simple.pl

simple.pl

# http://twitter.com/ditto572/status/264921423112458240
#
# perl -MBytes::Random::Secure=random_bytes_base64 -E 'print random_bytes_base64(32) for ( 0 .. 120000)' > list 
# perl -MBytes::Random::Secure=random_bytes_base64 -E 'print random_bytes_base64(32) for ( 0 .. 50000)' > list2

use strict;
use warnings;

my %h;
{
    open my $fh, '<', 'list1' or die;
    $h{$_}++ while (<$fh>);
    close($fh);
}
{
    open my $fh, '<', 'list2' or die;
    while (<$fh>) {
        print unless exists $h{$_};
    }
    close($fh);
}

real 0m0.610s
user 0m0.246s
sys 0m0.113s