What are the main functions of a lexical analyzer? List the various error recovery strategies in lexical analysis.[2012]
2. Importance of Lexical Analyzer
Why is a lexical analyzer essential? Explain.[2015]
3. Tokens
What do you mean by a token? Describe different types of tokens.[2021, 17, 12, 10]
4. Token, Pattern, and Lexeme
Define token, pattern, and lexeme with examples.[2019, 14, 09]Or,What do you mean by token, lexeme, and identifier?[2011]
5. Buffering in Lexical Analysis
Why is buffering used in lexical analysis? What are the commonly used buffering methods?[2021, 17]
6. Input Buffering Techniques
Describe the input buffering techniques in detail.[2020, 17]
Write down the input buffering technique with code.[2015]Or,How does an input buffer work? Write its code.[2011]
Page 144: Compiler Design and Construction
7. Regular Expressions and Definitions
Define a regular expression with an example. What are the rules for constructing regular expressions?[2012]
Define a regular definition. Give the regular definition for unsigned numbers in Pascal.[2020, 11]Or,Give the regular definition for unsigned numbers in Pascal and identifiers.[2010]
8. Lexical Syntax
Why do we use regular expressions to define the lexical syntax of a language?[2011]
9. Boolean Expressions
Briefly describe the principles of representing the value of Boolean expressions.[2013]
10. Precedence Relations
How are precedence relations used? Explain a heuristic to produce a proper set of precedence relations.[2011]
11. DFA and NFA
What is the difference between DFA and NFA?[2021, 20, 18, 16, 15, 12, 11]
Describe NFA and DFA.[2020, 19, 10]
Simplification
12. Designing Automata
Design an NFA that accepts the language aa*bb*.[2017]
13. NFA to DFA Conversion
Define NFA and DFA. Construct a DFA from the following NFA:[2014]
14. Regular Expression to NFA
What is a regular expression? Construct an NFA for the following regular expression: (a|b)abb.[2014]
15. Subset Construction
The NFA N accepts the language (a|b)*abb. Construct the DFA using the subset construction rule.[2021, 18]Or,From the following NFA N accepting the language (a|b)*abb, construct the DFA using the subset construction rule.[2016]
16. Regular Expression to DFA
Construct a DFA for the regular expression (a|b)abb.[2019, 13, 11, 10]
17. Regular Expressions for Binary Strings
Write a regular expression for each of the following sets of binary strings:[2010]
(i) All strings containing exactly one 0.
(ii) All strings where each 0 is followed by at least one 1.
(iii) All strings containing no more than three 0s.
(iv) All strings not ending in 01.
18. DFA Construction Algorithm
Write down the algorithm for constructing a DFA from a regular expression r.[2021]