my @ids = do { @ARGV || -t STDIN ? @ARGV : <STDIN> };
chomp @ids;

##</code><code>##

my $fh;
if (@ARGV || -t STDIN) {
    open $fh, '<', \ join("\n", @ARGV);
}
else { $fh = *STDIN }
while (defined(my $id = <$fh>)) {
    chomp $id;
}