use strict;
use warnings;

my $filename = $ARGV[0];
my %gene_count;

open my $fh, '<', $filename or die "Cannot open $filename: $!";

while ( my $line = <$fh> ) {
	chomp;
	my @row = split( "\t", $line );
	$gene_count{ $row[18] }++ if $row[18];
}

close($fh);

print "$_ => $gene_count{$_}\n" for sort keys %gene_count;

##</code><code>##

use strict;
use warnings;

my %gene_count;

while (<>) {
	my @rows = split ' ', $_, 20;
	$gene_count{ $row[18] }++ if $row[18];
}

print "$_ => $gene_count{$_}\n" for sort keys %gene_count;