Just use AI ===============, I'm kidding, if you want to go from 0 to 1400 in 1 month, review the questions from previous contests every day, for example, if you want to start from 0, try to work on the questions A, B, C, D in div 4 yourself. If your rating reaches 800, go to div 3, work on questions A and B, and continue like that. If the questions in div 3, A, B, C, are easy for you, go to div 2, don't use AI. It won't help you if you use AI. If you don't understand the question, look at its explanations on YouTube or elsewhere. This is how I got to 1400 in 1 month.