Michael Sipser Edition 3 Exercise 1 Question 12 (Page No. 85)

Question

Let $D = \{w \mid w $ contains an even number of a’s and an odd number of b’s and does not contain the substring $ab\}.$ Give a $\text{DFA}$ with five states that recognizes $\text{D}$ and a regular expression that generates $\text{D.}$ $($Suggestion: Describe $D$ more simply$.)$

Comments

 

1. https://gateoverflow.in/132071/Michael-sipser-chp-1-3rd-edition-q-12-dfa

Answer 1

if we ignore state q3 then ouor aoutomata will accept b ((bb)*(aa)* U(aa)*(bb)*)*

Comments

Reg exp : (bb)*b + (bb)*b(aa)+