Collection size and emptiness checks in Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the list is empty.

Kotlin

if (myList.[1]()) {
    println("List is empty")
}

Drag options to blanks, or click blank then click option'

AisEmpty

Bcount

Csize

DisNotEmpty

Attempts:

3 left

💡 Hint

Common Mistakes

Using size == 0 instead of isEmpty()

Using isNotEmpty() which checks the opposite

The isEmpty() function returns true if the collection has no elements.

2fill in blank

medium

Complete the code to check if the list has exactly 3 elements.

Kotlin

if (myList.[1] == 3) {
    println("List has 3 elements")
}

Drag options to blanks, or click blank then click option'

Acapacity

Bcount

Clength

Dsize

Attempts:

3 left

💡 Hint

Common Mistakes

Using length which is for arrays or strings

Using capacity which is unrelated

The size property gives the number of elements in the collection.

3fill in blank

hard

Fix the error in the code to check if the list is not empty.

Kotlin

if (myList.[1]()) {
    println("List has elements")
}

Drag options to blanks, or click blank then click option'

AhasElements

BisNotEmpty

CnotEmpty

DisEmpty

Attempts:

3 left

💡 Hint

Common Mistakes

Using isEmpty() which checks the opposite

Using non-existent functions like notEmpty or hasElements

The isNotEmpty() function returns true if the collection has one or more elements.

4fill in blank

hard

Fill both blanks to create a map of words to their lengths, but only for words longer than 3 characters.

Kotlin

val lengths = words.filter { word -> word.length > 3 }.associate { word -> [1] to [2] }

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Aword

Bword.length

Cword.size

Dlength

Attempts:

3 left

💡 Hint

Common Mistakes

Using word.size which is not a valid property for String

Using 'length' as a variable instead of word.length

We map each word to its length property for words longer than 3 characters.

5fill in blank

hard

Fill all three blanks to create a filtered list of words with length greater than 4, then map to their uppercase forms.

Kotlin

val result = words.filter { it.[1] > [2] }.map { it.[3]() }

Drag options to blanks, or click blank then click option'

Alength

B4

Cuppercase

Dsize

Attempts:

3 left

💡 Hint

Common Mistakes

Using size instead of length for string length

Using uppercase without parentheses

We filter words where length is greater than 4, then map each word to its uppercase form using uppercase().