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

Bubble sort


The idea behind a bubble sort algorithm is very simple. Given an unordered list, we compare adjacent elements in the list, each time, putting in the right order of magnitude, only two elements. The algorithm hinges on a swap procedure.

Take a list with only two elements:

To sort this list, simply swap them into the right position with 2 occupying index 0 and 5 occupying index 1. To effectively swap these elements, we need to have a temporary storage area:

Implementation of the bubble sort algorithm starts with the swap method, illustrated in the preceding image. First, element 5 will be copied to a temporary location, temp. Then element 2 will be moved to index 0. Finally, 5 will be moved from temp to index 1. At the end of it all, the elements will have been swapped. The list will now contain the element: [2, 5]. The following code will swap the elements of unordered_list[j] with unordered_list[j+1] if they are not in the right order:

    temp = unordered_list[j] 
    unordered_list...