open(MYFILE, $data_file) || die("Could not open file!");
 {
my $energy;
while ( <MYFILE> ) {
    if ( /\bENERGY\b/ ) {
        ++$energy;
        next;
       }
	   
    my ( $key, @fields ) = grep $_, split;
    for my $field ( @fields ) {
	if ( $field ne 'G' && $field ne 'A' && $field ne 'C' && $field ne 'G' )
	{
        print WRITE "$key $field $energy\n";
        }
    }
	}
	}
close(MYFILE);