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Posted by sk8tzz 
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August 24, 2006 09:40AM

Hi. I can do a normal CNF, but when there is an /\ I still get confused.

Take last 2005 exam paper q2.

S -> aXX | /\
X -> SbY | a | XYS
Y -> S | abX

Heres my question, I undestand that S is nullable, and Y is nullable because of S.

The next step explained in the the tuts, is remove the /\ and everywhere there is an S or Y on the right hand side do a substitution. But I cannot see the substition that must happen, for example is below what must happen.

S -> aXX
X -> SbY | a | XYS | Y | S
Y -> S | abX | Y

August 24, 2006 10:03AM
Could a lecturer please reply on this....
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