Operator precedence in Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to calculate the correct result using operator precedence.

Kotlin

val result = 3 + 4 * [1]

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

A1

B2

C5

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Adding 3 + 4 first, then multiplying by the number.

Ignoring operator precedence and calculating left to right.

The multiplication happens before addition, so 4 * 5 = 20, then 3 + 20 = 23.

2fill in blank

medium

Complete the code to get the correct boolean result using operator precedence.

Kotlin

val isTrue = true || false && [1]

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

Afalse

Btrue

Cnull

Dtrue && false

Attempts:

3 left

💡 Hint

Common Mistakes

Evaluating || before &&.

Using an expression instead of a boolean value.

Logical AND (&&) has higher precedence than OR (||). So false && false = false, then true || false = true.

3fill in blank

hard

Fix the error in the expression by completing the code with the correct operator.

Kotlin

val value = 10 + 5 [1] 3

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

A/

B%

C-

D*

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction (-) or division (/) which changes the result.

Using modulo (%) which is not intended here.

Multiplication (*) has higher precedence than addition (+), so 5 * 3 is calculated first, then added to 10.

4fill in blank

hard

Fill both blanks to create a map of words to their lengths only if length is greater than 3.

Kotlin

val lengths = mapOf([1] to [2]).filter { it.value > 3 }

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

A"apple"

B"banana"

C"apple".length

D"banana".length

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same word for key and length causing confusion.

Not using quotes for string keys.

The map pairs the word "apple" with the length of "apple". Then filter keeps entries with length > 3.

5fill in blank

hard

Fill all three blanks to create a filtered map with uppercase keys and values greater than 4.

Kotlin

val filtered = mapOf([1] to [2]).filter { it.value [3] 4 }

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

A"pear".uppercase()

B5

C>

D"plum".uppercase()

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase strings instead of uppercase.

Using wrong comparison operators like < or ==.

The map has key "PLUM" (uppercase) with value 5. The filter keeps entries where value > 4.