Frequently asked questions
Is AlgoRung free?
Yes. Every problem, solution and animated walkthrough is free to read and watch, with no account needed.
Do I need an account?
Only to keep a revision log. Reading problems, solutions and walkthroughs works without signing in. Your log records when you solved each problem, your time, attempts, mistakes and notes, and schedules your revisions.
Which programming language are the solutions in?
Java. Each problem has one or more approaches, usually from brute force to optimal, with the time and space complexity of each.
How many problems are there?
231 problems across 14 topics, from arrays and strings to graphs and dynamic programming. Each topic is grouped into patterns, so similar problems sit together.
What are the animated walkthroughs?
Narrated animations, about eight to ten minutes each, that teach the concept, trace an example step by step and explain the code line by line. 231 problems have one, and they are also on YouTube.
How does the revision schedule work?
After your first solve, you revise the problem twice: a few days later, then two days after that. Each time you solve it from a blank editor and log your time, attempts and mistakes. The goal is under ten minutes in one attempt.
In what order should I practise?
Follow the DSA sheet from top to bottom: each topic builds on the ones before it. Inside a topic, work through one pattern at a time.
Where do the problems come from?
They are well-known interview questions, most of them hosted on LeetCode or GeeksforGeeks. AlgoRung writes its own explanation of each and links to the original so you can submit your code there. AlgoRung is not affiliated with either site.
Is there Hindi narration?
Hindi narration with English captions is being added problem by problem. Where it exists, a language switch appears on the walkthrough.
I found a mistake. How do I report it?
Email hello@algorung.com with the problem name and what looks wrong.
Still have a question? Write to hello@algorung.com.