kind of volatile potion, there used to be a whole bottle, but after volatilization on the second day, it becomes the original (1/2) bottle; The (3/4) bottle of the day..., how many days will there be (1/30) bottle of the potion according to this rule?
一种挥发性药水，原来有一整瓶，第二天挥发后变为原来的(1/2)瓶；第三天变为第二天的(2/3)瓶，第四天变为第三天的(3/4)瓶…，请问照此规律第多少天时药水还剩下(1/30)瓶．
<gadget id="calculator">30 / 1</gadget>
<output>30</output>

<result>30</result>