ME test series DFA states

Question

The number of states in minimal DFA for strings starting with $ab^{2}$ and ending with $b$ over the alphabet $\left \{ a,b \right \}$ is__________.

// doubt: minimal string should be $ abb $ right?

Comments

5 state = 4 for abb and 1 reject state if it start from b

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Duplicate: https://gateoverflow.in/278153/me-test-series-dfa-states

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Utkarsh Joshi your DFA is invalid for strings like $abbaabb,abbaabbb,abbbab$.

for the final state on input, $b$ self-loop is there.

Answer 1

answer is 6 ,

edit: yeah the  smallest string is abb

Answer 2

RE = abb + abb(a+b) *b

Draw a DFA for above Regular Expression

(key point is : smallest string will be 'abb')

Answer 3

5 state is required

Comments

your dfa is excepting abab,  which do not start with abb.

Answer 4

6 states required as ab2 requires 4 states and b requires one state and one dead state