Book Image

Python Data Structures and Algorithms

By : Benjamin Baka
Book Image

Python Data Structures and Algorithms

By: Benjamin Baka

Overview of this book

Data structures allow you to organize data in a particular way efficiently. They are critical to any problem, provide a complete solution, and act like reusable code. In this book, you will learn the essential Python data structures and the most common algorithms. With this easy-to-read book, you will be able to understand the power of linked lists, double linked lists, and circular linked lists. You will be able to create complex data structures such as graphs, stacks and queues. We will explore the application of binary searches and binary search trees. You will learn the common techniques and structures used in tasks such as preprocessing, modeling, and transforming data. We will also discuss how to organize your code in a manageable, consistent, and extendable way. The book will explore in detail sorting algorithms such as bubble sort, selection sort, insertion sort, and merge sort. By the end of the book, you will learn how to build components that are easy to understand, debug, and use in different applications.
Table of Contents (20 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
5
Stacks and Queues
7
Hashing and Symbol Tables

Weighted graphs


A weighted graph adds a bit of extra information to the edges. This can be a numerical value that indicates something. Let's say, for example, that the following graph indicates different ways to get from point A to point D. You can either go straight from A to D, or choose to pass through B and C. Associated with each edge is the amount of time in minutes the journey to the next node will take:

Perhaps the journey AD would require you to ride a bike (or walk). B and C might represent bus stops. At B you would have to change to a different bus. Finally, CD may be a short walk to reach D.

In this example, AD and ABCD represent two different paths. A path is simply a sequence of edges that you pass through between two nodes. Following these paths, you see that the total journey AD takes 40 minutes, whereas the journey ABCD takes 25 minutes. If your only concern is time, you would be better off traveling along ABCD, even with the added inconvenience of changing buses.

The fact...