Explore topic-wise MCQs in Automata Theory.

This section includes 21 Mcqs, each offering curated multiple-choice questions to sharpen your Automata Theory knowledge and support exam preparation. Choose a topic below to get started.

1.

A particular BNF definition for a “word” is given by the following rules. ∷ = | | ∷ = | ∷ = | ∷ = a | b | c | ….. |y| z ∷ = 0 |1|2| …… | 9Which of the following lexical entries can be derived from < word > ?l. pickII. pickslll. c44

A. I, II Wand Ill
B. I and II only
C. I and III only
D. II and III only
Answer» E.
2.

DU-chains(Definition-Use) in complier design

A. consist of a definition of a variable and all its uses, reachable from that definition
B. are created using a form of static code analyses
C. are prerequisite for many compiler optimization including constant propagation and common sub-expression elimination
D. All of the above
Answer» E.
3.

Arrange the given compilation process in the correct order.a. Linkingb. Assemblingc. Compilingd. Pre-processing

A. d → c → b → a
B. a → c → b → d
C. d → c → a → b
D. a → b → c → d
Answer» B. a → c → b → d
4.

Access time of the symbol table will be logarithmic, if it is implemented by

A. Linear list
B. Search Tree
C. Hash Table
D. Self-organization list
Answer» C. Hash Table
5.

Lexical analysis is the _______ phase of a compiler.

A. First
B. Second
C. third
D. fourth
Answer» B. Second
6.

A lexical analyzer uses the following patterns to recognize three tokens T1, T2, and T3 over the alphabet {a,b,c}.

A. 𝑇1𝑇2𝑇3
B. 𝑇1𝑇1𝑇3
C. 𝑇2𝑇1𝑇3
D. 𝑇3𝑇3
Answer» E.
7.

In compiler, which of the following reads input characters to identify tokens?

A. Code generator
B. Code optimizer
C. Semantic analyzer
D. Lexical analyzer
Answer» E.
8.

A(n) ______ is a sequence of characters in source program that is matched by the pattern for a token.

A. Lexeme
B. Operator
C. Operand
D. Function
Answer» B. Operator
9.

A_PROGRAM_THAT_PERFORMS_LEXICAL_ANALYSIS_IS_TERMED_AS:?$

A. scanner
B. lexer
C. tokenizer
D. all of the mentioned
Answer» E.
10.

Which phase of compiler includes Lexical Analysis?$

A. 1
B. 2
C. 3
D. Its primary function, not in any phase
Answer» E.
11.

Lexers_and_parsers_are_not_found_in_which_of_the_following?$

A. compiler front end processing
B. prettyprinters
C. linters
D. none of the mentioned
Answer» B. prettyprinters
12.

The scanner outputs:

A. Stream of tokens
B. Image file
C. Intermediate code
D. Machine code
Answer» D. Machine code
13.

Which of the following is the task of lexical analysis?

A. To build the uniform symbol table
B. To initialize the variables
C. To organize the variables in a lexical order
D. None of the mentioned
Answer» B. To initialize the variables
14.

The action of parsing the source code into proper syntactic classes is known as:

A. Parsing
B. Interpretation analysis
C. Lexicography
D. Lexical Analysis
Answer» B. Interpretation analysis
15.

____________ is used for grouping up of characters into token.

A. Lexical Analyzer
B. oolex
C. jflex
D. All of the mentioned
Answer» E.
16.

Which among the following is not a tool to construct lexical analyzer from a regular expression?

A. lex
B. flex
C. jflex
D. none of the mentioned
Answer» E.
17.

The output of the lexical and syntax analyzer can stated as:

A. parse stream, parse tree
B. token tree, parse tree
C. token stream, parse tree
D. all of the mentioned
Answer» E.
18.

Statement 1 is assertion, Statement 2 is the reason

A. Statement 1 is assertion, Statement 2 is the solution
B. There is no such Statement 2
C. This is not a function of Lexical Analyzer
Answer» D.
19.

The methodology to show an error when the analyzer faces a keyword over an user’s input is based on:$

A. rule priority
B. longest match rule
C. keyword-out rule
D. none of mentioned
Answer» B. longest match rule
20.

If the lexical analyser finds a lexeme with the same name as that of a reserved word,it _________

A. overwrites the word
B. overwrites the functionality
C. generates an error
D. something else
Answer» D. something else
21.

Lexemes can be referred to as:

A. elements of lexicography
B. sequence of alphanumeric characters in a token
C. lexical errors
D. none of the mentioned
Answer» C. lexical errors