International Olympiad in Informatics

The International Olympiad in Informatics (IOI) is an annual competitive programming competition for secondary school students. The first IOI was held in 1989 in Pravetz, Bulgaria.

The contest consists of two days computer programming, solving problems of an algorithmic nature. Students compete on an individual basis, with up to four students competing from each participating country (with around 81 countries in 2004). Students in the national teams are selected through national computing contests, such as the Australian Informatics Olympiad, British Informatics Olympiad, and Bundeswettbewerb Informatik (Germany).

The IOI is one of the most prestigious computer science competitions in the world. UNESCO and IFIP are patrons of the International Olympiad in Informatics.

Structure of the competition

File:IOI2009 Banner.JPG

IOI 2009's banner above the competition room

On each of the two competition days, the students are typically given four problems which they have to solve in five hours. Each student works on his/her own, with only a computer and no other help allowed, specifically no communication with other contestants, books etc. Usually to solve a task the contestant has to write a computer program (in C, C++ or Pascal) and submit it before the five hour competition time ends. The program is graded by being run with secret test data. For IOI 2010, tasks are divided into subtasks with graduated difficulty, and points are awarded only when all tests for a particular subtask yield correct results, within specific time and memory limits. In some cases, the contestant's program has to interact with a secret computer library, which allows problems where the input is not fixed, but depends on the program's actions – for example in game problems. Another type of problem has known inputs which are publicly available already during the five hours of the contest. 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.

IOI 2010 will for the first time have a live web scoreboard with real-time provisional results. Submissions will be scored as soon as possible during the contest, and the results posted. Contestants will be aware of their scores, but not others', and may resubmit to improve their scores.

The scores from the two competition days and all problems are summed up separately for each contestant. At the awarding ceremony, contestants are awarded medals depending on their relative total score. The top 50% of the contestants are awarded medals, such that the relative number of gold : silver : bronze : no medal is approximately 1:2:3:6 (thus 1/12 of the contestants get a gold medal).

Front

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A bronze medal from IOI 2006 in Mexico

Unlike other science olympiads, the IOI regulations specifically prohibit ranking by countries. Although unofficial rankings are circulated within some participating nations, there is therefore no standard. Students who do not receive medals do not have their scores published, making it impossible for a country to be ranked by adding together scores of its competitors unless each wins a medal.

List of IOI websites and locations

IOI 2015 will be held in Kazakhstan, 2015
IOI 2014 will be held in Taiwan , 2014
IOI 2013 will be held in Brisbane, Australia, 2013 [1]
IOI 2012 will be held in Sirmione, Italy, September 23–30, 2012 [2]
IOI 2011 was held in Pattaya, Thailand, July 22–29, 2011 [3]
IOI 2010 was held in Waterloo, Ontario, Canada, August 14–21, 2010 [4] (results)
IOI 2009 was held in Plovdiv, Bulgaria, August 8–15, 2009 [5] (results)
IOI 2008 was held in Cairo, Egypt, August 16–23, 2008 [6] (results)
IOI 2007 was held in Zagreb, Croatia, August 15–22, 2007 [7] (results)
IOI 2006 was held in Mérida, Yucatán, Mexico, August 13–20, 2006
IOI 2005 was held in Nowy Sącz, Poland, August 18–25, 2005 [8] (results)
IOI 2004 was held in Athens, Greece, September 11–18, 2004 [9] (results)
IOI 2003 was held in Kenosha, Wisconsin, USA, August 16–23, 2003 [10] (results)
IOI 2002 was held in Yong-In, Korea Rep., August 18–25, 2002 [11]
IOI 2001 was held in Tampere, Finland, July 14–21, 2001 [12]
IOI 2000 was held in Beijing, China, September 23–30, 2000
IOI 1999 was held in Antalya-Belek, Turkey, October 9–16, 1999 [13]
IOI 1998 was held in Setúbal, Portugal, September 5–12, 1998
IOI 1997 was held in Cape Town, South Africa, November 30 – December 7, 1997
IOI 1996 was held in Veszprém, Hungary, July 25 – August 2, 1996 [14]
IOI 1995 was held in Eindhoven, The Netherlands, June 26 – July 3, 1995 [15]
IOI 1994 was held in Haninge, Sweden, July 3–10, 1994
IOI 1993 was held in Mendoza, Argentina, October 16–25, 1993 [16]
IOI 1992 was held in Bonn, Germany, July 11–21, 1992
IOI 1991 was held in Athens, Greece, May 19–25, 1991
IOI 1990 was held in Minsk, Belarus, Soviet Union, July 15–21, 1990
IOI 1989 was held in Pravetz, Bulgaria, May 16–19, 1989.

Multiple IOI winners

The following is a list of the top performers in the history of the IOI. The * sign indicates a perfect score, a rare achievement in IOI history. Also, First (I), second (II) and third (III) places among gold medalists are indicated where appropriate. This list includes only those countries where the national selection contest allows the same participant to go multiple times to the IOI.

Name	Team	Years
Gennady Korotkevich	Belarus	*G(I)** 2011	G(I) 2010	G(I) 2009	G 2008	G 2007	S 2006
Filip Wolski	Poland	G(I) 2006	G 2005	G 2004	G 2003
Martin Pettai	Estonia	G 2002	G 2001	G 2000	S 1999
Andrzej Gąsienica-Samek	Poland	G 1999	G 1998	G 1997	S 1996
Vladimir Martianov	Russia	G 1999	G(I) 1998	G(I) 1997
Martin Mareš	Czech Republic	G 1995	G 1994	G 1993
John Pardon	United States	G 2007	G 2006	G 2005
Marcin Andrychowicz	Poland	G 2008	G 2007	G 2006
Neal Wu	United States	G 2010	G 2009	G 2008
Alex Schwendner	United States	G 2005	G 2003	S 2004	S 2002
Rumen Hristov	Bulgaria	G 2011	G(II) 2010	S 2009	S 2008
Wolfgang Thaller	Austria	G 1997	G 1996	S 1999	S 1998
Bruce Merry	South Africa	G 2001	G 2000	S 1999	B 1998	B 1997	B 1996
Goran Žužić	Croatia	G 2008	G 2007	S 2009	B 2006
Victor Bargachev	Russia	G(I) 1995	G(I) 1994	S 1993
Mihai Pătraşcu	Romania	G(II) 2001	G 2000	S 1999
Roman Pastoukhov	Russia	G 2000	G(II) 1999	S 2001
Piotr Zieliński	Poland	G 1997	G(III) 1996	S 1995
Miroslav Dudík	Slovakia	G 1997	G 1996	S 1995
Richard Královič	Slovakia	G 1999	G 1998	S 1997
Tomasz Czajka	Poland (1998, 2000), United Kingdom (1999)	G 2000	G 1999	S 1998
Petr Mitrichev	Russia	G 2002	G 2000	S 2001
Luka Kalinovčić	Croatia	G 2004	G 2003	S 2002
Rostislav Rumenov	Bulgaria	G 2007	G 2006	S 2005
Vladislav Epifanov	Russia	G 2008	G 2007	S 2009
Cosmin Gheorghe	Romania	G 2009	G 2008	S 2007
Pasin Manurangsi	Thailand	G 2011	G 2010	S 2009
Wenyu Cao	United States	G 2011	G 2010	S 2009
Tzvetomir Petrov	Bulgaria	G(I) 1990	G 1993	B 1991
David Arthur	Canada	G(II) 2000	G 1999	B 1998
Janis Sermulins	Latvia	G 1999	G(II) 1997	B 1998
Teodor Tonchev	Bulgaria	G(I) 1989	G(III) 2001
Hong Chen	P.R. China	G(II) 2000	G(I) 1999
Reid Barton	United States	G(I) 2001	G 2000
Kazuhiro Hosaka	Japan	G(II) 2009	G 2008
Velin Tzanov	Bulgaria	G(III) 2002	G 2001

Open-source project for running contests:

Contest Management System Open-source tool in Python to run and manage a programming contest on a server [IOI2012].

International Olympiad in Informatics

Structure of the competition

List of IOI websites and locations

Multiple IOI winners

See also

External links