100% satisfaction guarantee Immediately available after payment Both online and in PDF No strings attached
logo-home
Previously searched by you
Previously searched by you
logo
Problem Set 7 - UBC 2024 - CPSC 110 CA$8.68   Add to cart
Quickly navigate to
Preview
  2.  
  3. University Of British Columbia (UBC )
  4.  
  5. Computer Science
  6.  
  7. CPSC 110

Class notes

Problem Set 7 - UBC 2024 - CPSC 110
 105 views  1 purchase

Completed file for problem set 11. Remember to copy the pdf file to Dr Racket for a better view. This file should be exactly identical except that the file has answers for each problems.

Preview 2 out of 12  pages

Document information

  • December 20, 2022
  • 12
  • 2022/2023
  • Class notes
  • Gregor kiczales
  • All classes

Subjects

Written for

All documents for this subject (19)

Seller

avatar-seller
tranghane

Reviews received

Content preview

;; DO NOT PUT ANYTHING PERSONALLY IDENTIFYING BEYOND YOUR
CWL IN THIS FILE.
;; YOUR CWLs WILL BE SUFFICIENT TO IDENTIFY YOU AND, IF YOU HAVE
ONE, YOUR
;; PARTNER.
;;
(require spd/tags)

(@assignment psets/pset-07); Do not edit or remove this tag

;; If you are:
;; - A 110 or 107 student replace the first set of '???'s with your cwl.
;; For problem sets, If you have a partner, please replace the second
;; set of '???'s with their cwl. Remember this, it is what you will
;; do with these @cwl annotations for the whole course.
;; - A UBC Extended Learning student, replace the first set of ??? with
;; your email address as confirmed in the email you received from
;; extended learning. The handin password is also in that email.
;; Remember this, it is what you will do with these @cwl annotations
;; for the whole course.
;;
(@cwl ??? ???)

(@problem 1)

(@htdd 1String)
;; 1String is String
;; interp. a 1String represents a single letter
;; CONSTRAINT: any 1String is only one letter long

(@htdd ListOf1String)
;; ListOf1String is one of:
;; - empty
;; - (cons 1String ListOf1String)
;; interp. a sequence of letters

(define L1 empty)
(define L2 (list "a" "B" "c"))

(@htdd Operations)
;; Operations is one of:

, ;; - empty
;; - (cons "keep" Operations)
;; - (cons "space" Operations)
;; - (cons "remove" Operations)
;; interp. a sequence of operations to apply to a list of 1String
;; "keep" means keep the corresponding letter
;; "space" means replace the corresponding letter with a " "
;; "remove" means remove the corresponding letter

;;
;; In this problem you will design a function called decoder, that will
;; decode encrypted messages! Very poorly encrypted messages. The function
;; consumes a ListOf1String (l) and Operations (ops) in that order. The
;; function should produce a String which is the result of applying the
;; given operations to the successive 1String and joining the resulting
;; letters together.
;;
;; For example:
;; (decoder (list "i" "k" "l" "h" "a" "m" "k" "s" "a" "r" "m")
;; (list "keep" "remove" "remove" "space" "keep" "keep"
;; "space" "keep" "keep" "remove"))
;;
;; should produce "i am sam"
;;
;; Notice that some of the letters were kept, some were replaced with a space,
;; and some were removed.
;;
;; If ops runs out of operations before the end of the 1String, then all
;; the remaining letters in l are kept.
;;
;; If l runs out of 1String first, then the remaining operations in ops are
;; ignored.
;;
;; Example 2:
;; (decoder (list "f" "a" "d" "e")
;; (list "remove" "keep" "space" "keep" "remove" "keep" "space"))
;;
;; should produce "a e"
;;

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller tranghane. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for CA$8.68. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

60904 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 14 years now

Start selling
CA$8.68  1x  sold
  • (0)
  Add to cart