IncludeHelp_logo
Skip Navigation Links

Home » MCQs

Scala Multiple-Choice Questions (MCQs)

Scala, the short form of Scalable language developed by Martin Odersky in 2003. Scala is a general-purpose programming language that supports both object-oriented as well as a functional programming paradigms.

Scala Programming MCQs: This section contains multiple-choice questions and answers on the Scala programming language. It will help the students to test their skills and prepare well for their exams.

List of Scala MCQs

1. Scala programming language was developed by -

  1. James Gosling
  2. Martin Odersky
  3. Dennis MacAlistair Ritchie
  4. Guido van Rossum

Answer: B) Martin Odersky

Explanation:

Scala is a programming language developed by Martin Odersky. It came into the market in 2003. [Read more: Overview of Scala]

Discuss this Question

2. What is the paradigm of the Scala programming language?

  1. Object-oriented
  2. Statically Types
  3. Functional
  4. All of the above

Answer: D) All of the above

Explanation:

Scala is a modern multi-paradigm programming language designed to express common programming patterns in a concise, elegant, and type-safe way. It seamlessly integrates features of object-oriented and functional languages.

Discuss this Question

3. Scala stands for ___.

  1. Scalable language
  2. Scripted advanced language
  3. Sequential language
  4. None

Answer: A) Scalable language

Explanation:

Scala stands for Scalable language.

Discuss this Question

4. Which of the following is not a feature of Scala?

  1. Type inference
  2. Lazy Computation
  3. High order function
  4. None of the above

Answer: D) None of the above

Explanation:

Some common features of Scala are,

  • It runs on a JVM but the compiler is different.
  • Integrates Features of both Object-Oriented Programming and Functional Programming.
  • Lazy Computation increases performance, the expression evaluates only when its evaluation is required.
  • Immutability: it means the value of data cannot be changed by default.
  • Case Classes and Pattern Matching.
  • Type Interface: It recognizes data type and functions return type itself.
  • Concurrency Control: Scala Provide concurrency control using the actor model.
  • High Order Function: A function that works on another function.

Discuss this Question

5. Is Java required before installing Scala on the system?

  1. Yes
  2. No

Answer: A) Yes

Explanation:

Yes. Before you start installing Scala on your machine, you must have Java 1.8 or greater installed on your computer.

Discuss this Question

6. The semicolon (;) in Scala is -

  1. Necessary, failing to write will not mark the end of line
  2. Not required, it is treated as a character
  3. Optional, end of the line does not require ;
  4. None of these

Answer: C) Optional, end of the line does not require ;

Explanation:

If the programmer puts a semicolon at the end of the line it's ok and if no semicolon is present even then too the compiler does not throw any error. Read more: Semicolons in Scala

Discuss this Question

7. The Scala compiler starts executing from -

  1. The first line of code
  2. main() method
  3. main class
  4. End of code

Answer: B) main() method

Explanation:

The entry point of the flow of code in Scala is the main() method. There is no specific object required, it can be present in any object of the program.

Discuss this Question

8. Which of the following are not present in Scala?

  1. Closures
  2. Monads
  3. Traits
  4. None

Answer: D) None

Explanation:

All the above features are present in Scala.

Discuss this Question

9. The correct syntax for creating Single line comments in Scala is,

  1. //
  2. <!-- -- >
  3. /* */
  4. %%

Answer: A) //

Explanation:

// is used to create a single line comment in Scala. /*...*/ is used to create multiline comments in Scala.

Discuss this Question

10. The correct output of the following code is,

object MyClass {
    def main(args: Array[String]) {
        var i,j=0
        for(i <- 0 to 3){
            for(j <- 0 until 2){
                if(i + j == 3){
                    print((i*j)+"\t")
                }
            }
        }
    }
}
  1. 3 3
  2. 2 0
  3. 0 2
  4. 1 1

Answer: B) 2 0

Explanation:

In a nested loop, we will print values, The first iteration is 2, 1 and the second is 3, 0.

Discuss this Question

11. Which of these is not a primary data type in Scala -

  1. Integer
  2. String
  3. Array
  4. Char

Answer: C) Array

Explanation:

Array is not a primary data in Scala.

Discuss this Question

12. The size of integer data type in Scala is -

  1. 256 bits
  2. 4 bits
  3. 32 bits
  4. 64 bits

Answer: C) 32 bits

Explanation:

An Integer is a 32-bit value and is central to any numeric representation in Scala.

Discuss this Question

13. Why is Double better than Float values?

  1. It can store double-precision values providing more accurate data to be stored.
  2. It stores 64 bits values instead of 32 bits from a float.
  3. Float Values are better
  4. Both A and B

Answer: D) Both A and B

Explanation:

The Double type is more precise than Float type and can store 64 bits, double of the number of bits float can store. Double is more precise and for storing large numbers, we prefer double over float.

Discuss this Question

14. Which class is the super-class of all classes in Scala?

  1. Ref
  2. AnyRef
  3. Any
  4. AnyVar

Answer: C) Any

Explanation:

Any is the superclass of all classes, also called the top class. any class is inherited by all classes in Scala.

Discuss this Question

15. Which type class does not inherit AnyVar?

  1. Char
  2. Int
  3. Float
  4. Pointer

Answer: D) Pointer

Explanation:

All the other values inherit AnyVar class.

Discuss this Question

16. The correct output of the below code block is -

object MyClass {
    def main(args: Array[String]) {
        var a : Float = 454.32138988f
        var b : Double = a;
        
        printf("a = " + a + "\t b = " + b)
    }
}
  1. a = 454.32138988 b = 454.32138988152344
  2. a = 454.32138 b = 454.3213806152344
  3. a = 454.32138 b = 454.32138
  4. error

Answer: A) a = 454.32138988 b = 454.32138988152344

Discuss this Question

17. Default values of string type when it is not initialized -

  1. 0
  2. Null
  3. None
  4. " "

Answer: B) Null

Explanation:

The default value of the string variable is Null.

Discuss this Question

18. Which type in Scala is a subtype of all types -

  1. Int
  2. Ref
  3. Boolean
  4. Nothing

Answer: D) Nothing

Explanation:

In Scala, Nothing is treated as the subtype of all types.

Discuss this Question

19. Statement returned by function when no values are returned in Scala -

  1. No value
  2. Unit
  3. Int
  4. None of these

Answer: B) Unit

Explanation:

Statement returned by function when no values are returned in Scala is Unit.

Discuss this Question

20. In Scala, can you return two values?

  1. Yes
  2. No

Answer: A) Yes

Explanation:

In Scala, Options are used to return two instances.

Discuss this Question

21. What is the range defined by the below statement -

range(13, 17, 2)
  1. 13 14 15 16 17
  2. 13 14 15 16
  3. 13 15
  4. 13 15 17

Answer: C) 13 15

Explanation:

The range will exclude the last value and iterate by 2 for each value.

Discuss this Question

22. Which is not a Scala method for printing text on the screen?

  1. print()
  2. printf()
  3. printl()
  4. println()

Answer: C) printl()

Explanation:

The printl() is not a valid Scala method. All three above mentioned methods are used for printing.

Discuss this Question

23. What is the output of following code?

val i = 43
i = 231
printf(i)
  1. 231
  2. 43
  3. 0
  4. Error

Answer: D) Error

Explanation:

The val keyword defines immutable values in Scala. [Read more: Scala Literal, Variables and Data Type]

Discuss this Question

24. Literals in Scala are ___.

  1. Name of the variables
  2. A literal is a value that can be assigned to a variable
  3. The type of the values
  4. None of these

Answer: B) A literal is a value that can be assigned to a variable

Explanation:

Any constant value which can be assigned to the variable is called as literal

Discuss this Question

25. Based on Type Casting, which of these conversions is lossy or invalid?

  1. Character -> Float
  2. Float -> Long
  3. Short -> Integer
  4. Integer -> Double

Answer: B) Float -> Long

Explanation:

Float - > Long is not a valid type casting. [Refer diagram given here: Scala Type Casting]

Discuss this Question

26. Which type of typecasting is done by the compiler?

  1. Implicit Conversion
  2. Explicit Conversion
  3. Instance conversion
  4. None of these

Answer: A) Implicit Conversion

Explanation:

In the implicit type casting of type – the compiler itself cast the type of the value/variable.

Discuss this Question

27. Explicit Conversion is -

  1. Done by the compiler itself
  2. Defined by the user
  3. Both A and B
  4. None of the above

Answer: B) Defined by the user

Explanation:

The explicit type conversion is a user-defined type conversion i.e., the user/programmer will decide the final data type of the value/variable.

Discuss this Question

28. The getClass() method is used to -

  1. Extract the class of the given number
  2. Extract the value of the variable
  3. Extract the memory location of the variable
  4. All of the Above

Answer: A) Extract the class of the given number

Explanation:

The getClass() method is used to return the class of the given number.

Discuss this Question

29. Converting Character to Integer will return -

  1. Error
  2. Random integer value
  3. ASCII value of the character
  4. None of the above

Answer: C) ASCII value of the character

Explanation:

Converting a character to integer will return the ASCII value of the character.

Discuss this Question

30. Which Scala keyword is used to initialize a variable?

  1. int
  2. var
  3. value
  4. None

Answer: B) var

Explanation:

Scala variables are created using the var keyword.

Discuss this Question

31. Lazy initialization is -

  1. Creating variables using the lazy keyword
  2. Done only on immutable variables
  3. Calculated at its first access
  4. All of the above

Answer: D) All of the above

Explanation:

Lazy initialization variables are those variables that are calculated when the first time they are accessed. Scala mutable variables cannot be lazy.

Discuss this Question

32. The total number of keywords in Scala are -

  1. 45
  2. 34
  3. 39
  4. 52

Answer: C) 39

Explanation:

There are in total 39 keywords present in Scala. [Learn more: Scala Keywords]

Discuss this Question

33. Which of these is not a keyword in Scala?

  1. int
  2. var
  3. forsome
  4. package

Answer: A) int

Explanation:

"int" is not a Scala keyword.

Discuss this Question

34. Using a keyword as a value will lead to -

  1. Error
  2. Compile with the NULL value
  3. Warning
  4. None of these

Answer: A) Error

Explanation:

The compiler will throw an error if we try to use keywords as identifiers.

Discuss this Question

35. Is 'sealed' a keyword in Scala -

  1. Yes
  2. No

Answer: A) Yes

Explanation:

Yes, the sealed is a keyword in Scala.

Discuss this Question

36. Identifiers in Scala are names given to -

  1. Classes or objects
  2. Methods
  3. Objects
  4. All of these

Answer: D) All of these

Explanation:

Identifiers in a programming language are the names given to a class, method, variable, or object to identify them in the program.

Discuss this Question

37. Which of these is not a type of identifier -

  1. Alphanumeric identifier
  2. Operator identifier
  3. Literal identifier
  4. Value identifier

Answer: D) Value identifier

Explanation:

In Scala, we have 4 different types of identifiers defined. They are:

  1. Alphanumeric Identifiers
  2. Operator Identifiers
  3. Mixed Identifiers
  4. Literal Identifiers

Discuss this Question

38. Is the following identifier valid?

12Scala_3
  1. Yes
  2. No

Answer: B) No

Explanation:

"12Scala_3" is not a valid identifier. The identifiers must be started either an alphabet or an underscore (_).

Discuss this Question

39. Literal Identifier is -

  1. String literal used as an identifier in Scala
  2. Value literal used as an identifier in Scala
  3. Numeric literal used as an identifier in Scala
  4. None

Answer: A) String literal used as an identifier in Scala

Discuss this Question

40. The correct output of the following code is -

object myObject {
    def main(args: Array[String]) {
        var _value1 = 54
        var 3value_2 = 65
        
        println("The sum of two values is " + (_value1 + value_2))
    }
}
  1. 54
  2. Error
  3. 119
  4. 65

Answer: B) Error

Explanation:

The second variable is 3value_2 which is not an valid identifier and in the expression, we are using value_2 which is not defined in the above code.

Output:

jdoodle.scala:4: error: invalid literal number
        var 3value_2 = 65
            ^
jdoodle.scala:6: error: '=' expected.
        println("The sum of two values is " + (_value1 + value_2))
^

Discuss this Question

41. Which variable in Scala can save memory while declaring variables?

  1. Mutable variables
  2. Lazy Variables
  3. Inherited Variables
  4. None of these

Answer: B) Lazy Variables

Explanation:

Using the lazy keyword, you can halt the initialization of the variable until the time it is first used or accessed in the code.

Discuss this Question

42. How many types of operators are present in Scala?

  1. 5
  2. 2
  3. 6
  4. 8

Answer: A) 5

Explanation:

There are 5 types of operators in Scala, they are:

  • Arithmetic Operators
  • Relational Operators
  • Logical Operators
  • Bitwise Operators
  • Assignment Operators

Discuss this Question

43. Logical operators in Scala are used to -

  1. Perform a comparison of values
  2. Perform logical operation on the boolean value
  3. Return a value
  4. None

Answer: B) Perform logical operation on the boolean value

Explanation:

Logical operators, logical-or (|| and | ) and logical-and (&& and &) take Boolean operands and evaluate to a Boolean result.

Discuss this Question

44. What is the use of the "&=" operator in Scala -

  1. Bitwise operator
  2. Arithmetic operator
  3. Bitwise Assignment operator
  4. None of these

Answer: C) Bitwise Assignment operator

Explanation:

The bitwise AND assignment operator (&=) uses the binary representation of both operands, does a bitwise AND operation on them and assigns the result to the variable.

Discuss this Question

45. Find the result of the following code block -

(3 + 4 * 5) >>>  1
  1. 43
  2. 11
  3. 12
  4. 120

Answer: B) 11

Discuss this Question

46. Relation operators are -

  1. Return a relative value
  2. Used to define the comparison between the two operators
  3. Create new values based on the relation
  4. None of these

Answer: B) Used to define the comparison between the two operators

Explanation:

Relation operators are used to check whether the two operands are equal or not and returns true if they are equal

Discuss this Question

47. What is the symbolic operator in Scala?

  1. Predefined sets that can handle a specific task
  2. Are reserved to a specific use
  3. Symbols that have a specific task that they perform when called in a Scala program
  4. All of these

Answer: D) All of these

Explanation:

The symbolic operators in Scala are symbols that have a specific task that they perform when called in a Scala program. Scala library defines a lot of symbols that can be used while programming in Scala.

Discuss this Question

48. The final keyword in Scala is used to -

  1. Define a variable whose value cannot be further changed
  2. Create a new variable
  3. Special inaccessible value in Scala
  4. None of these

Answer: A) Define a variable whose value cannot be further changed

Explanation:

In Scala, Final is a keyword and used to impose restriction on super class or parent class through various ways.

Discuss this Question

49. A final method can be applied on?

  1. Variables
  2. Classes
  3. Functions
  4. All of these

Answer: D) All of these

Explanation:

The final method can be used with variables, functions as well as classes.

Discuss this Question

50. What is the scope of a local variable in Scala?

  1. Whole program
  2. A method is it declared in
  3. Class/object containing it
  4. All of the above

Answer: B) A method is it declared in

Explanation:

Local variables of methods have scope restricted to that of methods in Scala.

Discuss this Question

51. The output of the following block of code is -

class Student{ 
    var roll = 43; 
    
    def printTotal(){
        var totalMarks = 500
        println(roll)
    }
} 

object MyClass{
	def main(args:Array[String]) {
	    var s1 = new Student
	    println(s1.totalMarks)
	}
}
  1. 500
  2. 43
  3. Error
  4. None of these

Answer: C) Error

Explanation:

totalMarks is a local variable of printTotal() method. Hence, cannot be used outside it.

Discuss this Question

52. Which is valid to method to increase value of variable by one?

  1. a++
  2. ++a
  3. a += 1
  4. All of these

Answer: C) a += 1

Explanation:

The Scala programming language doesn't support unary operators (++ or --). In Scala, the binary operators are used to increment and decrement an integer.

Discuss this Question

53. The output of the following code is -

object MyClass{
	def main(args:Array[String]) {
	    var a = 43
	    a += 4 
	    a -= 3
	    println(a)
	} 
}
  1. 43
  2. 44
  3. 45
  4. All of the above

Answer: B) 44

Discuss this Question

54. Ignored variables are used to -

  1. Create variables without using names
  2. Create blank value variable
  3. Both A and B
  4. None of these

Answer: A) Create variables without using names

Explanation:

When we don't care about variables for constructed entries, we can ignore them using the underscore.

Discuss this Question

55. Wildcard patterns (_) is used to -

  1. Create variables
  2. Create new unmatched patterns
  3. Match the unmatched case
  4. None of these

Answer: C) Match the unmatched case

Explanation:

The wildcard pattern ( _ ) matches any object whatsoever.

Discuss this Question

56. The following code statement will -

import java.util._
  1. import _ method from util library
  2. Error
  3. Import all methods from java.util library
  4. None of these

Answer: C) Import all methods from java.util library

Explanation:

import java.util._ imports all methods from java.util library.

Discuss this Question

57. What are expressions in Scala?

  1. Line of code that compiles to a value
  2. Code block without semicolon
  3. Line of code containing = sign
  4. None of these

Answer: A) Line of code that compiles to a value

Explanation:

The expressions are the line of code that compiles to a value.

Discuss this Question

58. Conditional statement in Scala executes a block of code based on some conditional value?

  1. True
  2. False

Answer: A) True

Explanation:

The above given statement is true.

Discuss this Question

59. Which of these is not a conditional statement in Scala?

  1. if statement
  2. if-else statement
  3. This statement
  4. None of these

Answer: C) This statement

Explanation:

This statement is not a conditional statement in Scala.

Discuss this Question

60. The output of the code block of code is -

var myNumber = 5 ;

if(myNumber > 20)
    print("A");
else if(myNumber > 15)
    print("B");
else
    print("C");
  1. A
  2. B
  3. C
  4. None of these

Answer: C) C

Discuss this Question

61. The do-while loop in Scala is -

  1. Iteration control Loop
  2. Entry control loop
  3. Exit control loop
  4. None of these

Answer: C) Exit control loop

Explanation:

The do-while loop is an exit control loop, where loop body executes before evaluating the test condition.

Discuss this Question

62. The for loop in Scala is -

  1. Iteration control loop
  2. Entry control loop
  3. Exit control loop
  4. None of these

Answer: A) Iteration control loop

Explanation:

The for loop is an iteration control loop.

Discuss this Question

63. The output of the following block of code is -

var myVar = 12; 

print(myVar);

while(myVar <= 10){
    print("*");
    myVar += 2;
}
  1. 12
  2. 12****
  3. 12*
  4. None of these

Answer: A) 12

Discuss this Question

64. 2-D structures in Scala can be looped using -

  1. Nested Loop
  2. Structure
  3. Collection iteration
  4. None of these

Answer: A) Nested Loop

Explanation:

The 2-D structure can be looped using the nested loop.

Discuss this Question

65. Output of the following block of code -

for(i <- 1 to 2){
    for(j <- 1 to 2)
        print("(" + i + "," + j + ")\t")
}
  1. (1,1) (1,1) (1,1) (1,1)
  2. (1,1) (1,2) (2,1) (2,2)
  3. (1,1) (2,2) (1,1) (2,2)
  4. None of these

Answer: B) (1,1) (1,2) (2,1) (2,2)

Discuss this Question

66. The break statement in Scala is imported using -

  1. import scala.util.control._
  2. import scala.break
  3. import control._
  4. None of these

Answer: C) pi()

Explanation:

The break statement in Scala is imported using import scala.util.control._.

Discuss this Question

67. Yield in Scala is used to -

  1. Returns the resultant value of for loop
  2. Stores a variable at each for loop iteration
  3. Used with for loop
  4. All of these

Answer: D) All of these

Explanation:

For each iteration of your for loop, yield generates a value which is remembered by the for loop.

Discuss this Question

68. Can there be multiple counters in a for loop in Scala?

  1. Yes
  2. No

Answer: A) Yes

Explanation:

Yes, there can be multiple counters in a for loop in Scala.

Discuss this Question

69. To create a loop breakable in Scala, do we need to enclose it?

  1. break
  2. loop.breakable
  3. breaks
  4. None of these

Answer: B) loop.breakable

Explanation:

To create a loop breakable in Scala, do we need to enclose it by loop.breakable.

Discuss this Question

70. The default parameters are used when -

  1. No parameter is passed
  2. The extra parameter is passed
  3. Always when the function is called
  4. None of these

Answer: A) No parameter is passed

Explanation:

The default arguments are used when you provide no arguments or only few arguments while calling a function.

Discuss this Question

71. The output of the following block of code is -

object Demo {
    def welcome( a: Int = 54, b: Int = 21 ){
        println(a + b);
    }
    def main(args: Array[String]) {
        welcome(5);
    }
}
  1. 75
  2. 59
  3. 26
  4. 10

Answer: C) 26

Discuss this Question

72. Recursion function is -

  1. A function that calls itself multiple times
  2. Has a loop statement
  3. All of these
  4. None of these

Answer: A) A function that calls itself multiple times

Explanation:

Recursion is the process of defining a problem (or the solution to a problem) in terms of (a simpler version of) itself.

Discuss this Question

73. Which of these can be solved using recursion?

  1. Factorial
  2. Fibonacci
  3. Both A and B
  4. None of these

Answer: C) Both A and B

Explanation:

The both Factorial and Fibonacci series can be extracted using the recursion.

Discuss this Question

74. Method overloading in Scala is?

  1. Creating multiple methods performing the same task
  2. Redefining methods in different ways under the same name
  3. Creating methods differently
  4. All of these

Answer: B) Redefining methods in different ways under the same name

Explanation:

Scala Method overloading is when one class has more than one method with the same name but different signature.

Discuss this Question

75. The output of the following block of code is -

object MyClass {
    def datatype(x:Int){
        println("The parameter is of Integer datatype")    
    }
    
    def datatype(x:Float){
        println("The parameter is of Float data type")    
    } 
    
    def datatype(x:Char){
        println("The parameter is of Character data type")    
    }
    
    def datatype(x: Boolean){
        println("The parameter is of Boolean data type")    
    }
    
    def main(args: Array[String]) {
        
        datatype(4.0f)
    }
}
  1. The parameter is of Boolean data type
  2. The parameter is of Integer data type
  3. The parameter is of Character data type
  4. The parameter is of Float data type

Answer: D) The parameter is of Float data type

Discuss this Question

76. Which statement in Scala is used to create a tail-recursive function -

  1. @newtailRec
  2. @tailRecFunc
  3. @tailRec
  4. @tailrec

Answer: D) @tailrec

Explanation:

The @tailrec is is used to create a tail-recursive function.

Discuss this Question

77. Tail recursion in Scala is -

  1. Initiated from last
  2. Initiated from the first call

Answer: A) Initiated from last

Explanation:

The tail recursion is initiated from the last.

Discuss this Question

78. What is the maximum number of parameters a method can accept?

  1. 32
  2. 64
  3. 128
  4. 255

Answer: D) 255

Explanation:

The number of method parameters is limited to 255 by the definition of a method descriptor.

Discuss this Question

79. Which syntax to pass the variable argument to function in Scala?

  1. (int a, int b, int c, ….)
  2. (a : Int, b : Int, c:Int, …)
  3. (args: String*)
  4. None of these

Answer: C) (args: String*)

Explanation:

The syntax to pass the variable argument to function in Scala is:

(args: String*)

Discuss this Question

80. Can you alter the sequence of parameter passing?

  1. Yes
  2. No

Answer: A) Yes

Explanation:

Yes, you can alter the sequence of parameter passing.

Discuss this Question

81. The output of the following block of code is -

object Demo {
    def sub( a:Int, b:Int ) = {
        println( (a-b) );
    }
    def main(args: Array[String]) {
        sub(b = 5, a = 7);
    }
}
  1. -2
  2. 2
  3. Error
  4. None of these

Answer: B) 2

Explanation:

Named arguments are passed and used.

Discuss this Question

82. Closures in Scala are -

  1. Functions that return multiple values
  2. Functions that can accept variable arguments
  3. Functions that use a value from outside of the function's body
  4. None of these

Answer: C) Functions that use a value from outside of the function's body

Explanation:

The Scala Closures are functions which uses one or more free variables and the return value of this function is dependent of these variable.

Discuss this Question

83. The output of the following block of code will be -

object myObject {

    var multiplier = 5;
    
    def main(args: Array[String]) {
        println(calculator(45));
    }
    
    val calculator = (i:Int) => i * multiplier;
}
  1. 45
  2. 5
  3. Error
  4. 225

Answer: D) 225

Explanation:

The calculator method is a closure.

Discuss this Question

84. Which of these parts of the declaration are not required in the case of parameter less methods?

  1. def keyword
  2. Return type
  3. Parenthesis ()
  4. All of these

Answer: C) Parenthesis ()

Explanation:

Read: Parameterless method in Scala

Discuss this Question

85. Which of these ways of invoking a method are valid in Scala?

  1. Using . operator
  2. Using direct name call by other methods of the same class
  3. Using inheritance
  4. All of these

Answer: D) All of these

Explanation:

All of the above-mentioned methods can be used to invoke a method in Scala.

Discuss this Question

86. Lambda expression stores the value of -

  1. Variable
  2. Constant
  3. Function
  4. None of these

Answer: C) Function

Explanation:

In Scala, the lambda expression stores the value of the function.

Discuss this Question

87. Can Lambda expressions be used on collections in Scala?

  1. Yes
  2. No

Answer: A) Yes

Explanation:

Yes, the lambda expressions can be used on the collections in Scala.

Discuss this Question

88. Ways to define a composite function in Scala are -

  1. Compose keyword
  2. andthen keyword
  3. Passing method to another method
  4. All of these

Answer: D) All of these

Explanation:

There are multiple ways to define the composition of a function. They are,

  1. Using compose Keyword
  2. Using andthen Keyword
  3. Passing method to method

Discuss this Question

89. What is the output of the following block of code -

object myObject { 
	def main(args: Array[String]) { 
		println((  div(mul(452)) ))
	} 
	
	val mul = (a: Int)=> { 
		a * 100
	} 
	
	val div = (a: Int) =>{ 
		a / 500
	} 
}
  1. 45200
  2. 0
  3. 90
  4. Error

Answer: C) 90

Explanation:

Here, functions are used in composition and the result is an integer value that causes the loss in data.

Discuss this Question

90. What is the chopping of string -

  1. Divide the string into two equal halves
  2. Strip off new line characters
  3. Extract substring from a given index
  4. None of these

Answer: B) Strip off new line characters

Explanation:

The string chomp(or chop) function in Scala is used to chop off the end of line characters.

Discuss this Question

91. Unit value in Scala is -

  1. Used as a return statement when no value is returned to it.
  2. The function automatically returns a unit value when no value is returned.
  3. Returned using Unit keyword
  4. All of these

Answer: D) All of these

Explanation:

Read more: How to return the Unit from a Scala function?

Discuss this Question

92. Array in Scala is -

  1. A primary data type
  2. Stream of data from I/O
  3. Linear data structure with a fixed number of elements
  4. All of these

Answer: C) Linear data structure with a fixed number of elements

Explanation:

Array is a linear data structure with a fixed number of elements.

Discuss this Question

93. Which Scala keyword is used to create an array?

  1. Arr
  2. array
  3. Array
  4. All of these

Answer: C) Array

Explanation:

The Array keyword is used to create an array.

Discuss this Question

94. Correct syntax for creating an array in Scala -

  1. var array_name : Array[data_type] = new Array[data_type(size)
  2. var array_name: Array[data_tpye] = new Array(size)
  3. var array_name = Array(element1, elmenet2, element3, ...)
  4. All of these

Answer: D) All of these

Explanation:

Read more: How to print an array in Scala?

Discuss this Question

95. Is array mutable in Scala?

  1. Yes
  2. No

Answer: B) No

Explanation:

To create a mutable array in Scala arrayBuffer is used.

Discuss this Question

96. How to create a mutable array in Scala?

  1. Initializing using the var keyword
  2. Using arrayBuffer
  3. Adding mutable before initialization
  4. All of these

Answer: B) Using arrayBuffer

Explanation:

Read more: ArrayBuffer in Scala (Creating Mutable Arrays)

Discuss this Question

97. Methods which can be used to remove/ delete users from arrayBuffer in Scala?

  1. arrayBuffer.remove()
  2. arrayBuffer.delete()
  3. arrayBuffer.push()
  4. All of these

Answer: A) arrayBuffer.remove()

Explanation:

The Scala method arrayBuffer.remove() is used to remove/delete from arrayBuffer.

Discuss this Question

98. Method used to get the length of array in Scala -

  1. Array.len
  2. length(arr)
  3. arr.size
  4. sizeof(arr)

Answer: C) arr.size

Explanation:

Scala method arr.size is used to get the length of an array.

Discuss this Question

99. List in Scala is -

  1. Primary data structure
  2. The collection that stores data as a string
  3. A collection that stores data in the form of a linked-list
  4. None of these

Answer: C) A collection that stores data in the form of a linked-list

Explanation:

Read more: Scala Lists

Discuss this Question

100. Method used to check if a list is empty in Scala -

  1. list.isEmpty
  2. list.isNull
  3. list.empty
  4. None of these

Answer: a) list.isEmpty

Explanation:

Scala method list.isEmpty is used to check if a list is empty.

Discuss this Question




Comments and Discussions!

Load comments ↻




Top MCQs
Top Programs/Examples
Top Tutorials
About
Student's Section
Subscribe

Copyright © 2024 www.includehelp.com. All rights reserved.