CS215, Theory of Computation, Winter 2017
Home Page
Instructor: Marek Chrobak, Chung Hall 354, 8272244,
marek@cs.ucr.edu.
Office hours: Monday 23PM.
Schedule: MWF 4:10500 PM, INTS 2130. Starting Feb. 27, changed
to TR 2:103:00 PM, PRCE 3374.
Textbook: M. Sipser,
Introduction to the Theory of Computation.
Grading: Homeworks 25%, Entrance Quiz 5%,
Midterm 25%, Final 45%.
Course grades are expected to be determined as follows:
A = 85100%, B = 7584%, C = 6574%.
Academic Honesty Policy:
All students must print, read and
sign the academic integrity statement .
Return the signed statement by Monday, January~23.
Entrance Quiz. Wednesday, January 18, 25 minutes.
Quiz syllabus
Sample quizzes:
Midterm. Wednesday, February 15.
Syllabus (tentative)
Sample midterms:
Final: Saturday March 18th, 8:00am10:30am, SPR 2212.
Samples:
Homework Assignments.
There will be 5 homework assignments. They will be posted every second Monday,
starting January 9, and will be due two weeks later (except for the last one).
Homework assignments are designed for groups of two students.
Each group submits one paper with two names on it.
Each assignment will have three problems that need to be solved.
Although it is not recommended,
you are allowed to work on homework assignments by yourself, in which
case you should only solve the first two problems (not just any two).
All homework assignments must be neatly typed and formatted in LaTeX.
Papers must be written in a grammatically correct English. The solutions must
be complete, well organized, and presented with
clarity and rigor. Prior to submitting your first assignment
you must read the posted guidelines for homework papers
and follow them throughout the quarter. Incorrect or poorly written homework assignments
will be returned (and lose 20% of credit), and students will be given
two extra days to correct them.

Homework 1,
due Monday, January 23
hw1.tex /
macros.tex (source files)

Homework 2,
due Monday, February 6
hw2.tex /
macros.tex (source files)

Makeup Homework 2,
due Tuesday, February 28
hw2.tex

Homework 3,
due Monday, February 20 (extended to Thursday, March 2)
hw3.tex (source file)

Homework 4,
due Firday, March 10 (5PM)
hw4.tex (source file)

Homework 5,
due Friday, March 17 (5PM)
hw5.tex (source file)
 Week 1: January 9  January 13
THINGS TO DO during the first week
Topics:
 Week 2: January 16  January 20
Monday, January 16: No class
Wednesday, January 18: Entrance Quiz (25 minutes)
Topics:
 Variants of Turing machines: multitape TM's, other
 Nondeterministic TM's (Section 3.2)
 Enumerators (Section 3.2)
 Algorithms and ways to describe them, encodings (Section 3.3)
 The Chomsky Hierarchy
 Closure properties
 Week 3: January 23  January 27
Topics:
 Decidable languages and problems (165183)
 undecidability of A_{TM}, universal Turing Machine
 NonTuringrecognizable languages
 Reducibility, undecidable problems (189211)
 Week 4: January 30  February 3
Topics:
 Reducibility, undecidable problems (189211)

Undecidability of ALL_CFG
 Post Correspondence Problem (189211)
 Time complexity (247256)
 Week 5: February 6  February 10
Topics:
 Class P (256263)
 Class NP (246270)
 NPcompleteness (271294)
 Week 6: February 13  February 17
Wednesday, February 15: Midterm
Topics:
 NPcompleteness (271294)
`
 3SAT, VertexCover
 Week 7: February 20  February 24
February 20: No class
Topics:
 NPcompleteness, cont.
 IndSet, Clique, HamCycle
 PARTITION, weak vs strong NPcompleteness, pseudopolynomial algorithms
 Relation between complexity classes
 Space complexity (303309)
 Week 8: February 27  March 3
Topics:
 PSPACEcompleteness (309320)
 Week 9: March 6  March 10
Topics:
 Classes L and NL (320328)
 Logspace reductions, completeness in NL
 Completeness in P

NL equals coNL
 Time and space hierarchies
 Week 10: March 3  March 17
Topics:
 Approximability of NPcomplete problems
 Approximating Vertex Cover
 Approximation algorithms: TSP, Euclidean TSP, Knapsack (approximation scheme)
Homework Template in LaTeX:
A Turing Machine template in LaTeX:
LaTeX resources
 J. Hopcroft, R. Motwani, J. Ullman,
"Introduction to Automata Theory, Languages
and Computation", AddisonWesley, 2001
 C.H. Papadimitriou,
"Computational Complexity",
AddisonWesley, 1994
 H.R. Lewis, C.H. Papadimitriou,
"Elements of the Theory of Computation",
Prentice Hall, 1981
Good causes (not related to class)
