Times listed are in EST. Assignments are released on Thursday mornings, and are due 11:59pm on Wednesdays. Clicking on the Overleaf Template link will open a new Overleaf project, so you can write your homework solutions in LaTeX.

How do hours work?

CS22 hours are collaborative spaces for students to work together on problems, facilitated by TAs. Hours will be primarily in-person. More details about hours can be found in the Hours and Recitation Policy. Remote hours will be facilitated using tickets handled from Hours.

Here is a link to the course calendar (same as below).

Course Textbook

Discrete Mathematics and Its Applications — Kenneth Rosen

Reading this textbook is not required, though many students in the past have found it helpful in reinforcing what's covered in lecture!

Course Documentation

• Course Missive
• Collaboration Policy
• Hours and Recitation Policy

Important Links

• EdStem
• Gradescope
• Anonymous Feedback Form
• Extension Request Form
• Recitation Absence Form
• Lecture Recordings/Livestream

Homework Resources

For many of you, this is your first time writing proofs, and even for those who have written proofs before, what we consider a good proof in CS22 likely differs from what made a good proof wherever you were writing them before! Check out the proof virtues document below to acquaint yourself with what we consider a good proof in CS22. Your proofs will be graded with respect to this document , so be sure to read it carefully, and come to hours with any questions.

• Proof Virtues

Lean Resources

• Lean Github
• Class Lean Documentation

Math Resources

• What don't I have to prove?
• Set Identities
• Logical Equivalences

Sample Proofs

• Bidirectional
• Bijective Proof Sketch
• More Bijective Proof Sketches
• Bijective Strategies
• Cases
• Contradiction
• Contraposition
• Counterexample
• Equivalence Relations
• Induction
• More Induction
• Strong Induction
• Probability
• Set Equivalence

The LaTeX files to all the above resources can be found here.

LaTeX Resources

LaTeX (pronounced la-tek) is a program that you will be using to make your homework solutions look beautiful. The sample proofs above were written in LaTeX to give you an idea of what documents written in LaTeX look like. LaTeX allows you to incorporate mathematical notation into your proofs, and because this class involves a healthy dose of mathematical notation, LaTeX is going to be very useful! Using LaTeX is required after the 2nd homework.

We don't expect you've ever done this whole LaTeX business before, and that's why we're giving you some time to learn it! To get started, we recommend creating an account on Overleaf, an online program for writing and compiling LaTeX. After you do that, here are some links to check out: Honestly, please use Overleaf. It's so much easier than installing anything on your computer. Trust me.

• CS22 LaTeX Cheat Sheet (start here!)
• A Not So Short Introduction to LaTeX
• LaTeX Symbols Guide
• Art of Problem Solving: LaTeX
• LaTeX Intro Wikibook
• LaTeX on Brown CS Systems
• LaTeX Gearup Template
• LaTeX Gearup Completed Handout

In general, a really good resource for learning LaTeX is the web. When you have a question, google it, and you'll likely find someone who had the very same question!

If you'd like to download LaTeX on your computer, here are some resources to do that:

• MiKTeX (Windows)
• MacTeX (Mac)
• Texmaker (Cross Platform)

If you're using LaTeX and you just don't know what the code for some symbol is, here is a helpful list to start:

Common LaTeX symbols

Alternatively, this is a neat site which will return the LaTeX code based on handwritten input (although searching your question on the web is likely more efficient):

DeTeXify

Midterm Exam Resources

The midterm practice exam is not a substitute for studying the homeworks, recitations, and lectures!

Practice Midterm

Practice Midterm with Solutions

The Midterm Reference Sheet is what you will have during the actual exam as a "cheat sheet".

Created by the TAs, the Midterm Review Guide is a study guide for the exam. There is no solution key for the practice problems, but we are happy to help!

Contact

• cs0220headtas@lists.brown.edu
• cs0220tas@lists.brown.edu
• cs220-instructors@brown.edu