questions on nfa and dfa..

Posted by Loop on Stack Overflow See other posts from Stack Overflow or by Loop
Published on 2010-04-24T02:31:51Z Indexed on 2010/04/24 2:33 UTC
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regex

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nfa

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dfa

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homework

Hi Guys... Hope you help me with this one....

I have a main question which is ''how to judge whether a regular expression will be accepted by NFA and/or DFA?

For eg. My question says that which of the regular expressions are equivalent? explain... 1.(a+b)*b(a+b)*b(a+b)*

2.a*ba*ba*

3.a*ba*b(a+b)*

do we have to draw the NFA and DFA and then find through minimisation algorithm? if we do then how do we come to know that which regular expression is accepted by NFA/DFA so that we can begin with the answer? its so confusing....

Second is a very similar one, the question asks me to show that the language (a^nb^n|n>1} is not accepted by DFA...grrrrr...how do i know this? (BTW this is a set of all strings of where a number of a's is followed by the same number of b's)....

I hope I explained clearly well....

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