#### 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

# Vectors (dynamic arrays)

One of the most common problems we face while working with arrays is that we need to know the size of the array during its initialization. It isn't possible to know the size of the array up-front during its initialization. Imagine a case where you're building a social networking project, and you're trying to fetch all of the friends of a particular user from the server and display these in the UI. The number of friends that a user has can't be known unless we get the response from the server. These kinds of situations can be handled using vectors.

A vector is nothing but a data structure backed by an array, which can grow in size when required. Let's try to build a simple implementation of the Vector class to understand it more:

`class Vector <E> {    private val minCapacityIncrement = 12    var elements: Array <Any?&gt...`