CS606 Midterm Online Quiz

CS606-Midterm

1 / 50

When generating a lexical analyzer from a token description, the item sets (states) are constructed by two types of “moves”: character moves and ____ moves.

none of given

2 / 50

Front end of two pass compiler takes________ as input.

Intermediate representation

None

Machine code

Source code

3 / 50

The transition graph for an NFA that recognizes the language ( a | b)*abb will have following set of states.

{0,1,2,3}

{0}

{0,1}

{0,1,2}

4 / 50

In LL1() parsing algorithm _________ contains a sequence of grammar symbols.

Stack

Link list

Array

None

5 / 50

Left factoring is enough to make LL1 grammar

TRUE

FALSE

6 / 50

____is evaluated to yield a value.

Command

Expression

Declaration and Command

Declaration

7 / 50

Left factoring of a grammar is done to save the parser from back tracking.

FALSE

TRUE

8 / 50

Consider the grammar

g, h, i, $

g, i

9 / 50

This grammar contains a reduce-reduce conflict. If a DFA states contains both [X → α •, a] and [Y → β •, a], then on input “a” we don’t know which production to reduce with. This is called a reduce-reduce conflict. Usually due to gross ambiguity in the grammar.

FALSE

TRUE

10 / 50

Compilers are sometimes classified as.

All of the given

Multi pass

Single pass

Load and go

11 / 50

The transition graph for an NFA that recognizes the language ( a | b)*abb will have following set of states.

{0,1,2,3}

{0,1}

{0}

{0,1,2}

12 / 50

Intermediate Representation (IR) stores the value of its operand in

Hard disk

Registers

Memory

Secondary storage

13 / 50

Follow of B is ____ .

g, h, i, $

g, i

14 / 50

Which of the statement is true about Regular Languages?

Regular Languages are the most popular for specifying tokens.

Regular Languages are based on simple and useful theory.

Regular Languages are easy to understand.

All of the given

15 / 50

AST summarizes the grammatical structure with the details of derivations.

TRUE

FALSE

16 / 50

Compilers are sometimes classified as.

Single pass

Multi pass

Load and go

All of the given

17 / 50

In DFA minimization we construct one ______ for each group of states from the initial DFA.

None of given

PDA

NFA

State

18 / 50

LR parsers can handle _______ grammars.

file-recursive

Left-recursive

Start-recursive

End-recursive

19 / 50

In a transition table cells of the table contain the ________ state.

Next state

Previous state

Reject state

None of the given

20 / 50

A lexical analyzer generator automatically constructs a _____ that recognizes tokens.

None of the given

PDA

21 / 50

Front end of two pass compiler takes________ as input.

Source code

Machine Code

Intermediate Representation (IR)

None of the Given

22 / 50

In LL1() parsing algorithm _________ contains a sequence of grammar symbols.

Array

Link list

None

Stack

23 / 50

In Flex specification file different sections are separated by ________ .

24 / 50

_______ algorithm is used in DFA minimization.

Hopcroft’s

Robert’s

James’s

None of given

25 / 50

In a transition table cells of the table contain the ________ state.

Reject state

Next state

Previous state

None of the given

26 / 50

Functions of Lexical analyzer are?

Removing constants, identifiers and keywords

Removing comments

Removing white space

All of the given

27 / 50

Which of the statement is true about Regular Languages?

All of the given

Regular Languages are based on simple and useful theory.

Regular Languages are the most popular for specifying tokens.

Regular Languages are easy to understand.

28 / 50

_______ of a two-pass compiler is consists of Instruction selection, Register allocation and Instruction scheduling.

Back end

Start

Front end

None of given

29 / 50

LR parsers can handle _______ grammars.

file-recursive

Left-recursive

Start-recursive

End-recursive

30 / 50

We can get an LL(1) grammar by _______ .

Applying left factoring

Removing left recurrence

None of the given

Removing left recurrence and Applying left factoring

31 / 50

For each language to make LL(1) grammar, we take two steps, 1st is removing left recurrence and 2nd is applying fin sequence.

FALSE

TRUE

32 / 50

Optimal registers allocation is an NP-hard problem.

TRUE

FALSE

33 / 50

In multi pass compiler during the first pass it gathers information about __________ .

Declarations

Static information

Bindings

None

34 / 50

_______ of a two-pass compiler is consists of Instruction selection, Register allocation and Instruction scheduling.

Backend

Frontend

Start

35 / 50

NFA is easy to implement as compared to DFA.

TRUE

FALSE

36 / 50

In DFA minimization we construct one ______ for each group of states from the initial DFA.

None of given

State

PDA

NFA

37 / 50

A grammar is LR if a ------ shift reduce-reduce parser can recognize handles when they appear on the top of stack.

left-to-right

left-to-reverse

left-to-rise

None of the given

38 / 50

Flex is an automated tool that is used to get the minimized DFA (scanner).

FALSE

TRUE

39 / 50

____________avoid hardware stalls and interlocks.

Instruction scheduling

None of given

Instruction selection

40 / 50

Front-end of a two pass compiler is consists of Scanner.

FALSE

TRUE

41 / 50

One of the core tasks of compiler is to generate fast and compact executable code.

FALSE

TRUE

42 / 50

LL(1) parsing is called non-predictive parsing.

FALSE

TRUE

43 / 50

Lexical Analyzer generator _______ is written in Java.

None of given

Jlex

Complex

Flex

44 / 50

Lexical Analyzer generator _______ is written in Java.

None of given

Jlex

Flex

Complex

45 / 50

Lexer and scanner are two different phases of compiler

FALSE

TRUE

46 / 50

Bottom-up parsers handle a ________ class of grammars.

Large

none of the given

medium

small

47 / 50

In Back End module of compiler, optimal register allocation uses______ .

O(log n)

None of the given

O(n log n)

N P-Complete

48 / 50

Can a DFA simulate NFA?

Yes

Sometimes

49 / 50

In parser the two LL stand(s) for ____________ .

All of the given

left-most derivation

Left-to-right scan of input

None of the given

50 / 50

Recursive _____ parsing is done for LL(1) grammar.

Forward

Decent

Backward

Ascent

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