Welcome to Genetic Reversi! Here, you can play Reversi (a.k.a. Othello) against my computer program.

UPDATE 2016-04-29: I've just changed the evaluation function, and I haven't had time to optimize the game for it yet, so it will play better a few weeks from now (right now it seems to mostly play well, but make obvious mistakes in the endgame).

How to play

You and the computer take turns placing disks on the board. The disks must be placed adjacent to one of your opponent's disks, so that the new disk, one or many of your opponent's disks, and finally one of your previous disks, form an unbroken horizontal, vertical or diagonal line. Any disks in such a line get flipped to your color. To simplify for you, in Genetic Reversi your legal moves are marked with a ring of light. The latest computer move is marked with a red background. When no player can make another move, the one with the most disks in their color wins.

Example:

Place a disk in the rightmost square...

and all the disks between your new and your old disks get flipped to your color.

About Genetic Reversi

Genetic Reversi uses alpha-beta pruning combined with a simple evaluation function that's the result of a genetic algorithm. Basically, the game looks a few moves ahead in an efficient way (how many depends on the difficulty setting), and evaluates each potential resulting board according to parameters that have been determined by letting variations of the program play against itself, and seeing which combinations of values have been the most successful.