CSC151.01 2015F, Class 25: Recursion Basics, Continued
======================================================

_Overview_

* Preliminaries.
    * Admin.
    * Upcoming Work.
    * Extra Credit.
    * Questions.
* Quiz.
* Lab.

Preliminaries
-------------

### Admin

* Continue partners
* Don't forget to take a random number for your exam!  (I'll bring more
  later today if we run out.)
* Thank you to all the folks who show up for review sessions.  It's one of
  my favorite teaching experiences each week.  I really enjoy the challenge
  of having to ad-lib answers to unexpected questions.
* Notes on HW 5 to be distributed some time soon
* How many of you would show up to a Monday-night review session with a mentor?
    * If it did not include discussion of the current homework?
    * If it did include discussion of the current homework?
* I will offer our optional final at the two times allocated to this course: 
  9am Tuesday 15 December 2015 or 2pm Tuesday 15 December 2015.  (At most 
  one time is necessary.)
* Friday PSA.

### Upcoming Work

* Reading for Monday:
  [Verifying Preconditions](../readings/preconditions-reading.html) 
* [Exam 2](../assignments/exam.02.html)  
    * Prologue due TONIGHT!
    * Exam due in electronic form Tuesday night
    * Exam due in hardcopy Wednesday class time
    * Epilogue due Wednesday night
* Today's Lab writeup (due before class Tuesday)
    * Email to <grader-151-01@cs.grinnell.edu> 
    * Subject: _CSC 151 Lab Writeup Class 25 (Your Names)_
    * Exercises: 4 and 5

### Extra Credit Opportunities

* If possible, send me these in advance.

#### Academic

* Any visit to the current show in the Faulconer gallery
* Sarah Purcell and Jim Eimborg on The Digital Liberal Arts and You,
  Friday, 4:15 pm, ARH 102
* CS Table Tuesday, noon, White Dining Room (C)

#### Peer Support

* Pals of PALS, pals@grinnell.edu, normally Saturday at 7:45 am (breakfast
  included), Sunday at 4:45, and Mondays at 4:45.  Requires sign up in 
  advance.  
* Pun Club, Saturdays, 4pm, Way over Younker.
* Socrates Cafe', 2pm on Saturday 2nd Younker
* Study Abroad Session, Monday the 12th 7-8pm in JRC 101.  Hear about 
  Study Abroad Experiences and think about Study Abroad.
* The Boy who Fell From The Roof.  Tonight.  Tomorrow Night.  Sunday 
  afternoon. (EG helped build the set)

#### Miscellaneous

* HPMOR Discussion Group Saturday at 3pm <http://hpmor.com/chapter/1>;
  [wuruth17] (now postponed until after break :-(

### Other Good Things

* Friends of Drake Library book sale this weekend.
  Friday 5-8 pm.  Saturday 8am-2pm.  Admission $3 on Friday and $0 
  on Saturday.
* Women's soccer noon on Saturday.
* Men's soccer 2:30 p.m. on Saturday.

### Questions

* Where is EG?  Off at a literature conference.  We miss you!

Quiz
----

EG says that I should apologize to you for a seriously evil quiz.
But I have confidence in you.  If it does turn out to be as evil as she
suggests, I will probably work something out (e.g., weight whichever part
you did better on higher or be more lenient in grading).

Lab
---

Writeup: Exercises 4 and 5 

Exercise 3 on the lab should feel familiar.  Try doing it without referring
back to your notes on it from Wednesday.

The Extras on this lab will be particularly helpful as you get ready for
future work on recursion.

For exercise 4, you might find the following philosophical Scheme statements
useful

        > (+)
        0
        > (*)
        1
