Efficient Algorithms and Intractable Problems

Fall 2011

Announcements People Sections Homeworks Exams Notes and Text Grades


  • (12/13) The final exam will be in 105 Stanley Hall, on Dec 14 from 8-11am.
  • (12/5) For a description of how Dr. Seuss deals with Halting Problem, click here
  • (12/5) Prof. Demmel has jury duty today (and possibly longer). So his office hours are cancelled until further notice.
  • (10/31) Starting today, Prof. Demmel's Monday office hours will be 2-3pm.
  • (10/21) Tobias Welp has changed his office hours: He will now hold office hours Thursdays 4-5pm in 611 Soda, instead of on Mondays (his Wednesday office hours remain unchanged).
  • (10/2) You do not need to bring blue books to exams.
  • (9/19) We have posted pointers to various on-line notes about Big-Oh, below at the end of Notes and Text
  • (8/30) Several people have asked whether the homework in the on-line version of the book is identical to the printed version in the bookstore: They are not entirely consistent, so please refer to the printed version.
  • (8/26) We have decided to use Piazza as our tool for on-line questions and answers instead of newsgroups. The webpage has instructions for creating an account if you do not already have one; please send questions to Tobias.

  • (8/25) Welcome to CS170!

  • People and contact information

    Lecturer: Professor James Demmel - email to demmel@cs

    Office: 564 Soda, 643-5386; also 831 Evans
    Lectures: TTh 11:00-12:30 (100 Lewis)
    Office hours: M 2-3 (changed starting 10/31), T 2-3 and F 2-3 in 564 Soda (or in a nearby meeting room), or by appointment


  • Tobias Welp (Head GSI) - email to twelp@eecs
    Office hours W 4-5 in 651 Soda, and Th 4-5 in 611 Soda
  • Siu Man Chan - email to siuman@cs
    Office hours TW 3-4 in 751 Soda
  • Hoa Long Tam - email to hoalong.tam@berkeley
    Office hours M 11-12 and T 1-2 in 651 Soda
  • Thomas Watson - email to tom@cs
    Office hours WF 10:30-11:30 in 611 Soda
  • Please send questions about homework to all 5 instructors (professor and GSIs) by using Piazza. The webpage has instructions for creating an account if you do not already have one; please send questions about creating a Pizza account to Tobias. For questions about enrollment and other personal questions, please send email to cs170@inst.eecs.berkeley.edu.

    Discussion Sections

  • Sec 101: Th 2-3, 6 Evans (Hoa)
  • Sec 102: Th 3-4, 71 Evans (Thomas)
  • Sec 103: Th 4-5, 6 Evans (Siuman)
  • Sec 104: Th 2-3, 103 Moffitt (Siuman)
  • Sec 105: F 11-12, 3102 Etcheverry (Hoa)
  • Sec 106: F 1-2, 3105 Etcheverry (Thomas)
  • Sec 107: Th 5-6, 70 Evans (Tobias)
  • Enrollment: Please send all queries to Michael-David Sasson or Head GSI Tobias Welp


    Please send questions about homework to all instructors by using Piazza. (For enrollment or other personal questions please email cs170@inst.eecs.berkeley.edu.)

    The (roughly weekly) homework sets (and solutions) will be posted here as the term progresses.

    In general, problem sets will be assigned on Wednesday and will be due Friday the following week at 4pm in the boxes in 283 Soda Hall. Make sure to put your name, SID, course name (CS170), homework number, TA's name, and section number on the first page, and staple all the pages together.

    For homework questions that involve designing and analyzing algorithms, we require a specific format for the answers (to both help you organize your thoughts and help the readers grade your answers), that you can find here.

    You are encouraged to work on homework problems in study groups of 2 to 4 people. But you must write up your own solutions, and not read or copy the solutions of other students. You may use books or on-line resources to help solve homework problems, but you must credit all such sources in your writeup and you must not copy material verbatim. See also the discussion of grading and academic honesty below. We believe that most students can distinguish between helping other students and cheating. Explaining the meaning of a question, discussing a way of approaching a solution, or collaboratively exploring how to solve a problem within your group is an interaction that we encourage. On the other hand, you should never read another student's solution or partial solution, nor have it in your possession, either electronically or on paper. You must never share your written solutions, or a partial solutions, with another student, even with the explicit understanding that it will not be copied. You should write your homework solution strictly by yourself. You must explicitly acknowledge everyone who you have worked with or who has given you any significant ideas about the homework. Not only is this good scholarly conduct, it also protects you from accusations of theft of your colleagues' ideas.

    Warning: Your attention is drawn to the Department's Policy on Academic Dishonesty. In particular, you should be aware that copying or sharing solutions, in whole or in part, from other students in the class or any other source without acknowledgment constitutes cheating. Any student found to be cheating risks automatically failing the class and being referred to the Office of Student Conduct.

    No late homework will be accepted, since the answers will be posted on the web immediately afterwards. Instead, the lowest 3 homework scores will be dropped.

    Note that the homework in the printed version of the book is not completely consistent with the on-line version of the book, so please refer to the printed version of the book.

  • Homework 1 (in pdf), due Sep 2
  • Homework 2 (in pdf), due Sep 9
  • Homework 3 (in pdf), due Sep 16
  • Homework 4 (in pdf), due Sep 23
  • Homework 5 (in pdf), due Sep 30
  • Homework 6 (in pdf), due Oct 7
  • Homework 7 (in pdf), due Oct 14
  • Homework 8 (in pdf), due Oct 21
  • Homework 9 (in pdf), due Oct 28
  • Homework 10 (in pdf), due Nov 4
  • Homework 11 (in pdf), due Nov 14 (Note: the due date is delayed because Nov 11 is a holiday. Homework 12 will be due Nov 18 as usual.)
  • Homework 12 (in pdf), due Nov 18
  • Homework 13 (in pdf), due Nov 28

  • Exams and Quizzes

  • There will be a short, closed-book quiz at the beginning of each discussion section.
  • The rules for the exams are as follows: Closed book, closed calculator, closed computer, closed network, and open brain. You are permitted a 1 page, double-sided set of notes, large enough to read without a magnifying glass.
  • The final is Wednesday, December 14, 8-11am.
  • Midterm 1 will be in class on Tuesday, Oct 4.
  • Midterm 2 will be in class on Tuesday, Nov 1.
  • Sample midterms and finals from earlier semesters are available here
  • The final exam will be in 105 Stanley Hall.

  • Notes and Text

    The required textbook for the course is Algorithms, by Dasgupta, Papadimitriou and Vazirani.

    It was developed from a set of notes especially for this course, and we will follow it fairly closely. The previous text book was Introduction to Algorithms by Cormen, Leiserson and Rivest, which is still a good reference.

    Prerequisites: The prerequisites for this course are CS 61B, and either CS 70 or Math 55. In particular you should be comfortable with mathematical induction, big-O notation, and basic data structures. If you need to refresh any of this material, refer to the relevant sections of the textbook. We assume that you are familiar with a standard imperative programming language like C, C++ or Java, so that you can read and write the algorithms presented in the course.

    Before this textbook became available, I posted very detailed lecture notes for each lecture on this web page. The availability of this textbook means the notes will mostly point to the sections of the book covered, but I will continue to post more detailed notes of material not in the book.

    Tentative schedule and Lecture Notes

    Pointers to on-line notes on Big-Oh, for those wishing review:
  • Lecture notes from CS 61A (various versions of the class): lecture 4, lecture 6, reader, starting at p. 280; same as in V2 of course reader
  • Section notes from MIT's version of 61B: 6.006
  • Shewchuk's notes on Big-O: lecture 20, lecture 21
  • Hilfinger lecture slides on Big-O: lecture 15
  • Lecture slides from Stanford's version of 61B: lecture 14, Video of that lecture
  • Video lecture from IIT Bombay's version of 170
  • Video lecture from MIT's version of 170

  • Grades

    Grades will be based on homework, quizzes, 2 midterms and a final:

    The final exam is scheduled for Dec 14, 8-11am. A makeup final will only be given for

    1. unexpected circumstances beyond your control, documented by a signed note from a physician or equivalent,
    2. a religious holiday, or
    3. conflict with another scheduled exam (ask the other professor first, and try to avoid this!!).
    There will be no makeup midterms. Instead, each midterm score will be replaced by the maximum of your midterm score and your score on the final (whether you take the midterm or not).

    You are required to a bring a student photo ID to the exams.

    There will be a short quiz at the beginning of (most) sections. The quiz will consist of a few simple questions related to the material from the previous class. There will be no make-up quizzes but the two lowest quiz scores will be dropped. The motivation is to encourage you to keep up with lectures.

    Regrading of homework, quizzes or exams will be done when there has been a mistake, in order to make sure all students are graded consistently. To ask for a regrade, you must return the work to your TA within one week of getting it back, along with a written note (on another piece of paper) explaining the problem. The entire assignment may be regraded in this case.