You can see that i'm a Newbie now,but i think i have ability at least Pupil because i have sloved some problems of rating 1300.I think if i attend some more contests,i can gain rating to at least 1250.

It's natural and now my problem is What should i do to gain my rating to 1700 in 6 months?

By the way,because of my learning tasks in school,i don't have much time to practice competitive programming every day,so i don't want to spend too much time(for example, 2 hours a day on weekdays).