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.

Monday, 25 September 2017

1.       The advantages of integrated circuits over a discrete device circuit due to their following characteristics:
(A) Smaller size
(B) Lower cost
(C) Higher reliability
(D) All of the above
Answer: D
2.       The cyclic codes are used when it is required for :
(A) Data transfer
(B) Arithmetic and logical computation
(C) Continuously varying signal representation
(D) Counting the number of bits
Answer: C
3.       A microprocessor with 12 address lines is capable of addressing up to :
(A) 4096 Locations
(B) 1024 Locations
(C) 64K Locations
(D) 2048 Locations
Answer: A
4.       When the RESET is performed in Intel 8085 microprocessor, the first operation is :
(A) Stock initialization
(B) Instruction fetch from the location 2000H
(C) Instruction fetch from the location 0000H
(D) Memory read from location 0000H
Answer: C
5.       The overflow flag is set in 8086 microprocessor when ..............
(A) The sum is more than 16 bits
(B) Carry and sign flags are set
(C) Signed number go out of their range after arithmetic operation
(D) None of the above
Answer: C
6.       One of the following is data security threat :
(A) updation or deletion of data
(B) fraudulent manipulation of data
(C) hardware failure
(D) privacy invasion
Answer: B, D
7.       Consider the situation that the transaction 'P' holds shared key lock X. Also, other transaction 'Q' requests for shared key lock X, then :
(A) request will be immediately granted
(B) the deadlock situation is created
(C) request will be rejected after some time
(D) request will be granted at it is released by P.
Answer: A
8.       In an oracle, which trigger type would be fired during instance start-up :
(A) database event
(B) user event
(C) file event
(D) record event
Answer: A
9.       The component of the oracle that contains the memory structure and background process :
(A) database
(B) database file
(C) instance
(D) log file
Answer: C
10.    The redo log files are used for :
(A) shut down
(B) instance recovery
(C) archiving
(D) instance start up
Answer: B

Sunday, 24 September 2017

261.       The largest element of an array index is called its .................
(A) lower bound.
(B) range.
(C) upper bound.
(D) All of these.
Answer: C
262.       What is the result of the following operation:
Top (Push (S, X))
(A) X
(B) null
(C) S
(D) None of these.
Answer: A
263.       How many nodes in a tree have no ancestors?
(A) 0
(B) 1
(C) 2
(D) n
Answer: B
264.       In order traversal of binary search tree will produce ................
(A) unsorted list
(B) reverse of input
(C) sorted list
(D) none of the above
Answer: C
265.       In binary heap, whenever the root is removed then the rightmost element of last level is replaced by the root. Why?
(A) It is the easiest possible way.
(B) To make sure that it is still complete binary tree.
(C) Because left and right subtree might be missing.
(D) None of these
Answer: B
266.       In order to get the contents of a Binary search tree in ascending order, one has to traverse it in ............
(A) pre-order
(B) in-order
(C) post order
(D) not possible
Answer: B
267.       Which of the following sorting algorithm is stable?
(A) Insertion sort
(B) Bubble sort
(C) Quick sort
(D) Heap sort
Answer: D
268.       The prefix form of an infix expression p + q − r * t is:
(A) + pq − *rt
(B) − +pqr * t
(C) − +pq * rt
(D) − + * pqrt
Answer: C
269.       Which data structure is used for implementing recursion?
(A) Queue
(B) Stack
(C) Arrays
(D) List
Answer: B
270.    In binary search, average number of comparison required for searching an element in a list if n numbers is:
(A) log2 n
(B) n / 2
(C) n
(D) n – 1
Answer: A

Saturday, 23 September 2017

251.       In general, linked lists allow:
(A) Insertions and removals anywhere.
(B) Insertions and removals only at one end.
(C) Insertions at the back and removals from the front.
(D) None of the above.
Answer: A
252.       Which of the following has search efficiency of Ο(1)?
(A) Tree
(B) Heap
(C) Hash Table
(D) Linked-List
Answer: C
253.       Which of the following operations is performed more efficiently by doubly linked list than by singly linked list?
(A) Deleting a node whose location in given
(B) Searching of an unsorted list for a given item
(C) Inverting a node after the node with given location
(D) Traversing a list to process each node
Answer: A
254.       The extra key inserted at the end of the array is called a, ................
(A) End key.
(B) Stop key.
(C) Sentinel.
(D) Transposition.
Answer: C
255.       The prefix form of A-B/ (C * D ^ E) is:
(A) -/*^ACBDE
(C) -A/B*C^DE
(D) -A/BC*^DE
Answer: C
256.       Maximum number of nodes in a binary tree with height k, root is at height 0, is:
(A) 2k − 1
(B) 2k+1 − 1
(C) 2k-1 + 1
(D) 2k + 1
Answer: B
257.       Consider that n elements are to be sorted. What is the worst case time complexity of Bubble sort?
(A) O(1)
(B) O(log2n)
(C) O(n)
(D) O(n2)
Answer: D
258.       Time complexity of Depth First Traversal of is ..................
(A) Θ(|V|+|E|)
(B) Θ(|V|)
(C) Θ(|E|)
(D) Θ(|V|*|E|)
Answer: A
259.       A characteristic of the data that binary search uses but the linear search ignores is
the ..................
(A) Order of the elements of the list.
(B) Length of the list.
(C) Maximum value in list.
(D) Type of elements of the list.
Answer: A
260.    In Breadth First Search of Graph, which of the following data structure is used?
(A) Stack
(B) Queue
(C) Linked List
(D) None of the above
Answer: B

Friday, 22 September 2017

241.       An ADT is defined to be a mathematical model of a user-defined type along with the collection of all ................ operations on that model.
(A) Cardinality
(B) Assignment
(C) Primitive
(D) Structured
Answer: C
242.       An algorithm is made up of two independent time complexities f (n) and g (n). Then the complexities of the algorithm is in the order of
(A) f(n) x g(n)
(B) Max ( f(n),g(n))
(C) Min (f(n),g(n))
(D) f(n) + g(n)
Answer: B
243.       The goal of hashing is to produce a search that takes .............
(A) O(1) time
(B) O(n2) time
(C) O(log n) time
(D) O(n log n) time
Answer: A
244.       The best average behaviour is shown by:
(A) Quick Sort
(B) Merge Sort
(C) Insertion Sort
(D) Heap Sort
Answer: A
245.       What is the postfix form of the following prefix *+ab–cd
(A) ab+cd–*
(B) abc+*–
(C) ab+*cd–
(D) ab+*cd–
Answer: A
246.       Time complexities of three algorithms are given. Which should execute the slowest for large values of N?
(A) O(N1/2)
(B) O(N)
(C) O(log N)
(D) None of these
Answer: B
247.       What data structure is used for depth first traversal of a graph?
(A) Queue
(B) Stack
(C) List
(D) None of these
Answer: B
248.       A queue is a,
(A) FIFO (First In First Out) list.
(B) LIFO (Last In First Out) list.
(C) Ordered array.
(D) Linear tree.
Answer: A
249.       Time required to merge two sorted lists of size m and n, is ............
(A) Ο(m | n)
(B) Ο(m + n)
(C) Ο(m log n)
(D) Ο(n log m)
Answer: B
250.    Which data structure is needed to convert infix notation to postfix notation?
(A) Branch
(B) Queue
(C) Tree
(D) Stack
Answer: D

Thursday, 21 September 2017

231.       Let the following circular queue can accommodate maximum six elements with the
following data
front = 2             rear = 4
queue = .........; L, M, N, ...., ....
What will happen after ADD O operation takes place?
(A) front = 2       rear = 5
queue = ..........; L, M, N, O, .........
(B) front = 3       rear = 5
queue = L, M, N, O, .........
(C) front = 3      rear = 4
queue = .........; L, M, N, O, .........
(D) front = 2      rear = 4
queue = L, M, N, O, .........
Answer: A
232.       A binary tree of depth “d” is an almost complete binary tree if:
(A) Each leaf in the tree is either at level “d” or at level “d–1”
(B) For any node “n” in the tree with a right descendent at level “d” all the left descendents of “n” that are leaves, are also at level “d”
(C) Both (A) & (B)
(D) None of the above
Answer: C
233.       A linear collection of data elements where the linear node is given by means of pointer is called ...............
(A) Linked list
(B) Node list
(C) Primitive list
(D) None of these
Answer: A
234.       Representation of data structure in memory is known as:
(A) recursive
(B) abstract data type
(C) storage structure
(D) file structure
Answer: B
235.       If the address of A[1][1] and A[2][1] are 1000 and 1010 respectively and each element
occupies 2 bytes then the array has been stored in ............... order.
(A) row major
(B) column major
(C) matrix major
(D) none of these
Answer: A
236.       What data structure can be used to check if syntax has balanced parenthesis?
(A) Queue
(B) Tree
(C) List
(D) Stack
Answer: D
237.       How many binary trees with 3 nodes which when traversed in post order gives the sequence A, B, C is ?
(A) 3
(B) 4
(C) 5
(D) 6
Answer: C
238.       An adjacency matrix representation of a graph cannot contain information of :
(A) nodes
(B) edges
(C) direction of edges
(D) parallel edges
Answer: D
239.       Which data structure represents a waiting line and limits insertions to be made at the back of the data structure and limits removals to be made from the front?
(A) Stack
(B) Queue
(C) Binary tree
(D) Linked list
Answer: B
240.    Quick sort is also known as .............
(A) Merge sort
(B) Heap sort
(C) Bubble sort
(D) None of these
Answer: D