Iterating collections with forEach in Kotlin - Mini Project: Build & Apply

Iterating collections with forEach

📖 Scenario: You are helping a small bookstore manage its inventory. You have a list of book titles and want to print each title to check the stock.

🎯 Goal: Learn how to use the forEach function in Kotlin to go through each item in a list and print it.

📋 What You'll Learn

Create a list of book titles with exact values

Create a variable to count the number of books

Use forEach to print each book title

Print the total number of books after listing them

💡 Why This Matters

🌍 Real World

Bookstores and libraries often need to list and count their inventory. Using <code>forEach</code> helps to process each item easily.

💼 Career

Knowing how to iterate collections is essential for many programming jobs, especially when working with data lists or user inputs.

1

Create a list of book titles

Create a list called books with these exact titles: "The Hobbit", "1984", "Pride and Prejudice", "To Kill a Mockingbird"

Kotlin

# Create the list of books below
# Your code here

Need a hint?

Use listOf to create a list with the given book titles.

2

Create a variable to count books

Create a variable called bookCount and set it to the size of the books list

Kotlin

val books = listOf("The Hobbit", "1984", "Pride and Prejudice", "To Kill a Mockingbird")
# Create the variable bookCount below
# Your code here

Need a hint?

Use the size property of the list to get the number of books.

3

Use forEach to print each book title

Use books.forEach with a lambda that takes a parameter called book and prints it

Kotlin

val books = listOf("The Hobbit", "1984", "Pride and Prejudice", "To Kill a Mockingbird")
val bookCount = books.size
# Use forEach to print each book title below
# Your code here

Need a hint?

Use forEach with a lambda that prints each book.

4

Print the total number of books

Write a println statement that prints exactly: Total books: 4 using the bookCount variable inside an f-string

Kotlin

val books = listOf("The Hobbit", "1984", "Pride and Prejudice", "To Kill a Mockingbird")
val bookCount = books.size
books.forEach { book ->
    println(book)
}
# Print the total number of books below
# Your code here

Need a hint?

Use println("Total books: $bookCount") to show the total count.