public Map<Integer, Double> highFive(Record[] results) {

     HashMap<Integer, PriorityQueue<Integer>> score = new HashMap<>();

    for(Record s : results) {
        if (!score.containsKey(s.id))
       score.put(s.id, new PriorityQueue<Integer>());//Pay Attention!! 有new
       PriorityQueue<Integer> pq = score.get(s.id);
       pq.offer(s.score);
       if (pq.size() > 5)
       pq.poll();
   }

     Map<Integer, Double> res = new HashMap<>();
    for(int sc : score.keySet()) {
        PriorityQueue<Integer> pq = score.get(sc);
        double sum = 0;//Pay Attention!!
        for (int i : pq)
        sum += i;
        res.put(sc, sum/5);
   } 
     return res;
    }