Kotlin Function: Calculate area of rectangle with default Values

Last update on August 27 2025 12:41:53 (UTC/GMT +8 hours)

Write a Kotlin function that calculates and returns the area of a rectangle. It should take 'length' and 'width' as arguments, with default values of 0.0.

Pre-Knowledge (Before you start!)

Basic Kotlin Syntax.
Kotlin Functions.
Default Arguments.
Arithmetic Operations.
Printing Output.

Hints (Try before looking at the solution!)

Define the Function.
Calculate the Area.
Call the Function.
Display the Output.
Test with Different Values.
Common Errors to Avoid:
- Forgetting default values.
- Misplacing multiplication logic.
- Not validating negative inputs.

Sample Solution:

Kotlin Code:

fun calculateArea(length: Double = 0.0, width: Double = 0.0): Double {
    return length * width
}

fun main() {
    val area = calculateArea(7.0, 3.0)
    println("The area of the rectangle is: $area")
}

Sample Output:

The area of the rectangle is: 21.0

Explanation:

In the above exercise -

The "calculateArea()" function takes two parameters: length and width, both of type Double. These parameters have default values of 0.0, which means they can be omitted when calling the function.
Inside the function, it calculates the rectangle area by multiplying the length and width values. The result is then returned as a Double value.
In the "main()" function, we call the "calculateArea()" function with a length of 7.0 and width of 3.0. The returned area value is stored in the area variable, and then printed using println() function.

Go to:

PREV : Print message without return.
NEXT : Check number divisibility by 7.

Kotlin Editor:

Improve this sample solution and post your code through Disqus