Hi there CF community , I am currently able to do Div2 A & B and want to also be able to do C problem for that i saw that everyone was recommending A20J Ladders , while i appreciate the effort someone took to make that i realized that those are like 5-6 years OLD ! ! Which makes me wonder are they still relevant and moreover Helpful as per today's and future standards ? ?

I really urge senior cp-programmers to please advice me on how i should practice as of 2020 ? should i keep following A20J or can you give me some other curated list or any other method ?

Please help.