This is my first long challenge. I read that long challenges are especially useful for beginners to learn a new concept and apply it to problems. Quoting the homepage of June Long Challenge,
What’s in it for you?
The idea behind these programming contests is that we want you to learn while competing. Also we believe that it is alright to refer to tutorials, books and other materials, learn a concept and then apply the same to solve a problem during a contest.
But I noticed that the challenges do not have topic tags. I got three problems from June long challenge. If I want to solve the others, how do I know whether I know the topic required for solving the problem (and if I do not know the topic, what is the topic to be learnt). I personally feel that if a problem involves a new topic and I do not know it, it will be a waste of time trying different unfruitful approaches to the problem.