#!/bin/perl
my @array = qw(1 2 3 4 5 6 7 8 9 10 11 12);

my $counter = 1;
my $data;

for my $pos (0 .. $#array) {

        print $array[$pos],"\n";
        push @{$data->{$counter}}, $array[$pos];
        if ($counter == 4) {
                $counter = 1;
        } else {
                $counter++;
        }

};

use Data::Dumper;
print Dumper($data);