Q. In a compiler, keywords of a language are recognized during

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Q. The lexical analysis for a modern computer language such as Java needs the power of which one of the following machine models in a necessary and sufficient sense?

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Q. What is the maximum number of reduce moves that can be taken by a bottom-up parser for a grammar with no epsilon- and unit-production (i.e., of type A -> є and A -> a) to parse a string with n tokens?

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Q. Consider the following two sets of LR(1) items of an LR(1) grammar.

X -> c.X, c/d
X -> .cX, c/d
X -> .d, c/d
X -> c.X, $
X -> .cX, $
X -> .d, $

Which of the following statements related to merging of the two sets in the corresponding LALR parser is/are FALSE?

1. Cannot be merged since look aheads are different.
2. Can be merged but will result in S-R conflict.
3. Can be merged but will result in R-R conflict.
4. Cannot be merged since goto on c will lead to two different sets.

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Q. The grammar S → aSa | bS | c is

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Q. Match all items in Group 1 with correct options from those given in Group 2.

Group 1 Group 2

P. Regular expression 1. Syntax analysis
Q. Pushdown automata 2. Code generation
R. Dataflow analysis 3. Lexical analysis
S. Register allocation 4. Code optimization

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Q. Which of the following statements are TRUE?

I. There exist parsing algorithms for some programming languages
whose complexities are less than O(n^3).
II. A programming language which allows recursion can be implemented
with static storage allocation.
III. No L-attributed definition can be evaluated in The framework
of bottom-up parsing.
IV. Code improving transformations can be performed at both source
language and intermediate code level.

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Q. Which of the following describes a handle (as applicable to LR-parsing) appropriately?

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Q. An LALR(1) parser for a grammar G can have shift-reduce (S-R) conflicts if and only if

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Q. Which one of the following is a top-down parser?

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Q. Consider the grammar with non-terminals N = {S,C,S1 },terminals T={a,b,i,t,e}, with S as the start symbol, and the following set of rules:

S --> iCtSS1|a
S1 --> eS|ϵ
C --> b

The grammar is NOT LL(1) because:

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Q. Consider the following two statements:

P: Every regular grammar is LL(1)
Q: Every regular set has a LR(1) grammar

Which of the following is TRUE?

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Q. Consider the following grammar.

S -> S * E
S -> E
E -> F + E
E -> F
F -> id

Consider the following LR(0) items corresponding to the grammar above.

(i) S -> S * .E
(ii) E -> F. + E
(iii) E -> F + .E

Given the items above, which two of them will appear in the same set in the canonical sets-of-items for the grammar?

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Q. A canonical set of items is given below

S --> L. > R
Q --> R.

On input symbol < the set has

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Q. Consider the grammar defined by the following production rules, with two operators ∗ and +

S --> T * P
T --> U | T * U
P --> Q + P | Q
Q --> Id
U --> Id

Which one of the following is TRUE?

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Q. Consider the following grammar:

S → FR
R → S | ε
F → id

In the predictive parser table, M, of the grammar the entries M[S, id] and M[R, $] respectively

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Q. Consider the following translation scheme. S → ER R → *E{print("*");}R | ε E → F + E {print("+");} | F F → (S) | id {print(id.value);} Here id is a token that represents an integer and id.value represents the corresponding integer value. For an input '2 * 3 + 4', this translation scheme prints

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Q. The grammar A → AA | (A) | ε is not suitable for predictive-parsing because the grammar is

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Q. Consider the grammar

E → E + n | E × n | n

For a sentence n + n × n, the handles in the right-sentential form of the reduction are

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Q. Consider the grammar

S → (S) | a

Let the number of states in SLR(1), LR(1) and LALR(1) parsers for the grammar be n1, n2 and n3 respectively. The following relationship holds good

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