If you don't care how you get the results, then this works (if I read your problem statement correctly). It uses List::Compare from CPAN. 
#!usr/bin/perl
use strict;
use warnings;
use feature 'say';
use Data::Dumper::Simple;
use List::Compare;

my @dead_list = (100,
            101,
            103,
            200,
            201,
            202,
            203,
            210,
            211,
            212,
            220,
            221,
            222,
            230,
            231,
            232,
            233,
            240,
            241,
            242,
            243,
            1000,
            1001,
            1002,
            1010,
            1011,
            1012,
            1020,
            1021,
            1022,
            1120,
            1121,
            1122,
            1210,
            1211,
            1212);
            
my @get_list   = (
            '100',
            '200',
            '210',
            '220',
            '230',
            '240',
            '1000',
            '1001',
            '1002',
            '1120',
            '1210',);

my $lc = List::Compare->new(\@dead_list, \@get_list);
my @result = $lc->get_unique;

say Dumper(@result);

__END__
@result = (
            '101',
            '1010',
            '1011',
            '1012',
            '1020',
            '1021',
            '1022',
            '103',
            '1121',
            '1122',
            '1211',
            '1212',
            '201',
            '202',
            '203',
            '211',
            '212',
            '221',
            '222',
            '231',
            '232',
            '233',
            '241',
            '242',
            '243'
          );

[download]

Cheers,

Brent

-- Yeah, I'm a Delt.

In reply to Re: Array lookup by dorko
in thread Array lookup by bartrad

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