Kotlin Basics Quiz

Welcome to your Kotlin Basic Questions

Name

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

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

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

Map

Array

Set

List

What is the entry point of a Kotlin program?

start() function

run() method

execute() function

main() function

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

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

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

This program will not compile.

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

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

const

let

var

val

How do you declare a nullable variable in Kotlin?

Using the ? operator

Using the * symbol

Using the # symbol

Using the ! operator

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

Using the "var" keyword

Using the "val" keyword

Using the "get" keyword

Using the "readonly" keyword

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

while loop

for-in loop

foreach loop

repeat loop

10.

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

11.

In Kotlin, what keyword is used to declare a function?

proc

method

func

fun

12.

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")
}

This program will not compile.

After swapping: a = 5, b = 10

After swapping: a = 0, b = 0

After swapping: a = 10, b = 5

13.

What is the range operator used to create a range of numbers in Kotlin?

14.

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 sum of the first 10 numbers.

Calculates the factorial of 10.

Prints the first 10 prime numbers.

Prints the numbers from 10 to 1 in reverse order.

15.

What is the output of the following Kotlin program?

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

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