struct Comparator
{
  bool operator()(const process &lhs, const process &rhs) const
  {
    if(lhs.get_Priority() == rhs.get_Priority())
        return (lhs.get_arrivalTime() > rhs.get_arrivalTime());
    else
        return (lhs.get_Priority() > rhs.get_Priority());
  }
};

priority_queue<process, deque<process>, Comparator> ReadyQueue;