Book Image

PHP 7 Programming Cookbook

By : Doug Bierer
Book Image

PHP 7 Programming Cookbook

By: Doug Bierer

Overview of this book

PHP 7 comes with a myriad of new features and great tools to optimize your code and make your code perform faster than in previous versions. Most importantly, it allows you to maintain high traffic on your websites with low-cost hardware and servers through a multithreading web server. This book demonstrates intermediate to advanced PHP techniques with a focus on PHP 7. Each recipe is designed to solve practical, real-world problems faced by PHP developers like yourself every day. We also cover new ways of writing PHP code made possible only in version 7. In addition, we discuss backward-compatibility breaks and give you plenty of guidance on when and where PHP 5 code needs to be changed to produce the correct results when running under PHP 7. This book also incorporates the latest PHP 7.x features. By the end of the book, you will be equipped with the tools and skills required to deliver efficient applications for your websites and enterprises.
Table of Contents (22 chapters)
PHP 7 Programming Cookbook
Credits
Foreword
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Building a binary search class


Conventional searches often proceed through the list of items in a sequential manner. This means that the maximum possible number of items to be searched could be the same as the length of the list! This is not very efficient. If you need to expedite a search, consider implementing a binary search.

The technique is quite simple: you find the midpoint in the list, and determine whether the search item is less than, equal to, or greater than the midpoint item. If less, you set the upper limit to the midpoint, and search only the first half of the list. If greater, set the lower limit to the midpoint, and search only the last half of the list. You would then proceed to divide the list into 1/4, 1/8, 1/16, and so on, until the search item is found (or not).

Note

It's important to note that although the maximum number of comparisons is considerably smaller than a sequential search (log n + 1 where n is the number of elements in the list, and log is the binary logarithm...