A student asks:

        Dr. Patt,
        In today's lecture you mentioned that we were not going
        to cover the residue number system. However the last
        question in Problem Set 5 is asking about the residue
        number system. Are we expected to know that for the exam?
        Or maybe I was out to lunch and did not hear you correctly.
        If so please forgive the dumb question.
        <<name withheld to protect the ...>>

Ooops.  I thought we took the residue number question off the problem set.
Yes, you will not see anything about residue numbers on the midterm next
Monday.  ...and nothing about carry lookahead, ...and nothing about Booth's
I had not planned to cover residue numbers (because it is a little esoteric)
or carry lookahead (because I figured you had it in 316) today.  But, I did
expect to cover Booth's algorithm.  So much for those plans.
Anyway, after class, two students came up to tell me that carry lookahead is
not covered in 316.  ...which means I better cover it right after the exam,
since I really do not want you to graduate without understanding carry
lookahead.  One of the graduate students, impressed with the mathematical
beauty and elegance of residue numbers, felt that it too should be covered.
Guess we really do need to continue classes right through Christmas.  I will
check with the Dean.  If the Dean does not allow me to hold classes through
Christmas, I think I will pass on residue numbers.  I will, in any case, explain
carry lookahead and Booth's algorithm on the 21st.
Good luck on the 2nd midterm.  See you in class on the 21st.
Yale Patt