Unable to think the answer

I am not able to think of the answers, and also not able to solve the problems given in the challenges section on my own and without looking at the solutions.
could you please suggest what I should do?
Should I remember the solutions to these questions?

@discobot Try to approach the question using the Smaller problem and bigger problem concepts. Don’t remember the solution instead use these questions to see how recursion is applied(By using the solutions) after using solutions try to ask these questions on your own again with the recursion tree.

Hi! To find out what I can do, say @discobot display help.