Kotlin Basic Quiz

Welcome to your Kotlin Basic Questions

Name

In Kotlin, which collection type represents an ordered list of elements?

Array

Map

Set

List

None

Given the following Kotlin program, what will be the value of max?

val num1 = 10
val num2 = 25
val num3 = 15
val max = if (num1 >= num2 && num1 >= num3) num1
else if (num2 >= num1 && num2 >= num3) num2
else num3

None

Which Kotlin feature helps prevent null pointer exceptions?

Unicorn operator (->>)

Star operator (*)

Arrow operator (->)

Elvis operator (?:)

None

What is the Kotlin equivalent of a "for loop" in other programming languages?

foreach loop

repeat loop

for-in loop

while loop

None

What is the output of the following Kotlin program?

fun main() { 
 var sum = 0
 for (i in 1..10) {
 sum += i
 } 
 println(sum) 
}

None

Given the following Kotlin program, what will be the value of result?

val x = 5
val y = 3
val result = x * y

None

In Kotlin, what is the purpose of the "fun" keyword?

It defines a new data type

It declares a function

It specifies a variable's data type

It stands for "funny"

None

How can you define a read-only property in Kotlin?

Using the "val" keyword

Using the "var" keyword

Using the "readonly" keyword

Using the "get" keyword

None

In Kotlin, which keyword is used to declare a variable that cannot be reassigned?

let

const

val

var

None

10.

What does the following Kotlin program do?

fun main() {
 var n = 10
 var factorial = 1
 while (n > 0) {
 factorial *= n
 n--
 }
 println(factorial)
}

Calculates the factorial of 10.

Prints the numbers from 10 to 1 in reverse order.

Prints the first 10 prime numbers.

Calculates the sum of the first 10 numbers.

None

11.

What is the output of the following Kotlin program?

fun main() {
 var fib1 = 0
 var fib2 = 1
 for (i in 1..10) {
 print("$fib1, ")
 val next = fib1 + fib2
 fib1 = fib2
 fib2 = next
 }
}

0, 1, 1, 2, 3, 5, 8, 13, 21, 34,

This program will not compile.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9,

1, 1, 2, 3, 5, 8, 13, 21, 34, 55,

None

12.

What is the entry point of a Kotlin program?

run() method

start() function

execute() function

main() function

None

13.

What is the output of the following Kotlin program?

fun main() {
 val numbers = arrayOf(1, 2, 3, 4, 5)
 val sum = numbers.reduce { acc, num -> acc + num }
 println(sum)
}

120

None

14.

How do you declare a nullable variable in Kotlin?

Using the # symbol

Using the * symbol

Using the ? operator

Using the ! operator

None

15.

What is the output of the following Kotlin program?

fun main() {
 var a = 5
 var b = 10
 a = b.also { b = a }
 println("After swapping: a = $a, b = $b")
}

After swapping: a = 10, b = 5

This program will not compile.

After swapping: a = 0, b = 0

After swapping: a = 5, b = 10

None

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