my @old = split(/\s+/, $old);
	my @new = split(/\s+/, $new);

	traverse_sequences(\@old, \@new, 
	{
  	 MATCH => sub { print OUTPUT shift(@old)."\n"},
  	 DISCARD_A => sub { print OUTPUT "<strong><font color=red>".@old->[shift]."</font></strong>\n"},
   	 DISCARD_B => sub { print "<strong><font color=blue>".@new->[shift, shift]."</font></strong>\n"},
	}
	);