I mean prerequisites.
check this awesome link for u.
You need to know discrete maths, and DSA.
But as you see, seeing the editorial and learning the algorithms is itself a process of learning. Since you are in the learning stage , try the problem , if you don’t get learn the problem and do it again.
Start from easy-medium and go to difficult level.
Take part in contest actively.See the editorial and try to improve your coding style.
And keep practicing , when you learn a new concept of algorithms , try doing problem of similar type and get a good hold of it.
After some time you will be able to do difficult problems , without seeing the editorial.
You should search the forum once, many great coders have answered this question pretty well.
Also, please specify a few things like your experience with coding, what you know and what you don’t, what topics you are well equipped with or any other stuff which would help us know your current condition. We can provide apt answers to you after that :).
Really? Do you have no access to google? please at least give time to search your query first at google. There are plenty of answers available.
@bansal1232 Ha ha ha