Kotlin Function: Print even numbers from list, Return Unit

Last update on August 27 2025 12:41:24 (UTC/GMT +8 hours)

Write a Kotlin function that takes a list of integers as an argument and prints only the even numbers in the list. The function should return Unit.

Pre-Knowledge (Before you start!)

Basic Kotlin Syntax: Familiarity with writing and running Kotlin programs.
Kotlin Functions: Understanding how to define and call functions in Kotlin.
Unit Type: Awareness that functions without a return value implicitly return Unit in Kotlin.
Lists in Kotlin: Knowledge of working with lists, including iterating through elements.
Modulo Operator: Understanding the modulo operator (%) to check if a number is even or odd.
Conditional Statements: Ability to use if statements to filter elements based on conditions.
Printing Output: Familiarity with the println() function to display output on the screen.

Hints (Try before looking at the solution!)

Define the Function.
Iterate Through the List.
Check for Even Numbers.
Print Even Numbers.
Call the Function.
Test with Different Lists.
Common Errors to Avoid:
- Forgetting the modulo operator.
- Misplacing if conditions.
- Unnecessarily adding a return statement.

Sample Solution:

Kotlin Code:

fun printEvenNumbers(numbers: List<Int>): Unit {
    for (number in numbers) {
        if (number % 2 == 0) {
            println(number)
        }
    }
}

fun main() {
    val numberList = listOf(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14)
    printEvenNumbers(numberList)
}

Sample Output:

Explanation:

In the above exercise -

The "printEvenNumbers()" function receives a 'numbers' parameter of type List, representing a list of integers. It iterates through each number in the list and checks if it is even. It uses the modulus operator % to determine if the number divided by 2 has a remainder of 0. If a number is even, it is printed using the "println()" function.

In the "main()" function, a sample number list (numberList) is provided, and "printEvenNumbers()" function is called with this list as an argument. The function then prints only the even numbers in the list.

Go to:

PREV : Print numbers from 1 to n, Return Unit.
NEXT : Check if the number is negative.

Kotlin Editor:

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