
T79.148 Introduction to Theoretical Computer Science (2 cr)
Spring 2005
This introductory course on the theory of computation covers
the basic aspects of finite automata and regular languages,
contextfree grammars and pushdown automata, Turing machines
and computability theory.
[Current]
[General]
[Lectures]
[Tutorials]
[Exams]
[Material]
[Feedback]
[Links]
Previous years:
[Autumn 2004]
[Spring 2004]
[Autumn 2003]
[Spring 2003]
[Autumn 2002]
[Spring 2002]
[Spring 2001]
[Spring 2000]
[Spring 1999]
[Spring 1998]
 A summer exam is arranged on Aug 22. The deadline for registering
is Aug 17, 12.00h. Remember that you must complete the Regis assignments before taking the exam.
 The main exam Spring 2005 is on Tuesday 17th of May (see the exam
schedule).
The deadline for registering is May 13. Remember that
you must complete the Regis assignments before taking the exam.
 There will be 13 rounds of tutorials this spring. The last round of tutorials is on week 17.
Only the groups on Tuesday 26th and Wednesday the 27th will be arranged.
Students normaly attending groups on Thursday and Friday should choose one to attend.
 Week 15, tutorial sessions on Wednesday the 13th of April from 1214 in Y228 will exceptionally
be arranged in room U262.
 The bonuspoints deadline for the Regis assignments has been postponed
by two weeks. The new deadline is the 1st of April at 23.59.
 The second round of assignments have been generated 14.2.2005. Additionally, assignments for
students who attended the Autumn 2004 course have been generated.
 The first round of computer assignments have been
generated 7.2.2005. If you have not received your id and password to the assignments
server by email, please contact the course personnel. Students who also attended
the Autumn 2004 course will get their assignments on Monday 14.2., when their old
assignments expire.
 The last day to register for the course is on Friday the 4th of February.
The registration is needed for the computer assignments.
The first batch of assignments will be generated on Monday the 7th of February.
 Due a technical problem in webtopi, all registrations to the exam 14th of February made before the
27th of January were lost. Please reregister if you intend to take the exam then.
 The Topi registration is open between 17.1 and 4.2. Please register now.
 The results for the exam 20.12.2004 are available.
 Recommended reading for Finnish students:
Ajankäyttötutkimuksen satoa eli miten saan ystäviä,
menestystä ja hyvän arvosanan tietojenkäsittelyteorian
perusteista by Harri Haanpää
(a statistical analysis of factors affecting course
performance in Spring 2004, in Finnish).
 The course consists of:
 lectures (2 h per week, in Finnish)
 tutorials (1 h per week, one group in English)
 an examination
 Registration for the course is by
TOPI.
You must register in
order to take the course, even if you were
not intending to attend the lectures or the
tutorials. (Registrations are needed for bookkeeping
purposes, specifically for generating your set of
computerised home assignments; see below.)
One of the tutorial groups (indicated below)
will be given in English and the rest in Finnish.
Registration for the tutorials opens
Mon 17 Jan at 9:00 and closes Fri 4 Feb at 16:00.
 In order to pass the course you have to:
 complete four compulsory sets of home assignments, and
 get a passing grade on the exam, as augmented by
credit earned from the tutorials.
The compulsory assignments are individually computergenerated
for each student, and are submitted over the network.
Completing these assignments is a
mandatory prerequisite
for participating in the exam.
For more details, see the computerised assignments
info page.
 Newsgroup:
opinnot.tik.tkt
Lectures by
Timo Latvala on
Thursdays 2 p.m.  4 p.m. in Lecture Hall T1 of the Computer Science
building. The first lecture is on Thu 20 Jan.
The lectures are in Finnish, and the slides will appear here
after each lecture.
The contents will likely be very close to those from previous years,
e.g. Autumn 2004.
English translations of the lecture slides from Spring 2004 are
available here.
Lecture schedule (tentative):
Week  Date  Topic 
Sipser  LewisPapadimitriou 
Lecture slides (in Finnish) 
3.  Jan 20 
Administration. Review of basic math (functions, relations, induction). 
Pp. 113, 2325  1.11.3, 1.5 
PostScript PDF 
4.  Jan 27 
Alphabets, strings and languages. Countable and uncountable sets. 
Pp. 1314, 16, 161164  1.4, 1.7 
PostScript PDF 
5.  Feb 3 
Finite automata. 
Pp. 3143  2.1 
PostScript PDF 
6.  Feb 10 
Automata minimisation. Nondeterministic finite automata. 
Pp. 4758, 275  2.2, 2.5 
PostScript PDF 
7.  Feb 17 
Regular expressions and finite automata. 
Pp. 5876  1.8, 2.3 
PostScript PDF 
8.  Feb 24 
Nonregular languages and the "pumping lemma".
Contextfree grammars and languages. Regular grammars. 
Pp. 7797  2.4, 3.1 
PostScript PDF 
9.  Mar 3 
Parse trees and derivations.
Recursivedescent parsing of LL(1) grammars. 
Pp. 9798  3.2, 3.7 (partly) 
PostScript PDF 
10.  Mar 10 
Chomsky normal form and the
CYK parsing algorithm.
Pushdown automata. 
Pp. 98114, 240241  3.3, 3.4, 3.6 
PostScript PDF 
11.  Mar 17 
The contextfree pumping ("uvwxy") lemma.
Turing machines. 
Pp. 115135  3.5, 4.1 
PostScript PDF 
12.  Mar 24 
Easter vacation. No Lecture. 
13.  Mar 31 
Multitrack and multitape Turing machines.
Nondeterministic Turing machines. 
Pp. 136140  4.3, 4.5 
PostScript PDF 
14.  Apr 7 
Recursive and recursively enumerable languages.
Turing machine encoding and universal Turing machines. 
Pp. 142145, 159168  4.2, 5.1, 5.2, 5.7 
PostScript PDF 
15.  Apr 14 
The halting problem. Undecidability. Rice's theorem.
General and contextsensitive grammars.
Linear bounded automata. The Chomsky hierarchy. 
Pp. 171174, 196  5.3, 5.4, 4.6 p. 271 
PostScript PDF 
16.  Apr 21 
Review and discussion of the course material.
Exam requirements. You can suggest to the lecturer what material should be reviewed.

Tutorials
The tutorials start the week after the first lecture. The last tutorials are on
week 17 (2627.4) (updated, see Current).
The Friday 1516 tutorial is in English, the others are in Finnish. The head assistant
of the course is Tommi Syrjänen.
Day  Time 
Location  Assistant 
Tue  1415  Y228  Matti Järvisalo 
 1516  Y228  Matti Järvisalo 
Wed  1213  Y228  Tommi Syrjänen 
 1314  Y228  Tommi Syrjänen 
Thu  1617  Y307  Emilia Oikarinen 
 1718  Y307  Emilia Oikarinen 
Fri  1415  F  Antti Hyvärinen 
 1516  F  Antti Hyvärinen  In English 
TOPI registration
for the tutorials opens
Mon 17 Jan at 9:00 and closes Fri 4 Feb at 16:00.
You must register in order to
take the course, even if you were not intending to
physically attend the tutorials. (Registrations are
needed for bookkeeping purposes, specifically for
generating your set of computerised home assignments;
see below.)
In the tutorials, there will be three home assignments and
two or three demonstration problems each week. The tutorials
are not compulsory, but bonus exam points (max 6) will be awarded
for doing the home assignments and marking them as done at the
tutorial sessions. The grading scheme for the home assignments
is as follows:
Problems solved  Bonus points 
5  1 
10  2 
15  3 
20  4 
25  5 
30  6 
The demonstration problems are likely to be 90% the same as
in the previous instalment of the course,
and are discussed at the tutorials to the extent that time permits.
In addition to the voluntary tutorials there are
four compulsory computergenerated "Regis" problem sets.
(See the info page.)
Tutorial problems: Electronic copies downloadable here
each week. Paper copies available at the
lectures, and from the rack outside the theory lab office
(TB336).
Solutions for the demonstration problems are provided here
as the course progresses.
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
ratkaisut (pdf)
problems (pdf)
 tehtävät (pdf)
problems (pdf)
Tutorial
scores.
Validity of tutorial and Regis problems and their bonus points.
In general, exams for the course are scheduled for February,
May, August, October, and December of each year. As long as that
schedule holds:

The Regis problems generated in a given autumn / spring semester
will be valid until the Feb / Oct exam in the following semester.

Fully completed Regis assignments, and any bonus points earned
in a given autumn / spring semester will
be valid until the Oct / Feb exam in the following year.
Examinations and Grading
In general, exams for the course are scheduled for February,
May, August, October, and December of each year.
The main course exam in Spring 2005 is
scheduled for Tuesday 17th May.
There is also an exam scheduled for Monday 14th February,
intended mainly for students from previous instantiations
of the course.
To participate in an exam, you must first complete your
personal computeraided Regis exercises. See the
exam requirements.
Remember also to register
for the exam. The deadline for registering for the May exam is May 13.
Grading: Exam max 60 points, tutorials max 6 points.
Min passing grade approx. 30 points (tolerance 4 p),
highest grade (5) approx. 54 points.
In the case of "close call" failures (at most 2 points
below passing) despite serious study effort
(at least 4 tutorial bonus points), there is a possibility
of getting a passing grade by solving additional tutorial
problems. To discuss this option, please contact the
lecturer after the exam has been graded.
Bonus points earned from the tutorials are added directly
to the exam points, and may help to change the exam grade
from failing to passing. Bonus points earned from Regis
assignments completed on time (see the
info page) are
only added afterwards to a passing exam grade,
and may thus help to increase the grade, but not pass the
course. Note that the Regis assignments must
in any case be completed before the exam, and extra points
are awarded only for completion by the bonus deadline April 1.
Material
 Lecture Notes:
Typeset lecture notes (in Finnish) distributed by Edita.
 Textbook(s):
The recommended English textbook for the course is
M. Sipser, Introduction to the Theory of Computation
(PWS Publishing 1997).
The former recommended
text, H. Lewis and C. Papadimitriou,
Elements of the Theory of Computation
(Prentice Hall 1998) is being phased out.
Finnish students do not need to purchase the textbook,
since the course follows closely the lecture notes.
However the Sipser book is very readerfriendly
yet insightful, so reading it on the side will help
in following the course.
 Supporting material:
 Demonstration problems and their solutions from the tutorials.
Material from Autumn 2004 is bundled together with the
lecture notes; updates available as the course progresses.
 Some of the material will be available also via this web page.
Please avoid unnecessary printing of this material
to save printers, paper and thus nature !!!
 A short introduction to set theory and relations
(by Tommi Syrjänen, in Finnish, ps/
pdf).
 An example on determinising a finitestate automaton
(by Heikki Tauriainen, in Finnish, ps/
pdf).
 An introduction to pumping lemmata and their uses
(by Tommi Syrjänen, in Finnish, ps/
pdf).
 Solutions for one old examination (25.10.2003), in Finnish,
ps/
pdf
 Examination requirements are available.
 Mallitentti vm 2001
(ps/
pdf),
vastaukset
(ps/
pdf).
A sample examination from 2001
(ps/
pdf).
 Tentti/exam 11.2.2002:
tehtävät
(pdf),
problems
(pdf),
tulokset/results.
 Tentti/exam 8.5.2002:
tehtävät
(pdf),
problems
(pdf),
tulokset/results.
 Tentti/exam 12.8.2002:
tehtävät
(pdf),
problems
(pdf),
tulokset/results.
 Tentti/exam 28.10.2002:
tehtävät
(pdf),
problems
(pdf),
tulokset/results.
 Tentti/exam 17.12.2002:
tehtävät
(pdf),
problems
(pdf),
tulokset/results.
 Tentti/exam 3.2.2003:
tehtävät
(pdf),
problems
(pdf),
tulokset/results.
 Tentti/exam 7.5.2003:
tehtävät
(pdf),
problems
(pdf),
tulokset/results.
 Tentti/exam 18.8.2003:
tehtävät
(pdf),
problems
(pdf).
tulokset/results.
 Tentti/exam 25.10.2003:
tehtävät
(pdf),
problems
(pdf).
tulokset/results
ratkaisut
(pdf).
 Tentti/exam 19.12.2003:
tehtävät
(pdf),
problems
(pdf).
tulokset/results.
 Tentti/exam 16.2.2004:
tehtävät
(pdf),
problems
(pdf).
tulokset/results.
 Tentti/exam 13.5.2004:
tehtävät (pdf),
problems (pdf).
tulokset/results.
 Tentti/exam 23.8.2004:
tehtävät (pdf),
problems (pdf).
tulokset/results.
 Tentti/exam 23.10.2004:
tehtävät (pdf),
problems (pdf).
tulokset/results.
 Tentti/exam 20.12.2004:
tehtävät (pdf),
problems (pdf).
tulokset/results.
 Tentti/exam 14.02.2005:
tehtävät (pdf),
problems (pdf).
tulokset/results.
 Tentti/exam 17.05.2005:
tehtävät (pdf),
problems (pdf).
tulokset/results.
 Tentti/exam 22.08.2005:
tehtävät (pdf),
problems (pdf).
tulokset/results.
 Tentti/exam 27.10.2005:
tehtävät (pdf),
problems (pdf).
tulokset/results.
Feedback
Please provide feedback on the course via the DCSE department's
course feedback system. Filling in the feedback form is
rewarded by one bonus exam point, used to increase any passing
grade earned from the course.
The feedback system will open 2nd of May. The questionare will
close on May 20.
Summaries of feedback from previous courses:
Autumn 2003
Spring 2003
Autumn 2002,
Spring 2002.
Links
Some fun links that are related to the course contents, but
not part of the official course material.
[TCS main]
[Contact Info]
[Personnel]
[Research]
[Publications]
[Software]
[Studies]
[News Archive]
[Links]
Latest update: 15 November 2005.
Timo Latvala
