Hey everyone! Just wanted to ask some questions. I'm currently solving problems from the a2oj [1300, 1399] ladder which contains problems from rating ranges 1100-1500. I'm kind of starting to feel confident with 1500 rated problems, but when I should switch to 1600 and 1700s. Should I switch when I solve 1500s in like 20-30 minutes?

• Also, Is it possible to succeed in competitive programming by only solving cf problems or are there websites that are more suitable for beginners? And if you can, please share your ways of/tips on cp training. I'm really sure that I will not be the only one who would benefit from them.

Thanks in advance!