Hi all, this is my first post so please be polite :-) It's been around 3 weeks I'm actively solving problems. I'm able to solve around 5 problems a day (Level C and D). Most of the time I'm able to come up with rough idea/brute force to solve the question then nearly every time I miss some edge cases then again come back, make changes and submit, then get AC. I was wondering how I could possibly get better, since I'm able to only solve A and B problems in contest.

And also, I was wondering how many problems are others able to solve in one day? How do I improve the rate of solving problems?