A mathematician reflecting on the International Olympiad in Informatics

In July 2013, students from 80–90 countries will descend upon Australia to take part in the International Olympiad in Informatics (IOI). On the surface the IOI is a computer programming competition, but in fact it involves a great deal of both mathematical technique and mathematical creativity. In this short article we introduce the readers to the IOI and the mathematics within. 1 Introducing the IOI The International Olympiad in Informatics (IOI) is one of the five broad-brush Science Olympiads for high school students, which also cover Biology, Chemistry, Physics, and of course Mathematics. Founded in 1989 under the auspices of UNESCO, the IOI is one of the youngest Science Olympiads, but it has grown quickly to now include over 80 countries, making it the second-largest (behind only Mathematics). Despite “informatics” being roughly synonymous with computer science, the IOI has always had strong associations with mathematicians. Locally, the Australian team is trained by the Australian Mathematics Trust, and all of Australia’s team leaders over the past decade have been trained mathematicians.1 Internationally, the first IOI was organised by Petar Kenderov, a highly-respected Bulgarian mathematician, and it is common to find fellow mathematicians amongst the myriad of team leaders and deputies. It was recently announced that Australia will host IOI 2013, with the event to be held at The University of Queensland in partnership with the Australian Mathematics Trust. This is a great honour for both the mathematics and computer science communities in Australia, and readers will doubtless hear more about the event as it draws nearer. In the meantime, this short article aims to (i) introduce the IOI to readers with whom it is unfamiliar, and (ii) illustrate the mathematics that runs throughout the competition. ∗School of Mathematics and Physics, The University of Queensland, Brisbane QLD 4072, Australia. E-mail: [email protected] Robbie Gates (1999–2000) holds a PhD in category theory, the author (2001–2008) holds a PhD in geometry and topology, and Bernard Blackham (2009–) holds a BCM with a major in pure mathematics.