Codeforces is really a good place for programmers. In the past several months I have made big progress.

Next week I'm going to participate in provincial selection contest. All problems have at least the same difficulty as div1 problem C. Half a year a later that just make no sense to me but now I can come up with some solutions to pass some subtasks.

Round #238 will be my last CF contest before the selection. I hope I will do better...Anyway thanks Codeforces very much.

So my next target is becoming grandmaster before the end of this year, hope I can achieve it!