Drawless square board orthogonal connection game where resolution of diagonal connections is forced and costs a whole turn.

DEFINITIONS

A weak pair is a set of two like-colored, diagonally adjacent stones such that there is no like-colored stone orthogonally adjacent to both.

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, if there are any friendly weak pairs on the board, you must place a stone of your color on an empty point that is orthogonally adjacent to the two stones in one of those pairs. If there are no such pairs, you must place a stone of your color on any empty point.

After placing a stone, you must remove all other friendly stones that are part of any crosscuts. The stone you just placed is not removed.

OBJECTIVE

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

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