CS 154 (Section 1): Formal Languages and Computability, Spring 2008

David Scot Taylor
212 MacQuarrie Hall
Assistant Professor
Dept. of Computer Science
San Jose State University
Phone: (408) 924-5124 (email works better)
Email: taylor "at" cs.sjsu.edu

My office hours for Spring 2008 : Tue/Thur 8:30-9:00, (the last 10 minutes in MH222), 11:50-13:30 (the last 10 minutes in MH223)
Note: I will be on leave until March 17.

Section 1: MH 223, Tue/Thur 13:30-14:45
Adel Atta will teach until David Taylor's return. He will hold office hours in DH282, on Tuesdays and Thursdays, from 10:30-1:25.

Course Information

Information about the course, prerequisites, grading, and policies can be found on the Course Greensheet. Additionally, Adel Atta will be using the website http://groups.yahoo.com/group/CS154, and can be reached at cs154 "at" yahoo "dot" com.

Announcements

Tentative Schedule

A tentative schedule can be found here.

Classes So Far

Date Topics Covered Readings
(Linz, Formal Languages and Automata, 4th Ed.)
Homework
May 8 Reductions, Halting Problem, Rice's Theorem, Post's correspondence problem, Closure properties Chapter 11.4, 12.1, 12.2, 12.3 (no proof) Do not turn in: 12.2-2 (remember reduction we saw in class) and 12.3-1. Come with questions Tuesday. Consider the final review sheet.
May 6 Diagonalization, undecidability of the acceptance language (given a TM M and a string w, does M accept w?). Chapter 11.1, 12.1. Also people requested a JFLAP machine for the problem due today. Due May 8: Think about 12.1-12 (not collected), given the fact that we have proved the acceptance problem is undecidable.

Due May 13: 11.1-9, 11.1-10.

May 1 Turing Machine Variants, and Turing Machine Languages Chapter 10 (all except 10.5. You may skip p. 254-256, 260) and start Chapter 11 (first 3 pages) Due May 6: 10.4-1, 10.4-4, 10.4-7. Note, this assignment will require you to read section 10.4 in some detail, as the questions cannot be answered without details from the section.
April 29 Nondeterministic Turing Machines, Universal Turing Machines Chapter 10.3, 10.4

The deterministic and non-deterministic machines we saw in class (if you want to download them and open them with JFLAP.)

Due May 6 (probably with something else assigned on May 1): Consider a multi-tape (one input tape, one initially blank working tape) Turing Machine (See section 10.2 for a more formal definition). Construct a 2 tape Turing Machine to again recognize the language of 9.1-8 in JFLAP. You ARE allowed to use the (S)tationary move option. You ARE ALSO allowed to use non-determinism. You are NOT allowed to use more than 6 states, including the accept state. (You do not NEED more than 4 states.)
April 24 More Programming Turing Machines Chapter 9 (all) Due May 1: We informally showed in class that a Turing Machine which allows you to remain (S)tationary on the tape, as well as moving (L)eft and (R)ight, is not more powerful than one which only allows (L) and (R) moves. Prove this more rigorously, using the formal definition of a Turing Machine.
April 22 Midterm 2 returned, start Turing Machines Chapter 9.1 Due 4/29: 9.1-8 (page 237) using JFLAP.
April 17 Midterm 2
April 15 CF pumping lemma example, review for exam Midterm is comprehensive. The outline of questions was given on 4/10. None
April 10 More CFG/PDA practice, CFL closure properties, Touch on DPDAs, touch on CFG transformations and Chomsky Normal Form, Start CF Pumping Lemma 8.2 through p. 218, skimmed 7.3, 6.1, 6.2 through p. 167, start 8.1 Due 4/15: All concrete examples given in the Practice/Format for MT2.
April 8 More CFGs, PDAs, CFG to PDA 7.1, 7.2 (covered differently than text, due to skipped Chapter 6) Due 4/10: 7.1-4b, using JFLAP to run some example. What happens if you change the language to remove the 'c'? Run some inputs on that language too.
April 3 Context Free Grammars, start PDA 5.1, 5.2 (skip bottom 139, top 140), 7.1 Due 4/10: 5.1-3, 5.1-7c, 5.2-7, 5.2-11, 5.2-12, 7.1-4c
April 1 Regular grammar/automata conversions, closure rules, and the pumping lemma 3.3, 4.1, 4.2, 4.3 Due 4/3: 3.3-1, 4.1-2b, 4.2-6 (your algorithm here should use, as building blocks, procedures we have already seen, without the need to repeat them), 4.3-4c by pumping lemma AND closure.
March 20 2007 Midterm review, catch-up All of Chapters 1-3 and 4.3, and P.L. handout from 3/20. This is a lot of reading, but it is material you officially covered in the first 1.5 months of the course, and which we have now reviewed. Due 4/3 (but best by 4/1): Homework assigned 3/22
March 18 Re-Introduction, the big picture, and the pumping lemma Pumping Lemma Handout Due 3/20: Midterm 1, Spring 2007, excluding question 7 (handed out in class)
January 24 Introductions and Administrivia Chapter 1.1

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