grammar

Question

Trailing symbols of E

E -> E + T | T

T -> T * F | F

F -> (E) | id

Comments

https://cs.stackexchange.com/questions/4716/understanding-leading-and-trailing-operations-of-an-operator-precedence-grammar

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Thanku so much. . @Shivam Chauhan

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I think FOLLOW(E) = {$, +, )}

Answer 1

Trailing (E) ={ *,+,),id }

please refer here: 1) http://epgp.inflibnet.ac.in/epgpdata/uploads/epgp_content/S000007CS/P001069/M017515/ET/1474627013Module12_Content_final.pdf

2) https://gateoverflow.in/53959/gate-compiler-design

Comments

but id is also given as the solution

Answer 2

Terminal	first	follow
E	(,id	$,+,)
T	(,id	$,+,),*
F	(,id	$,+,),*

Comments

yes this is correct

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@Akash Mittal

Refer this link Trail(E) is not same as Follow(E)

https://cs.stackexchange.com/questions/4716/understanding-leading-and-trailing-operations-of-an-operator-precedence-grammar

Answer 3

 Trail : Any terminal which is present at the last of a right sentential form (and not the sentence) which is derived from a non-terminal is the trailing of that non-terminal.

Trail(E) :

E→E+T    --In this the trailing is '+'

E→E+T∗F [using T→T∗F] -- Here trailing is '∗'

E→E+T∗(E) [using F→(E)Here trailing is ')'

(from E+T∗F) →E+T∗id [using F→id] -- Here trailing is 'id'

therefore

trail(E) = {+,∗,),id}

Similarly for T={ * , id, )}

E→ E+T

       E+T*F     or  E→E+T*id

       E+T*(E)

 for F={ id, )}

E→ E+T

       E+T*F

       E+T*(E)       or   E+T*id