Destructuring in collection iteration in Kotlin - Mini Project: Build & Apply

Destructuring in Collection Iteration

📖 Scenario: You are managing a small library database. Each book has a title and an author. You want to organize this data and then use Kotlin's destructuring feature to easily access each book's details.

🎯 Goal: Build a Kotlin program that stores a collection of books as pairs of title and author, then uses destructuring in a for loop to iterate over the collection and access each book's title and author separately.

📋 What You'll Learn

Create a list of pairs called books with exact entries: ("1984", "George Orwell"), ("Brave New World", "Aldous Huxley"), ("Fahrenheit 451", "Ray Bradbury")

Create a variable called count and set it to 0

Use a for loop with destructuring syntax for ((title, author) in books) to iterate over books

Inside the loop, increment count by 1

After the loop, create a variable called totalBooks and assign it the value of count

💡 Why This Matters

🌍 Real World

Destructuring helps you easily access parts of data structures like pairs or triples, which is common when working with database records or API responses.

💼 Career

Many Kotlin jobs require handling collections of data efficiently. Destructuring makes your code cleaner and easier to read when processing such data.

1

Create the books list

Create a list called books with these exact pairs: ("1984", "George Orwell"), ("Brave New World", "Aldous Huxley"), and ("Fahrenheit 451", "Ray Bradbury")

Kotlin

# Create the books list with exact pairs
# Your code here

Need a hint?

Use listOf and the to keyword to create pairs.

2

Add a counter variable

Create a variable called count and set it to 0

Kotlin

val books = listOf(
    "1984" to "George Orwell",
    "Brave New World" to "Aldous Huxley",
    "Fahrenheit 451" to "Ray Bradbury"
)

# Create a variable called count and set it to 0
# Your code here

Need a hint?

Use var to create a variable that can change.

3

Iterate with destructuring

Use a for loop with destructuring syntax for ((title, author) in books) to iterate over books. Inside the loop, increment count by 1

Kotlin

val books = listOf(
    "1984" to "George Orwell",
    "Brave New World" to "Aldous Huxley",
    "Fahrenheit 451" to "Ray Bradbury"
)

var count = 0

# Use a for loop with destructuring to iterate over books
# Inside the loop, increment count by 1
# Your code here

Need a hint?

Use parentheses to destructure each pair into title and author.

4

Assign totalBooks variable

After the loop, create a variable called totalBooks and assign it the value of count

Kotlin

val books = listOf(
    "1984" to "George Orwell",
    "Brave New World" to "Aldous Huxley",
    "Fahrenheit 451" to "Ray Bradbury"
)

var count = 0

for ((title, author) in books) {
    count += 1
}

# Create a variable totalBooks and assign it count
# Your code here

Need a hint?

Use val to create a read-only variable.