ADMIN: QOTW #9 becomes QOTF

There was very little discussion of either of quizzes #9 on the
-discuss list this week (although the few solutions that were posted
looked quite good) so I've decided to extend the quiz duration for
another week to see if anyone has time to work on it over the
holidays.  I'll post a report about it around December 30.

After that I'll go on vacation for a week, so quiz #10 will go out on
Wednesday, January 8.

Finally, I have not forgotten the postmortem of expert quiz #8.
Here's what happened: I started writing it, and then got really
interested in it, and started working on a really cool dynamic
programming solution that should be super-fast.  But then I realized
that I wasn't working on my book, and chapter VI is imminently due.
So I put it aside for a while.  I will get back to it before the year
is out.

Happy new year to everyone!