Book Image

PHP 7 Data Structures and Algorithms

By : Rahman
5 (1)
Book Image

PHP 7 Data Structures and Algorithms

5 (1)
By: Rahman

Overview of this book

PHP has always been the the go-to language for web based application development, but there are materials and resources you can refer to to see how it works. Data structures and algorithms help you to code and execute them effectively, cutting down on processing time significantly. If you want to explore data structures and algorithms in a practical way with real-life projects, then this book is for you. The book begins by introducing you to data structures and algorithms and how to solve a problem from beginning to end using them. Once you are well aware of the basics, it covers the core aspects like arrays, listed lists, stacks and queues. It will take you through several methods of finding efficient algorithms and show you which ones you should implement in each scenario. In addition to this, you will explore the possibilities of functional data structures using PHP and go through advanced algorithms and graphs as well as dynamic programming. By the end, you will be confident enough to tackle both basic and advanced data structures, understand how they work, and know when to use them in your day-to-day work
Table of Contents (14 chapters)

Understanding complexity of stack operations

Here is the time complexity of different stack operations. For the worst case, the time complexities for stack operations are as follows:

Operation

Time Complexity

pop

O(1)

push

O(1)

top

O(1)

isEmpty

O(1)

Since the stack operates at one end that remembers the top of the stack all the time, if we want to search for an item in the stack, it means we have to search through the whole list. It is the same for accessing a particular item in the stack. Although it is not good practice to use stack for these sorts of operations, if we want to do so, we have to remember that the time complexity is based on more than general stack operations.

Operation

Time Complexity

Access

O(n)

Search

O(n)

The space complexity for stack is always O(n).

So far, we have seen how to implement stack using...