Swiss Olympiad in Informatics

First Round

More about the First Round

The First Round is a 35-minute online quiz with multiple-choice computer science questions. Basic programming knowledge is helpful, but not required to advance. The First Round is ideal for solving in class; you are invited to ask your teacher about it. In case you do not have the opportunity to participate at your school there will be an option to take part individually.

Second Round

Pick your favourite programming language and solve the tasks of the Second Round online.

Tasks for the contest 2027

The Second Round is conducted online. Everyone who satisfies the conditions of participations can participate. There are two categories: junior and regular. If you can participate this year and the following two more years, you are eligible for the junior round. The five tasks are chosen to promote creativity and good ideas – prior knowledge in programming and algorithms is useful, but not required.

Workshops

The graph lecture during the workshops.

The workshops teach you everything you need to know to solve the tasks of the Second Round. You’ll learn about C++ and algorithmic problem solving. The workshops can be attended free of charge. No matter how much background knowledge you have, you will certainly benefit.

The dates at which these workshops will take place will be announced soon.

Sarnen Camp

Group picture in 2026 in Sarnen

The Sarnen camp is a week-long training camp for top 16 participants from the regular round, the top 8 participants of the junior round and some guest countries. There are lectures, practice tasks and training contests, but there is also ample time to meet the other participants and have lots of fun.

Finals

Finals 2026 at EPFL

All participants of the Second Round which qualify for the SOI-camp also qualify for the Finals. Participation at the camp is not mandatory for participation in the Finals.

The Finals consists of two parts:

• FP (800pts, practical): Two practical exams of 5 hours each.
• FH (200pts, “homework”): solve some full-feedback training tasks starting from December 1st

Team Selection

Solution presentation at Team Selection 2026

The top finalists are invited to the Team Selection in Bern. Additionally, wild cards can be given, usually there are 12 participants in total. At the Team-Selection, the delegations for the IOI and other international contests and training camps are selected.

During the Team Selection there are four practical programming contests that are held on two times two days in Bern. We recommend to use the C++ programming language, though Python is also allowed; these two are the only languages allowed at the Team-Selection and at IOI.

WEOI

The Swiss delegation at WEOI 2025 in Volterra

WEOI

The WEOI, the Western-European Olympiad in Informatics, is the youngest and shortest international Olympiad where Switzerland participates. It takes place on a weekend, and everyone brings their own laptop to write the contest on. SOI sends a delegation of up to eight contestants and two leaders. In 2028, WEOI will be hosted in Switzerland for the first time.

CEOI

The Swiss delegation at CEOI 2026 in Ljubljana

CEOI

The CEOI, the Central European Olympiad in informatics, is similar in style to the IOI. While smaller in scale, getting a medal is usually more difficult than at IOI.

IOI

Two bronze medals for Switzerland at IOI 2019 in Baku

IOI 2027

Over 80 nations send their 4 best students to compete in the International Olympiad in Informatics (IOI). The IOI is the most important, but not the only international event where the best participants of the SOI can meet, exchange and compete with other teenagers.