Algorithms and Data Structures in C# (.NET)

The book "Algorithms and Data Structures in C# (.NET)" is a modern practical guide that helps developers master fundamental computer science concepts through the lens of the .NET platform and the C# language. Unlike abstract textbooks, this book focuses on real-world problems every programmer faces: from optimizing search in large arrays to building efficient message queues.

What is this book about?

The book covers a full range of topics necessary for confident mastery of data structures and algorithms:

• Basic structures: arrays, lists, stack, queue, dictionaries — their internal implementation in .NET and when to choose which.
• Advanced structures: trees (binary, AVL, red-black), graphs, hash tables, heaps, and their implementation in C#.
• Sorting and search algorithms: from bubble sort to quicksort, binary search, BFS/DFS on graphs.
• Dynamic programming and greedy algorithms: analysis of classic problems (knapsack, shortest path, edit distance).
• Memory and performance: Big O notation, Span, Memory, allocations, and garbage collection.
• Modern .NET features: LINQ, parallel algorithms (Task, Parallel), asynchronous queues.

Who is this book for?

The book is intended for junior and middle C# developers who want to move from writing "working" code to creating efficient and scalable solutions. It will also be useful for technical students and developers preparing for technical interviews — each chapter includes an analysis of typical FAANG interview problems.

What will the reader learn?

• How to choose the right data structure for a specific task without overpaying for performance.
• How to write algorithms that run fast and don't "eat up" memory (especially in high-load systems).
• How to use built-in .NET capabilities (collections, LINQ, Parallel) to solve algorithmic problems.
• How to prepare for interviews: the book contains over 50 practical problems with step-by-step solution analysis in C#.
• How to profile and optimize existing code using BenchmarkDotNet and memory analyzers.

Each chapter is built on the principle of "theory → code example → problem for independent solution." All examples are written in current versions of C# (.NET 8/9) and are ready to run in your IDE. The book will become a desktop reference for those who want to write code they can be proud of.

Note: the book does not require deep mathematical knowledge — all complex concepts are explained through practice and visualization. A confident grasp of C# basics and a desire to understand how algorithms work "under the hood" is sufficient.