Computer Science 252

CS 252 Homework Assignments


Homework assignments are due by 11:59 pm on the due date.

Please upload a PDF file to Canvas containing your solutions.

Late submissions are not accepted.

Email submissions are not accepted.


Assignment Chapter Exercises/Problems Due Date
Homework 1 not assigned
Homework 2 not assigned
Homework 3 1 1.3 9 Sep 2026
Homework 4 1 1.6a, 1.6f, 1.6i, 1.6j 11 Sep 2026
Homework 5 1 1.7b, 1.7c, 1.7d, 1.7g 14 Sep 2026
Homework 6 1 1.16a, 1.16b 16 Sep 2026
Homework 7 1 1.18a, 1.18b, 1.18i, 1.18j 18 Sep 2026
Homework 8 1 1.19a, 1.19b, 1.21a, 1.21b
For problem 1.21b,
please remove state 3 first,
state 1 second, state 2 last.
21 Sep 2026
Homework 9a 1 1.29b 23 Sep 2026
Homework 9b 1 1.30, 1.53 25 Sep 2026
Homework 10 2 2.4b, 2.4e 28 Sep 2026
Homework 11 2 2.1c, 2.1d 30 Sep 2026
Homework 12 2 2.5b, 2.5e
For each of these problems,
you need to design a PDA.
Do not design a CFG and
convert it to a PDA.
Also, you don't need to give
informal descriptions
for your PDAs.
2 Oct 2026
Homework 13 2 2.11 5 Oct 2026
Homework 14 2 2.30a 9 Oct 2026
Homework 15 3 3.1d, 3.2e 12 Oct 2026
Homework 16 3 3.8b, 3.8c 14 Oct 2026
Homework 17 3 3.15d, 3.16d 16 Oct 2026
Homework 18 4 4.2, 4.3
4.3 hint:
use the EDFA decider
23 Oct 2026
Homework 19 4 4.4, 4.7
(4.4, 4.6 in 2nd edition)
26 Oct 2026
Homework 20 4 4.13, 4.16
(4.12, 4.15 in 2nd edition)
4.13 hint:
describe subset using
intersect and complement
4.16 hint:
build a DFA that accepts
any string containing 111
28 Oct 2026
Homework 21 5 5.1
(use reduction, don't
use mapping reduction)
5.1 hint:
Use the fact that ALLCFG
is undecidable
(see page 225 in the book)
(page 197 in the 2nd edition)
2 Nov 2026
Homework 22 5 5.9
(use reduction, don't
use mapping reduction)
5.9 hint:
Does T contain a TM that
recognizes the language
{01, 10}?
Does T contain a TM that
recognizes the language
{01}?
4 Nov 2026
Homework 23 5 5.4
5.4 hint:
Think of a specific
non-regular language A.
Think of a specific
regular language B.
Can you give a mapping
reduction from A to B?
6 Nov 2026
Homework 24 5 5.9
(repeat 5.9, this time
use mapping reduction)
9 Nov 2026
Homework 25 7 7.1, 7.2 13 Nov 2026
Homework 26 7 7.8, 7.21a
(7.8, 7.20a in 2nd edition)
18 Nov 2026
Homework 27 7 7.3, 7.4 20 Nov 2026
Homework 28 7 7.9, 7.12
(7.9, 7.11 in 2nd edition)
30 Nov 2026
Homework 29 7 7.5, 7.22
(7.5, 7.21 in 2nd edition)
7.22 hint:
reduce from SAT
to DOUBLE-SAT
2 Dec 2026
Homework 30 7 7.21b
(7.20b in 2nd edition)
7.21b hint:
reduce from UHAMPATH
to LPATH
4 Dec 2026