Drawless square board orthogonal connection game with gripping ko fights.

DEFINITIONS

A crosscut is a 2x2 pattern of stones consisting of two diagonally adjacent black stones and two diagonally adjacent white stones.

PLAY

Black plays first, then turns alternate. On your turn, you will face one of these situations:

a) There are no crosscuts on the board. In this case, you must place a stone of your color on an empty point of the board such that it forms no crosscuts containing a stone that was placed by the opponent on their latest turn. If there is no such placement available, you must pass. Passing is otherwise not allowed.

b) There are one or more crosscuts on the board. In this case, you must take a friendly stone from one of those crosscuts and place it on a different empty point where it doesn't create any other crosscuts. If no such point exists, the stone is simply removed from the board.

The game is won by the player who completes a chain of orthogonally adjacent stones of their color touching the two opposite board edges of their color. Draws are not possible.

In this implementation, the program only checks the winning condition on the 3x3, 4x4 and 5x5 boards.