Example program solving BIO'99 Round One Question 1

Your Browser seems to have no Java support. Please get a new browser or enable Java to see this applet! To see this solution, you need a browser that is able to run Java applets. Alternatively, follow the instructions at the end of this page for how to run the program outside your browser.

To run the program:

  1. Click on the 'Start BIO99R1Q1App' button. The program is now running.
  2. Click inside the text window to activate keyboard input to the program.
  3. Type in your input as required by the program.
  4. To re-run the program click on the button to 'Stop' the program, then click 'Start' again.
The application asks you to type in a number. It then finds the value at which the digital river starting from this number reaches one of the rivers 1, 3 or 9. If you type a negative number, the solution to 1 (b) is calculated.

BIO'99 Round One
BIO 2000 Sample paper

Running the program with Java outside a browser

If you have a Java runtime interpreter installed on your computer, you can run the program without using a browser. You need to download the files BIO99R1Q1App.class and AppletConsoleApp.class to your computer. In the directory containing these files, execute the application BIO99R1Q1App.class with the command
java BIO99R1Q1App.class
substituting the name of your Java runtime interpreter for java. Alternatively, follow the instructions given in your Java documentation.

Obtaining a Java runtime interpreter

Free Java runtime interpreters are available for most major computer systems. See Sun's Java website for details (look for 'Java Runtime Environment').


Solution copyright (c) 1999 The British Informatics Olympiad (BIO).

This program may be freely copied by persons or organisations involved in the British Informatics Olympiad or the International Olympiad in Informatics, on condition that no changes are made and this notice is not altered. Distribution for profit is forbidden unless permission is first obtained in writing from the BIO.

This program is for educational purposes only and comes with no warranty, implied or otherwise, as to its fitness for any purpose.

Author: Antony Rix
Internet: http://www.christs.cam.ac.uk/bio/
E-mail: (see contact details from home page)
S-mail:
The British Informatics Olympiad
Christ's College
Cambridge CB2 3BU
United Kingdom

The British Informatics Olympiad