Informatica

The results of investigation of computer programs written by school students during the 6th International Olympiad in Informatics are presented. Pascal program texts are analyzed on the lexical level. A certain relationship is indicated between program correctness and usage of some programming constructs as well as readability of the program text. The results are discussed from the standpoint of programming teaching.

The paper deals with a simple model of the competition of two queuing systems, providing the same service. Each system may vary its service price and its service rate. The customers choose the system with less total service price, that depends on the waiting time and on the service price. The possibility for the existence of equilibrium is investigated. Simple cases are investigated analytically. It is shown that the Nash equilibrium exists in special cases only. A modification of the Stakelberg equilibrium is proposed as a model of competition with a prognosis. This prognosis helps form more stable prices and more stable strategies of competitors. The case of social economics is investigated, too. The dynamics of the competition of more realistic stochastic queuing systems is investigated by Monte Carlo simulation. The simulative analysis is realized by means of a rule-based simulation system.

A development of algorithms and writing of programs are considered as closely related but not identical parts of computer programming. Some differences between them are important for learning of computer programming, in particular, in distance learning. These differences are identified and discussed from the pedagogical point of view. The arguments for the selection of pedagogical based and cost-effective delivery modes in the case of distance learning are investigated. Practical examples supporting theoretical arguments are given on the activities of Lithuanian schools.

An algorithm testing methodology used in the programming teaching process is presented. Turbo Pascal system is used. Due to systematic use of some features of this system a pseudo-direct execution of algorithms expressed by Pascal procedures and functions may be ensured. The need to use data read and write statements is excluded. This enables a novice learner to concentrate himself on the main actions of an algorithm.

The role and goals of computer programming in the education of young people are discussed. The activity of the Lithuanian Young Programmers School by correspondence is described. Motivation of its curriculum and the way of teaching are given. Relations with the competitions of programmers and some other forms of teaching are considered.