Engineering Questions with Answers - Multiple Choice Questions
MCQs on Lexical Analyser – 2
1 - Question
The process of forming tokens from an input stream of characters is called __________
a) Liberalisation
b) Characterisation
c) Tokenization
d) None of the mentioned
View Answer
Answer: c
Explanation: The process of forming tokens from an input stream of characters is called tokenization.
2 - Question
When expression sum=3+2 is tokenized then what is the token category of 3?
a) Identifier
b) Assignment operator
c) Integer Literal
d) Addition Operator
View Answer
Answer: c
Explanation:
Lexeme
Token category
Sum "Identifier" = "Assignment operator" 3 "Integer literal" + "Addition operator" 2 "Integer literal" ; "End of statement".
3 - Question
Which grammar defines Lexical Syntax?
a) Regular Grammar
b) Syntactic Grammar
c) Context free Grammar
d) Lexical Grammar
View Answer
Answer: d
Explanation: The specification of a programming language often includes a set of rules, the lexical grammar, which defines the lexical syntax.
4 - Question
Two Important lexical categories are __________
a) White Space
b) Comments
c) None of the mentioned
d) White Space & Comments
View Answer
Answer: d
Explanation: Two important common lexical categories are white space and comments.
5 - Question
It has encoded within it information on the possible sequences of characters that can be contained within any of the tokens it handles. The mentioned function is performed by?
a) Scanner
b) Parser
c) Syntactic Analyser
d) All of the mentioned
View Answer
Answer: a
Explanation: The first stage, the scanner, is FSM. It has encoded information on the possible sequences of characters that can be contained within any of the tokens it handles.
6 - Question
What goes over the characters of the lexeme to produce value?
a) Scanner
b) Parser
c) Evaluator
d) Lexical generator
View Answer
Answer: a
Explanation: In order to construct a token, the lexical analyzer needs a second stage, the evaluator, which goes over the characters of the lexeme to produce a value.
7 - Question
Lexers are often generated by a lexer generator, same as parser generators.
a) True
b) False
View Answer
Answer: a
Explanation: Lexers are often generated by a lexer generator same as parser.
8 - Question
Which one is a lexer Generator?
a) ANTLR
b) DRASTAR
c) FLEX
d) All of the mentioned
View Answer
Answer: d
Explanation: ANTLR – Can generate lexical analyzers and parsers.
DFASTAR – Generates DFA matrix table-driven lexers in C++.
Flex – variant of the “lex” (C/C++).
Ragel – A state machine and lexer generator with output in C, C++, C#, Objective-C, D, Java, Go and Ruby.
9 - Question
Which of the lexical analyser can handle Unicode?
a) Java CC
b) JFLex
c) Quex
d) All of the mentioned
View Answer
Answer: d
Explanation: JavaCC – JavaCC generates lexical analyzers written in Java.
JFLex – A lexical analyzer generator for Java.
Quex – A fast universal lexical analyzer generator for C and C++.
FsLex – A lexer generator for byte and Unicode character input for F#.
10 - Question
What is the output of a lexical analyzer?
a) Machine Code
b) Intermediate Code
c) Stream of Token
d) Parse Tree
View Answer
Answer: c
Explanation: The output given is in the form of tokens.