IOI 2018 took place in Japan in September, 2018. More info is available on the official website.
Just happened IOI 2018 in Japan
The idea of initiating international olympiads in informatics for school students was proposed to the 24th General Conference of the United Nations Educational, Scientific and Cultural Organization (UNESCO) in Paris by the Bulgarian delegate Professor Blagovest Sendov in October 1987. This plan was included into the Fifth Main Program of UNESCO for the biennium 1988-1989 (Section 05 215).
In May 1989, UNESCO initiated and sponsored the first International Olympiad in Informatics (IOI). (Quoted from the IOI'89 and IOI'92 Report). The first IOI was held in Bulgaria in 1989.
The IOI is organized annually in and by one of the participating countries. Each participating country typically sends a delegation of four contestants and two accompanying adults. Students compete individually and try to maximize their score by solving a set of informatics problems during two competition days. Cultural and recreational events are organized on the remaining days.
The competition tasks are of algorithmic nature; however, the contestants have to show such basic IT skills as problem analysis, design of algorithms and data structures, programming and testing. The winners of the IOI belong to the best young computer scientists in the world.
Locations of past and future IOI's include:
Please note that each link contains problems, test cases and/or solutions.
The IOI is one of five international science olympiads. The primary goal of the IOI is to stimulate interest in informatics (computing science) and information technology. Another important goal is to bring together exceptionally talented pupils from various countries and to have them share scientific and cultural experiences.