contests show a penalty axis on the participant's score chart.

Fig 2. An ICPC scoreboard: solved problems, time to solve, and failed attempts.

What the format does not decide

Two scoring options belong to each contest problem rather than to the format, and apply in both:

• Score using best result per testset — the problem's score is the sum of the best score achieved in each testset across all of the participant's submissions, instead of the score of a single submission.

• Attempt limit — a cap on how many times one participant may submit that problem.

The maximum score of a problem comes from the problem in the library and is shown, not edited, inside the contest.

Which submissions count towards a rank, and how ties are broken, is described in Contest scoreboard. What a submission's status and verdict mean is in Statuses and verdicts.