#### Overview of this book

Data structures and algorithms are more than just theoretical concepts. They help you become familiar with computational methods for solving problems and writing logical code. Equipped with this knowledge, you can write efficient programs that run faster and use less memory. Hands-On Data Structures and Algorithms with Kotlin book starts with the basics of algorithms and data structures, helping you get to grips with the fundamentals and measure complexity. You'll then move on to exploring the basics of functional programming while getting used to thinking recursively. Packed with plenty of examples along the way, this book will help you grasp each concept easily. In addition to this, you'll get a clear understanding of how the data structures in Kotlin's collection framework work internally. By the end of this book, you will be able to apply the theory of data structures and algorithms to work out real-world problems.
Preface
Free Chapter
Section 1: Getting Started with Data Structures
A Walk Through - Data Structures and Algorithms
Arrays - First Step to Grouping Data
Section 2: Efficient Grouping of Data with Various Data Structures
Understanding Stacks and Queues
Maps - Working with Key-Value Pairs
Section 3: Algorithms and Efficiency
Deep-Dive into Searching Algorithms
Understanding Sorting Algorithms
Section 4: Modern and Advanced Data Structures
Collections and Data Operations in Kotlin
Introduction to Functional Programming
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Assessments

# Implementing HashMap

So far, we have seen how a Map works internally. In this section, we'll try to create a simple Map and understand how the preceding topics can be implemented. Instead of looking at the whole implementation in a single place, we'll try to understand it chunk by chunk. For the full implementation, please visit this book's GitHub repository.

# A template of the HashMap class

Since the implementation is based on hashing, we named it HashMap. There is nothing strict about the naming though. The following is the template code for our HashMap:

`class HashMap<K, V> {    private val minCapacity = 1 shl 4    private val maxCapacity = 1 shl 30    private var table: Array<Node<K, V>?&gt...`