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Syllabus

NEC Computer · Practice

Chapters & sets

1. Basic Electrical and Electronics

Basic Electrical

Set 1106

Basic Electronics

Set 171 Set 233

2. Digital Logic and Microprocessor

Digital Logic

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 749 Set 851 Set 950 Set 1050 Set 1150 Set 1232

Microprocessor

Set 150 Set 250 Set 350 Set 445 Set 550 Set 650 Set 720 Set 850 Set 969

3. Programming Language and Its Applications

Mixed chapter MCQs

Set 150 Set 249 Set 349 Set 451 Set 540

4. Computer Organization and Embedded System

Mixed chapter MCQs

Set 150 Set 249 Set 350 Set 450 Set 550 Set 650 Set 750 Set 849 Set 950 Set 1050 Set 1150

5. Concept of Computer Network and Network Security System

Basic Networking

Set 150 Set 253

Advanced Networking

Set 150 Set 250 Set 350 Set 450 Set 550 Set 655

6. Theory of Computation and Computer Graphics

Theory of Computation

Set 150 Set 250 Set 360

Computer Graphics

Set 150 Set 251 Set 350 Set 450 Set 550

7. Data Structures and Algorithm, Database System and Operating System

8. Software Engineering and Object-Oriented Analysis & Design

Mixed chapter MCQs

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 750 Set 926

9. Artificial Intelligence and Neural Networks

Mixed chapter MCQs

Set 150 Set 317 Set 450 Set 550 Set 650 Set 750 Set 850 Set 932

10. Project Planning, Design and Implementation

Engineering Drawing

Set 150 Set 267

Engineering Economics

Set 168

Project Planning & Scheduling

Set 188

Project Mangement

Set 150

Engineering Professional Practice

Set 120

Engineering Regulatory Body

Set 130

Theory of Computation Set 3

60 questions

Question 1

The set

A = {a^n b^n c^n / n = 1, 2, 3, \ldots}

50

is an example of

A.
Regular language
B.
Non context free language
C.
Context free language
D.
None of these

Question 2

The intersection of CFL and a regular language

A.
Need not be regular
B.
Is always regular
C.
Need not be context free
D.
None of these

Question 3

Choose the correct statements:

A.
The power of DFSM and NDFSM are same.
B.
The power of DFSM and NDFSM are different.
C.
The power of DPDM and NDPDM are different.
D.
Both (A) and (C) above.

Question 4

Which of the following is accepted by an NDPDM but not by a DPDM?

A.
All strings in which a given symbol is present at least twice
B.
Even palindromes.
C.
Strings ending with a particular alphabet.
D.
None of these.

Question 5

Bounded minimization is a technique for

A.
Proving whether a promotive recursive function is Turing computable or not.
B.
Providing whether a primitive recursive function is a total function or not.
C.
Generating primitive recursive functions.
D.
Generating partial recursive functions.

Question 6

Universal Turing machine influenced the concept of

A.
Stored program computers
B.
Interpretive implementation of programming language
C.
Computability
D.
All of these

Question 7

The statement "A Turing machine can't solve halting problem" is

A.
True
B.
Still at open question
C.
False
D.
All of these

Question 8

If there exists a TM which when applied to any problem in the class, terminates, if the correct answer is yes and may or may not terminate otherwise is said to be

A.
Stable
B.
Partially solvable
C.
Unstable
D.
Unstable

Question 9

The vernacular language English, if considered a formal language is a

A.
Regular language
B.
Context sensitive language
C.
Context free language
D.
None of these

Question 10

P, Q, R are three languages, if P and R are regular and if PQ = R then

A.
Q = R
B.
Both A and B
C.
Q = P
D.
None of these

Question 11

Consider the grammar

S \rightarrow PQ/SQ/PS

\

P \rightarrow X,

\

Q \rightarrow Y

\ To get string of n terminals, the number of productions to be used is

A.
N
B.
n + 1
C.
2^n
D.
2^{n-1}

Question 12

The following grammar

S \rightarrow aab/bac/ab

\

S \rightarrow abb/ab

\

S \rightarrow aS/b

\

B \rightarrow bab/b

A.
CFG
B.
Context sensitive
C.
Regular
D.
None of these

Question 13

Let

A = {0,1}

and

L = A^*

. Let

R = {0^n, n > 0}

then the language

L \cup R

and

R

are respectively.

A.
Regular, regular
B.
Regular, not regular
C.
Not regular, regular
D.
Not regular, not regular

Question 14

Which of the following is not possible algorithmically?

A.
Regular grammar to context free grammar
B.
Non-deterministic finite state Automata to deterministic FSA
C.
Non-deterministic PDA to deterministic PDA
D.
None of these

Question 15

As FSM can be used to add two given integers. That is

A.
True
B.
False
C.
May be true
D.
None of these

Question 16

A grammar is said to be in CNF, if all the productions are of the form

A \rightarrow BC

or

A \rightarrow a

. Let

G

be a CFG in CNF. To derive a string of terminals of length

x

, the number of production to be used is

A.
$2x - 1$
B.
$2x$
C.
$2x + 1$

Question 17

In given fig

A.
Both are equivalent
B.
The first FSM accepts nothing
C.
The second FSM accepts $\epsilon$ -only
D.
None of these

Question 18

The number of tokens in the Fortran statement DO 10 I = 1.25 is

A.
3
B.
4
C.
5
D.
None of these

Question 19

The word 'formal' in formal languages means

A.
The symbols used have well-defined language meaning
B.
They are unnecessary in reality
C.
Only the form of the string of symbols is significant
D.
None of these

Question 20

If

A = {0, 1}

, the number of possible strings of length 'n' is

A.
$n!$
B.
$n \times n$
C.
$n^n$
D.
$2^n$

Question 21

A mealy machine

A.
May be machine
B.
Has an equivalent more
C.
Only context-free grammar
D.
All of these

Question 22

The recognizing capability of NDFSM and DFSM

A.
May be different
B.
Must be same
C.
Must be different
D.
None of these

Question 23

Which of the following are not regular

A.
String of 0's whose length is a perfect square
B.
Set of all palindromes made up of 0's and 1's
C.
Strings of 0's, whose length is a prime number
D.
All of these

Question 24

Which of the following pairs of regular expressions are equivalent?

A.
$1(01)^*$ and $(10)^*$
B.
$y^+$ and $y^*y^+$
C.
$Y(yy)^*$ and $(yy)^*y$
D.
All of these

Question 25

The logic of pumping Lemma is a good example of

A.
The pigeon-hole principle
B.
The divide and conquer technique
C.
Recursion
D.
Iteration

Question 26

The FSM pictured shown in the figure

A.
Mealy machine
B.
Kleene machine
C.
Moore machine
D.
None of these

Question 27

The above machine

A.
Complements a given bit pattern
B.
Generates all strings of 0's and 1's
C.
Adds 1 to a given bit pattern
D.
None of these

Question 28

The language of all words with at least 2a's can be described by the regular expression

A.
$(a + b)^*a(a + b)^*a(a + b)^*$
B.
$b^*a^*b^*a(a + b)^*$
C.
$(a + b)^*ab^*a(a + b)^*$
D.
All of these

Question 29

For the following figure

A.
Complements a given bit pattern
B.
Finds 2's complement of a given bit pattern
C.
Increment a given bit pattern by 1
D.
Change the sign bit

Question 30

For which of the following applications regular expression can't be used?

A.
Designing compilers
B.
Simulating sequential circuits
C.
Developing text editors
D.
All of these

Question 31

The following CFG

S \rightarrow xS/yS/x/y

\ Is equivalent to the regular expression

A.
$(x + y)^*$
B.
$(x + y)^*(x + y)$
C.
$(x + y)(x + y)^*$
D.
All of these

Question 32

Any string of terminals that can be generated by the following CFG

S \rightarrow AB

\

A \rightarrow aA/bB/a

\

B \rightarrow Ba/Bb/a

A.
Has at least one b
B.
Has no consecutive a's or b's
C.
Should end in an 'a'
D.
Has at least two a's

Question 33

The following CFG

S \rightarrow aB/bA

\

A \rightarrow b/aS/bAA

\

B \rightarrow b/bs/aBB

\ Generates strings of terminals that have

A.
Equal number of a's and b's
B.
Odd number of a's and odd number of b's
C.
Even number of a's and number of b's
D.
Odd number a's and een number of a's

Question 34

The set

{a^n b^n / n = 1, 2, \ldots}

can be generated by a CFG

A.
$S \rightarrow ab/aSb$
B.
$S \rightarrow ab/aSb/\epsilon$
C.
$S \rightarrow aSbb/ab$
D.
$S \rightarrow aSbb/ab/aabb$

Question 35

Which of the following CFG's can't be simulated by an FSM?

A.
$S \rightarrow Sa/a$
B.
$S \rightarrow a/X, X \rightarrow cY, Y \rightarrow -d/aX$
C.
$S \rightarrow aSb/ab$
D.
None of these

Question 36

CFG is not closed under

A.
Union
B.
Complementation's
C.
Kleene star
D.
Product

Question 37

The set

A = {a^n b^n c^n / n = 1, 2, 3, \ldots}

is an example of a grammar that is

A.
Regular
B.
Not context free
C.
Context-free
D.
None of these

Question 38

Let

L_1 = {a^n b^n a^m / n, m = 1, 2, 3, \ldots}

\

L_2 = {a^n b^m a^m / n, m = 1, 2, 3, \ldots}

\

L_3 = {a^n b^n c^n / n = 1, 2, 3, \ldots}

\ Of the following the correct answer is

A.
$L_3 = L_1 \cap L_2$

Question 39

The intersection of a CFL, and a regular language

A.
Need not be regular
B.
Is always regular
C.
Need not be context free
D.
None of these

Question 40

A PDM behave lie an FSM when the number of auxiliary memory it has is

A.
0
B.
1
C.
2
D.
None of these

Question 41

CSG can be recognized by a

A.
FSM
B.
NDPDM
C.
DPDM
D.
Linearly bounded memory machine

Question 42

An FSM with

A.
A stack is more powerful than a FSM with no stack.
B.
2 stacks is more powerful than a FSM 1 stack
C.
Both (A) and (B) above
D.
None of these

Question 43

Recursive languages are

A.
Closed under intersection
B.
Closed under complementation
C.
Recursively enumerable
D.
All of these

Question 44

If

\omega \in (a, b)^*

satisfy

ab\omega = \omega ab

then

'\omega'

is

A.
Even
B.
Odd
C.
Null
D.
None of these

Question 45

Let

f : (a, b)^* \rightarrow (a, b)^*

be given by

f(n) = ax

for every value of

n \in {a, b}

then

f

is

A.
One to one not onto
B.
Not one to one and not onto
C.
One to one and onto
D.
Not one to one and onto

Question 46

Let if

G = ({S}, {a}, {S \rightarrow SS}, S)

, find language generated by

G

A.
$L(G) = \phi$
B.
$L(G) = a^*$

Question 47

What is the highest type number which can be applied to the following grammar

S \varphi \rightarrow Aa; A \rightarrow Ba, B \rightarrow abc

A.
Type0
B.
Type1
C.
Type2
D.
Type3

Question 48

Construct a grammar to generate

{(ab)^n / n \geq 1} \cup {(\text{ba})^n / n \geq 1}

A.
$S \rightarrow S_1, S_1 \rightarrow abS_1, S_1 \rightarrow ab, S \rightarrow S_2, S_2 \rightarrow baS_2, S_2 \rightarrow ba$

Question 49

Which string recognize it?

A.
$(a + b)^*$
B.
$a + b (a + bb)^* (a + (b + aa)^*)^*$
C.
$a^*b (b + aa)^*ba(b + aa)^*a$
D.
Information is not complete

Question 50

Regular expression corresponding to the state diagram given in below figure

A.
$(0 + 1 (1 + 01) '00)'$
B.
$(0 + 1 (1 + 10) 00)'$
C.
$(1 + 0)(0 + 10) '00)'$
D.
$(1 + 0 (1 + 00) 11)'$

Question 51

L = {a^p / p \text{ is a prime}}

is a

A.
Regular
B.
Accepted by DFA
C.
Not regular
D.
Accepted by PDA

Question 52

Regular expression corresponding to the automata given in figure below are:

A.
$1 (1 + 0 (0 + 10) '11)' 0 (0 + 10) '1$
B.
$0 (1 + 0 (1 + 01) '11)' 1 (1 + 10) '1$
C.
$1 (1 + 0 (1 + 01) '00)' 1 (1 + 01)'$
D.
$0 (1 + 0 (1 + 01) '00)' 1 (1 + 01)' 1$

Question 53

Grammar

S \rightarrow aAb, A \rightarrow aAb/a

is in

A.
LR(1) not in LR(0)
B.
LR(0) but not in LR(1)
C.
Both LR(0) and LR(1)
D.
Neither LR(0) nor in LR(1)

Question 54

The language

L = {a^n b^n c^n / n \geq 1}

is a

A.
Regular language
B.
Context-free language
C.
Context-sensitive language
D.
Recursively enumerable language

Question 55

The set

{a^n b^n / n = 1, 2, 3, \ldots}

can be generated by the CFG

A.
$S \rightarrow ab/aSb$
B.
$S \rightarrow ab/aSb/\epsilon$
C.
$S \rightarrow aaSbb/ab$
D.
None of these

Question 56

Which of the following CFG's can't be simulated by an FSM?

A.
$S \rightarrow Sa/a$
B.
$S \rightarrow abX, X \rightarrow cY, Y \rightarrow a/aX$
C.
$S \rightarrow aSb/ab$
D.
None of these

Question 57

The set

A = {a^n b^n c^n / n = 1, 2, 3, \ldots}

is an example of

A.
Regular language
B.
Non context free language
C.
Context free language
D.
None of these

Question 58

The intersection of CFL and a regular language

A.
Need not be regular
B.
Is always regular
C.
Need not be context free
D.
None of these

Question 59

Choose the correct statements:

A.
The power of DFSM and NDFSM are same.
B.
The power of DFSM and NDFSM are different.
C.
The power of DPDM and NDPDM are different.
D.
Both (A) and (C) above.

Question 60

Which of the following is accepted by an NDPDM but not by a DPDM?

A.
All strings in which a given symbol is present at least twice
B.
Even palindromes.
C.
Strings ending with a particular alphabet.
D.
None of these.

Practice another set Take a test on this chapter →

D.

2^x

B.

L_1

and

L_2

are not CFL, but

L_3

is CFL

C.

L_1

is a subset of

L_3

D.

None of these

C.

L(G) = a^n

D.

L(G) = a^n ba^n

B.

S \rightarrow S_1, S_1 \rightarrow aS_1, S_1 \rightarrow ab, S \rightarrow S_2, S_2 \rightarrow bS_2, S_2 \rightarrow bc

C.

S \rightarrow S_1, S_1 \rightarrow S_2, S_2 \rightarrow S_1a, S_1 \rightarrow ab, S_2 \rightarrow ba

D.

None of these