def cross(self, p1, p2):
board = Board()
split = random.randint(0, p1.board.shape()[0])
for i in range(split):
board.set_row(i, p1.board.get_row(i))
for i in range(split, p1.board.shape()[0]):
board.set_row(i, p2.board.get_row(i))
board.invariants = InvariantsMerger.merge_invariants(p1, p2, self.__area_function(split))
genotype = BoardGenotype(board)
return genotype
