Fernando, the database is generated starting by assembling all of the checkmate positions first. From each of these, you generate legal moves "in reverse". That means, you "undo" one move, then it is the mating side to move, and the move you undid must lead to a mate in 1 since the parent position was a checkmate. From all of these mate in 1 positions, you have the other side try to avoid entering the position. If every legal move leads to the mate in 1, then that side to move is mated in 2, etc.

From the parent position, I did not generate king moves, which means should the white king have been able to move and REVEAL a check of the bishop that resulted in a checkmate, that position was not assigned a "mate in 1" value. Since everything else in the database depends on all of this information, it has to be recomputed.

To enter the contest, just tell me where you want to place a knight, bishop and king that results in the longest checkmate of an enemy king, The board has 80 squares, a1 through j8. Good luck in the contest.

--Ed