#!/usr/bin/perl
use strict;
use warnings;
use 5.010;

my @tracks = map {open  my $track, ">", $_ or die "Can't open $_: $!"; $track}
    'track1.txt', 'track2.txt', 'track3.txt';

for my $track (@tracks){
    print <$track>;
}

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;
use 5.010;

my @tracks =
    (['track1.txt', 1000], ['track2.txt', 5000], ['track3.txt', 20000]);

for my $track (@tracks) {
    open my $trackFile, ">", $track->[0] or die "Can't open $track->[0]: $!";
    $track = [$trackFile, $track->[1]];
}

for my $track (@tracks) {
    my ($trackFile, $lines) = @$track;
    print <$trackFile>;
}