Code snippets for the HackRec SICP Class
Scheme Racket Emacs Lisp
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Previous class notes (often updated after class with more detail on the exercises).
Scheme files from our class discussions.
Scheme files from various student’s work. I’ve put my own homework responses in there as well.

Intermission and Review

Simply Scheme

15 SICP 2.2.2

Section 2.2.2

Exercise 2.24

We discussed this in class #14, and there are some notes in 14.scm. We’ll start with it again, though. Try tracing through a couple of lists by writing out the cons cells. If you can see a sublist, it’s in the car of cell.

Exercise 2.25

Exercise 2.26

Exercise 2.27

Think recursive!

Exercise 2.28

This will be pretty similar to the last exercise.

Exercise 2.29

Exercise 2.30

Exercise 2.31

Exercise 2.32


See The Schedule for old classes and notes on the exercises.

SICP Solutions

A couple of comments/propaganda about CS61A (you don’t need to read these):