java类和比较

//优先队列
 static Comparator<Integer> cmp = new Comparator<Integer>() {
        public int compare(Integer e1, Integer e2) {
            return e2 - e1;
        }
    };
        //Arrays.sort(a,Collections.reverseOrder());

        Queue<Integer> q = new PriorityQueue<Integer>(cmp);

class Segment implements Comparable<Segment>{
    int data;
    public Segment(int data){
        this.data=data;
    }
    @Override
    public int compareTo(Segment o) {
        return this.data - o.data;
    }
}

 static class Flower implements Comparable<Flower> {
        int a;int b;

        public Flower(int a, int b) {
            this.a = a;
            this.b = b;
        }

        public int compareTo(Flower o) {
            return o.a - a;
        }
    }

flowerList.sort(Comparator.comparing(Flower::getHappiness).reversed());

sort(p, comparingLong(o -> -o.a));