Range operator (..) and in operator in Kotlin - Mini Project: Build & Apply

Using Range Operator (..) and in Operator in Kotlin

📖 Scenario: You are organizing a small event and want to check if guests' ages fall within a certain age range for eligibility.

🎯 Goal: Build a Kotlin program that uses the range operator .. to create an age range and the in operator to check if a guest's age is within that range.

📋 What You'll Learn

Create an integer variable called guestAge with the value 25

Create a range called eligibleAgeRange from 18 to 30 using the .. operator

Use an if statement with the in operator to check if guestAge is in eligibleAgeRange

Print "Guest is eligible" if the age is in range, otherwise print "Guest is not eligible"

💡 Why This Matters

🌍 Real World

Checking if a person's age or a number falls within a valid range is common in forms, games, and eligibility checks.

💼 Career

Understanding ranges and membership tests is useful for data validation, filtering, and controlling program logic in many software development roles.

1

Create the guest age variable

Create an integer variable called guestAge and set it to 25.

Kotlin

// Create an integer variable called guestAge and set it to 25
// Your code here

Need a hint?

Use val guestAge = 25 to create the variable.

2

Create the eligible age range

Create a range called eligibleAgeRange from 18 to 30 using the .. operator.

Kotlin

val guestAge = 25
// Create a range called eligibleAgeRange from 18 to 30 using .. operator
// Your code here

Need a hint?

Use val eligibleAgeRange = 18..30 to create the range.

3

Check if guest age is in the eligible range

Use an if statement with the in operator to check if guestAge is in eligibleAgeRange. Inside the if, write println("Guest is eligible"). In the else block, write println("Guest is not eligible").

Kotlin

val guestAge = 25
val eligibleAgeRange = 18..30
// Use if with in operator to check if guestAge is in eligibleAgeRange
// Print "Guest is eligible" if true, else print "Guest is not eligible"
// Your code here

Need a hint?

Use if (guestAge in eligibleAgeRange) to check the range.

4

Print the eligibility result

Run the program to print the eligibility message based on the guest's age.

Kotlin

val guestAge = 25
val eligibleAgeRange = 18..30
if (guestAge in eligibleAgeRange) {
    println("Guest is eligible")
} else {
    println("Guest is not eligible")
}
// Run the program to see the output

Need a hint?

Check the console output for the eligibility message.