Those small tasks show you a bit what the tasks of the SOI might be like. The official first round starts on September 15, 2025. If you enter your email address below we will notify you once the round starts.

Now you can solve the problems and check your solutions. Each task consists of several questions (like for example this problem with questions SUM, LAB, SCL, ALG etc.). Some problems have an interactive visualization to help you solve them. And for some you can try to write a program to solve it.

If you have any questions regarding the tasks or the competition as a whole you can ask us anytime: info@soi.ch

Have fun!

SOI is a programming competition for young people under 20 years of age. In different rounds you can solve tricky tasks and learn efficient programming. Participate - maybe you will travel to the International Olympiad in Informatics in Uzbekistan in summer 2026!