Essential algorithms and data structures

Second edition

The aim of this book is to provide students and teachers of GCSE, AS & A level Computer Science a comprehensive guide to the algorithms and data structures students need to understand for examinations. Each chapter examines a data structure or algorithm explaining how it works, real-world applications, a step-by-step example, pseudocode, actual code in two languages and a description of the space and time complexity.

We have chosen to provide coded solutions in Python 3 because it is the most popular language taught at GCSE, in Visual Basic Console (2015 onwards) because it is a language that most closely resembles the pseudocode and coded examples students will need to work with in examinations and in C# as it is an industry standard leading language.

This book is appropriate for all English and Welsh Computer Science specifications, check out our up-to-date mapping document for details.

Select the appropriate tile below for additional videos and resources relating to each algorithm.

Download source code in Python, Visual Basic and C#

Help designing and writing algorithms

Data structures

Searching algorithms

Sorting algorithms

Optimisation algorithms

Algorithm efficiency

What extra is in the 200 page book?

Each algorithm / data structure has its own dedicated chapter in the book, which includes:

  1. An overview of the algorithm or data structure
  2. Typical applications and uses
  3. Typical operations with each data structures
  4. The algorithm written in simple structured English
  5. The algorithm written in pseudocode
  6. Full code listing in Python
  7. Source code in Python, Visual Basic and C# are also available to download
  8. Walk-through of the algorithm
  9. Efficiency discussion with reference to Big-O notation

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