if ($in{username} =~ /^(\[a-zA-Z]{2})/ || ' ') {
     $dirtype = $1 || 'other';
}

##</code><code>##

my $dirtype;
if ( $in{username} =~ /^([a-zA-Z]{2})$/ ) {
     $dirtype = $1;
} else {
      $dirtype = 'other';
}