Computer Science 370
Fall 2012
Exam 2 Review
Disclaimer: I have attempted to be comprehensive in the
following, but important items may have been omitted by mistake. If
you see such an omission, please let me know, but you are responsible
for all of the lecture material to date.
The second hour exam for CSci 370 will be held on Friday, October 19, and
will cover from section 1.3 through section 2.2 of the textbook . In particular, be prepared
to:
- Give proper (formal) definitions of the terms encountered so far.
- Be able to construct an NFA from a regular expression, and a regular
expression from a DFA. In these, you will not be asked to construct
automata and regular expressions in the manner discussed in the proof of the
equivalence of languages described by a regular expression and and languages
described by a DFA, but rather to look at expressions / automata and work
out what the translation would give you.
- Be able to state and use the pumping lemma for regular languages.
Be able to say where the pumping length for a DFA comes from.
- Be able to give a formal definition of a Context-Free Grammar and of
Chomsky Normal Form for a CFG. Given a context-free grammar, be able
to construct derivations and associated parse trees. You may be asked
to construct a CFG for a simple language.
- Be able to define a Regular Grammar, and to construct one from a DFA.
- Be able to give a formal definition of a (nondeterministic) pushdown
automaton, and to say (again, formally) what it means for a PDA to accept a
string in a language.
- Be able to describe a PDA using the diagram method introduced Wednesday,
and demonstrate its use.
- (Assuming that we do this on Friday) Be able to demonstrate the
workings of a PDA on an utterance in a CFG.