#!/usr/bin/perl

use strict;
use warnings;

{
 local ($,,$\) = (" - ","\n");
 while (<DATA>) {
  chomp; print split(/-/) for split(/,/)
 }
}

__DATA__
1-2,3-4,2-5
2-1,2-5
3-5,1-9,2-2,4-8