GATE CSE 2022 | Question: 19

Question

Consider the augmented grammar with $\{ +, {\ast}, (,),\text{id} \}$ as the set of terminals.

• $S’ \rightarrow S$
• $S \rightarrow S + R\; |\; R$
• $R \rightarrow R {\ast} P \;| \;P$
• $P \rightarrow (S)\; |\; \text{id} $

If $I_{0}$ is the set of two $\textit{LR}(0)$ items $\{ [S’ \rightarrow S.], [S \rightarrow S. + R] \}$, then $\textit{goto(closure}(I_{0}), +)$ contains exactly ______________ items.

Comments

This was my doubt too. Thanks for clearing it!

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@ruchirjain we only write 'accept' in one cell (I0, $) and not the whole row of I0?

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@jack153 yes.

Answer 1

So Goto$\text{(closure}(I_{0}),+)$ contains exactly $5$ items.

Comments

why its mention goto here, shouldnt it be action as we write action for terminals(+) and goto for non terminal

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@mk_007 exactly, may the are interested in only transition and don't care about shift or reduce

Answer 2

Answer: 5 items.

 

 

The productions of $R$ and $P$ are added because of dot $(.)$ before $R$ and $P$ non-terminals. So $goto(closure(I0, +))$ contains exactly $5$ items.

 

 

Comments

Wow, best answer

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@Argharupa Adhikary Thank you

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Great Bro!

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why its mention goto here, shouldnt it be action as we write action for terminals(+) and goto for non terminal

Answer 3

Answer 5

Closure of $I_0$ is same as $I_0$, we can find goto($I_0$) easily -

Comments

@Sachin Mittal 1 This answer is of different question sir.

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@adad20 sorry, edited now.

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S’ → S.

Edit sir @Sachin Mittal 1