By HEATH LAWRENCE

Faces, houses, telephones, musical notes, helicopters and spacemen are only a few of the pictures that kids can match in this 342-square memory game modeled after TV's famed "Concentration." The BASIC program works with all Atari 8-bit computers of any memory size, disk or cassette.

In this brain-challenging game, two players compete to be first to match 10 pairs of little pictures hidden behind 19 rows and 18 columns of blank blocks. That's a total of 342 possible hiding places and the pictures are randomly scattered into different positions every time you play the game. So you'll need to focus all your memory skills.

Unlike the other variations of TVs "Concentration" we have published in recent months-BASIC Concentration ST (April 1988) and 8-bit Recall (May 1988)-Sleuth does NOT require players to guess words after finding the image pairs. Therefore, Sleuth is a particularly suitable challenge for families with kids who don't read yet.

GETTING STARTED

Type in Listing 1, SLEUTH.BAS, check it with TYPO II and SAVE a copy before you RUN it. This two-player program works with either two joysticks (each player uses their own), or with one joystick shared by both players in turn.

When RUN, Sleuth asks you whether you're using one joystick or two. Next, Sleuth draws a black-bordered 18 X 19 grid and a little "man" at both bottom comers of the screen.

Each player then takes turns moving the flashing cursor from the center of the screen to any other square in the grid. Pressing the joystick button reveals a yellow icon. You then move to another square and press the button again.

If you uncovered a pair of icons, they'll both turn green and remain onscreen. If the two icons don't match, there's an onscreeen countdown of 10 seconds and you must try to memorize the icon locations before they're covered up again.

A match is worth one point and will make your little man jump joyfully at the bottom of the screen. After one player gets 10 points and wins, a star appears below the winner's jumping man. Press [START] for another game.

HINTS

The key to winning at Sleuth is to remember the positions of shapes that were revealed a few turns previously. It's much easier to remember icon locations if you use points of reference. For instance, try exposing icons in the corners or beside others that were matched previously. Pay particular attention to the locations during the 10-second countdown-you can bet that your opponent will.

To change the cursor speed, change the variable D in line 170 ("FOR D = 1 TO 20:NEXT D"). To change the countdown time, do the same thing in line 60.

PROGRAM TAKE-APART

10-20 Call the initialization routines.

40-140 Call the move-cursor routine. Check for a match and a winner-if there is a match, increment the score. Otherwise, begin the countdown.

160-210 Check the joystick for cursor movement. Check the trigger. Adjust the to cursor's position and redraw it.

230-240 Move the Player/Turn indicator.

260 Indicate the winner and animate that player's man.

280-290 Reveal the icon beneath the present cursor position.

310-330 Indicate a match by making the player's man jump.

350-390 Initialize variables, create the playfield.

410-440 Display the title screen and redefine the character set.

460-520 DATA for icons.

FOR MORE ARTICLES LIKE THIS, CIRCLE 202 ON READER SERVICE CARD.

Listing 1: SLEUTH.BAS Download