I've recently started doing CSES problems I found them quite interesting. So far I've completed around first 100 problems (Completed till GraphAlgorithms) I've seen a lot of people asking for help, here are all of my submissions and explanations.
https://github.com/ankitpriyarup/CSES_ProblemSet_Solution
PS: To make it look clean I haven't included my ugly header, in case you want to see it click here
Problemset: https://cses.fi/problemset/list/
Refer this book side by side for theoretical knowledge: https://cses.fi/book/book.pdf