Bragging about your rating as a function of solved problems in practice (with solutions available) doesn't seem rational.
HackerRank also used to organize contests where they would have a certain time to tackle a number of new problems (5-10 problems in 1 hour to 1 week, depending on the contest) meaning you have no access to solutions and are competing against other people solving the same problems. They have a rating for performance on those as well.