Compiler Design : First & Follow

Question

is it correct ?

Comments

Oh my bad I forget to put C = epsilon in the first production of A.

All your first and follow are correct.

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Since C derive epsolon, a will sldo come in first of A

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First of all you have to remove the left recursion present in the grammar i.e. B-->BaAC | C , then proceed further.

Answer 1

First remove left recursion from the grammer

S -> AB
A -> Ca | $\epsilon$
B -> cB'
B' -> aACB' | $\epsilon$
C -> b | $\epsilon$

first ( S ) = { b, c, a }
first (A ) = {b, a, $\epsilon$ }
first (B) = {c}
first (C) = {b, $\epsilon$ }

follow (S) = { dollar }
follow (A) = {c, b , dollar, a}
follow (B) = { dollar , a} [a because first of B' is subset of follow of B]
follow (C) = {dollar , a}

Yes all are correct.

Comments

https://stackoverflow.com/questions/27700626/confusion-in-finding-first-and-follow-in-left-recursive-grammar
https://sites.tufts.edu/comp181/2013/10/05/first-and-follow-sets/

Some more links that might help you :)

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can anyone explain how 'a' has come in the above follow set of bothA and B

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all your first set and follow set is true.

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Can u explain how is ‘c’ coming in the First of S