Let me guess ... you've programmed in other languages before. ;-)

First - $lino. Looks like a duplicate of $. (see perlvar).

The @{} isn't needed in your $atom assignment: $lines[$.][$blip++] = $atom works fine. Although $lines[$.] = \@div works even better than using the foreach at all.

As pointed out by sk, you really want to use a hash to detect duplicates. Personally, I like as much info as possible, so I'd do something like this: 

my %whole_file;
while (<ADDS>)
{
  my %info = (
    line_number => $.,
    line_text   => $_,
    atoms       => split /\t/
  );
  $info{key} = $info{atoms}[1];
  push @{$whole_file{$info{key}}}, \%info;

  # you can print out a tick every 100 or whatever here, using $.
}

my @dupes = grep { scalar @$_ > 1 } values %whole_file;

# to see what data structure I just built, dump it via your favourite 
+dumper.  Mine is:
use Data::Dumper;
print Dumper(\@dupes);

[download]
With all that info, I can do whatever I want no matter how flexible my requirements need to be, no matter what changes my boss sees fit to throw at me.

In reply to Re: Oddly growing array by Tanktalus
in thread Oddly growing array by arsoncupid

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