LR(1) states

Question

Here what will be the lookahead for first state?

Here is given answer:

Answer 1

There is a mistake in solution, c is not going to be added as Look-ahead  But the final solution is right .

There are 2 SR conflicts in two different states

First conflicts according to the given solution is in state I-7 which is Sr conflict between E (reduce move) and c (shift move)

same conflict is in I-8 (E---> EcE.,$) (Reduce move )   ( E-->E.cE,$) (shift move on c)

Comments

can you explain why c is not going to be added as Look-ahead .

Answer 2

Solution is absolutely correct.At first I also missed this point but later got it..

In state I0 :

E -> .EcE adds another lookahead c. because of this particular production .I0 will have some other productions as

E->.abE,c

E->.EcE,c

E->.d,c

E->.e,c

and so c is added to $ as lookahead here. 

Answer 3

Well I made the DFA but i didn't find any conflicts in any state...So the answer should be option d.

Comments

I have added given solution, will you please tell me ? why they have added 'c' as lookahead in first state?

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Yes the solution is correct...Sorry my bad i made some errors while making the DFA...

and for your query why they have added {c} as their lookahead symbol..I am sending you the following link which may clear your doubt..

https://parasol.tamu.edu/~rwerger/Courses/434/lec10.pdf

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E->.E,{$}

E->.abE, {$,c} {why c here first of string followed by E is only $ }