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Question

a*b*b (a+ (ab)*)* b*

shortest string generated by this RE?

Comments

b is is min string here.

Answer 1

Here b is Compulsory generated character

Everything else we can put *=0

So" b" is the Minimum String that can be generated Using above RE.

Answer 2

Given:

a*b* b(a+ ((ab)*)* b*
sol:

a*b* b(a+((ab)*)* b*

=>a*b* b (a*+((ab)*)* b*

=>a*b* b (a*+(ab)*) b* (i.e.,((ab)*)*=(ab)* )

=>∈ b(∈+(∈))∈ (i.e.,any thing power closure it include empty string = ∈)

=>so the min string accepted by the regular expression is "b"

Comments

It's a*b*b (a+ (ab)*)* b* not a*b* ba+ ((ab)*)* b* ...

Answer 3

Definitely b will be the minimum...

Comments

after putting all as epsilon b is minimal u get