An implementation of an AI algorithm for tic tac toe. It is based on the 8 following rules pf the perfect player.
1.Win: If the player has two in a row, he or she can place a third to get three in a row. 2.Block: If the [opponent] has two in a row, the player must play the third himself or herself to block them. 3.Fork: Creation of an opportunity where the player has two threats to win (two non-blocked lines of 2). 4.Blocking an opponent's fork: Option 1: The player should create two in a row to force the opponent into defending, as long as it doesn't result in them creating a fork. For example, if "X" has a corner, "O" has the center, and "X" has the opposite corner as well, "O" must not play a corner in order to win. (Playing a corner in this scenario creates a fork for "X" to win.) Option 2: If there is a configuration where the opponent can fork, the player should block that fork. 5.Center: A player marks the center. (If it is the first move of the game, playing on a corner gives "O" more opportunities to make a mistake and may therefore be the better choice; however, it makes no difference between perfect players.) 6.Opposite corner: If the opponent is in the corner, the player plays the opposite corner. 7.Empty corner: The player plays in a corner square. 8.Empty side: The player plays in a middle square on any of the 4 sides.