Integer arithmetic

Question 1

What does the println() statement implicitly do with numeric variables in Java?
a) Treats them as strings
b) Adds them without conversion
c) Ignores them in the output
d) Converts them into binary format

Answer 1

a) Treats them as strings

Question 2

What is the correct output of System.out.println(intNumA + " + " + intNumB + " = " + intNumA + intNumB); if intNumA is 5 and intNumB is 3?
a) 5 + 3 = 53
b) 5 + 3 = 8
c) 5 + 3 = 15
d) 5 + 3 = 1

Answer 2

a) 5 + 3 = 53

Question 3

How can we correct the output of System.out.println(intNumA + " + " + intNumB + " = " + intNumA + intNumB); to produce the correct sum of 8?
a) Add parentheses around intNumA + intNumB
b) Add a semicolon after intNumA
c) Use a separate println statement for intNumA and intNumB
d) Convert intNumA and intNumB to strings before addition

Answer 3

a) Add parentheses around intNumA + intNumB

Question 4

In binary, how is the number 5 represented?
a) 101
b) 011
c) 110
d) 111

Answer 4

a) 101

Question 5

What will be the output of add(5, 3) in the add() method?
a) 8
b) 15
c) 5
d) 3

Answer 5

a) 8

Question 6

What is unit testing in software development?
a) Testing individual parts of an application
b) Testing the whole application only once
c) Testing only the main method
d) Testing only arithmetic operations

Answer 6

a) Testing individual parts of an application

Question 7

What does the assertEquals method in JUnit do?
a) Checks if two values are equal
b) Runs the code twice
c) Imports a JUnit package
d) Highlights syntax errors

Answer 7

a) Checks if two values are equal

Question 8

In the add() method test, why does assertEquals(8, MathExamples.add(5,3)); pass?
a) Because add(5, 3) returns 8
b) Because add(5, 3) returns 10
c) Because add(5, 3) returns 5
d) Because add(5, 3) throws an error

Answer 8

a) Because add(5

Question 9

What is the main purpose of including JUnit dependency in the Maven pom.xml file?
a) To allow unit testing with JUnit
b) To compile the code only
c) To handle arithmetic errors
d) To create classes automatically

Answer 9

a) To allow unit testing with JUnit

Question 10

In Java, which symbol is used for multiplication?
a) *
b) x
c) X
d) ^

Answer 10

a) *

Question 11

What is the output of subtract(5, 3) if implemented correctly?
a) 2
b) 8
c) -2
d) 15

Answer 11

a) 2

Question 12

What does the division operator (/) return when dividing two integers in Java?
a) Only the whole number quotient
b) Both quotient and remainder
c) Only the remainder
d) The result in decimal form

Answer 12

a) Only the whole number quotient

Question 13

If divide(8, 2) is called in a method, what result should be expected?
a) 4
b) 3
c) 8
d) 6

Answer 13

a) 4

Question 14

What will System.out.println(5 + " ÷ " + 3 + " = " + divide(5,3)); output, assuming divide(5, 3) is 1?
a) 5 ÷ 3 = 1
b) 5 ÷ 3 = 1.6667
c) 5 ÷ 3 = 2
d) 5 ÷ 3 = 8

Answer 14

a) 5 ÷ 3 = 1

Question 15

What does the modulo operator (%) return in Java?
a) The remainder of division
b) The quotient of division
c) The sum of numbers
d) The subtraction result

Answer 15

a) The remainder of division

Question 16

What is the output of modulo(5, 3) if correctly implemented?
a) 2
b) 1
c) 3
d) 5

Answer 16

a) 2

Question 17

What will MathExamples.exponent(5, 3) output if the exponent method is implemented correctly?
a) 125
b) 15
c) 8
d) 27

Answer 17

a) 125

Question 18

What library function does Java use for exponentiation, as there is no native operator?
a) Math.pow()
b) Math.exp()
c) Math.sqrt()
d) Math.pow2()

Answer 18

a) Math.pow()

Question 19

What is Test Driven Development (TDD)?
a) Writing tests before writing the method code
b) Testing code only after project completion
c) Writing code without any tests
d) Writing all tests in a single file

Answer 19

a) Writing tests before writing the method code

Question 20

What is the purpose of adding @Test before a method in JUnit?
a) To mark it as a JUnit test method
b) To create a new package
c) To throw an error in the code
d) To add extra assertions automatically

Answer 20

a) To mark it as a JUnit test method