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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 2

50 questions

Question 1

Let

L

be set of strings from alphabet. The Kleen closure of

L

is given as

A.
$L' = \bigcup_{i=0} L^i$

50

B.

L^+ = \bigcup_{i=1} L^i

C.

L' = \bigcup_{i=0} L^i

D.

L^+ = \bigcup_{i=1} L^i

Question 2

If a source language supports some macro pre-processor functions then these functions can be implemented in

A.
Lexical analysis phase
B.
Code generation
C.
Parsing
D.
Syntax analysis phase

Question 3

If

e1

and

e2

are the regular expressions denoting the language

L1

and

L2

respectively, then which of the following is wrong?

A.
${e_1} + {e_2}$ is regular expression denoting $L1 \cup L2$

Question 4

The regular expression

(a + b)^*

denotes all strings

A.
With zero or more instances of $a$ and $b$ both simultaneously
B.
With one or more instances of $a$ and $b$
C.
Equal to regular expression $(a^* + b)^*$
D.
Any combination of $a$ 's and $b$ 's including null string

Question 5

Every CFG can be transferred into equivalent

A.
Greiback normal form
B.
Either (a) or (b)
C.
CNF
D.
All of the above

Question 6

Consider the following regular expression

R = (ab + abb)^*

\ Which of the following is not in

R

?

A.
Ababab
B.
Abbab
C.
Abababbbab
D.
Abbabbbab

Question 7

In the figure shown, a DFA

m

has start state

A

and accepting state

D

. Which of the following regular expression denoted the set of all words accepted by

m

?

A.
001
B.
$(0 + 1)^* 011$
C.
$10^* 1^* 0$
D.
$1^* 0^* 001$

Question 8

Which of the following is most general phase-structured grammar?

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

Question 9

Context-free grammar can be recognized by

A.
Finite state automation
B.
2-way linear bounded automata
C.
Push down automata
D.
Both (B) and (C) above

Question 10

Context sensitive grammar (CSG) can be recognized by

A.
Finite state automata
B.
Push down automata
C.
2-way linear bounded automata
D.
None of these

Question 11

Consider the grammar

G

, where the productions are numbered as shown 1.

E \rightarrow E + T

2.

E \rightarrow T

3.

T \rightarrow T^* F

4.

T \rightarrow F

5.

F \rightarrow e

6.

F \rightarrow a

If a shift-reduce (bottom-up) parser writes the production number used immediately after performing any reduction, what will be printed if the parser input is

a + a * a

?

A.
62461
B.
6262441
C.
64642331
D.
64264631

Question 12

Which sentence can be generated by

S \rightarrow As/bA

\

A \rightarrow d/ccA

A.
Becddd
B.
abbbd
C.
aabccd
D.
ababccd

Question 13

Which of the following recognizes variables prefixes of the grammar?

A.
DFA
B.
NFA
C.
Both errors can be detected
D.
None of these

Question 14

Dynamic errors can be detected

A.
Only at compile time
B.
Only at run time
C.
Both at compile time and at run time
D.
None of these

Question 15

Compiler is a software which converts

A.
High level language program into low level language program
B.
Source program into object program
C.
Program in high level language into program in low level language
D.
Program in source language into program in object language

Question 16

The language

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

.

A.
Is a context free
B.
Both (a) and (b)
C.
Is not context free
D.
None of these

Question 17

The language

L = {0n 1n 2n \text{ where } n > 0}

is a

A.
CFL
B.
Context-sensitive language
C.
Regular language
D.
Recursive enumerable language

Question 18

Which of the choice in an operator grammar equivalent for

S \rightarrow SAS/a

\

A \rightarrow bSb/b

\ Assume

S

is start symbol

A.
$S \rightarrow SAS/a, A \rightarrow bSb/b$
B.
$S \rightarrow SbAbS/a, A \rightarrow b$

Question 19

Let

S

and

T

be language over

\Sigma = {a, b}

represent by regular expression

(a + b^*) *

and

(a + b)^*

respectively then

A.
$S \subset T$
B.
$T \subset S$
C.
$S = T$

Question 20

Let

L

denote the language generated by the grammar

S \rightarrow 050100

then

A.
$L = 0^*$
B.
$L$ is regular but not $0^*$
C.
$L$ is context free but not regular
D.
$L$ is not context free

Question 21

Consider the regular expression

(0 + 1) (0 + 1)^*

......n times. The minimum state finite automation that recognizes the language represented by this regular expression contains

A.
$n$ states
B.
$n + 2$ states
C.
$n + 1$ states
D.
None of these

Question 22

A grammar that is both left and right recursive for non-terminal is

A.
Ambiguous
B.
Information is not sufficient
C.
Unambiguous
D.
None of these

Question 23

If the regular set

A

is represented by

A = (01 + 1)^*

and the regular set

B

represented by

B = [(01)^* 1^*]

then

A.
$A \subset B$
B.
$A$ and $B$ are uncomparable
C.
$B \subset A$

Question 24

Which of the following can be recognized by a DFA

A.
The number 1, 2, 4 ...... $x^n$ ......written in binary
B.
The number 1, 2, 4, ...... $x^n$ ......written in un binary
C.
The set of binary strings in which the number of zeros is the same as the number of ones
D.
The set ${1, 101, 11011, 1110111 ...}$

Question 25

The string 1101 does not belong to the set represented by

A.
$110'(0+1)$
B.
$(10)^* (01)^* (00 + 11)^*$
C.
$1(0 + 1)^* 101$
D.
$[00+(11)^* 0]$

Question 26

Regarding the power of recognition of language, which of the following statements is false?

A.
The NDFA is equivalent to DFA
B.
NPDA is equivalent to DPDA
C.
Non-deterministic Turing machines are equivalent to deterministic push-down automata
D.
Multi-tape Turing-machine are equivalent to Single-Tape Turing machine

Question 27

Let

*

be defined as

a * b = a + y

. Let

c = a * b

; value of

c * a

is

A.
$a + b$
B.
$a$
C.
$0$
D.

Question 28

Which one of the following regular expressions over

{0, 1}

denotes the set of all string not containing 100 as a substring?

A.
$0' (1 + 0)$
B.
$1' 01$
C.
$0' 1010$
D.
$0' (10 + 1)$

Question 29

Which of the following languages over

{a, b, c}

is accepted by deterministic push down automata?

A.
${\omega \subset \omega^b / \omega \in (a, b)}$
B.
${\omega \omega^b / \omega \in {a, b, c}}$
C.
${a^b c^m / n \geq 0}$
D.
${\omega / \omega \text{ is palindrome } {a, b, c}}$

Question 30

Two of following four regular expressions are equivalent, which two?

A.
$(00)^* (\epsilon + 0)$
B.
$(00)^*$
C.
$0^*$
D.
$0(00)^*$

Question 31

The major difference between a Moore and Mealy machine is that

A.
The output of the former depends only on the present state and present input
B.
The output of the former depends only on the present state
C.
The output of the former depends only on the present input
D.
All of these

Question 32

Finite state machine can recognize

A.
Any grammar
B.
Any unambiguous grammar
C.
Only CG
D.
Only regular grammar

Question 33

Pumping Lemma is generally used for proving

A.
A given grammar is regular
B.
A given grammar is not regular
C.
Whether two given regular expressions are equivalent or not
D.
None of these

Question 34

Which of the following is not regular?

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

Question 35

Choose the correct statements

A.
$A = {a^n b^n / n = 0, 1, 2, 3, \ldots}$ is regular language
B.
The set $B$ of all strings of equal number of $a$ 's and $b$ 's defines a regular language
C.
$L(A^* B^*) \cap B$ gives the set $A$
D.
None of these

Question 36

The basic limitations of finite state machine is that

A.
It cannot remember arbitrary large amount of information
B.
It cannot recognize grammars are regular
C.
It sometimes recognize grammars are not regular
D.
All of these

Question 37

Palindrome cannot be recognized by any FSM because

A.
An FSM can't remember arbitrary information
B.
An FSM can't deterministically fix the mid point
C.
Both (A) and (B)
D.
None of these

Question 38

An FSM can be considered to be a TM (Turing machine)

A.
Of finite tape length, rewinding capability and unidirectional tape movement
B.
Of finite tape length, without rewinding and unidirectional tape movement
C.
Of finite tape length, rewinding capability and bidirectional tape movement
D.
All of these

Question 39

Turing machine is more powerful than FSM because

A.
Tape movement is confined to one direction
B.
It has no finite state control
C.
It has the capability to remember arbitrary long sequence of input symbols
D.
None of these

Question 40

For given picture the FSM recognizes

A.
All strings
B.
$\epsilon$ -alone
C.
No strings
D.
None of these

Question 41

In given picture, the FSM represents

A.
Mealy machine
B.
Kleen machine
C.
Moore machine
D.
All of these

Question 42

The language of all words with at least

2a

's can be described by the regular expression:

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

Question 43

Which of the following pairs of regular expressions are not equivalent?

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

Question 44

Any given transition graph has an equivalent

A.
Regular expression
B.
NDFSM
C.
DFSM
D.
All of these

Question 45

The following CFG

S \rightarrow aS/bS/a/b

is equivalent to regular expression

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

Question 46

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

S \rightarrow XY

\

X \rightarrow ax/bx/a

\

Y \rightarrow Ya/Yb/a

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

Question 47

The following CFG

S \rightarrow aB/Ba

\

A \rightarrow b/aS/Baa

\

B \rightarrow a/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

Question 48

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 49

Choose the correct statement

A.
All language can be generated CFG
B.
Any regular language has an equivalent CFG
C.
Some non-regular languages can't be generated by an CFG
D.
Some regular language can't be simulated by an FSM

Question 50

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

Practice another set Take a test on this chapter →

B.

e2 e3

regular expression denoting

L1L2

C.

\emptyset

is not regular expression

D.

{e_1}^*

is regular expression denoting

L^*

C.

S \rightarrow SbSbS/SbS/a

D.

S \rightarrow SbS/b

D.

S \cap T = 0

D.

A = B

1

's

C.

Even number of

a

's and even number of

a

's

D.

Odd number of

a

's and even number of

a

's