Kotlin Class: Calculate the total cost of a product

Last update on February 05 2025 05:41:35 (UTC/GMT +8 hours)

Write a Kotlin program that creates a class 'Product' with properties for name, price, and quantity. Calculate the total cost of the product with a function.

Pre-Knowledge (Before You Start!)

Before attempting this exercise, you should be familiar with the following concepts:

• Classes in Kotlin: A class is a blueprint for creating objects with specific properties and behaviors.
• Primary Constructor: It is used to initialize the properties of a class when an instance is created.
• Properties: Variables within a class that store values such as name, price, and quantity of a product.
• Functions in Classes: Functions like calculateTotalCost() perform calculations using class properties.
• Object Creation: Creating an instance of a class and calling its functions to compute results.

Hints (Try Before Looking at the Solution!)

Try to solve the problem with these hints:

• Hint 1: Create a class named Product with properties for name, price, and quantity.
• Hint 2: Define a function named calculateTotalCost() inside the class.
• Hint 3: The function should return the product of price and quantity.
• Hint 4: In the main() function, create an instance of the Product class with sample values.
• Hint 5: Call the calculateTotalCost() function on the created object and print the result.

Sample Solution:

Kotlin Code:

class Product(
    val name: String,
    val price: Double,
    val quantity: Int
) {
    fun calculateTotalCost(): Double {
        return price * quantity
    }
}

fun main() {
    val product = Product("Desktop", 2000.0, 4)
    val totalCost = product.calculateTotalCost()
    println("Total Cost: $totalCost")
}

Sample Output:

Total Cost: 8000.0

Explanation:

In the above exercise -

• In this program, we define a class "Product" with three properties: name, price, and quantity, representing the product's name, price, and quantity.
• The class includes a function "calculateTotalCost()" that calculates the total cost of the product by multiplying the price by the quantity.
• In the "main()" function, we create an instance of the Product class named product with the name "Desktop", a price of 2000.0, and a quantity of 4. We then call the calculateTotalCost function on the product object and store the result in the totalCost variable.
• The println function is used to print the total cost calculated.

Kotlin Editor:

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