GATE CS 2025: Computer Science and Information Technology Session 1
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Computer Science and Information Technology (CS1)
General Aptitude
Q.1 – Q.5 Carry ONE mark Each
Q.1 Ravi had ______ younger brother who taught at ______ university. He was widely
regarded as ______ honorable man.
Select the option with the correct sequence of articles to fill in the blanks.
(A) a; a; an
(B) the; an; a
(C) a; an; a
(D) an; an; a
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Computer Science and Information Technology (CS1)
Q.2 The CEO’s decision to downsize the workforce was considered myopic because it
sacrificed long-term stability to accommodate short-term gains.
Select the most appropriate option that can replace the word “myopic” without
changing the meaning of the sentence.
(A) visionary
(B) shortsighted
(C) progressive
(D) innovative
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Computer Science and Information Technology (CS1)
Q.3 The average marks obtained by a class in an examination were calculated as 30.8.
However, while checking the marks entered, the teacher found that the marks of one
student were entered incorrectly as 24 instead of 42. After correcting the marks, the
average becomes 31.4. How many students does the class have?
(A) 25
(B) 28
(C) 30
(D) 32
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Computer Science and Information Technology (CS1)
Q.4 Consider the relationships among P, Q, R, S, and T:
• P is the brother of Q.
• S is the daughter of Q.
• T is the sister of S.
• R is the mother of Q.
The following statements are made based on the relationships given above.
(1) R is the grandmother of S.
(2) P is the uncle of S and T.
(3) R has only one son.
(4) Q has only one daughter.
Which one of the following options is correct?
(A) Both (1) and (2) are true.
(B) Both (1) and (3) are true.
(C) Only (3) is true.
(D) Only (4) is true.
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Computer Science and Information Technology (CS1)
Q.5 According to the map shown in the figure, which one of the following statements is
correct?
Note: The figure shown is representative.
1st Main Road
Library Canteen
Physics Lab Hospital
5th Cross Road
Hostels Chemistry
Lab
N
Classrooms
W E
S
(A) The library is located to the northwest of the canteen.
(B) The hospital is located to the east of the chemistry lab.
(C) The chemistry lab is to the southeast of physics lab.
(D) The classrooms and canteen are next to each other.
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Computer Science and Information Technology (CS1)
Q.6 – Q.10 Carry TWO marks Each
Q.6 “I put the brown paper in my pocket along with the chalks, and possibly other things.
I suppose every one must have reflected how primeval and how poetical are the
things that one carries in one’s pocket: the pocket-knife, for instance the type of all
human tools, the infant of the sword. Once I planned to write a book of poems
entirely about the things in my pocket. But I found it would be too long: and the age
of the great epics is past.”
(From G.K. Chesterton’s “A Piece of Chalk”)
Based only on the information provided in the above passage, which one of the
following statements is true?
(A) The author of the passage carries a mirror in his pocket to reflect upon things.
(B) The author of the passage had decided to write a poem on epics.
(C) The pocket-knife is described as the infant of the sword.
(D) Epics are described as too inconvenient to write.
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Computer Science and Information Technology (CS1)
Q.7 In the diagram, the lines QR and ST are parallel to each other. The shortest distance
between these two lines is half the shortest distance between the point P and line
QR. What is the ratio of the area of the triangle PST to the area of the trapezium
SQRT?
Note: The figure shown is representative.
P
S T
Q R
(A) 1
3
(B) 1
4
(C) 2
5
(D) 1
2
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Computer Science and Information Technology (CS1)
Q.8 A fair six-faced dice, with the faces labelled ‘1’, ‘2’, ‘3’, ‘4’, ‘5’, and ‘6’, is rolled
thrice. What is the probability of rolling ‘6’ exactly once?
(A) 75
216
(B) 1
6
(C) 1
18
(D) 25
216
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Computer Science and Information Technology (CS1)
Q.9 A square paper, shown in figure (I), is folded along the dotted lines as shown in the
figures (II) and (III). Then a few cuts are made as shown in figure (IV). Which one
of the following patterns will be obtained when the paper is unfolded?
Note: The figures shown are representative.
(I) (II) (III) (IV)
(A)
(B)
(C)
(D)
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Computer Science and Information Technology (CS1)
Q.10 A shop has 4 distinct flavors of ice-cream. One can purchase any number of scoops
of any flavor. The order in which the scoops are purchased is inconsequential.
If one wants to purchase 3 scoops of ice-cream, in how many ways can one make
that purchase?
(A) 4
(B) 20
(C) 24
(D) 48
Q.11 – Q.35 Carry ONE mark Each
Q.11 Suppose a program is running on a non-pipelined single processor computer system.
The computer is connected to an external device that can interrupt the processor
asynchronously. The processor needs to execute the interrupt service routine (ISR)
to serve this interrupt. The following steps (not necessarily in order) are taken by
the processor when the interrupt arrives:
(i) The processor saves the content of the program counter.
(ii) The program counter is loaded with the start address of the ISR.
(iii) The processor finishes the present instruction.
Which ONE of the following is the CORRECT sequence of steps?
(A) (iii), (i), (ii)
(B) (i), (iii), (ii)
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Computer Science and Information Technology (CS1) (C) (i), (ii), (iii) (D) (iii), (ii), (i) Organising Institute: IIT Roorkee Page 11 of 64
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Computer Science and Information Technology (CS1) Q.12 Which ONE of the following statements is FALSE regarding the symbol table? (A) Symbol table is responsible for keeping track of the scope of variables. (B) Symbol table can be implemented using a binary search tree. (C) Symbol table is not required after the parsing phase. (D) Symbol table is created during the lexical analysis phase. Organising Institute: IIT Roorkee Page 12 of 64
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Computer Science and Information Technology (CS1)
Q.13 Which ONE of the following techniques used in compiler code optimization uses
live variable analysis?
(A) Run-time function call management
(B) Register assignment to variables
(C) Strength reduction
(D) Constant folding
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Computer Science and Information Technology (CS1)
Q.14 Consider a demand paging memory management system with 32-bit logical
address, 20-bit physical address, and page size of 2048 bytes. Assuming that the
memory is byte addressable, what is the maximum number of entries in the page
table?
(A) 221
(B) 220
(C) 222
(D) 224
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Computer Science and Information Technology (CS1)
Q.15 A schedule of three database transactions T1 , T2 , and T3 is shown. Ri (A) and
Wi (A) denote read and write of data item A by transaction Ti , i = 1,2,3. The
transaction T1 aborts at the end. Which other transaction(s) will be required to be
rolled back?
R1 (X) W1 (Y) R2 (X) R2 (Y) R3 (Y) ABORT(T1 )
(A) Only T2
(B) Only T3
(C) Both T2 and T3
(D) Neither T2 nor T3
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Computer Science and Information Technology (CS1)
Q.16 Identify the ONE CORRECT matching between the OSI layers and their
corresponding functionalities as shown.
OSI Layers Functionalities
(a) Network layer (I) Packet routing
(b) Transport layer (II) Framing and error handling
(c) Datalink layer (III) Host to host communication
(A) (a)-(I), (b)-(II), (c)-(III)
(B) (a)-(I), (b)-(III), (c)-(II)
(C) (a)-(II), (b)-(I), (c)-(III)
(D) (a)-(III), (b)-(II), (c)-(I)
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Computer Science and Information Technology (CS1)
Q.17 g(. ) is a function from A to B, f(. ) is a function from B to C, and their
composition defined as f(g(. )) is a mapping from A to C.
If f(. ) and f(g(. )) are onto (surjective) functions, which ONE of the following
is TRUE about the function g(. )?
(A) g(. ) must be an onto (surjective) function.
(B) g(. ) must be a one-to-one (injective) function.
(C) g(. ) must be a bijective function, that is, both one-to-one and onto.
(D) g(. ) is not required to be a one-to-one or onto function.
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Computer Science and Information Technology (CS1)
Q.18 Let G be any undirected graph with positive edge weights, and T be a minimum
spanning tree of G. For any two vertices, u and v, let d1 (u, v) and d2 (u, v) be the
shortest distances between u and v in G and T, respectively. Which ONE of the
options is CORRECT for all possible G, T, u and v?
(A) d1 (u, v) = d2 (u, v)
(B) d1 (u, v) ≤ d2 (u, v)
(C) d1 (u, v) ≥ d2 (u, v)
(D) d1 (u, v) ≠ d2 (u, v)
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Computer Science and Information Technology (CS1)
Q.19 Consider the following context-free grammar G, where S, A, and B are the variables
(non-terminals), a and b are the terminal symbols, S is the start variable, and the
rules of G are described as:
S → aaB | Abb
A → a | aA
B → b | bB
Which ONE of the languages L(G) is accepted by G?
(A) L(G) = {a2 b n | n ≥ 1} ∪ {an b 2 | n ≥ 1}
(B) L(G) = {an b 2n | n ≥ 1} ∪ {a2n b n | n ≥ 1}
(C) L(G) = {an b n | n ≥ 1}
(D) L(G) = {a2n b 2n | n ≥ 1}
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Computer Science and Information Technology (CS1)
Consider the following recurrence relation:
Q.20
T(n) = 2T(n − 1) + n2n for n > 0, T(0) = 1.
Which ONE of the following options is CORRECT?
(A) T(n) = Θ(n2 2n )
(B) T(n) = Θ(n2n )
(C) T(n) = Θ((log n)2 2n )
(D) T(n) = Θ(4n )
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Computer Science and Information Technology (CS1)
Q.21 Consider the following B + tree with 5 nodes, in which a node can store at most 3 key values.
The value 23 is now inserted in the B + tree. Which of the following options(s) is/are
CORRECT?
(A) None of the nodes will split.
(B) At least one node will split and redistribute.
(C) The total number of nodes will remain same.
(D) The height of the tree will increase.
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Computer Science and Information Technology (CS1)
Q.22 Consider the 3-way handshaking protocol for TCP connection establishment. Let
the three packets exchanged during the connection establishment be denoted as P1,
P2, and P3, in order. Which of the following option(s) is/are TRUE with respect to
TCP header flags that are set in the packets?
(A) P3: SYN = 1, ACK = 1
(B) P2: SYN = 1, ACK = 1
(C) P2: SYN = 0, ACK = 1
(D) P1: SYN = 1
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Computer Science and Information Technology (CS1)
Consider the given system of linear equations for variables x and y, where k is a
Q.23 real-valued constant. Which of the following option(s) is/are CORRECT?
x + ky = 1
kx + y = −1
(A) There is exactly one value of k for which the above system of equations has no
solution.
(B) There exist an infinite number of values of k for which the system of equations has
no solution.
(C) There exists exactly one value of k for which the system of equations has exactly
one solution.
(D) There exists exactly one value of k for which the system of equations has an infinite
number of solutions.
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Computer Science and Information Technology (CS1)
Q.24 Let X be a 3-variable Boolean function that produces output as ‘1’ when at least
two of the input variables are ‘1’. Which of the following statement(s) is/are
CORRECT, where a, b, c, d, e are Boolean variables?
(A) X(a, b, X(c, d, e)) = X(X(a, b, c), d, e)
(B) X(a, b, X(a, b, c)) = X(a, b, c)
(C) X(a, b, X(a, c, d)) = (X(a, b, a) AND X(c, d, c))
(D) X(a, b, c) = X(a, X(a, b, c), X(a, c, c))
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Computer Science and Information Technology (CS1)
Q.25 The number −6 can be represented as 1010 in 4-bit 2’s complement representation.
Which of the following is/are CORRECT 2’s complement representation(s) of −6?
(A) 1000 1010 in 8-bits
(B) 1111 1010 in 8-bits
(C) 1000 0000 0000 1010 in 16-bits
(D) 1111 1111 1111 1010 in 16-bits
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Computer Science and Information Technology (CS1)
Q.26 Which of the following statement(s) is/are TRUE for any binary search tree (BST)
having n distinct integers?
(A) The maximum length of a path from the root node to any other node is (n − 1).
(B) An inorder traversal will always produce a sorted sequence of elements.
(C) Finding an element takes O(log 2 n) time in the worst case.
(D) Every BST is also a Min-Heap.
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Computer Science and Information Technology (CS1)
Q.27 A partial data path of a processor is given in the figure, where RA, RB, and RZ are
32-bit registers. Which option(s) is/are CORRECT related to arithmetic operations
using the data path as shown?
(A) The data path can implement arithmetic operations involving two registers.
(B) The data path can implement arithmetic operations involving one register and one
immediate value.
(C) The data path can implement arithmetic operations involving two immediate values.
(D) The data path can only implement arithmetic operations involving one register and
one immediate value.
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Computer Science and Information Technology (CS1)
Q.28 A regular language L is accepted by a non-deterministic finite automaton (NFA)
with n states. Which of the following statement(s) is/are FALSE?
(A) L may have an accepting NFA with < n states.
(B) L may have an accepting DFA with < n states.
(C) There exists a DFA with ≤ 2n states that accepts L.
(D) Every DFA that accepts L has > 2n states.
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Computer Science and Information Technology (CS1)
Q.29 Suppose in a multiprogramming environment, the following C program segment is
executed. A process goes into I/O queue whenever an I/O related operation is
performed. Assume that there will always be a context switch whenever a process
requests for an I/O, and also whenever the process returns from an I/O. The number
of times the process will enter the ready queue during its lifetime (not counting the
time the process enters the ready queue when it is run initially) is _______. (Answer
in integer)
int main()
{
int x=0,i=0;
scanf("%d",&x);
for(i=0; i<20; i++)
{
x = x+20;
printf("%d\n",x);
}
return 0;
}
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Computer Science and Information Technology (CS1)
Q.30 Let S be the set of all ternary strings defined over the alphabet {a, b, c}. Consider
all strings in S that contain at least one occurrence of two consecutive symbols, that
is, “aa”, “bb” or “cc”. The number of such strings of length 5 that are possible is
_______. (Answer in integer)
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Computer Science and Information Technology (CS1)
Q.31 Consider the given function f(x).
ax + b for x < 1
f(x) = { 3 2
x + x + 1 for x ≥ 1
If the function is differentiable everywhere, the value of b must be ________.
(rounded off to one decimal place)
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Computer Science and Information Technology (CS1)
Q.32 A box contains 5 coins: 4 regular coins and 1 fake coin. When a regular coin is
tossed, the probability P(ℎead) = 0.5 and for a fake coin, P(ℎead) = 1. You pick
a coin at random and toss it twice, and get two heads. The probability that the coin
you have chosen is the fake coin is _______. (rounded off to two decimal places)
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Computer Science and Information Technology (CS1)
Q.33 The pseudocode of a function fun() is given below:
fun(int A[0,…,n-1]){
for i=0 to n-2
for j=0 to n-i-2
if (A[j]>A[j+1])
then swap A[j] and A[j+1]
}
Let A[0, … ,29] be an array storing 30 distinct integers in descending order. The
number of swap operations that will be performed, if the function fun() is called
with A[0, … ,29] as argument, is __________. (Answer in integer)
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Computer Science and Information Technology (CS1)
Q.34 #include <stdio.h>
void foo(int *p, int x){
*p=x;
}
int main(){
int *z;
int a = 20, b = 25;
z = &a;
foo(z,b);
printf("%d",a);
return 0;
}
The output of the given C program is __________. (Answer in integer)
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Computer Science and Information Technology (CS1)
Q.35 The height of any rooted tree is defined as the maximum number of edges in the
path from the root node to any leaf node.
Suppose a Min-Heap T stores 32 keys. The height of T is _____________.
(Answer in integer)
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Computer Science and Information Technology (CS1)
Q.36 – Q.65 Carry TWO marks Each
Q.36 Consider a memory system with 1M bytes of main memory and 16K bytes of cache
memory. Assume that the processor generates 20-bit memory address, and the cache
block size is 16 bytes. If the cache uses direct mapping, how many bits will be
required to store all the tag values? [Assume memory is byte addressable, 1K=210,
1M=220 .]
(A) 6 × 210
(B) 8 × 210
(C) 212
(D) 214
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Computer Science and Information Technology (CS1)
Q.37 A processor has 64 general-purpose registers and 50 distinct instruction types. An
instruction is encoded in 32-bits. What is the maximum number of bits that can be
used to store the immediate operand for the given instruction?
ADD R1, #25 // R1 = R1 + 25
(A) 16
(B) 20
(C) 22
(D) 24
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Computer Science and Information Technology (CS1)
Q.38 A computer has two processors, M1 and M2 . Four processes P1 , P2 , P3 , P4 with CPU
bursts of 20, 16, 25, and 10 milliseconds, respectively, arrive at the same time and
these are the only processes in the system. The scheduler uses non-preemptive
priority scheduling, with priorities decided as follows:
• M1 uses priority of execution for the processes as, P1 > P3 > P2 > P4 , i.e.,
P1 and P4 have highest and lowest priorities, respectively.
• M2 uses priority of execution for the processes as, P2 > P3 > P4 > P1 , i.e.,
P2 and P1 have highest and lowest priorities, respectively.
A process Pi is scheduled to a processor Mk , if the processor is free and no other
process Pj is waiting with higher priority. At any given point of time, a process can
be allocated to any one of the free processors without violating the execution
priority rules. Ignore the context switch time. What will be the average waiting time
of the processes in milliseconds?
(A) 9.00
(B) 8.75
(C) 6.50
(D) 7.50
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Computer Science and Information Technology (CS1)
Q.39 Consider two relations describing teams and players in a sports league:
• teams(tid, tname): tid, tname are team-id and team-name, respectively
• players(pid, pname, tid): pid, pname, and tid denote player-id, player-
name and the team-id of the player, respectively
Which ONE of the following tuple relational calculus queries returns the name of the
players who play for the team having tname as ′MI′?
(A) { p. pname | p ∈ players ∧ ∃t (t ∈ teams ∧ p. tid = t. tid ∧ t. tname = ′MI′)}
(B) { p. pname | p ∈ teams ∧ ∃t (t ∈ players ∧ p. tid = t. tid ∧ t. tname = ′MI′)}
(C) { p. pname | p ∈ players ∧ ∃t (t ∈ teams ∧ t. tname = ′MI′)}
(D) { p. pname | p ∈ teams ∧ ∃t (t ∈ players ∧ t. tname = ′MI′)}
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Q.40 A packet with the destination IP address 145.36.109.70 arrives at a router whose
routing table is shown. Which interface will the packet be forwarded to?
(A) E3
(B) E1
(C) E2
(D) E5
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Computer Science and Information Technology (CS1)
Let A be a 2 × 2 matrix as given.
Q.41 1 1
A=[ ]
1 −1
What are the eigenvalues of the matrix A13 ?
(A) 1, −1
(B) 2√2, −2√2
(C) 4√2, −4√2
(D) 64√2, −64√2
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Computer Science and Information Technology (CS1)
Q.42 Consider the following four variable Boolean function in sum-of-product form
F(b3 , b2 , b1 , b0 ) = ∑(0, 2, 4, 8, 10, 11, 12).
where the value of the function is computed by considering b3 b2 b1 b0 as a 4-bit
binary number, where b3 denotes the most significant bit and b0 denotes the least
significant bit. Note that there are no don’t care terms. Which ONE of the following
options is the CORRECT minimized Boolean expression for F?
(A) b̅1 b̅0 + b̅2 b̅0 + b1 b̅2 b3
(B) b̅1 b̅0 + b̅2 b̅0
(C) b̅2 b̅0 + b1 b2 b3
(D) b̅0 b̅2 + b̅3
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Computer Science and Information Technology (CS1)
Q.43 Let G(V, E) be an undirected and unweighted graph with 100 vertices. Let d(u, v)
denote the number of edges in a shortest path between vertices u and v in V. Let the
maximum value of d(u, v), u, v ∈ V such that u ≠ v, be 30. Let T be any breadth-
first-search tree of G. Which ONE of the given options is CORRECT for every such
graph G?
(A) The height of T is exactly 15.
(B) The height of T is exactly 30.
(C) The height of T is at least 15.
(D) The height of T is at least 30.
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Computer Science and Information Technology (CS1)
Q.44 Consider the following two languages over the alphabet {a, b}:
L1 = { αβα | α ∈ {a, b}+ AND β ∈ {a, b}+ }
L2 = { αβα | α ∈ {a}+ AND β ∈ {a, b}+ }
Which ONE of the following statements is CORRECT?
(A) Both L1 and L2 are regular languages.
(B) L1 is a regular language but L2 is not a regular language.
(C) L1 is not a regular language but L2 is a regular language.
(D) Neither L1 nor L2 is a regular language.
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Computer Science and Information Technology (CS1)
Q.45 Consider the following two languages over the alphabet {a, b, c}, where m and n
are natural numbers.
L1 = {am b m c m+n | m, n ≥ 1}
L2 = {am b n c m+n | m, n ≥ 1}
Which ONE of the following statements is CORRECT?
(A) Both L1 and L2 are context-free languages.
(B) L1 is a context-free language but L2 is not a context-free language.
(C) L1 is not a context-free language but L2 is a context-free language.
(D) Neither L1 nor L2 are context-free languages.
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Computer Science and Information Technology (CS1)
Q.46 Which of the following statement(s) is/are TRUE while computing First and Follow
during top down parsing by a compiler?
(A) For a production A → ε, ε will be added to First(A).
(B) If there is any input right end marker, it will be added to First(S), where S is the
start symbol.
(C) For a production A → ε, ε will be added to Follow(A).
(D) If there is any input right end marker, it will be added to Follow(S), where S is
the start symbol.
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Computer Science and Information Technology (CS1)
Q.47 Consider a relational schema team(name, city, owner), with functional
dependencies {name → city, name → owner}.
The relation team is decomposed into two relations, t1(name, city) and
t2(name, owner). Which of the following statement(s) is/are TRUE?
(A) The relation team is NOT in BCNF.
(B) The relations t1 and t2 are in BCNF.
(C) The decomposition constitutes a lossless join.
(D) The relation team is NOT in 3NF.
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Computer Science and Information Technology (CS1)
Q.48 Which of the following predicate logic formulae/formula is/are CORRECT
representation(s) of the statement: “Everyone has exactly one mother”?
The meanings of the predicates used are:
• motℎer(y, x): y is the mother of x
• noteq(x, y): x and y are not equal
(A) ∀x∃y∃z(motℎer(y, x) ∧ ¬motℎer(z, x))
(B) ∀x∃y[motℎer(y, x) ∧ ∀z(noteq(z, y) → ¬motℎer(z, x))]
(C) ∀x∀y[motℎer(y, x) → ∃z(motℎer(z, x) ∧ ¬noteq(z, y))]
(D) ∀x∃y[motℎer(y, x) ∧ ¬∃z(noteq(z, y) ∧ motℎer(z, x))]
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Computer Science and Information Technology (CS1)
Q.49 A = {0, 1, 2, 3, … } is the set of non-negative integers. Let Ϝ be the set of functions
from A to itself. For any two functions, f1 , f2 ∈ Ϝ, we define
(f1 ⨀f2 )(n) = f1 (n) + f2 (n)
for every number n in A. Which of the following is/are CORRECT about the
mathematical structure (Ϝ, ⨀)?
(A) (Ϝ, ⨀) is an Abelian group.
(B) (Ϝ, ⨀) is an Abelian monoid.
(C) (Ϝ, ⨀) is a non-Abelian group.
(D) (Ϝ, ⨀) is a non-Abelian monoid.
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Computer Science and Information Technology (CS1)
Q.50 Consider the following deterministic finite automaton (DFA) defined over the
alphabet, Σ = {a, b}. Identify which of the following language(s) is/are accepted by
the given DFA.
(A) The set of all strings containing an even number of b’s.
(B) The set of all strings containing the pattern bab.
(C) The set of all strings ending with the pattern bab.
(D) The set of all strings not containing the pattern aba.
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Computer Science and Information Technology (CS1)
Q.51 A disk of size 512M bytes is divided into blocks of 64K bytes. A file is stored in
the disk using linked allocation. In linked allocation, each data block reserves 4
bytes to store the pointer to the next data block. The link part of the last data block
contains a NULL pointer (also of 4 bytes). Suppose a file of 1M bytes needs to be
stored in the disk. Assume, 1K = 210 and 1M = 220 . The amount of space in bytes
that will be wasted due to internal fragmentation is ______. (Answer in integer)
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Computer Science and Information Technology (CS1)
Q.52 Refer to the given 3-address code sequence. This code sequence is split into basic
blocks. The number of basic blocks is ________. (Answer in integer)
1001: i = 1
1002: j = 1
1003: t1 = 10*i
1004: t2 = t1+j
1005: t3 = 8*t2
1006: t4 = t3-88
1007: a[t4] = 0.0
1008: j = j+1
1009: if j <= 10 goto 1003
1010: i = i+1
1011: if i <= 10 goto 1002
1012: i = 1
1013: t5 = i-1
1014: t6 = 88*t5
1015: a[t6] = 1.0
1016: i = i+1
1017: if i <= 10 goto 1013
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Computer Science and Information Technology (CS1)
Q.53 A computer has a memory hierarchy consisting of two-level cache (L1 and L2) and
a main memory. If the processor needs to access data from memory, it first looks
into L1 cache. If the data is not found in L1 cache, it goes to L2 cache. If it fails to
get the data from L2 cache, it goes to main memory, where the data is definitely
available. Hit rates and access times of various memory units are shown in the
figure. The average memory access time in nanoseconds (ns) is ________. (rounded
off to two decimal places)
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Computer Science and Information Technology (CS1)
Q.54 In optimal page replacement algorithm, information about all future page references
is available to the operating system (OS). A modification of the optimal page
replacement algorithm is as follows:
The OS correctly predicts only up to next 4 page references (including the current
page) at the time of allocating a frame to a page.
A process accesses the pages in the following order of page numbers:
1, 3, 2, 4, 2, 3, 1, 2, 4, 3, 1, 4.
If the system has three memory frames that are initially empty, the number of page
faults that will occur during execution of the process is ________ . (Answer in
integer)
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Computer Science and Information Technology (CS1)
Q.55 Consider the following database tables of a sports league.
player(pid,pname,age) team(tid,tname,city,cid)
coach(cid,cname) members(pid,tid)
An instance of the table and an SQL query are given.
player coach team members
SELECT MIN(P.age)
FROM player P
WHERE P.pid IN (
SELECT M.pid
FROM team T, coach C, members M
WHERE C.cname = 'Mark'
AND T.cid = C.cid
AND M.tid = T.tid
)
The value returned by the given SQL query is ______ . (Answer in integer)
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Computer Science and Information Technology (CS1)
Q.56 Suppose a 5-bit message is transmitted from a source to a destination through a
noisy channel. The probability that a bit of the message gets flipped during
transmission is 0.01. Flipping of each bit is independent of one another. The
probability that the message is delivered error-free to the destination is ______ .
(rounded off to three decimal places)
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Computer Science and Information Technology (CS1)
Q.57 Suppose a message of size 15000 bytes is transmitted from a source to a destination
using IPv4 protocol via two routers as shown in the figure. Each router has a defined
maximum transmission unit (MTU) as shown in the figure, including IP header.
The number of fragments that will be delivered to the destination is ________ .
(Answer in integer)
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Computer Science and Information Technology (CS1)
Q.58 Consider a probability distribution given by the density function P(x).
Cx 2 , for 1 ≤ x ≤ 4
P(x) = {
0, for x < 1 or x > 4
The probability that x lies between 2 and 3, i.e., P(2 ≤ x ≤ 3) is __________.
(rounded off to three decimal places)
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Computer Science and Information Technology (CS1)
Q.59 Consider a finite state machine (FSM) with one input X and one output f,
represented by the given state transition table. The minimum number of states
required to realize this FSM is ________. (Answer in integer)
Present state Next state Output f
X=0 X=1 X=0 X=1
A F B 0 0
B D C 0 0
C F E 0 0
D G A 1 0
E D C 0 0
F F B 1 1
G G H 0 1
H G A 1 0
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Computer Science and Information Technology (CS1)
Q.60 Consider the given sequential circuit designed using D-Flip-flops. The circuit is
initialized with some value (initial state). The number of distinct states the circuit
will go through before returning back to the initial state is _________ . (Answer
in integer)
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Computer Science and Information Technology (CS1)
Q.61 #include <stdio.h>
int foo(int S[],int size){
if(size == 0) return 0;
if(size == 1) return 1;
if(S[0] != S[1]) return 1+foo(S+1,size-1);
return foo(S+1,size-1);
}
int main(){
int A[]={0,1,2,2,2,0,0,1,1};
printf("%d",foo(A,9));
return 0;
}
The value printed by the given C program is _______ . (Answer in integer)
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Computer Science and Information Technology (CS1)
Q.62 Let LIST be a datatype for an implementation of linked list defined as follows:
typedef struct list {
int data;
struct list *next;
} LIST;
Suppose a program has created two linked lists, L1 and L2, whose contents are given
in the figure below (code for creating L1 and L2 is not provided here). L1 contains 9
nodes, and L2 contains 7 nodes.
Consider the following C program segment that modifies the list L1. The number of
nodes that will be there in L1 after the execution of the code segment is ________ .
(Answer in integer)
int find (int query, LIST *list) {
while (list != NULL){
if(list->data == query) return 1;
list = list->next;
}
return 0;
}
int main () {
… … …
ptr1=L1; ptr2=L2;
while (ptr1->next != NULL){
query = ptr1->next->data;
if (find (query, L2))
ptr1->next = ptr1->next->next;
else ptr1 = ptr1->next;
}
… … …
return 0;
}
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Computer Science and Information Technology (CS1)
Q.63 Consider the following C program:
#include <stdio.h>
int gate (int n) {
int d, t, newnum, turn;
newnum = turn = 0; t=1;
while (n>=t) t *= 10;
t /=10;
while (t>0) {
d = n/t;
n = n%t;
t /= 10;
if (turn) newnum = 10*newnum + d;
turn = (turn + 1) % 2;
}
return newnum;
}
int main () {
printf ("%d", gate(14362));
return 0;
}
The value printed by the given C program is _______ . (Answer in integer)
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Computer Science and Information Technology (CS1)
Q.64 The maximum value of x such that the edge between the nodes B and C is included
in every minimum spanning tree of the given graph is _________ . (answer in
integer)
Q.65 In a double hashing scheme, ℎ1 (k) = k mod 11 and ℎ2 (k) = 1 + (k mod 7) are
the auxiliary hash functions. The size m of the hash table is 11. The hash function
for the i-th probe in the open address table is [ℎ1 (k) + i ℎ2 (k)] mod m. The
following keys are inserted in the given order: 63, 50, 25, 79, 67, 24.
The slot at which key 24 gets stored is ___________. (Answer in integer)
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Answer Key for Computer Science and Information Technology 1 (CS1)
Q. No. Session Q. Type Section Key/Range Marks
1 1 MCQ GA A 1
2 1 MCQ GA B 1
3 1 MCQ GA C 1
4 1 MCQ GA A 1
5 1 MCQ GA C 1
6 1 MCQ GA C 2
7 1 MCQ GA A 2
8 1 MCQ GA A 2
9 1 MCQ GA A 2
10 1 MCQ GA B 2
11 1 MCQ CS-1 A 1
12 1 MCQ CS-1 C 1
13 1 MCQ CS-1 B 1
14 1 MCQ CS-1 A 1
15 1 MCQ CS-1 C 1
16 1 MCQ CS-1 B 1
17 1 MCQ CS-1 D 1
18 1 MCQ CS-1 B 1
19 1 MCQ CS-1 A 1
20 1 MCQ CS-1 A 1
21 1 MSQ CS-1 B;D 1
22 1 MSQ CS-1 B;D 1
23 1 MSQ CS-1 A;D 1
24 1 MSQ CS-1 B;D 1
25 1 MSQ CS-1 B;D 1
26 1 MSQ CS-1 A;B 1
27 1 MSQ CS-1 A;B;C 1
28 1 MSQ CS-1 D 1
29 1 NAT CS-1 21 to 21 1
30 1 NAT CS-1 195 to 195 1
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31 1 NAT CS-1 -2.1 to -1.9 1
32 1 NAT CS-1 0.49 to 0.51 1
33 1 NAT CS-1 435 to 435 1
34 1 NAT CS-1 25 to 25 1
35 1 NAT CS-1 5 to 5 1
36 1 MCQ CS-1 A 2
37 1 MCQ CS-1 B 2
38 1 MCQ CS-1 A 2
39 1 MCQ CS-1 A 2
40 1 MCQ CS-1 A 2
41 1 MCQ CS-1 D 2
42 1 MCQ CS-1 A 2
43 1 MCQ CS-1 C 2
44 1 MCQ CS-1 C 2
45 1 MCQ CS-1 C 2
46 1 MSQ CS-1 A;D 2
47 1 MSQ CS-1 B;C 2
48 1 MSQ CS-1 B;D 2
49 1 MSQ CS-1 B 2
50 1 MSQ CS-1 C 2
51 1 NAT CS-1 65468 to 65468 2
52 1 NAT CS-1 6 to 6 2
53 1 NAT CS-1 11.83 to 11.87 2
54 1 NAT CS-1 6 to 6 2
55 1 NAT CS-1 26 to 26 2
56 1 NAT CS-1 0.949 to 0.952 2
57 1 NAT CS-1 7 to 7 2
58 1 NAT CS-1 0.300 to 0.302 2
59 1 NAT CS-1 5 to 5 2
60 1 NAT CS-1 7 to 8 2
61 1 NAT CS-1 5 to 5 2
62 1 NAT CS-1 5 to 5 2
63 1 NAT CS-1 46 to 46 2
64 1 NAT CS-1 5 to 5 2
65 1 NAT CS-1 10 to 11 2
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Source: GATE. Question paper published by GATE.