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Olympiads in Informatics 6 Algorithm Design with Pythia, a Web-Based Learning Platform 31 D Olympiads Olympiadsin Informatics in Informatics Olympiads VolumeVolume 6, 2012 6 2012 G. AUDRITO, G.B. DEMO, E. GIOVANNETTI. The role of contests in changing informatics education: a local view 3 in Informatics V. BOŽA, M. FORIŠEK. FCL-STL, a generics-based template library for FreePascal 21 S. COMBÉFIS, V. le CLÉMENT de SAINT-MARCQ. Teaching programming and Olympiads in Informatics 6 algorithm design with Pythia, a web-based learning platform 31 D. GINAT. Insight tasks for examining student illuminations 44 S. HALIM, Z.C. KOH, V.B.H. LOH, F. HALIM. Learning algorithms with unified and interactive web-based visualization 53 M. HIRON, L. FÉVRIER. A Self-paced learning platform to teach programming and algorithms 69 S. MAGGIOLO, G. MASCELLANI. Introducing CMS: a contest management system 86 M. MAREŠ, B. BLACKHAM. A new contest sandbox 100 P.S. PANKOV, K.A. BARYSHNIKOV. Tasks of a priori unbounded complexity 110 N. RAGONIS. Type of questions – the case of computer science 115 REPORTS 133 F. ALMEIDA, V. BLANCO PÉREZ et al. An experience on the organization of the first Spanish parallel programming contest 133 F. DOGBEY. Learning computer programming as an extra curriculum activity, Volume 6, 2012 the challenges 148 A. ILIC,´ A. ILIC.´ IOI Training and Serbian competitions in informatics 158 J.R. JANALIEVA. Conducting off-line informatics olympiads with individual tasks 170 E. KELEVEDJIEV, Z. DZHENKOVA. Competitions’ tasks in informatics for the “pre-master” group of school students 178 P. NEDKOV. Young talent in informatics 192 P. TAYLOR. Comparisons of the IMO and IOI 199 J. URBANCIˇ C,ˇ M. TRAMPUŠ. Putka – a web application in support of computer programming education 205 W. van der VEGT. Theoretical tasks on algorithms; two small examples 212 E. ZUR, T. BENAYA, O. BECKER, D. GINAT. Israel: The regional competition and teacher involvement 218 REVIEWS, COMMENTS 226 Ics In Informat IOIIad olymp Ional ISSN 1822-7732 Internat ISSN 1822-7732 INTERNATIONAL OLYMPIAD IN INFORMATICS VILNIUS UNIVERSITY INSTITUTE OF MATHEMATICS AND INFORMATICS OLYMPIADS IN INFORMATICS Volume 6 2012 Selected papers of the International Conference joint with the XXIV International Olympiad in Informatics Sirmione – Montichiari, Italy, September 23–30, 2012 OLYMPIADS IN INFORMATICS ISSN 1822-7732 Editor-in-Chief Valentina Dagiene˙ Vilnius University, Lithuania, [email protected] Executive Editor Richard Forster British Informatics Olympiad, UK, [email protected] International Editorial Board Gerald Futschek, Vienna University of Technology, Austria, [email protected] Bruria Haberman, Holon Institute of Technology, Israel, [email protected] Marcin Kubica, Warsaw University, Poland, [email protected] Ville Leppänen, University of Turku, Finland, [email protected].fi Krassimir Manev, Sofia University, Bulgaria, [email protected]fia.bg Rein Prank, University of Tartu, Estonia, [email protected] Peter Taylor, University of Canberra, Australia, [email protected] Troy Vasiga, University of Waterloo, Canada, [email protected] Peter Waker, International Qualification Alliance, Republic of South Africa, [email protected] http://www.mii.lt/olympiads_in_informatics Publisher: Vilnius University Institute of Mathematics and Informatics c Vilnius University, 2012 Akademijos 4, LT-08663 Vilnius, Lithuania All rights reseserved Olympiads in Informatics, 2012, Vol. 6, 1–2 1 © 2012 Vilnius University Foreword Writing the introductions to the successive volumes of Olympiads in Informatics gives a moment to reflect. Typically on the changing face of informatics olympiads and educa- tion but also informatics and wider society in general. In the time between the previous (5th) conference and this one, back in October 2011, one of the pioneer computer sci- entists passed away. This was someone whose work had a noticeable influence on most informatics olympiads, indeed on much of computing as we know it today, and someone whose death whilst making the obituary columns in many major papers rarely made it any further. Quickly forgotten, or passing under most peoples’ radar, a man without whom the current IT landscape would look somewhat different. We refer, of course, to Dennis Ritchie whose contributions included such things as the UNIX operating system and the C language. It is perhaps telling that almost all informat- ics olympiads – excluding perhaps those aimed at a relatively junior level – include C or its successors as programming options. On receiving the US National Medal of Tech- nology he, along with his co-recipient, said “We take this award to us as symbolic of the seminal contributions of our immediate colleagues ...manyofthemostinterestingideas were not ours, but generated in collaboration”. It would be easy to focus on the “collaboration” statement. We are, after all, a confer- ence so our very existence relies on collaboration within our community. Individuals to write the papers, review them, edit them and of course read and use them, without which they are but “sound and fury, signifying nothing”. Rather, let us reflect on the “seminal contributions”. Our field is a relatively young one, one which leaving aside its mathematic roots (claiming the 300 BCE Euclidean algorithm as evidence for computer science exist- ing for over 2 millennium would be stretching a point) and some programable machines in the 1800s, really kicked off in the 1930s. Some of the early pioneers are still amongst us and many of us have worked with and known others. Our up-and-coming computer scientists have that opportunity to be pioneers in the field. Our informatics olympiads are a means for capturing and enthusing potential stu- dents; to quote the IOI regulations “To bring the discipline of informatics to the atten- tion of young people”. We all have different requirements when putting together our olympiads. We want to attract a wide range of students, introduce real computing to students who otherwise only see the end results; the games they play and the word pro- cessing they are ’taught’ in schools. We are also there though for our best students – our participation at global olympiads proves that point. How do we encourage those students? Our best students are often the best students in a multitude of subjects – why should they choose informatics? How do we grab our new pioneers? 2 Informatics in general is young and the teaching of informatics, plus teaching with informatics, younger still. We have opportunities, in many of our countries, to have an impact – positive or negative – on the way students are taught. Get it right and paradigms for future teaching will be set; a pioneering footstep. Get it wrong and we will just a part of a passing trend; an inevitable footnote. This volume is quite extensive: we are publishing 22 papers and reports. The format for the journal follows three tracks: the primary section of the journal focuses on research (the acceptance rate is around 40%); the second report section is devoted to sharing our national experiences – potentially of less interest to those outside the community; the last section presents some book reviews which we hope will be of interest to our readers. We are pleased that this volume succeeded in getting national reports from various countries. Again, we would like to encourage writing short comments, opinions and challenges – it will be useful for everybody within community. As always thanks are due to all those who have assisted with the current volume – authors, reviewers and editors. A lot of work goes, not only to the writing of the papers, but to an extended period of review and correction and, in several cases, translation. Peer reviewing all of the papers takes a significant amount of time and work and special thanks should be given to those otherwise unsung reviewing heroes: Ian W. Atha, Jonas Blonskis, Ben Burton, Giorgio Casadei, Sebastien Combefis, Hugo Duenas, Gerald Futschek, Gin- tautas Grigas, Sari Haj Hussein, Ville Leppänen, Krassimir Manev, Timo Poranen, Rhein Prank, Jurat¯ eSk˙ upien¯ e,˙ Peter Taylor, Ahto Truu, Troy Vasiga, Willem van der Vegt, and Peter Walker. Last, but by no means least, particular thanks are due to the organisational committee for IOI’2012 in Italy without whose assistance we would be unable to hold the confer- ence. Their assistance, during what is an already busy period, is gratefully received. Editors Olympiads in Informatics, 2012, Vol. 6, 3–20 3 © 2012 Vilnius University The Role of Contests in Changing Informatics Education: A Local View Giorgio AUDRITO1,G.BarbaraDEMO2, Elio GIOVANNETTI2 1Dipartimento di Matematica, Università di Torino via Carlo Alberto, 10-10123 Torino, Italy 2Dipartimento di Informatica, Università di Torino corso Svizzera, 185-10149, Torino, Italy e-mail: [email protected], {barbara, elio}@di.unito.it Abstract. Changing the teaching of informatics in secondary (and primary) education is in many countries difficult to achieve, owing to several reasons: the natural tendency of institutions and people to stick to well-established practices, a distorted view of informatics prevailing in society and among those who take the decisions, the specific fact that in several school systems the teaching of informatics is largely committed to teachers of other scientific disciplines. We describe the Italian situation and our experience in Turin where we have organised training stages for the Olympiad in Informatics and supported the organisation of other informatics contests. On its basis we argue how the different kinds of competition can help to change informatics education in Italy, by making problem solving and programming play a central role. Key words: competitions, problem solving, programming in education, data structures, algorithms, programming techniques. 1. Introduction In the last few years the need for a change in curricula, learning objectives and teach- ing techniques of computer-related disciplines in (primary and) secondary education has emerged in the public debate in a number of countries. The recent speech of the British Secretary of State for Education Mr. Michael Gove at BETT 2012 (BETT is the annual British Educational Training and Technology show) is a good example of governmental awareness on the subject.
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