Computer Science Study Materials for Competitive Exams

Sample Questions, Previous Year Solved Papers, Study Materials For Competitive Examinations Like UGC NET, SET And GATE Computer Science.

Wednesday, 6 June 2018

71.       A network on the Internet has a subnet mask of What is the maximum number of hosts it can handle?
(A) 1024
(B) 2048
(C) 4096
(D) 8192
Answer: C
72.       Four bits are used for packed sequence numbering in a sliding window protocol used in a computer network. What is the maximum window size?
(A) 4
(B) 8
(C) 15
(D) 16
Answer: C
73.       Given the following two grammars :
G1 : S ® AB | aaB
A ® a | Aa
B ® b
G2 : S ® a S b S | b S a S | l
Which statement is correct?
(A) G1 is unambiguous and G2 is unambiguous.
(B) G1 is unambiguous and G2 is ambiguous.
(C) G1 is ambiguous and G2 is unambiguous.
(D) G1 is ambiguous and G2 is ambiguous.
Answer: D
74.       Match the following :
List – I
a. Chomsky Normal form
b. Greibach Normal form
c. S-grammar
d. LL grammar
List – II
i. S ® b S S | a S | c
ii. S ® a S b | ab
iii. S ® AS | a
A ® SA | b
iv. S ® a B S B
B ® b
Codes :
      a    b    c   d
(A) iv   iii    i    ii
(B) iv   iii    ii   i
(C) iii   iv    i    ii
(D) iii   iv    ii   i
Answer: C
75.       Given the following two languages :
L1 = {anbn | n ≥ 1} È {a}
L2 = {w C wR | w Î {a, b}*}
Which statement is correct?
(A) Both L1 and L2 are not deterministic.
(B) L1 is not deterministic and L2 is deterministic.
(C) L1 is deterministic and L2 is not deterministic.
(D) Both L1 and L2 are deterministic.
Answer: D

Tuesday, 5 June 2018

61.       Given the following equalities :
E1 : nK+Î + nK lg n = q(nK+Î) for all fixed K and Î, K > 0 and Î > 0.
E2 : n32n + 6n23n = O(n32n)
Which of the following is true?
(A) E1 is correct and E2 is correct.
(B) E1 is correct and E2 is not correct.
(C) E1 is not correct and E2 is correct.
(D) E1 is not correct and E2 is not correct.
Answer: B
62.       Consider the fractional knapsack instance n = 4, (p1, p2, p3, p4) = (10, 10, 12, 18), (w1, w2, w3, w4) = (2, 4, 6, 9) and M = 15. The maximum profit is given by
(Assume p and w denotes profit and weight of objects respectively)
(A) 40
(B) 38
(C) 32
(D) 30
Answer: B
63.       The solution of the recurrence relation of
(A) O(n2)
(B) O(nlg n)
(C) O(n)
(D) O(l g n)
Answer: C
64.       If h is chosen from a universal collection of hash functions and is used to hash n keys into a table of size m, where n ≤ m, the expected number of collisions involving a particular key K is
(A) less than 1
(B) less than lg n
(C) greater than 1
(D) greater than lg n
Answer: A
65.       Given the following statements :
S1 : The subgraph-isomorphism problem takes two graphs G1 and G2 and asks whether G1 is a subgraph of G2.
S2 : The set-partition problem takes as input a set S of numbers and asks whether the numbers can be partitioned into two sets A
Which of the following is true?
(A) S1 is NP problem and S2 is P problem.
(B) S1 is NP problem and S2 is NP problem.
(C) S1 is P problem and S2 is P problem.
(D) S1 is P problem and S2 is NP problem.
Answer: B
66.       Suppose that the splits at every level of quicksort are in the proportion (1 – a) to a, where 0 < a ≤ ½ is a constant. The minimum depth of a leaf in the recursion tree is approximately given by
Answer: C
67.       Ten signals, each requiring 3000 Hz, are multiplexed on to a single channel using FDM. How much minimum bandwidth is required for the multiplexed channel? Assume that the guard bands are 300 Hz wide.
(A) 30,000
(B) 32,700
(C) 33,000
(D) None of the above
Answer: B
68.       A terminal multiplexer has six 1200 bps terminals and ‘n’ 300 bps terminals connected to it. If the outgoing line is 9600 bps, what is the value of n?
(A) 4
(B) 8
(C) 16
(D) 28
Answer: B
69.       Which of the following is used in the options field of IPv4?
(A) Strict source routing
(B) Loose source routing
(C) time stamp
(D) All of the above
Answer: D
70.    Which layers of the OSI reference model are host-to-host layers?
(A) Transport, Session, Presentation, Application
(B) Network, Transport, Session, Presentation
(C) Data-link, Network, Transport, Session
(D) Physical, Data-link, Network, Transport
Answer: A

Monday, 4 June 2018

51.       The pure object oriented programming language with extensive metadata available and modifiable at run time is
(A) Small talk
(B) C++
(C) Java
(D) Eiffel
Answer: A
52.       Match the following interfaces of Java. Servlet package :
List – I
a. Servlet Config
b. Servlet Context
c. Servlet Request
d. Servlet Response
List – II
i. Enables Servlets to log events
ii. Read data from a client
iii. Write data to a client
iv. To get initialization parameters
Codes :
      a    b    c    d
(A) iii    iv   ii     i
(B) iii    ii    iv    i
(C) ii    iii    iv    i
(D) iv    i    ii    iii
Answer: D
53.       The syntax of capturing events method for document object is
(A) CaptureEvents()
(B) CaptureEvents(Orgs eventType)
(C) CaptureEvents(eventType)
(D) CaptureEvents(eventVal)
Answer: C
54.       Linking to another place in the same or another webpage require two A (Anchor) tags, the first with the ................. attribute and the second with the ................ attribute.
Answer: C
55.       Given an image of size 1024 × 1024 pixels in which intensity of each pixel is an 8-bit quality. It requires ............... of storage space if the image is not compressed.
(A) one Terabyte
(B) one Megabyte
(C) 8 Megabytes
(D) 8 Terabytes
Answer: B
56.       Match the following cryptographic algorithms with their design issues :
List – I      List – II
a. DES      i. Message Digest
b. AES      ii. Public Key
c. RSA      iii. 56-bit key
d. SHA-1   iv. 128-bit key
Codes :
      a    b    c    d
(A) ii     i    iv    iii
(B) iii    i    iv    ii
(C) iii    iv   ii    i
(D) iv    i    ii    iii
Answer: C
57.       Consider a code with five valid code words of length ten :
0000000000, 0000011111, 1111100000, 1110000011, 1111111111
Hamming distance of the code is
(A) 5
(B) 10
(C) 8
(D) 9
Answer: Marks to all
58.       Which of the following special cases does not require reformulation of the problem in order to obtain a solution?
(A) Alternate optimality
(B) Infeasibility
(C) Unboundedness  
(D) All of the above
Answer: A
59.       The given maximization assignment problem can be converted into a minimization problem by
(A) subtracting each entry in a column from the maximum value in that column.
(B) subtracting each entry in the table from the maximum value in that table.
(C) adding each entry in a column from the maximum value in that column.
(D) adding maximum value of the table to each entry in the table.
Answer: B
60.    The initial basic feasible solution of the following transportion problem :
then the minimum cost is
(A) 76
(B) 78
(C) 80
(D) 82
Answer: A