My summer project about Competitive Programming includes a variety of problems from Hackerrank and Algo.is (Kattis). There are also additional problems from the North American Qualifier/Regional Competition and LeetCode that I am still updating...
Algo.is Competitive Programming Course: https://algo.is/
For preferences, here are my profile on Hackerrank and Kattis;
HACKERRANK: https://www.hackerrank.com/quan_chau (~300 problems)
KATTIS: https://open.kattis.com/users/quan-chau (~120 problems)
List of problems of each topic will be included in the subfolders.
*Note: Many solutions I posted on GitHub are not optimal yet (may not pass some test cases) so be careful if you want to use them.