Tyler Zhu Blog and Personal Website computer science, mathematics, rationality, and machine learning.
This semester, I am a TA for CS 70 with Professors Babak Ayazifar and Anant Sahai.
My discussion sections are Wednesdays and Fridays 2-3PM in Dwinelle 105, and my office hours are on Fridays 4-5PM in Soda Alcove 347.

Discussion Notes

For every discussion, I've created recap sheets which serve as short summaries of the most important topics being discussed, as well as some tips that I've gathered which are useful to know. Students in the past have told me they would find such a resource useful, so this is my attempt at fulfilling that need. My philosophy is to think of them as takeaways or the main ideas behind the notes/discussions; they can't replace the act of working through the notes or discussion problems, but they're useful to read before and/or after to understand the big concepts. For more sheets of the same flavor, check out Alvin Wan's crib sheets. I'll try to update these by EOD of each discussion, although currently I'm lagging behind (beer-virus is to blame).
  • January 22nd: Discussion 0A, Sets and Propositional Logic.
  • January 24th: Discussion 0B, Proofs.
  • January 29th: Discussion 1A, Induction.
  • January 31st: Discussion 1B, Stable Matching.
  • February 5th: Discussion 2A, More Stable Matching (see 1B).
  • February 7th: Discussion 2B, Graph Theory.
  • February 12th: Discussion 3A, Modular Arithmetic.
  • February 14th: Discussion 3B, Fermat's Little Theorem, Bijections, and the Chinese Remainder Theorem.
  • February 19th: Discussion 4A, RSA.
  • February 21st: Discussion 4B, Polynomials and Secret Sharing.
  • February 26th: Discussion 5A, Secret Sharing and Error Correcting Codes.
  • February 28th: Discussion 5B, Error Correcting Codes and Berlekamp-Welch.
  • March 4th: Discussion 6A, Counting I.
  • March 6th: Discussion 6B, Counting II (Balls and Boxes, see below handout).
  • March 11th: Discussion 7A, Countability and Computability (no longer in-scope).
  • March 13th: Discussion 7B, Intro to Discrete Probability.
  • March 18th: Discussion 8A, Conditional Probability.
  • March 20th: Discussion 8B, Inclusion-Exclusion Principle and the Union Bound.
  • April 1st: Discussion 9A, Discrete Probability Distributions.
  • April 3rd: Discussion 9B, Linearity of Expectation and Random Indicator Variables.


Here are some handouts I've written on various CS 70 topics.
  • Discussion 0A Slides: My slides discussing an overview of CS 70 and detailing some useful resources.
  • Lagrange Interpolation: A step by step derivation of Lagrange Interpolation.
  • Balls and Boxes: A short, detailed note on the ways to use the Balls and Boxes counting method as well as its different applications.


Let me know how I'm doing! Feel free to give anonymous feedback here.