GATE question papers: Computer Science and Engineering 2005 (CS)
Q.1 - Q.30 carry one mark each.
1. What does the following C-statement declare?
int ( * f) (int * ) ;
(a) A function that takes an integer
pointer as argument and returns an integer
(b) A function that takes an integer
as argument and returns an integer pointer
(c) A pointer to a function that
takes an integer pointer as argument and returns an integer.
(d) A function that takes an integer
pointer as argument and returns a function pointer
2. An Abstract Data Type (ADT) is:
(a) same as an abstract class
(b) a data type that cannot be
instantiated
(c) a data type for which only the
operations defined on it can be used, but none else
(d) all of the above
3. A common property of logic programming
languages and functional languages is:
(a) both are procedural languages
(b) both are based on l-calculus
(c) both are declarative
(d) both use Horn-clauses
4. Which one of the following are essential
features of an object-oriented programming language?
(i) Abstraction and encapsulation
(ii) Strictly-typedness
(iii) Type-safe property coupled with
sub-type rule
(iv) Polymorphism in the presence of
inheritance
(a) (i) and (ii) only (b) (i)
and (iv) only
(c) (i), (ii) and (iv) only (d)
(i), (iii) and (iv) only
5. A program P reads in 500 integers in the
range [0,100] representing the scores of 500 students. It then prints the
frequency of each score above 50. What would be the best way for P to store the
frequencies?
(a) An array of 50 numbers
(b) An array of 100 numbers
(c) An array of 500 numbers
(d) A dynamically allocated array of
550 numbers
6. An undirected graph G has n nodes. Its
adjacency matrix is given by an n ´ n
square matrix whose (i) diagonal elements are 0's and (ii) non-diagonal elements
are 1's. which one of the following is TRUE?
(a) Graph G has no minimum spanning
tree (MST)
(b) Graph G has a unique MST of cost
n-1
(c) Graph G has multiple distinct
MSTs, each of cost n-1
(d) Graph G has multiple spanning
trees of different costs
7. The time complexity of computing the
transitive closure of a binary relation on a set of n elements is known to be:
(a) O(n) (b) O(n
log n) (c) (d) O(n3)
8. Let A, B and C be non-empty sets and let
X = (A -
B) - C and Y = (A - C) -
(B - C)
Which one of the
following is TRUE?
(a) X = Y (b) X
Ì Y (c) Y Ì X (d) None of these
9. The following is the Hasse diagram of the
poset [{a,b,c,d,e},]
The poset is:
(a) not a lattice
(b) a lattice but not a distributive
lattice
(c) a distributive lattice but not a
Boolean algebra
(d) a Boolean algebra
10. Let G be a simple
connected planar graph with 13 vertices and 19 edges. Then, the number of faces
in the planar embedding of the graph is:
(a) 6 (b) 8
(c) 9 (d) 13
11. 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:
(a) 12 (b) 8
(c) Less than 8 (d) More than 12
12. Let f(x) be the continuous probability
density function of a random variable X.
The probability that a < X b, is:
(a) f (b - a) (b) f (b) -
f(a) (c) (d)
13. The set {1, 2, 4, 7, 8, 11, 13, 14} is a
group under multiplication modulo 15. The inverses of 4 and 7 are respectively:
(a) and 13 (b) 2
and 11 (c) 4 and 13 (d) 8 and 14
14. The grammar A ®
AA | (A) | e is not suitable for
predictive-parsing because the grammar is:
(a) ambiguous (b) left-recursive
(c) right-recursive (d)
an operator-grammar
15. Consider the following circuit.
Which one of the
following is TRUE?
(a) f is
independent of X (b) f is independent of Y
(c) f is
independent of Z (d) None of X, Y, Z is
redundant
16. The range of
integers that can be represented by an n bit 2's complement number system is:
(a) -2n-1
to (2n-1
- 1) (b) -2(2n-1
- 1) to (2n-1 -
1)
(c) -2n-1
to 2n-1 (d) -2(2n-1
+ 1) to (2n-1
- 1)
17. The hexadecimal
representation of 6578 is:
(a) 1AF (b)
D78 (c) D71 (d) 32F
18. The switching
expression corresponding to f(A,B,C,D)= is:
(a) BC¢D¢ +
A¢C¢D
+ AB¢D (b) ABC¢ + ACD + B¢C¢D
(C) ACD¢ + A¢BC¢ + AC¢D¢ (c) A¢BD + ACD¢
+ BCD¢
19. Which one of the
following is true for a CPU having a single interrupt request line and a single
interrupt grant line?
(a) Neither
vectored interrupt nor multiple interrupting devices are possible
(b) Vectored
interrupts are not possible but multiple interrupting devices are possible.
(c) Vectored
interrupts and multiple interrupting devices are both possible
(d) Vectored
interrupt is possible but multiple interrupting devices are not possible
20. Normally user
programs are prevented from handling I/O directly by I/O instructions in them.
For CPUs having explicit I/O instructions, such I/O protection is ensured by
having the I/O instructions privileged. In a CPU with memory mapped I/O, there
is no explicit I/O instruction. Which one of the following is true for a CPU
with memory mapped I/O?
(a) I/O
protection is ensured by operating system routine(s)
(b) I/O
protection is ensured by a hardware trap
(c) I/O
protection is ensured during system configuration
(d) I/O
protection is not possible
21. What is the swap
space in the disk used for?
(a) Saving temporary html pages (b) Saving
process data
(c) Storing the super-block (d) Storing
device drivers
22. Increasing the
RAM of a computer typically improves performance because:
(a) Virtual memory increases (b) Larger
RAMs are faster
(c) Fewer page faults occur (d) Fewer
segmentation faults occur
23. Packets of the
same session may be routed through different paths in:
(a) TCP, but not UDP (b) TCP
and UDP
(c) UDP, but not TCP (d) Neither
TCP nor UDP
24. The address
resolution protocol (ARP) is used for:
(a) Finding the IP address from the
DNS
(b) Finding the IP address of the
default gateway
(c) Finding the IP address that
corresponds to a MAC address
(d) Finding the MAC address that
corresponds to an IP address
25. The maximum window size for data transmission
using the selective reject protocol with n-bit frame sequence numbers is:
(a) 2n (b) 2n-1 (c) 2n -
1 (d) 2n-2
26. 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?
(a) For
shortest path routing between LANs
(b) For
avoiding loops in the routing paths
(c) For
fault tolerance
(d) For minimizing collisions
27. An organization
has a class B network and wishes to form subnets for 64 departments. The subnet
mask would be:
(a) 255.255.0.0 (b) 255.255.64.0
(c) 255.255.128.0 (d) 255.255.252.0
28. Which one of the following is a key factor
for preferring B+-trees to
binary search trees for indexing database relations?
(a) Database relations have a large
number of records
(b) Database relations are sorted on
the primary key
(c) B+-trees require less memory than binary search trees
(d) Data transfer form disks is in
blocks
29. Which one of the following statements about
normal forms is FALSE?
(a) BCNF is stricter than 3NF
(b) Lossless, dependency-preserving
decomposition into 3NF is always possible
(c) Lossless, dependency-preserving
decomposition into BCNF is always possible
(d) Any relation with two attributes
is in BCNF
30. Let r be a
relation instance with schema R = (A, B, C, D). We define r1 = PA,B,C (R) and r2 = PA,D (r). Let s = r1 *
r2 where * denotes natural join. Given that the decomposition of r
into r1 and r2 is lossy, which one of the following is
TRUE?
(a) s Ì
r (b) r È s = r (c) r
Ì s (d) r * s =
s
Q.31 to Q.80
carry two m arks each.
31. Consider the
following C-program:
void foo (int n,
int sum 0) {
int k = 0, j =
0;
if (n==0)
return;
k = n % 10; j =
n / 10;
sum = sum + k;
foo (j, sum);
printf
("%d,", k);
}
int main () {
int a = 2048,
sum = 0;
foo (a, sum);
printf("%d\n",
sum);
}
What does the above program print?
(a) 8, 4, 0, 2, 14 (b) 8,
4, 0, 2, 0 (c) 2, 0, 4, 8, 14 (d) 2, 0, 4, 8, 0
32. Consider the following C-program:
double foo (double); /* Line 1 */
int main () {
double da, db;
// input da
db = foo (da);
}
double foo (double a) {
return a;
}
The above code compiled without any error or
warning. If Line 1 is deleted, the above code will show:
(a) no compile warning or error
(b) some compiler-warnings not
leading to unintended results
(c) some compiler-warnings due to
type-mismatch eventually leading to unintended results
(d) compiler errors
33. Postorder traversal of a given binary search
tree, T produces the following sequence of keys
10,
9, 23, 22, 27, 25, 15, 50, 95, 60, 40, 29
Which one of the following sequences of keys
can be the result of an in-order traversal of the tree T?
(a) 9, 10, 15, 22, 23, 25, 27, 29,
40, 50, 60, 95
(b) 9, 10, 15, 22, 40, 50, 60, 95,
23, 25, 27, 29
(c) 29, 15, 9, 10, 25, 22, 23, 27,
40, 60, 50, 95
(d) 95, 50, 60, 40, 27, 23, 22, 25,
10, 9, 15, 29
34. 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:
(a) 10, 8, 7, 5, 3, 2, 1 (b) 10,
8, 7, 2, 3, 1, 5
(c) 10, 8, 7, 1, 2, 3, 5 (d) 10,
8, 7, 3, 2, 1, 5
35. How many distinct
binary search trees can be created out of 4 distinct keys?
(a) 5 (b) 14
(c) 24 (d) 42
36. In a complete k-ary tree, every internal node
has exactly k children. The number of leaves in such a tree with n internal
nodes is:
(a) nk (b) (n
- 1) k + 1 (c) n(k - 1) + 1 (d) n(k - 1)
37. Suppose T (n) = 2T + n, T (0) = T(1) = 1
Which one of the
following is FALSE?
(a) T(n) = O(n2) (b) T(n)
= q (n log n)
(c) T(n) = W (n2) (d) T(n)
= O (n log n)
38. Let G(V,E) be an undirected graph with
positive edge weights. Dijkstra's single source shortest path algorithm can be
implemented using the binary heap data structure with time complexity:
(a) O (|V|2) (b) O(|E|
+ |V|log|V|)
(c) O(|V|log|V|) (d) O((|E|
+ |V|) log |V|)
39. Suppose there are [log n] sorted lists of
[n/log n] elements each. The time complexity of producing a sorted list of all
these elements is: (Hint: Use a heap data structure)
(a) O (n log log n) (b) q (n log n) (c) W (n log n) (d) W
40. Let P, Q and R be
tree atomic prepositional assertions. Let X denote (P Ú Q) ® R and Y denote
(P ® R) Ú
(Q ® R). Which one of the following is
a tautology?
(a) X º
Y (b) X ® Y (c)
Y ® X (d) ¬Y
® X
41. What is the first
order predicate calculus statement equivalent to the following?
Every teacher is
liked by some student
(a) "(x)[teacher(x) ® $(y) [student(y) ® likes (y,x)]]
(b) "(x)[teacher(x) ® $(y) [student(y) Ù likes (y,x)]]
(c) $(y) "(x)[teacher(x)
® [student(y) Ù likes (y,x)]]
(d) "(x)[teacher(x) Ù $(y) [student(y) ® likes (y,x)]]
42. Let R and S be any two equivalence relations
on a non-empty set A. Which one of the following statements is TRUE?
(a) R È
S, R Ç S are both equivalence
relations.
(b) R È
S is an equivalence relation.
(c) R Ç
S is an equivalence relation.
(d) Neither R È S nor R Ç S is an
equivalence relation
43. Let f: B ®
C and g: A ® B be two functions let h
= f ° g. Given that h is an onto
function which one of the following is TRUE?
(a) f and g should both be onto
functions
(b) f should be onto but g need to be
onto
(c) g should be onto but f need not
be onto
(d) both f and g need to be onto
44. What is the minimum number of ordered pairs
of non-negative numbers that should be chosen to ensure that there are two
pairs (a,b) and (c,d) in the chosen set such that
a º
c mod 3 and b º d mod 5
(a) 4 (b) 6
(c) 16 (d) 24
45. Consider three decision problems P1,
P2 and P3. It is known that P1 is decidable
and P2 is undecidable. Which one of the following is true?
(a) P3 is decidable if P1
is reducible to P3
(b) P3 is undecidable if P3
is reducible to P2
(c) P3 is undecidable if P2
is reducible to P3
(d) P3 is decidable if P3
is reducible to P2¢s
complement
46. Consider the set H of all 3 ´ 3 matrices of the type
where a,b,c,d,e and f are real numbers and
abc 0. under the matrix multiplication operation, the set H is:
(a) a group (b) a
monoid but not a group
(c) a semi group but not a monoid (d)
neither a group nor a semi group
47. Which one of the following graphs is NOT
planar?
(a) G1 (b) G2 (c) G3 (d) G4
48. Consider the following system of equations in
three real variables x x x , and :
2x1 - x2 + 3x3 = 1
3x1 + 2x2
+ 5x3 = 2
-x1 + 4x2 + x3
= 3
The system of equations has
(a) no solution
(b) a unique solution
(c) more than one but a finite number
of solutions
(d) an infinite number of solutions
49. What are the eigen values of the following 2
× 2 matrix?
(a) -1
and 1 (b) 1 and 6 (c) 2 and 5 (d) 4
and -1
50. Let G(x) = =
,
where |x| < 1. What is g(i)?
(a) i (b) i
+ 1 (c) 2i (d) 2i
51. Box P has 2 red
balls and 3 blue balls and box Q has 3 balls and 1 blue ball. A ball is
selected as follows: (i) select a box (ii) choose a ball from the selected box
such that each ball in the box is equally likely to be chosen. The
probabilities of selecting boxes P and Q are 1/3 and 2/3 respectively. Given
that a ball selected in the above process is a red ball, the probability that
it came from the box P is:
(a) 4/19 (b) 5/19 (c) 2/9 (d) 19/30
52. A random bit
string of length n is constructed by tossing a fair coin n times and setting a
bit to 0 or 1 depending on outcomes head and tail, respectively. The
probability that two such randomly generated strings are not identical is:
(a) (b) 1
- (c) (d) 1
-
53. Consider
the machine M:
The language
recognized by M is:
(a) {w Î {a, b} * | every a in w is followed by
exactly two b's}
(b) {w Î {a,b} * | every a in w is followed by at
least two b's}
(c) {w Î {a,b} * | w contains the substring 'abb'}
(d) {w Î {a,b} * | w does not contain 'aa' as a
substring
54. Let Nf
and np denote the classes of languages accepted by non-deterministic
finite automata and non-deterministic push-down automata, respectively. Let Df
and Dp denote the classes of languages accepted by deterministic
finite automata and deterministic push-down automata respectively. Which one of
the following is TRUE?
(a) Df Ì Nf and Dp Ì Np (b) Df
Ì Nf and Dp = Np
(c) Df = Nf and
Dp = Np (d) Df
= Nf and Dp Ì Np
55. Consider the
languages:
and
Which one of the
following statements is FALSE?
(a) L1
Ç L2 is a context-free
language
(b) L1
È L2 is a context-free
language
(c) L1
and L2 are context-free language
(d) L1 Ç L2 is a context sensitive
language
56. Let L1 be a recursive language,
and let L2 be a recursively enumerable but not a recursive language.
Which one of the following is TRUE?
(a) is
recursive and is
recursively enumerable
(b) is
recursive and is
not recursively enumerable
(c) and
are
recursively enumerable
(d) is
recursively enumerable and is
recursive
57. Consider the
languages:
L2 = ,
where # is a special symbol
L3 =
{ww|w Î {0, 1}*}
Which one of the
following is TRUE?
(a) L1
is a deterministic CFL (b) L2 is a
deterministic CFL
(c) L3
is a CFL, but not a deterministic CFL (d) L3 is a
deterministic CFL
58. Consider the
following two problems on undirected graphs:
a : Given G(V,E), does G have an independent
set of size |V| - 4?
b : Given G(V,E), does G have an independent
set of size 5?
Which one of the
following is TRUE?
(a) a is in P and b
is NP-complete (b) a
is NP-complete and b is in P
(c) Both a and b
are NP-complete (d) Both a
and b are in P
59. Consider the
grammar:
E ® E + n | E ´
n | n
For a sentence n
+ n ´ n, the handles in the
right-sentential form of the reduction are:
(a) n, E
+ n and E + n ´ n (b)
n, E + n and E + E ´ n
(c) n, n + n and n + n ´ n (d) n,
E + n and E ´ n
60. Consider the
grammar:
S ® (S) | a
Let the number
of states in SLR (1), LR(1) and LALR(1) parsers for the grammar be n1,
n2 and n3 respectively. The following relationship holds
good:
(a) n1
< n2 < n3 (b) n1 = n3
< n2 (c) n1 = n2 = n3 (d) n1
³ n3 ³ n2
61. Consider line
number 3 of the following C-program.
int
min ( ) { /* Line 1 */
int
I, N; /* Line 2 */
fro
(I =0, I<N, I++); /* Line 3 */
}
Identify the
compiler's response about this line while creating the object-module:
(a) No
compilation error
(b) Only
a lexical error
(c) Only
syntactic errors
(d) Both
lexical and syntactic errors
62. Consider the following circuit involving a
positive edge triggered D FF.
Consider the following timing diagram. Let Ai
represent the logic level on the line a in the i-th clock period
Let A¢ represent the complement of A. The correct
output sequence on Y over the clock periods 1 through 5 is:
(a)
(b)
(a)
(a)
63. The following diagram represents a finite
state machine which takes as input a binary number from the least significant
bit.
Which one of
the following is TRUE?
(a) It
computes 1's complement of the input number
(b) It
computes 2's complement of the input number
(c) It
increments the input number
(d) It
decrements the input number
64. Consider the following circuit.
The flip-flops
are positive edge triggered D FFs. Each state is designated as a two-bit string
Q0 Q1 . Let the initial state be 00. the state transition
sequence is
(a) 00
® 11 ®
01 (b) 00 ® 11
(c) 00 ®
10 ® 01 ®
11 (d) 00 ®
11 ® 01 ®
10
65. Consider a three
word machine instruction ADD A[R0], @B
The first
operand (destination) "A[R0]" uses indexed addressing mode with R0 as
the index register. The second operand (source) "@B" uses indirect
addressing mode. A and B are memory addresses residing at the second and the
third words, respectively. The first word of the instruction specifies the
opcode, the index register designation and the source and destination
addressing modes.
During execution
of ADD instruction, the two operands are added and stored in the destination
(first operand).
The number of
memory cycles needed during the execution cycle of the instruction is:
(a) 3 (b) 4 (c) 5
(d) 6
66. Match each of the
high level language statements given on the left hand side with the most
natural addressing mode from those listed on the right hand side.
(1) A[I]
= B[J]; (a) Indirect
addressing
(2) while
(*A++); (b) Indexed addressing
(3) int
temp =*x; (c) Auto increment
(a) (1,
c), (2,b), (3,a) (b) (1, a), (2,c),
(3,b)
(c) (1,
b), (2,c), (3,a) (d) (1, a), (2,b),
(3,c)
67. 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.
(a) 10, 17 (b) 10,
22 (c) 15, 17 (d) 5, 17
68. A 5 stage pipelined CPU has the following
sequence of stages:
IF -
Instruction fetch from instruction memory.
RD - Instruction
decode and register read.
EX - Execute:
ALU operation for data and address computation.
MA
- Data memory access œ
for write access, the register read at RD state is used.
WB - Register
write back.
Consider the following sequence of
instructions:
I1 : L R0, loc 1; R0 <= M[loc1]
I2 : A R0, R0 1; R0 <= R0 + R0
I3 : S R2, R0 1; R2 <= R2 - R0
Let each stage
take one clock cycle. What is the number of clock cycles taken to complete the
above sequence of instructions starting from the fetch of I1 ?
(a) 8 (b) 10
(c) 12 (d) 15
69. A device with
data transfer rate 10 KB/sec is connected to a CPU. Data is transferred
byte-wise. Let the interrupt overhead be 4 sec. The byte transfer time between
the device interfaces register and CPU or memory is negligible. What is the
minimum performance gain of operating the device under interrupt mode over
operating it under program-controlled mode?
(a) 15 (b) 25
(c) 35 (d) 45
70. Consider a disk drive with the following
specifications:
16 surfaces, 512
tracks/surface, 512 sectors/track, 1 KB/sector, rotation speed 3000 rpm. The
disk is operated in cycle stealing mode whereby whenever one 4 byte word is
ready it is sent to memory; similarly, for writing, the disk interface reads a
4 byte word from the memory in each DMA cycle. Memory cycle time is 40 nsec.
The maximum percentage of time that the CPU gets blocked during DMA operation is:
(a) 10 (b) 25
(c) 40 (d) 50
71. Suppose n
processes, P1, …. Pn share m identical resource units,
which can be reserved and released one at a time. The maximum resource
requirement of process Pi is si , where s >0. Which
one of the following is a sufficient condition for ensuring that deadlock does
not occur?
(a) "i, si < m (b) "i, si < n
(c) (d)
72. Consider the following code fragment:
if (fork () ==0)
{ a = a + 5; printf("%d,%d\n",
a, &a); }
else { a = a –5;
printf("%d, %d\n", a, &a); }
Let u, be the
values printed by the parent process, and x,y be the values printed by the
child process. Which one of the following is TRUE?
(a) u = x
+ 10 and = y (b) u = x + 10 and is y
(c) u + 10 = x and = y (d)
u + 10 = x and y
73. 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:
(a) 4 (b) 6
(c) 7 (d) 9
74. Suppose the round
trip propagation delay for a 10 Mbps Ethernet having 48-bit jamming signal is
46.4 s. The minimum frame size is:
(a) 94 (b) 416
(c) 464 (d) 512
75. Let E1
and E2 be two entities in an E/R diagram with simple single-valued
attributes. R1 and R2 are two relationships between E1
and E2 , where R1 is one-to-many and R2 is
many-to-many. R1 and R2 do not have any attributes of
their own. What is the minimum number of tables required to represent this
situation in the relational model?
(a) 2 (b) 3
(c) 4 (d) 5
76. The following table has two attributes A and
C where A is the primary key and C is the foreign key referencing a with
on-delete cascade.
A
|
C
|
2
|
4
|
3
|
4
|
4
|
3
|
5
|
2
|
7
|
2
|
9
|
5
|
6
|
4
|
The set of all
tuples that must be additionally deleted to preserve referential integrity when
the tuple (2,4) is deleted is:
(a) (3,4) and (6,4) (b) (5,2)
and (7,2)
(c) (5,2), (7,2) and (9,5) (d) (3,4),
(4,3) and (6,4)
77. The relation book
(title,price) contains the titles and prices of different books. Assuming that
no two books have the same price, what does the following SQL query list?
select title
from book as B
where (select count(*)
from book as T
where
T.price>B.price)<5
(a) Titles
of the four most expensive books (b) Title of the fifth most
inexpensive book
(c) Title
of the fifth most expensive book (d) Titles of the five most
expensive books
78. 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?
(a) AE, BE (b)
AE, BE, DE
(c)
AEH, BEH, BCH (d) AEH, BEH, DEH
Common Data
for questions 79 and 80:
Consider the following data
path of a CPU. The
ALU, the bus and all the registers in the data path are of identical size. All
operations including incrementation of the PC and the GPRs are to be carried
out in the ALU. Two clock cycles are needed for memory read operation œ the
first one for loading address in the MAR and the next one for loading data from
the memory bus into the MDR.
79. The instruction "add
R0, R1" has the register transfer interpretation R0<= R0+R1. The
minimum number of clock cycles needed for execution cycle of this instruction
is:
(a) 2 (b) 3
(c) 4 (d) 5
80. The instruction "call
Rn, sub" is a two word instruction. Assuming that PC is incremented during
the fetch cycle of the first word of the instruction, its register transfer
interpretation is
Rn<= PC+1;
PC<=M[PC];
The minimum
number of CPU clock cycles needed during the execution cycle of this
instruction is:
(a) 2 (b) 3
(c) 4 (d) 5
Linked Answer
Questions: Q.81a to Q.85b carry two marks each.
Statement for
Linked Answer Questions 81a & 81b:
Consider the following C-function:
double foo (int n) {
int i;
double sum;
if (n==0) return 1.0;
else {
sum = 0.0;
for (i =0; i<n; i++)
sum +=foo(i);
return sum;
} }
81a. The space complexity of the above function is:
(a) O(1) (b) O(n)
(c) O(n!) (d) O(nn)
81b. Suppose we modify the above function foo() and
store the values of foo(i), 0<=I<n , as and when they are computed. With
this modification, the time complexity for function foo() is significantly
reduced. The space complexity of the modified function would be:
(a) O(1) (b) O(n) (c) O(n2) (d) O(n!)
Statement for
Linked Answer Questions 82a & 82b:
Let s and t be
two vetices in a undirected graph G=(V,E) having distinct positive edge
weights. Let [X,Y] be a partition of V such that s X and T Y. Consider the edge
e having the minimum weight amongst all those edges that have one vertex in X
and one vertex in Y.
82a. The edge e must definitely belong to:
(a) the minimum weighted spanning
tree of G
(b) the weighted shortest path from s
to t
(c) each path from s to t
(d) the weighted longest path from s
to t
82b. Let the weight of an edge e denote the
congestion on that edge. The congestion on a path is defined to be the maximum
of the congestions on the edges of the path. We wish to find the path from s to
t having minimum congestion. Which one of the following paths is always such a
path of minimum congestion?
(a) a path from s to t in the minimum
weighted spanning tree
(b) a weighted shortest path from s
to t
(c) an Euler walk from s to t
(d) a Hamiltonian path from s to t
Statement for
Linked Answer Questions 83a & 83b:
Consider the following expression
grammar. The semantic rules for expression evaluation are stated next to each
grammar production.
E ® number E.val =
number.val
| E '+' E E(1) ×
val = E(2) × val + E(3)
× val
| E '´' E E(1) ×
val = E(2) × val ´
E(3) × val
83a. The above grammar
and the semantic rules are fed to a yacc tool (which is an LALR(1) parser
generator) for parsing and evaluating arithmetic expressions. Which one of the
following is true about the action of yacc for the given grammar?
(a) It
detects recursion and eliminates recursion
(b) It detects
reduce-reduce conflict, and resolves
(c) It detects
shift-reduce conflict, and resolves the conflict in favor of a shift over a
reduce action.
(d) It detects
shift-reduce conflict, and resolves the conflict in favor of a reduce over a
shift action.
83b. Assume the
conflicts in Part (a) of this question are resolved and an LALR(1) parser is
generated for parsing arithmetic expressions as per the given grammar. Consider
an expression 3 ´ 2 + 1. What
precedence and associativity properties does the generated parser realize?
(a) Equal
precedence and left associativity; expression is evaluated to 7
(b) Equal
precedence and right associativity; expression is evaluated to 9
(c) Precedence
of '×' is higher than that of '+', and both operators are left associative;
expression is evaluated to 7
(d) Precedence
of '+' is higher than that of '×', and both operators are left associative;
expression is evaluated to 9
Statement for
Linked Answer Questions 84a & 84b:
We are given 9 tasks T1, T2,
…. T9. The execution of each task requires one unit of time. We can
execute one task at a time. Each task Ti has a profit Pi
and a deadline di. Profit Pi is earned if the task is
completed before the end of the unit
of time.
Task
|
T1
|
T2
|
T3
|
T4
|
T5
|
T6
|
T7
|
T8
|
T9
|
Profit
|
15
|
20
|
30
|
18
|
18
|
10
|
23
|
16
|
25
|
Deadline
|
7
|
2
|
5
|
3
|
4
|
5
|
2
|
7
|
3
|
84a. Are all tasks
completed in the schedule that gives maximum profit?
(a) All
tasks are completed (b) T1 and T6
are left out
(c) T1
and T8 are left out (d) T4
and T6 are left out
84b. What is the
maximum profit earned?
(a) 147 (b) 165 (c) 167
(d) 175
Statement for
Linked Answer Questions 85a & 85b:
Consider the following floating-point format.
Mantissa is a pure fraction in sign-magnitude form.
85a. The decimal number
0.239 × 213 has the
following hexadecimal representation (without normalization and rounding off):
(a) 0D 24 (b) 0D
4D (c) 4D 0D (d) 4D 3D
85b. The normalized
representation for the above format is specified as follows. The mantissa has
an implicit 1 preceding the binary (radix) point. Assume that only 0's are
padded in while shifting a field. The normalized representation of the above
number (0.239 ´ 213) is:
(a) 0A 20 (b) 11
34 (c) 49 DO (d) 4A E8
End of Question Papers