#### Overview of this book

Data structures allow organizing data efficiently. They are critical to various problems and their suitable implementation can provide a complete solution that acts like reusable code. In this book, you will learn how to use various data structures while developing in the C# language as well as how to implement some of the most common algorithms used with such data structures. At the beginning, you will get to know arrays, lists, dictionaries, and sets together with real-world examples of your application. Then, you will learn how to create and use stacks and queues. In the following part of the book, the more complex data structures will be introduced, namely trees and graphs, together with some algorithms for searching the shortest path in a graph. We will also discuss how to organize the code in a manageable, consistent, and extendable way. By the end of the book,you will learn how to build components that are easy to understand, debug, and use in different applications.
Title Page
Packt Upsell
Contributors
Preface
Free Chapter
Getting Started
Arrays and Lists
Stacks and Queues
Dictionaries and Sets
Variants of Trees
Exploring Graphs
Summary
Other Books You May Enjoy
Index

## Sorting algorithms

There are many algorithms that perform various operations on arrays. However, one of the most common tasks is sorting an array to arrange its elements in the correct order, either ascending or descending. The topic of sorting algorithms involves many approaches, including selection sort, insertion sort, bubble sort, and quicksort, which will be explained in detail in this part of the chapter.

### Selection sort

Let's start with the selection sort, which is one of the simplest sorting algorithms. The algorithm divides the array into two parts, namely sorted and unsorted. In the following iterations, the algorithm finds the smallest element in the unsorted part and exchanges it with the first element in the unsorted part. It sounds very simple, doesn't it?

To better understand the algorithm, let's take a look at the following iterations for an array with nine elements (-11, 12, -42, 0, 1, 90, 68, 6, -9), as shown in the following diagram:

To simplify the analysis, the bold line...