my $to_col = col_letter_to_num(substr($move, 2, 1));
my $to_row = row_letter_to_num(substr($move, 3, 1));
my $promo = substr($move, 4, 1);
my $to_col = col_letter_to_num(substr($move, 2, 1));
my $to_row = row_letter_to_num(substr($move, 3, 1));
my $promo = substr($move, 4, 1);