SRM 290 Div2 250

SRM 290 Div2 250

class SpeedTyper
{
public:
  string lettersToPractice(string letters, vector <int> times)
  {
    vector<int> times2;
    int ave = 0;
    for(size_t i = 0; i < times.size(); i++){
      int time = times[i];
      if(i != 0)
        time -= times[i-1];
      ave += time;
      times2.push_back(time);
    }
    ave /= (double)times.size();

    string res;
    for(size_t j = 0; j < times2.size(); j++){
      if(times2[j] > ave){
        res.push_back(letters[j]);
      }
    }
    return res;
  }
};