International Olympiad in Informatics

The contest consists of two days of solving six complicated algorithmic tasks by writing computer programs in C++.

[1][2] All task materials are published on each year's contest website soon after the competition ends.

Each student works on their own to solve the problems with no outside help, specifically no communication with other contestants, books, web access, etc.

[3] Usually to solve a task the contestant has to write a computer program (in C++) and submit it before the five-hour competition time ends.

Another type of problem has the inputs publicly available, for these, the contestants have to submit an output file instead of a program, and it is up to them whether they obtain the output files by writing a program (possibly exploiting special characteristics of the input), or by hand, or by a combination of these means.

In IOI 2012 the top 3 nations ranked by aggregate score (Russia, China and USA) were subsequently awarded during the closing ceremony.

[6] President of the IOI (2011-2014), Richard Forster, says the competition has difficulty attracting women and that in spite of trying to solve it, "none of us have hit on quite what the problem is, let alone the solution.

[4]:11 Due to visa issues, the full USA team was unable to attend, although one contestant Zhezheng Luo[8] was able to attend by traveling with the Chinese team[9] and winning gold medal and 3rd place in standings.

The IOI 2022, hosted by Indonesia, was held as a hybrid event, with around 25% of the contestants participating online.