all-notes - Algorithms Department of Computer Science...

Algorithms
Department of Computer Science
University of Illinois at Urbana-Champaign
Instructor: Jeff Erickson
Teaching Assistants:
• Spring 1999: Mitch Harris and Shripad Thite
• Summer 1999 (IMCS): Mitch Harris
• Summer 2000 (IMCS): Mitch Harris
• Fall 2000: Chris Neihengen, Ekta Manaktala, and Nick Hurlburt
• Spring 2001: Brian Ensink, Chris Neihengen, and Nick Hurlburt
• Summer 2001 (I2CS): Asha Seetharam and Dan Bullok
• Fall 2002: Erin Wolf, Gio Kao, Kevin Small, Michael Bond, Rishi Talreja, Rob McCann, and
Yasutaka Furakawa
• Spring 2004: Dan Cranston, Johnathon Fischer, Kevin Milans, and Lan Chen
• Fall 2005: Erin Chambers, Igor Gammer, and Aditya Ramani
• Fall 2006: Dan Cranston, Nitish Korula, and Kevin Milans
• Spring 2007: Kevin Milans
• Fall 2008: Reza Zamani-Nasab
• Spring 2009: Alina Ene, Ben Moseley, and Amir Nayyeri
• Spring 2010: David Morrison, Kyle Fox, and Rachit Agarwal
• Fall 2010: Alina Ene
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Copyright 1999–2011 Jeff Erickson. Last update July 8, 2011.
This work may be freely copied and distributed, either electronically or on paper.
It may not be sold for more than the actual cost of reproduction, storage, or transmittal.
This work is licensed under a Creative Commons Attribution-NonCommercial-Share Alike 3.0 United States License.
For license details, see http: // creativecommons.org / licenses / by-nc-sa / 3.0 / us / .
For the most recent edition of this work, see http: // www.cs.illinois.edu / ~jeffe / teaching / algorithms / .

Shall I tell you, my friend, how you will come to understand it?
Go and write a book on it.
— Henry Home, Lord Kames (1696–1782), to Sir Gilbert Elliot
You know, I could write a book.
And this book would be thick enough to stun an ox.
— Laurie Anderson, “Let X=X”, Big Science (1982)
I’m writing a book. I’ve got the page numbers done,
so now I just have to fill in the rest.
— Stephen Wright
About These Notes
This course packet includes lecture notes, homework questions, and exam questions from algorithms
courses I taught at the University of Illinois at Urbana-Champaign in Spring 1999, Fall 2000, Spring
2001, Fall 2002, Spring 2004, Fall 2005, Fall 2006, Spring 2007, Fall 2008, Spring 2009, Spring 2010,
and Fall 2010. These lecture notes and my videotaped lectures were also offered over the web in Summer
1999, Summer 2000, Summer 2001, Fall 2002, and Fall 2005 as part of the UIUC computer science
department’s online master’s program. Lecture notes were posted to the course web site a few days (on
average) after each lecture. Homeworks, exams, and solutions were also distributed over the web.
Most (but not all) of the exercises at the end of each lecture note have been used at least once in
a homework assignment, discussion section, or exam. You can also find a near-complete collection of
homeworks and exams from past semesters of my class online at http: // www.cs.illinois.edu / ~jeffe /
teaching / algorithms / . A large fraction of these exercises were contributed by some amazing teaching
assistants:
Aditya Ramani, Alina Ene, Amir Nayyeri, Asha Seetharam, Ben Moseley, Brian Ensink, Chris
Neihengen, Dan Bullok, Dan Cranston, David Morrison, Johnathon Fischer, Ekta Manaktala,