哈是受的这个启发：

https://baike.baidu.com/item/%E7%94%9F%E5%91%BD%E7%9A%84%E7%9C%9F%E7%9B%B8%EF%BC%9A%E8%91%9B%E5%90%89%E5%A4%AB%E7%9A%84%E7%AC%AC4%E9%81%93/16338125