CS61A_sp07_mt2 - CS 61A, Spring 2007, Midterm 2, Harvey...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
CS 61A, Spring 2007, Midterm 2, Harvey Question 1 (6 points): What will Scheme print in response to the following expressions? If an expression produces an error message, you may just write “error”; you don’t have to provide the exact text of the message. Also, draw a box and pointer diagram for the value produced by each expression. (map car ‘((cons 1 2) (list 3 4))) (let (( x (list 1 2)) (y (list 7 8))) (cons x (list y x))) (list (append ‘(a b) ‘(c)) (cons ‘(a b) ‘(c)))
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Question 2 (5 points): We’re going to represent a date as simply a list of three numbers (define (make-date year month day) (list year month day)) (a) Write selectors for year, month, and date. Given a date, they should return the appropriate value. (define (year date) ___________________________) (define (month date) ___________________________) (define (day date) ___________________________) (b) Now, we’re going to use those dates to represent events. An event has a start date, an end date, and a description in the form of a sentence. Given the following selectors for an event, write a constructor for an event.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 7

CS61A_sp07_mt2 - CS 61A, Spring 2007, Midterm 2, Harvey...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online