OlympiadsOlympiads Olympiads inin Informaticsin Informatics Informatics Olympiads VolumeVolume 4, Volume2010 4 4 2010 2010 B.A. BURTON. Encouraging algorithmic thinking without a computer 3 in Informatics B.A. BURTON. Encouraging algorithmic thinking without a computer 3 V.M. KIRYUKHIN. Mutual influence of the national educational standard and V.M. KIRYUKHIN. Mutual influence of the national educational standard and Olympiads in Informatics olympiad in informatics contents 15 olympiad in informatics contents 15 4 V.M. KIRYUKHIN, M.S. TSVETKOVA. Strategy for ICT skills teachers and V.M. KIRYUKHIN, M.S. TSVETKOVA. Strategy for ICT skills teachers and informatics olympiad coaches development 30 informatics olympiad coaches development 30 M. KUBICA, J. RADOSZEWSKI. Algorithms without programming 52 M. KUBICA, J. RADOSZEWSKI. Algorithms without programming 52 I.W. KURNIA, B. MARSHAL. Indonesian olympiad in informatics 67 I.W. KURNIA, B. MARSHAL. Indonesian olympiad in informatics 67 K. MANEV, B. YOVCHEVA, M. YANKOV, P. PETROV. Testing of programs K. MANEV, B. YOVCHEVA, M. YANKOV, P. PETROV. Testing of programs with random generated test cases 76 with random generated test cases 76 B. MERRY. Performance analysis of sandboxes for reactive tasks 87 B. MERRY. Performance analysis of sandboxes for reactive tasks 87 P.S. PANKOV. Real processes as sources for tasks in informatics 95 P.S. PANKOV. Real processes as sources for tasks in informatics 95 M. PHILLIPPS. The New Zealand experience of finding informatics talent 104 M. PHILLIPPS. The New Zealand experience of finding informatics talent 104 T. TOCHEV, T. BOGDANOV. Validating the security and stability of the grader Volume 4, 2010 T. TOCHEV, T. BOGDANOV. Validating the security and stability of the grader for a programming contest system 113 for a programming contest system 113 M.S. TSVETKOVA. The olympiads in informatics as a part of the state program M.S. TSVETKOVA. The olympiads in informatics as a part of the state program of school informatization in Russia 120 of school informatization in Russia 120 T. VERHOEFF. An enticing environment for programming 134 T. VERHOEFF. An enticing environment for programming 134 H. WANG, B. YIN, R. LIU, W. TANG, W. HU. Selection mechanism and task H. WANG, B. YIN, R. LIU, W. TANG, W. HU. Selection mechanism and task creation of Chinese national olympiad in informatics 142 creation of Chinese national olympiad in informatics 142 E. ZUR, T. BENAYA, D. GINAT. IOI Israel – team selection, training, and statistics 151 E. ZUR, T. BENAYA, D. GINAT. IOI Israel – team selection, training, and statistics 151 W. POHL, B.A. BURTON, V. DAGIENE,˙ J. FAKCHAROENPHOL, M. FORIŠEK, W. POHL, B.A. BURTON, V. DAGIENE,˙ J. FAKCHAROENPHOL, M. FORIŠEK, M. HIRON, M. OPMANIS, B. SKUPAS,¯ W. van der VEGT. Get involved! M. HIRON, M. OPMANIS, B. SKUPAS,¯ W. van der VEGT. Get involved! The IOI workshop 2010, its goals and results 158 The IOI workshop 2010, its goals and results 158 IOI IN INFORMATICS 0868-4952(2010);1-Q LYMPIAD ISSN 1822-7732 0868-4952(2010);1-Q O INTERNATIONAL ISSN 1822-7732 INTERNATIONAL OLYMPIAD IN INFORMATICS INSTITUTE OF MATHEMATICS AND INFORMATICS INTERNATIONAL FEDERATION FOR INFORMATION PROCESSING OLYMPIADS IN INFORMATICS Volume 4 2010 Selected papers of the International Conference joint with the XXII International Olympiad in Informatics Waterloo, Canada, August 14–21, 2010 OLYMPIADS IN INFORMATICS ISSN 1822-7732 Editor-in-Chief Valentina Dagien˙e Institute of Mathematics and Informatics, 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 Instituteof 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 Fredrik Niemelä, KTH University, Sweden, [email protected] Rein Prank, University of Tartu, Estonia, [email protected] Miguel A. Revila Ramos, University of Valladolid, Spain, [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: Institute of Mathematics and Informatics c Institute of Mathematics and Informatics, 2010 Akademijos 4, LT-08663 Vilnius, Lithuania All rights reseserved Olympiads in Informatics, 2010, Vol. 4 © 2010 Institute of Mathematics and Informatics, Vilnius Foreword Informatics and technology in general are curious endeavours in which to be involved. Working, researching or teaching within them, on a day to day basis, they seem to move quite slowly. Step back however and look a few years in the past and the pace of change can be staggering. And not just recent memory. It is a fair bet that this has been true for everyone reading this, whatever their age, country or time in their life when the statement might have been made. Education also has its trends and its technologies. The internet, email and technology in general have brought new means of communication and access to information. The teaching of informatics has changed as new technologies are introduced, but so has the teaching of other subjects. Computers are no longer just for the specialist – they are basic tools. The papers in this volume cover a range of topics. Some are specific to informatics but some are about education in general. Not just the way we are influencing it, but how it is influencing us. Government policies to educate all teachers and students, if not entire populaces, in what was not long ago not experienced by most. There are papers considering alternative ways of teaching informatics and getting students thinking about algorithms. Papers on tasks and evaluation, looking at how (and indeed from where) we create quality tasks with a pedagogical benefit. Papers on communication and the sharing of resources. We are fortunate to have an enthusiastic, if small, community. The recent IOI workshop is briefly reported in this volume and longer papers will follow in the future. The editorial board has been expanded and by bringing in individuals from outside the IOI we intend to enlarge the scope of the journal. Small steps perhaps, but step back in a few years time... As always thanks are due to all those who have assisted with the current volume – authors, reviewers and editors – and it would be remise not to thank those involved in arranging the workshop and encouraging research. Particular thanks are due to the organisational committee for IOI’2010 in Canada without whose assistance we would be unable to hold the conference. Their assistance, during what is an already busy period, is gratefully received. Editors Olympiads in Informatics, 2010, Vol. 4, 3–14 3 © 2010 Institute of Mathematics and Informatics, Vilnius Encouraging Algorithmic Thinking Without a Computer Benjamin A. BURTON School of Mathematics and Physics, The University of Queensland Brisbane QLD 4072, Australia e-mail: [email protected] Abstract. At the secondary school level, traditional programming competitions remain inaccessible to the vast majority of students. We describe the Australian Informatics Competition (AIC), a pen- and-paper event that is accessible to a much broader audience but still retains a core focus on algorithms. In addition to multiple choice questions, a unique feature of the AIC is its three-stage tasks that invite algorithmic thinking by posing similar problems of increasing size. In this paper we describe the AIC, the design decisions behind it, and the types of problems that it contains. Key words: multiple choice contests, algorithmic tasks, three-stage tasks. 1. Introduction Competitions and enrichment programmes in computer science have enjoyed a sharp rise in popularity over recent decades. Consider for instance the International Olympiad in Informatics (IOI) – although much younger than many of the science olympiads, the IOI has grown to become the second largest of these international events.1 Non-competitive programmes have also enjoyed an enthusiastic reception, such as Australia’s National Computer Science School (http://www.ncss.edu.au/). Despite this popularity, many national informatics olympiad programmes struggle to find students at the secondary school level (Anido and Menderico, 2007; Boersen and Phillipps, 2006; Choijoovanchig et al., 2007; Pohl, 2007). In Australia the numbers are striking – the national entry-level mathematics competition enjoys several hundred thou- sand participants each year, whereas the entry-level programming competition for the informatics olympiad attracts just one or two hundred. Several factors contribute to these extremely low rates of entry for national program- ming competitions: (i) Curriculum: In many countries, computer programming and algorithm design re- ceives very little attention in the secondary school curriculum (Verhoeff, 2009). In comparison, mathematics and other science olympiad disciplines (such as biol- ogy, chemistry and physics) are well-taught and widely studied. As a result, there 1Measured by the number of attending countries in 2009. 4 B.A. Burton are far fewer students with the necessary skills for a programming competition; moreover, it is difficult for teachers