Somebody having good knowledge of parsing,please answer this?


Question. 1
Which of the following statements is false ?

(A) An unambiguous grammar has same left most and right most derivation(B) .

B)An LL(1) parser is a top-down parser©

© LALR is more powerful than SLR.

(D) An ambiguous grammar can never be LR(k) for any k.


(B) and © can not be the answer because LL(1) is TOP-DOWN parser and LALR is powerful than SLR. So both are TRUE.

(A) We can not have different Left Most Derivation and Right Most Derivation parse trees BUT we can certainly have different LMD and RMD for a given string.(LMD and RMD here refers to the order of various productions used for derivation which could be different.)

So A is the answer