Competition Rules
Competition Days

BOI'99 competition days are Saturday April 17 and Sunday April 18. On each of these days contestants have to complete competition tasks in five hours.

Competition Equipment

For each competition round each contestant will be allowed to use one IBM PC-compatible computer.
The guaranteed configuration of the computer includes a US keyboard, mouse and colour screen.
On each competition day every contestant will be supplied with two blank formatted diskettes labeled 'A' and 'B'.
Diskettes, blank paper and all necessary forms will be available in competition room. Contestants can bring with them pens, pencils, erasers.
Using printed materials (except official BOI'99 materials), electronic devices or diskettes other then provided by the BOI'99 is prohibited.

Available software

The following software will be available on each computer:

The software will be installed in standard configuration including help files and examples.

Working directory

Working directory for both competition days is C:\BOI .


On April 16 some practice computers will be available. Configuration of these computers are the same as competition computers configuration.

The Tasks

The tasks at BOI'99 are intended to be of an algorithmic nature. That is, the focus is on designing correct and efficient algorithms.

Solution Requirements

The source code of each solution must be written in one file with name specified in the task description. As a rule, each program must read input data from an ASCII text file with name given in task description. Contestants must not include full path in file open operations. They must assume that input/output files are in the current directory (if special requirements are not stated in task description). Programs must not read any additional data nor from keyboard nor files not specified in task description. Contestants may always assume that the input data agrees with the task description. Programs must be written so that they will be executable on other computer with similar characteristics.

When we speak of 'a line of input file', this includes a terminating end-of-line. The structure of input is always such that contestant must not worry about end-of-file conditions. Input values are separated by either a single space character or a single end-of-line if it is not specified otherwise in the task description.

Programs must write their output to the ASCII text file with name specified in the task description. It is allowed to make working files during program executing in current directory.

Output on screen or contents of other files will not be evaluated. Output data must consist of sequence of items separated by space characters or end-of-line symbols as specified in task description. Contestants must not add output of their owns (even single space character).

Programs must not modify hardware and operating system structures, i.e. interrupt vectors, clock, etc. Executable code delivered as a solution must be compiled to work in 'real mode'of processor. Programs should neither expect nor depend on having any more than 500 kilobytes of free conventional memory (as reported by DOS's Mem command).


When contestants enter the competition room at the beginning of a competition round, their computers will be switched on. The competition tasks are inside an envelope next to the computer. Do not open the envelope until the start signal is given.

For each contestant task description is presented in English and in his/her native language (if such translation is prepeared by national team leader). Task description in English is binding and official.


Contestant may ask room supervisor for assistance at any time. The supervisors will NOT answer questions about the competition tasks (see Requests), but will deliver your question forms, help you find toilets, and attend to computer problems.


Contestants may submit questions, printing requests, technical problem requests.

Questions must be written on special forms available in competition room in English or in their native language. In the latter case the request will be translated into English by national team leader. Requests should be submitted to the room supervisor. Contestants may ask questions concerning the competition tasks only during the first hour of the competition. Only one of the following three answers is possible : 'Yes', 'No', 'No Comment'. All questions not related to the text of the competition tasks will be answered 'No Comment'. The Jury will answer every question submitted by contestants. This may take some time, so contestant should continue working while waiting for the answer to given question. Contestant will not be involved in discussion.

During the competition contestants will be able to get printouts of ASCII files. They must copy the file(s) into the subdirectory "PRINT" on any of given diskettes and hand it to the room supervisor. Diskette will be returned together with the printout of the file(s). File(s) after printing will be moved to subdirectory "TRASH" on diskette.

If contestants encounter problems with hardware they can submit a tehnical problem request to room supervisor. In case of hardware failure extra time will be granted to a contestant, but this will cover only the amount of time needed to replace the hardware.

Delivering the solutions

Contestants should save their solutions (i.e. both executable files and source files) onto delivered diskettes, using names specified in task descriptions. During the evaluation process the evaluator will look for the solutions on three media in the following order:

First the executable file is looked for. If it is missing the evaluator looks for the source file and compiles it using command line compiler without any switches and/or options and/or directives. If the medium is broken, the evaluator starts the above search procedure on the next medium.

Ending the competition

Contestants will be warned both 15 and 5 minutes before the end of the competition. Before the end of the competition contestants have to:

Do NOT switch off your computer. The supervisors will make backup of your work.

Evaluation process

Evaluation every competition day starts after competition end. Evaluation will be provided on separate computers with similar characteristics as contestants computer.
Evaluation of a program involves several "test runs" with confidential input data and special evaluation software. A test run for a program consists of the following steps :

The points awarded for each test run are aggregated to give final score for problem.
Delegation leader will receive a printed form with evaluation results.