Compiler Design

Which of the following is the most powerful parser?
(i) SLR
(ii) LALR
(iii) Canonical LR
(iv) Operator precedence

A top down parser generates
(i) Rightmost derivation
(ii) Rightmost derivation in reverse
(iii) Leftmost derivation
(iv) Left most derivation in reverse

Handle pruning forms the basis of........
(i) Bottom up parsing
(ii) Top down parsing
(iii) Predictive parsing
(iv) Recursive descent parsing

Left factoring guarantees
(i) Not occurring of backtracking
(ii) Cycle free parse tree
(iii) Error free target code
(iv) Correct LL(1) parsing table

Consider a grammar $A \to a S_1 | a S_2$. The left factored grammar produced from the grammar is
(i) $A \to a A', A' \to S_1 | S_2$
(ii) $A' \to a A, A \to a S_1 | a S_2$
(iii) $A \to a A', A' \to S_1 | S_2, S_1 \to S_1, S_2$
(iv) None of these

For a grammar G, shift reduce (S-R) conflicts are present in LALR(1) parser, if and only if
(i) The LAR (1) parser for G has S.R conflicts
(ii) The LR(0) parser for G has S.R conflicts
(iii) The SLR(1) parser for G has S.R conflicts
(iv) The SLR(0) parser for G has S.R conflicts

What are the advantages of LALR parsing over SLR and CLR methods?

Write the algorithm to compute FIRST and FOLLOW for a given grammar.

What is shift-reduce conflict?

Find the FIRST an FOLLOW form the following production:
$S \to aBDh$
$B \to cC$
$C \to bC | \epsilon$
$D \to EF$
$E \to g | \epsilon$
$F \to f | \epsilon$

Construct the predictive parsing table for the following grammars:
$S \to AaAb | BbBa$
$A \to \epsilon$
$B \to \epsilon$

What is handle? Consider the grammar:
$E \to E + E | E * E | id$
Find the handles of the right sentential forms of the reduction for the string $id + id * id$.

When a grammar is called ambiguous? Is there any technique to remove ambiguity? Justify whether the grammar is ambiguous or not?
$A \to AA | (A) | a$

Discuss about operator precedence parser.

Consider the following grammar:
$E \to E + T | T$
$T \to T * F | F$
$F \to td$
Draw a SLR state transition diagram for the above grammar. Also draw the SLR parse table.

Consider the following grammar:
$S \to CC$
$C \to cC | d$
Find the LR(1) set of items.