33rpm.pl

#!/usr/bin/perl

use strict;
use warnings;

my $example = [1, '', 3, 4, '', ''];

sub func {
    my ($example, $value) = @_;
    my $ret;
    while (!$ret) {
        $value = ($value + 1) % @$example;
        $ret = $example->[$value-1];
    }
    return $ret;
}

for (1..6) {
    print func($example, $_),"\n";
}