Automata and Complexity


Course Objective

The student is acquainted with important notions and algorithms
formal languages, automata, grammars, compilers, computability and

This course addresses foundational questions in computer science, such
- "What is a (programming) language?",
- "How can languages be recognised by computers (automata)",
- "Which problems can be solved using a class of automata?",
- "How much time and memory does solving a problem require?".

The course is divided into the following parts: automata & languages and
computability theory.

Course Content

The first part, on automata and languages, deals with the concepts of
formal language, grammar, and automaton. Two types of languages are
covered: regular and context-free languages. Regular languages are used,
e.g., in search queries, in the form of regular expressions.
Context-free languages are suitable to describe programming languages.
The automata-theoretic counterparts here are finite automata and the
more powerful pushdown automata. Pumping lemmas are discussed to
determine whether a language is regular or context-free. With each type
of language a class of grammars is associated: left-linear and
context-free grammars. Parsing algorithms are presented for context-free
languages, to determine whether a string is in the language.

In the second part of the course, on computability theory, the central
question is "Which computations can be performed on a computer?". To
reason about this question, Turing machines are introduced, as well the
Church-Turing thesis, along with examples of undecidable problems: the
halting problem and the Post correspondence problem. It is shown how
undecidability of new problems can be shown by reduction from a known
undecidable problem. Important complexity classes from the complexity
hierarchy are discussed, notably P, NP, and NP-complete, together with
the corresponding reduction arguments.

Teaching Methods

4 hours per week lectures; 4 hours per week exercise classes

Method of Assessment

The homework is mandatory for qualifying for the exam (70% of the
homework points to qualify for the exam). In case at least 90% of the
homework points is obtained, 0.5 bonus point is awarded for the final
At the end of the course there is a final exam. The overall grade is the
grade of the final exam plus the possibly 0.5 bonus point obtained for
the homework. (The bonus is only added for students that pass the exam
with a grade of at least 5.5.)

There is no resit opportunity for the homework.


Peter Linz, An Introduction to Formal Languages and Automata, Jones &
Bartlett, 4th or 5th edition

Target Audience


General Information

Course Code X_401049
Credits 6 EC
Period P4
Course Level 300
Language of Tuition English
Faculty Faculty of Science
Course Coordinator drs. J. Endrullis
Examiner drs. J. Endrullis
Teaching Staff drs. J. Endrullis

Practical Information

You need to register for this course yourself

Last-minute registration is available for this course.

Teaching Methods Seminar, Lecture
Target audiences

This course is also available as: