Spring 2019 CS231
This is a course about algorithms; their design and analysis
The language of computer science is to a great extent the language of algorithms. Although there are many thousands of algorithms, there are relative few basic design techniques. These include: divide-and-conquer, greedy, dynamic programming, and network flow. We will illustrate these techniques by studying a few fundamental algorithms of each type. In addition to helping us understand classic solution techniques, these algorithms have proven very useful in practice. Their names and the names of the problems they solve have become a standard part of the language of computer science.
Unfortunately, there is rarely a best algorithm to solve a given problem. Each approach involves a series of tradeoffs. Therefore, we will also study methods for evaluating the usefulness of an algorithm in a given situation. Among the various competing measures, we will focus primarily on the anal- ysis of time and space complexity. However, a number of other issues will also be discussed.
Part I - Basics
Lecture 2: Stable Matching Problem
Lecture 3: Stable Matching Problem
Sections 1.1 and 2.3
Part II - Graphs
Lecture 5: Intro and Representation
Sections 3.1 and 3.2
Lecture 7: Directed Graphs
Sections 3.5 and 3.6
No class (snow day)
Lecture 10: Interval Scheduling
Section 4.1 and 4.2
Part IV - Divide and Conquer
Lecture 14: Mergesort and Counting Inversions
Section 5.1 and 5.2
Part V - Dynamic Programming
Lecture 16: Basics and Principles
Sections 6.1 and 6.2
Lecture 20: Network Flow and Computational intractability
Sections 8.1 and 8.3
Prerequisites The prerequisite for CS231 is CS230, and Math 225. Students with significant mathematical experience (writing and understanding proofs), or those who have not taken Math 225 need the permission of the instructor.
Textbook - Very Important!! The textbook for this semester is Regular readings will be assigned from the required text, Algorithm Design, by by Jon Kleinberg and Eva Tardos, 1st edition. It is required that you read the relevant sections every lecture.
The Google Group is CS-231-01-SP19. You should make sure that you are subscribed to this group. Important course announcements will be posted to the group, such as corrections to assignments and clarifications of material discussed in class.
Lectures There are two 75-minute lectures each week that will introduce the main content of the course. Lectures are held on Mondays and Thursdays at 9:55-11:10 AM in SCI 364.
Discussion Sections Similar to Supplemental Instruction (SI), discussion sections is a support program offered for selected Wellesley courses. Our discussion leaders are trained and highly experienced in tutoring. They will offer multiple study sections each week throughout the semester. During discussion sections, they will cover problem set solutions and review important concepts. Discussion sections are open to all students enrolled in the course. We highly recommend attending at least one of these sections every week, as well as reviewing the handouts used in them.
Final Presentations and Paper: During the last few weeks of the semester, teams of 3 students work on a short survey paper. After choosing an interesting algorithmic problem, you will first read related literature on the topic, and summarize your findings into a short scientific paper (5 pages). Each team will present their work in a final presentation during the last two classes, and will prepare a short paper to be submitted by the last day of exams.
Exams: There will be three in-term, non-collaborative exams that are open book and open notes. There will be no final exam, as there will be a final presentation and paper instead. The dates of the exams are listed on the schedule. Please mark the exam dates in your calendars as they are not flexible.
Final Grades Your final grade for the course will be computed as a weighted average of several components. The relative weight of each component is shown below:
You are encouraged to talk with CS231 team members and classmates about the course and to form study groups. Unless otherwise instructed, feel free to discuss problem sets with classmates and exchange ideas about how to solve them.
You are encouraged to work in teams with other students. The team members can work together closely but each student must write and submit their own solution. You must mention the names of your collaborator(s) in your assignment.
While open exchange of ideas is encouraged, there is a thin line between collaboration and plagiarism. Please note that you must compose your own solution to each assignment. Furthermore, you should never look at another student's solutions. For example, it is OK to borrow ideas from the textbook, from materials discussed in class, and from other sources as long as you give proper credit. However it is unacceptable and constitutes a violation of the Honor Code (1) to write a solution together and turn in two copies of the same solution, (2) to copy a solution written by your classmates, (3) to read another student's or team's solution or (4) to view assignments, exams and solutions from previous terms of CS231.
In keeping with the standards of the scientific community, you must give credit where credit is due. If you use an idea that was developed by (or jointly with) others, please reference them in your work. It is unacceptable for students to work together but not to acknowledge each other in their write-ups.