#!/usr/bin/env perl

use 5.010;
use strict;
use warnings;

say for glob '{' . join('}-{' => map { join ',' => split } <DATA>) . '}';

__DATA__
1 2
3 4 5
6 7
8 9

##</code><code>##

$ pm_2d_comb.pl
1-3-6-8
1-3-6-9
1-3-7-8
1-3-7-9
1-4-6-8
1-4-6-9
1-4-7-8
1-4-7-9
1-5-6-8
1-5-6-9
1-5-7-8
1-5-7-9
2-3-6-8
2-3-6-9
2-3-7-8
2-3-7-9
2-4-6-8
2-4-6-9
2-4-7-8
2-4-7-9
2-5-6-8
2-5-6-9
2-5-7-8
2-5-7-9