Testbook :

Question

$S_1 :$ Recursive decent parser takes more time and less space.

$S_2 :$ LL(1) Parser takes more time and more space.

$S_3 :$ LL(1) Parser takes less time and less space.

$S_4 :$ Recursive descent Parser takes more time and more space.

a). (1) and (2) is correct.                    b). (1) and (3) is correct
c). (2) and (4) is correct.                    d). (4) and (3) is correct.

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Ques2: Consider $2^{nd}$ production as $\tt A \rightarrow Bc|dA|\epsilon$ (I think answer given is wrong)

Comments

For question1,Recursive decent parser takes more time this is fine, because of backtracking but

how about space ?? lot of back tracking so many productions are loaded  means more space

or uses same space like stack to take correct production ??

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When we backtrack, we forget about previous state. So, same space can be used. Thus less space.

But, backtracking occurs only when grammar contains non-determinism. And we try to remove this before giving it to TDP.

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if forget previous state then there is a chance of checking same production many times( in case of many productions)??

yes if we give grammar free from non determinism then no backtracking so takes less time and space.

Answer 1

I am not even near to any Option.

Comments

Same here. I even assumed $\color{blue}{\epsilon}$ in $2^{nd}$ production. but finally left question.

So answer here would be $2$.

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yes identify wrong quetion also mean you added .66 marks :)

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Rightly said.
Have a look at first question also.

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@prashant F(B) :- {c ,d ,e,& } edit it