This guide was designed to help those studying for competitive programming, mostly beginner and intermediate competitors who don't know where to study. Here you can find links for good tutorials for some of the most important topics, covering the basic concepts and some advanced ones. They are divided by categories, and every topic has a difficulty level inside its category. Furthermore, we also list some great websites where you can practice and test your skills. Check it out clicking here.
Feel free to contribute by adding more tutorials and topics via pull request!