About the Central-European Olympiad in Informatics (CEOI)

The Central-European Olympiad in Informatics (CEOI) is a prestigious programming competition for high school students across Central Europe. Around 40 participants from 10 countries gather to solve complex algorithmic problems. Each country sends its top four students, who are selected through national olympiads held in the months leading up to the CEOI.

History and Participants

Established in 1994, the CEOI regularly invites delegations from Croatia, Czech Republic, Germany, Hungary, Poland, Romania, Slovakia, and Slovenia. Other countries may also be invited as guests. In 2025, the competition featured 8 regular and 5 invited countries.

Format and Connection to IOI

The CEOI's competition format mirrors that of the International Olympiad in Informatics (IOI), the annual world programming championship for secondary school students. Over two contest days, participants face a 5-hour exam where they write programs to solve challenging algorithmic problems. These programs are then scored based on their efficiency and correctness. For many CEOI countries, the event serves as a valuable practice ground for their IOI teams.