Chapter 1, Why Bother? – Basic, introduces the point of studying algorithms and data structures with examples. In doing so, it introduces you to the concept of asymptotic complexity, big O notation, and other notations.

Chapter 2, Cogs and Pulleys – Building Blocks, introduces you to array and the different kinds of linked lists, and their advantages and disadvantages. These data structures will be used in later chapters for implementing abstract data structures.

Chapter 3, Protocols – Abstract Data Types, introduces you to the concept of abstract data types and introduces stacks, queues, and double-ended queues. It also covers different implementations using the data structures described in the previous chapter.

Chapter 4, Detour – Functional Programming, introduces you to the functional programming ideas appropriate for a Java programmer. The chapter also introduces the lambda feature of Java, available from Java 8, and helps readers get used to the functional way of implementing algorithms. This chapter also introduces you to the concept of monads.

Chapter 5, Efficient Searching – Binary Search and Sorting, introduces efficient searching using binary searches on a sorted list. It then goes on to describe basic algorithms used to obtain a sorted array so that binary searching can be done.

Chapter 6, Efficient Sorting – Quicksort and Mergesort, introduces the two most popular and efficient sorting algorithms. The chapter also provides an analysis of why this is as optimal as a comparison-based sorting algorithm can ever be.

Chapter 7, Concepts of Tree, introduces the concept of a tree. It especially introduces binary trees, and also covers different traversals of the tree: breadth-first and depth-first, and pre-order, post-order, and in-order traversal of binary tree.

Chapter 8, More About Search – Search Trees and Hash Tables, covers search using balanced binary search trees, namely AVL, and red-black trees and hash-tables.

Chapter 9, Advanced General Purpose Data Structures, introduces priority queues and their implementation with a heap and a binomial forest. At the end, the chapter introduces sorting with a priority queue.

Chapter 10, Concepts of Graph, introduces the concepts of directed and undirected graphs. Then, it discusses the representation of a graph in memory. Depth-first and breadth-first traversals are covered, the concept of a minimum-spanning tree is introduced, and cycle detection is discussed.

Chapter 11, Reactive Programming, introduces the reader to the concept of reactive programming in Java. This includes the implementation of an observable pattern-based reactive programming framework and a functional API on top of it. Examples are shown to demonstrate the performance gain and ease of use of the reactive framework, compared with a traditional imperative style.

To run the examples in this book, you need a computer with any modern popular operating system, such as some version of Windows, Linux, or Macintosh. You need to install Java 9 in your computer so that javac can be invoked from the command prompt.

This book is for Java developers who want to learn about data structures and algorithms. A basic knowledge of Java is assumed.

In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "We can include other contexts through the use of the include directive."

A block of code is set as follows:

public static void printAllElements(int[] anIntArray){ 
        for(int i=0;i<anIntArray.length;i++){ 
            System.out.println(anIntArray[i]); 
        } 
    }

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

public static void printAllElements(int[] anIntArray){ 
        for(int i=0;i<anIntArray.length;i++){ 
            System.out.println(anIntArray[i]); 
        } 
    }

Any command-line input or output is written as follows:

# cp /usr/src/asterisk-addons/configs/cdr_mysql.conf.sample
     /etc/asterisk/cdr_mysql.conf

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "Clicking the Next button moves you to the next screen."

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To send us general feedback, simply e-mail <[email protected]>, and mention the book's title in the subject of your message.

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