Introduction

Basic Algorithms

≈ 2 min read

Welcome to Algorithms!

Algorithms appear in almost every program: when you need to find an element, sort data, choose the best option, traverse a structure, or process a large amount of information. Even a familiar operation often hides a specific problem-solving method behind it.

At first, algorithms can look like a collection of separate techniques: two pointers, binary search, stacks, queues, graph traversal, dynamic programming. But behind them are shared ideas — how to model a problem, choose an appropriate data structure, and estimate how fast and memory-efficient a solution will be.

As you move through the course, you will:

learn the fundamental algorithms and data structures;
estimate the time and space complexity of solutions;
learn to recognize common patterns in new problems;
compare different approaches and understand why one fits better than another.

How to get the most out of the course

The routine is simple: understand the idea → trace the algorithm on a small example → solve several exercises → return to the step that is still unclear. With algorithms, it is especially important not just to see finished code, but to be able to explain for yourself why the solution works.

Do not memorize solutions. Each time, try to understand which properties of the problem make a particular approach possible, what the algorithm stores at every step, and why those steps lead to the correct answer.