#!/usr/bin/perl
use strict;use warnings;
	my $num =3;
	$"=',';print join "\n",glob join "_",("{@{ [1..12] }}")x$num;
___END___
1_1_1
1_1_2
1_1_3
1_1_4
1_1_5
1_1_6
...
12_12_7
12_12_8
12_12_9
12_12_10
12_12_11
12_12_12