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Whats The Answer & How to solve such kind of Questions ?

 

asked in Theory of Computation by (167 points)   | 43 views
Try to find out counter example for each of option given
if u found any counter eg then eliminate that option
This approach will be helpful

for e.g  option a says string that do not contain bbb but this CFG generates string with bbb as substring inside it
Okay !!

Is it possible to Convert this Grammar to DFA? (If yes , How?)
Since given grammer is CFG you can't make a DFA out of it
But you can make regular expression from it which can help you answer the question but that might took some time :D
Oh right right !!
I forgot Its  a CFG so can't be converted to DFA
Thanks For the help :)

1 Answer

+1 vote
First they should have to mentioned start state here I assuming X as a start state because x is only state from which all other state are reachable, minimum length string generate by x is a

X->Y

Y-> A from here itself we can say answer is b

Now state X and Y assure that already one a is extra either at beginning or end or both side

State S,A,B ensure number of a= number of b

S,A,B cannot be reached without X hence option b is correct
answered by Boss (6.7k points)  


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