Hip is a game invented by the mathematician Martin Gardner.


The game is played on a NxN square. The board starts empty


Each player place stone on any unoccupied square.
The goal is to avoid completing any square by marking all 4 corners with stone on the same color. The square may be any size and tipped at any angle. On 6x6 board there is 105 such squares. The n x n board has n * n * (n * n - 1) / 12 squares. The first player to complete a square is the loser.


Classic Hip is solved game - the second player is winner. To win 2nd player need play the reflection of the 1st player's moves.
There are different ways io avoid this problem.