ISRO CS 2020

Question 11

Given that

B(a) means “a is a bear”
F(a) means “a is a fish” and
E(a, b) means “a eats b” 

Then what is the best meaning of

∀x[F(x) ⇒ ∀y(E(y, x) ⇒ B(y))] 

• Every fish is eaten by some bear
• Bears eat only fish
• Every bear eats fish
• Only bears eat fish

Question 12

Following declaration of an array of struct, assumes size of byte, short, int and long are 1, 2, 3 and 4 respectively. Alignment rule stipulates that n-byte field must be located at an address divisible by n. The fields in a struct are not rearranged, padding is used to ensure alignment. All elements of array should be of same size.

Struct complex
  Short s
  Byte b
  Long l
  Int i
End complex
Complex C[10] 

Assuming C is located at an address divisible by 8, what is the total size of C, in Bytes ?

• 150

• 160

• 200

• 240

Question 13

The immediate addressing mode can be used for

1. Loading internal registers with initial values 1.
2. Perform arithmetic or logical operation on data contained in instructions 2.

Which of the following is true ?

• Only 1
• Only 2
• Both 1 and 2
• Immediate mode refers to data in cache

Question 14

Statements associated with registers of a CPU are given. Identify the false statement.

• The program counter holds the memory address of the instruction in execution.

• Only opcode is transferred to the control unit.

• An instruction in the instruction register consists of the opcode and the operand.

• The value of the program counter is incremented by 1 once its value has been read to the memory address register.

Question 15

Which of the following affects the processing power assuming they do not influence each other.

1. Data bus capability 1.
2. Addressing scheme
3. Clock speed 3.

• 3 only
• 1 and 3 only
• 2 and 3 only
• 1, 2 and 3

Question 16

Convert the pre-fix expression to in-fix

–* + ABC* – DE + FG 

• (A – B)*C + (D*E) – (F + G)

• (A + B)*C – (D – E)*(F – G)

• (A + B – C)*(D – E))*(F + G)

• (A + B)*C – (D*E) – (F + G)

• None

Question 17

G is an undirected graph with vertex set {v1, v2, v3, v4, v5, v6, v7} and edge set {v1v2, v1v3, v1v4, v2v4, v2v5, v3v4, v4v5, v4v6, v5v6, v6v7}. A breadth first search of the graph is performed with v1 as the root node. Which of the following is a tree edge ?

• v2v4
• v1v4
• v4v5
• v3v4

Question 18

If the array A contains the items 10, 4, 7, 23, 67, 12 and 5 in that order, what will be the resultant array A after third pass of insertion sort ?

• 67, 12, 10, 5, 4, 7, 23
• 4, 7, 10, 23, 67, 12, 5
• 4, 5, 7, 67, 10, 12, 23
• 10, 7, 4, 67, 23, 12, 5

Question 19

Huffman tree is constructed for the following data: {A, B, C, D, E} with frequency {0.17, 0.11, 0.24, 0.33 and 0.15} respectively. 100 00 01101 is decoded as

• BACE

• CADE

• BAD

• CADD

Question 20

Given the grammar:

s → T * S⏐T
T → U + T⏐U
U → a⏐b 

Which of the following statement is wrong ?

• Grammar is not ambiguous
• Priority of + over * is ensured
• Right to left evaluation of * and + happens
• None of these