my @sets = sort(keys(%HoHoA));

while(@sets)
  {
  my $set1 = shift(@sets);

  foreach my $part1 (sort(keys(%{$HoHoA{$set1}})))
    {
    #note that the earlier shift has already taken off
    #the part we don't want to match against
    foreach my $set2 (@sets)
      {
      foreach my $part2 (sort(keys(%{$HoHoA{$set2}})))
        { print "$part1 - $part2\n"; }
      }
    }
  }