DEDUCTION

Deduction is a classy ST BASIC adaptation of the old game most recently popularized as Master Mind. You must guess a pattern of four colors chosen by the computer. Each color can occur only once in the sequence. The game's concept is ancient, having been played in old England as Cows and Bulls, and more recently as Code-Breaker.

First type in DEDUCT.BAS, checking with ST TYPO, and SAVE a copy before you RUN it. Load ST BASIC and click on BASIC.PRG. Then load DEDUCT.BAS and click on "Run" in the appropriate window. This calls up a low-resolution color screen that interacts with the user via the mouse. (Sorry, Deduction does not run on the ST's high-resolution monochrome monitor.)

To begin deducing, click on the left button for the easy version of the game, or right button for the hard version. Both versions give you a choice of red, yellow, green, blue, cyan and violet. But the hard version also adds pink. This might not sound like a big difference, but with six colors, the odds are one in 360 that you'll get it right the first time. Adding a seventh color raises the odds to one in 840.

This pattern was deduced in eight moves. It's not always so easy.

12 TRIES
You get 12 chances to guess the correct sequence. After you click on a color, that color is copied above in the first open rectangle on the left. Click on "Accept"-or "Reject" if you change your mind. The squares to the right of the four rectangles change color to indicate how close your guess was. White squares show that you got a color right, but in the wrong sequence. Black squares indicate that both the color and sequence are right.

From this, you can probably see that those high odds decrease drastically as you play-if you use your head. If you see two white squares, one black and one blank, you know that three colors are correct, but only one is in the right place. From there, you can see how that guess relates to previous guesses. Once you know where a color isn't, you should be able to piece the puzzle together and determine where each color is.

But Deduction isn't a piece of cake. Just guessing randomly won't do. You might even try keeping track of your deductions on paper to help you see a pattern. But if you just work it all out in your head, you're still likely to guess correctly within 12 turns-if you play the game right.

Deduction follows last month's Hangman in a series of classic public domain games revamped for ST BASIC by Stephen Everman and Paul Pratt of Hayward, California. Their flashy version of Star Trek will appear in the February, 1986 issue of Antic.

Listing 1: DEDUCT.BAS Download