The IOI 2012 Competition


Tasks and Solutions

Day 0 (Practice session) – 24 September 2012


Day 1 – 25 September 2012

Task descriptions:

Some hints.


Day 2 – 27 September 2012

Task descriptions:

Some hints.


Contest Data for Tasks

Download task directories, test data and more (tgz, 167 Mb)



The author of “Pebbling odometer” and “Parachute rings” is Michal Forišek, with subtasks 5 of “Pebbling odometer” by Giovanni Paolini and its solution by Matteo Boscariol. The author of “Crayfish scrivener” is Bruce Merry. The authors of “Ideal city” are Aleksandar Ilić and Andreja Ilić. The author of “Last supper” is Richard Královič. The author of “Jousting tournament” is Luke Harrison. The task writeup and stories are by Paolo Boldi and Roberto Grossi. Final version of tasks reviewed by ISC members, Bernard Blackham, and team leaders. Practice task “Olympic pizza” is by Luca Wehrstedt, and “Italian queue” and “Touristic plan” are by Giovanni Paolini.

Solutions, generators and/or graders written by Matteo Boscariol, Massimo Cairo, Giovanni Campagna, Stefano Maggiolo, Giovanni Mascellani, Giovanni Paolini, Luca Wehrstedt. Hints by Paolo Boldi.

Contest management system (CMS) by Matteo Boscariol, Stefano Maggiolo, Giovanni Mascellani, Luca Wehrstedt, with contributions by Bernard Blackham. Translation system by Stefano Maggiolo and Luca Wehrstedt, with technical support by Martin Mareš and Bernard Blackham. Task manager: Giovanni Paolini. Translation manager: Stefano Maggiolo. System manager: Giovanni Mascellani.

We thank the following people who provided additional beta-testing for the tasks: Giorgio Audrito, Dario Cazzaro, Alessio Guerrieri, Filip Hlásek, Jui-Min Lee, Jakub Zíka.

We are grateful to the authors of the submitted tasks: Osman Ay, Kirill A. Baryshnikov, Massimo Cairo, Sébastien Combéfis, Kazuhiro Hosaka, Irvan Jahja, Francisco Javier Zaragoza Martinez, Sergey Melnik, Slobodan Mitrovic, Jonathan Mosheiff, Gerhard Niederbrucker, Rihards Opmanis, Pavel S. Pankov, Giovanni Paolini, Ronald Ping Man Chan, Ferran Alet Puig, Saeed Seddighin, Aram Shatakhtsyan, Monika Steinová, Wenbin Tang, Velin Tzanov, Normunds Vilciņš.