This is a very comprehensive 94-part course on competitive programming. It gets you from knowing basic programming to being a yellow-red rated coder on Codeforces / CodeChef / TopCoder / etc.

The primary objectives of this course are to learn about 30 different algorithms and data structures. The algorithm tutori...

This 28-part course consists of tutorials on data structures and algorithms. It alternates between tutorials and implementation, and you get to implement every algorithm. You can think of this course as a "Free Online Nano Book".

This course teaches algorithms and data structures f...

This is a 100+ part playbook that takes you from basic C++ programming to a Gold medal at IOI. It has tutorials on 30+ algorithms and data structures, and 75+ problems based on those topics, sorted by increasing difficulty.

This playlist covers the required amount of C++ / Java / Python knowledge you need for programming contests such as Olympiad in Informatics, CodeChef, Codeforces, etc.

Expected time to completion: 5-10 sessions.

The programming language topics covered are input-ou...

Since the last few days, the IARCS website has been down and giving fatal error for C++ submissions. For the time being, I request people to skip the IARCS problems. I've contacted the maintainers, and they said they'll fix it soon. You can still continue making submissions for non-C++ languages.

If you know alternate websites with similar problems, you can help by posting a link to the problem as a reply to the discussion. Tag it with alternate websites, so that it is easy to find.

You can follow this discussion by clicking the thumbs up button. I'll post a reply when they fix it and you'll get a notification.