Select Code to Download

foreach my $key (grep { !m/\t0$/ } keys %data) {
    my ($chr, $fivep, $threep, $strand) = split m/\t/ => $key;
    say join "\t" => $chr, $fivep, $threep, "-",
        map { $data{$key}{$_} // 0 } @files;
    }

use Text::CSV_XS qw( csv );

...
foreach my $key (sort keys %c7) {
    say join "\t" => (split m/:/ => $key), map { $c7{$key}{$_} // 0 } 
+@files;
    }