my @union = my @isect = my @diff = ();
my %union = my %isect = ();
my %count = ();
my $e;

foreach $e (@erg1, @erg2)
{
	$count{$e}++
}

foreach $e(sort(keys %count))
{
	push(@union, $e);
	
	if ($count{$e} == 2)
	{
		push @isect, $e;
	}
	else
	{
		push @diff, $e;
	}
}

$listbox_right->insert('end', @diff);