CS 390 Test II Questions


March 28, 1996


1. Find an NFA- tex2html_wrap_inline29 for the regular expression tex2html_wrap_inline31 .

2. Let tex2html_wrap_inline33 denote the set of states that can be reached from p by k tex2html_wrap_inline29 -transitions (i.e. through k tex2html_wrap_inline29 -transitions) in an NFA- tex2html_wrap_inline29 . Answer the following questions.

(a) Inductively (i.e. recursively) define tex2html_wrap_inline33 for natural numbers k.
(b) Prove by induction that for any natural number k tex2html_wrap_inline53 .

Note that tex2html_wrap_inline55 is defined inductively for a set S of states as follows:
Basis: tex2html_wrap_inline59
Induction: For any state q, if tex2html_wrap_inline63 , then tex2html_wrap_inline65 .
Extremal Clause

3. Find an NFA equivalent to the NFA- tex2html_wrap_inline29 of Fig. 1 on the next page.

4. Find an FA equivalent to the NFA of Fig. 2 on the next page.

5. Find the (Kleene) star (i.e. *) of the NFA- tex2html_wrap_inline29 of Fig. 3 on the next page.

Click here for figures.


S. Toida
Tue Jan 14 11:54:24 EST 1997

Go to 1996 Test 2 Solutions

Back to CS390 1996 Test 2

Back to CS390 Past Tests