Compiler Design unit 1 Quiz

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

• P-4. Q-1, R-2, S-3

• P-3, Q-1, R-4, S-2

• P-3, Q-4, R-1, S-2

• P-2, Q-1, R-4, S-3

Which data structure in a compiler is used for managing information about variables and their attributes?

• Abstract syntax tree

• Symbol table

• Semantic stack

• Parse table

In a compiler, keywords of a language are recognized during

• parsing of the program

• the code generation

• the lexical analysis of the program

• dataflow analysis

Which one of the following languages over the alphabet {0,1} is described by the regular expression: (0+1)*0(0+1)*0(0+1)*?

• The set of all strings containing the substring 00.

• The set of all strings containing at most two 0's.

• The set of all strings containing at least two 0's.

• The set of all strings that begin and end with either 0 or1

S ->aSa| bSb| a| b ;The language generated by the above grammar over the alphabet {a,b} is the set of

• All palindromes

• All odd length palindromes

• Strings that begin and end with the same symbol

• All even length palindromes

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?

• Finite state automata

• Deterministic pushdown automata

• Non-Deterministic pushdown automata

• Turing machine

Which of the following is not performed during compilation?

• Dynamic memory allocation

• Type checking

• Symbol table management

• inline expression

A lexical analyzer uses the following patterns to recognize three tokens T1, T2, and T3 over the alphabet {a,b,c}. T1: a?(b∣c)*a , T2: b?(a∣c)*b, T3: c?(b∣a)*c Note that 'x?' means 0 or 1 occurrence of the symbol x. Note also that the analyzer outputs the token that matches the longest possible prefix. If the string bbaacabc is processes by the analyzer, which one of the following is the sequence of tokens it outputs?

• T1T2T3

• T1T1T3

• T2T1T3

• T3T3

Match the following:

• P-i Q-ii R -iv S-iii

• P-iii Q-i R-ii S-iv

• P-ii Q-iii R-I S-iv

• P-iv Q-I R-ii S-iii

Yylval in lex tool is ________________.

• Local variable in Lexical analyzer

• Global variable of Lexical analyzer and parser

• Local variable in parser

• Used to share token name