Lei Bu

bulei@nju.edu.cn

Preliminary Introduction to the Theory of Computation

• This course: A study of

abstract models of computers and computation.

• Why theory, when computer field is so practical?

• Theory provides concepts and principles, for both hardware and software that help us understand the general nature of the field.

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Why Study Automata?

A survey of Stanford grads 5 years out asked which of their courses did they use in their job.

Basics like intro-programming took the top spots, of course.

But among optional courses, formal language and automata stood remarkably high.

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How Could That Be?

Regular expressions are used in many systems. E.g., UNIX a.*b. E.g., DTD’s describe XML tags with a RE format like

person (name, addr, child*). Finite automata model protocols, electronic circuits.

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How? – (2)

Context-free grammars are used to describe the syntax of essentially every programming language. Not to forget their important role in describing natural

languages.

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How? – (3)

When developing solutions to real problems, we often confront the limitations of what software can do. Undecidable things – no program whatever can do it. Intractable things – there are programs, but no fast

programs. Automata theory gives you the tools.

Outline

Part 1: Preliminaries Mathematical Knowledge String and Language

Part 2: Finite Automata and Regular Expression

Context Free Grammar and Pushdown Automata

Turing Automata

Part 3 Modeling: Transition System Petri Net Timed and Hybrid Automata Message Sequence Chart

Part 4: Tutorials Computability Model Checking Trustworthy Software

Textbook John E. Hopcroft, Rajeev Motwani, Jeffery D.Ullman. Introduction to Automata

Theory, Languages, and Computation, 3/E. Pearson Education India, 2008. (The Cinderella Book)

Referred Reading Michael Sipser. Introduction to the Theory of Computation, 2nd Edition,Course

Technology, 2005. Derick Wood. Theory of Computation. HAPPER & ROW, 1987. Doron Peled. Software Reliability Methods. Springer, 2011

WEB http://cs.nju.edu.cn/bulei/PTC15.html

Grading

Assignment 30% Distributed in Class, due in next week.

Final Exam 70%