The Art of Amazement

Transcribed from the printed issue; not yet reviewed. Read it in the PDF of the issue, page 60

Review of article in the Guardian, 13 December 1991

APL featured in the Computer section of the Guardian last December with an article about mazes. Adrian Fisher, of Minotaur Designs, has been experimenting with maze designs and has come up with a new variant: colour mazes. Colour mazes require the walker to change colour at every junction, making it more difficult to plot a route. The traditional maze increases difficulty by restricting the view of the overall plan with high hedges. A colour maze may allow an overall view and still be sufficiently difficult to make it fun.

An example of a three-coloured maze would be one with a traffic light sequence of colours: red, yellow and green. Say you start on red. At the first junction only the yellow can be followed according to the rules. This leads to the next junction where a choice of two green routes is offered, plus a yellow path which cannot be taken. If there was no red line to this junction then this would be a dead end if you entered it on one of the green lines.

It is simple to ensure that every node has all the possible colours entering it, but it is very difficult to determine if there are any ‘black holes’ from which there is no escape, particularly if the ‘black hole’ involved a lengthy sequence of moves.

Anthony Camacho developed a maze testing program, using Sharp APL on a PC, which checks out proposed mazes prior to it being laid out for real. Anthony presented a paper about his work at the APL 89 conference. Reading the Conference Proceedings after having read the Guardian article is quite interesting as one can recognise the origin of some of the wording! Obviously the Proceedings go into much more detail than would be possible in the Guardian, but it was surprising how much one could glean from the article.

Adrian Fisher has written a book on mazes, The Art of the Maze, published by Weidenfeld & Nicolson at £18. The Guardian article did not exactly review the book, but it certainly gave the impression that it would be a well worth while purchase for anyone interested in mazes.