Here I am providing question paper for ONGC Graduate Trainee Exam (Computer Science discipline) for your reference:

ONGC Graduate Trainee Exam (Computer Science) Question Paper

Q.1.The order of an internal node in a B+ tree index is the maximum number of children it can have. Suppose that a child pointer takes 6 bytes, the search field value takes 14 bytes, and the block size is 512 bytes. What is the order of the internal node?
24
25
26
27

Q.2 The Boolean function x, y, + xy + x, y
x, + y,
x + y
x + y,
x, + y

Q.3.In an MxN matrix such that all non-zero entries are covered in a rows and b columns. Then the maximum number of non-zero entries, such that no two are on the same row or column, is
£ a + b
£ max {a, b}
£ min {M-a, N-b}
£ min {a, b}

Q.4.The relation scheme Student Performance (name, courseNo, rollNo, grade) has the following functional dependencies: The highest normal form of this relation scheme is
name, course No -> grade
roll No, course No -> grade
name -> roll No
rollNo -> name

Q.5.The minimum number of page frames that must be allocated to a running process in a virtual memory environment is determined by
the instruction set architecture
page size
physical memory size
number of processes in memory

Q.6.Let G be a simple graph with 20 vertices and 100 edges. The size of the minimum vertex cover of G is 8. Then, the size of the maximum independent set of G is
12
8
Less than 8
More than 12

Q.7.What does the following algorithm approximate? (Assume m > 1, Î > 0).
x = m;
y-i;
while (x - y > Î)
{ x = (x + y) / 2 ;
y = m/x ;
}
print (x) ;
log m
m2
m1/2
m1/3

Q.8.Consider the following C program
main ()
{ int x, y, m, n ;
scanf ("%d %d", &x, &y);
/ * Assume x > 0 and y > 0 * /
m = x; n = y ;
while ( m ! = n)
{ if (m > n)
m = m — n;
else
n = n - m ; }
printf("%d",n); }
The program computes
x + y, using repeated subtraction
x mod y using repeated subtraction
the greatest common divisor of x and y
the least common multiple of x and y

Q.9The best data structure to check whether an arithmetic expression has balanced parentheses is a
queue
stack
tree
list

Q.10.A Priority-Queue is implemented as a Max-Heap. Initially, it has 5 elements.The level-order traversal of the heap is given below: 10, 8,5,3,2 Two new elements 1 and 7 are inserted in the heap in that order. The level-order traversal of the heap after the insertion of the elements is
10,8,7,5,3,2,1
10,8,7,2,3,1,5
10,8,7,1,2,3,5
10,8,7,3,2,1,5

Q.11.An organization has a class B network and wishes to form subnets for 64 departments. The subnet mask would be
255.255.0.0
255.255.64.0
255.255.128.0
255.255.252.0

Q.12.Suppose the round trip propagation delay for a 10 Mbps Ethernet having 48-bit jamming signal is 46.4 ms. The minimum frame size is:
94
416
464
512

Q.13.The following numbers are inserted into an empty binary search tree in the given order: 10, 1, 3, 5, 15, 12, 16. What is the height of the binary search tree (the height is the maximum distance of a leaf node from the root)?
2
3
4
6

Q.14 Consider the following C function:
int f (int n)
{ static int i = 1;
if (n >= 5) return n;
n = n + i;
i ++;
return f (n);
}
The value returned by f(1) is
5
6
7
8

Q.15 The minimum number of page frames that must be allocated to a running process in a virtual memory environment is determined by
the instruction set architecture
page size
physical memory size
number of processes in memory

Q.16.The address resolution protocol (ARP) is used for
Finding the IP address from the DNS
Finding the IP address of the default gateway
Finding the IP address that corresponds to a MAC address
Finding the MAC address that corresponds to an IP address

Q.17. Consider the following relation schema pertaining to a students database:
Student (rollno, name, address)
Enroll (rollno, courseno, coursename)
where the primary keys are shown underlined. The number of tuples in the Student and Enroll tables are 120 and 8 respectively. What are the maximum and minimum number of tuples that can be present in (Student * Enroll), where ‘*’denotes natural join?
8, 8
120, 8
960, 8
960, 120

Q.18.Consider a direct mapped cache of size 32 KB with block size 32 bytes.The CPU generates 32 bit addresses. The number of bits needed for cache indexing and the number of tag bits are respectively
10, 17
10, 22
15, 17
5, 17

Q.19.The goal of structured programming is to
have well indented programs
be able to infer the flow of control from the compiled code
be able to infer the flow of control from the program text
avoid the use of GOTO statements

Q.20.The tightest lower bound on the number of comparisons in the worst ease,for comparison- based sorting is of the order of
n
n 2
n log n
n log2 n

Q.21.Let G be a simple graph with 20 vertices and 100 edges.The size of the minimum vertex cover of G is 8. Then, the size of the maximum independent set of G is
12
8
Less than 8
More than 12

Q.22.A and B are the only two stations on an Ethernet.Each has a steady queue of frames to send. Both A and B attempt to transmit a frame, collide, and A wins the first backoff race. At the end of this successful transmission by A, both A and B attempt to transmit and collide. The probability that A wins the second back-off race is
0.5
0.625
0.75
1.0

Q.23.Let A be a sequence of 8 distinct integers sorted in ascending order.How many distinct pairs of sequences, B and C are there such that (i) each is sorted in ascending order, (ii) B has 5 and C has 3 elements, and (iii) the result of merging B and C gives A?
2
30
56
256

Q.24.In a network of LANs connected by bridges,packets are sent from one LAN to another through intermediate bridges. Since more than one path may exist between two LANs, packets may have to be routed through multiple bridges.Why is the spanning tree algorithm used for bridge-routing?
For shortest path routing between LANs
For avoiding loops in the routing paths
For fault tolerance
For minimizing collisions

Q.25.A Priority-Queue is implemented as a Max-Heap.Initially,it has 5 elements.The level-order traversal of the heap is given below: 10, 8,5,3,2 Two new elements 1 and 7 are inserted in the heap in that order. The level-order traversal of the heap after the insertion of the elements is
10,8,7,5,3,2,1
10,8,7,2,3,1,5
10,8,7,1,2,3,5
10,8,7,3,2,1,5

Q.26.An organization has a class B network and wishes to form subnets for 64 departments. The subnet mask would be
255.255.0.0
255.255.64.0
255.255.128.0
255.255.252.0

Q.27.Suppose the round trip propagation delay for a 10 Mbps Ethernet having 48-bit jamming signal is 46.4 ms. The minimum frame size is:
94
416
464
512

Q.28.The problems 3-SAT and 2-SAT are
both in P
both NP-complete
NP-complete and in P respectively
undecidable and NP-complete respectively

Q.29.Consider the following relation schema pertaining to a students database:
Student (rollno, name, address)
Enroll (rollno, courseno, coursename)
where the primary keys are shown underlined. The number of tuples in the Student and Enroll tables are 120 and 8 respectively. What are the maximum and minimum number of tuples that can be present in (Student * Enroll), where ‘*’denotes natural join?
8, 8
120, 8
960, 8
960, 120

Q.30.Consider a relation scheme R = (A, B, C, D, E, H) on which the following functional dependencies hold : (A -> B, BC -> D, E -> C, D -> A). What are the candidate keys of R?
AE, BE
AE, BE, DE
AEH, BEH, BCH
AEH, BEH, DEH

Q.31.The goal of structured programming is to
have well indented programs
be able to infer the flow of control from the compiled code
be able to infer the flow of control from the program text
avoid the use of GOTO statements

Q.32.A circuit outputs a digit in the form of 4 bits. 0 is represented by 0000,1 by 0001,..., 9 by 1001. A combinational circuit is to be designed which takes these 4 bits as input and outputs 1 if the digit ³ 5, and 0 otherwise. If only AND, OR and NOT gates may be used, what is the minimum number of gates required
2
3
4
5

Q.33.If 73x (in base-x number system) is equal to 54y (in base-y number system), the possible values of x and y are
8, 16
10, 12
9, 13
8, 11

Q.34.In a packet switching network,packets are routed from source to destination along a single path having two intermediate nodes. If the message size is 24 bytes and each packet contains a header of 3 bytes, then the optimum packet size is
4
6
7
9

Q.35.Consider an operating system capable of loading and executing a single sequential user process at a time. The disk head scheduling algorithm used is First Come First Served (FCFS). If FCFS is replaced by Shortest Seek Time First (SSTF), claimed by the vendor to give 50% better benchmark results, what is the expected improvement in the I/O performance of user programs ?
50%
40%
25%
0%

Q.36.How many distinct binary search trees can be created out of 4 distinct keys?
5
14
24
42