CSC 151.01, Class 19: Recursion with helper procedures

Overview

• Preliminaries
  • Notes and news
  • Upcoming work
  • Extra credit
  • Questions
  • PSA
• Quiz
• Lab
• Debrief

News / Etc.

• New partners.
• Please make sure to return your computer cards to the jar.
• I plan to have all grades back on Monday. (Except for Exam 2, of course.)
• I’ve been answering questions on exam 2 and you should see many updates in the Q&A section.

Upcoming Work

• Writeup for class 18 due Friday at 10:30 p.m.
  • Exercise 7
  • To: csc151-01-grader@grinnell.edu
  • Subject: CSC 151.01 Writeup 18 (YOUR NAMES)
• NO WRITEUP FOR CLASS 19.
• Reading for Monday’s class: List recursion, revisited
• Exam 2 prologue due TONIGHT at 10:30 p.m.
• Exam 2 due Tuesday at 10:30 p.m..
• Exam 2 cover sheets due Wednesday at the start of class
• Exam 2 epilogue due Wednesday at 10:30 p.m.

Extra credit (Academic/Artistic)

• TODAY, 4:15 pm, Poet talk
• Nice Fish this weekend
• “Sita Sings the Blues,” at 3:30pm on October 8 in the Gallery

Extra credit (Peer)

• Volleyball vs. Beloit, TONIGHT at 7:00 p.m. FREE T SHIRTS
• Women’s Tennis vs. St. Norbert, Saturday at 9:00 a.m. (Field house or High school?)
• Volleyball vs. Lake Forest, Saturday at 1:00 p.m.
• Women’s Tennis vs. Ripon, Saturday at 3:00 p.m.
• Nice Fish. This weekend. Marvel at the lights.

Extra credit (Misc)

• Any Field Day (aka “This is not 10/10”) event

Other good things

• Football, Saturday at 1:00 p.m.
• Neverland Players, this weekend.
• Lunar new year celebration tonight (Sam lost his notes, thinks 6:20 p.m. in Harris gym with FREE FOOD and AWESOME PERFORMANCES)

Questions

On problem 1, do we have to handle the case in which the start is larger than the end?

No, provided you make an appropriate precondition.

PSA

• Stay well.

Quiz

Lab

Please discuss which switching format you and your partner will use

• Switch every ten minutes
• Switch midway through class
• Switch every problem

Whoops! Typos in code in lab. Sorry!

> (my-quotient (list 5))
5
> (my-quotient (list 5 3))
5/3 ; or 1 2/3
> (my-quotient (list 5 3 7))
5/21
> (my-quotient (list 5 3 7 5))
1/21
> (my-quotient (list 5 3 7 5 1/3))
1/7

NO WRITEUP

Debrief

We will do the debrief at the beginning of the next class.