TIMTOWDI 

use List::MoreUtils qw(uniq);
use strict;
my @array=<DATA>;

my @array=uniq(@array);
print "\n@array";

__DATA__
at12
at12
at12
at13
bn23
bn23

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In reply to Re: removing non-duplicates by gopalr
in thread removing non-duplicates by Anonymous Monk

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