There is a big wall clock on the clock tower, which strikes once every hour, and how many times at what time, for example, 3 times at 3 o'clock, and 6 seconds to finish. Then, knock 9 times at 9 o'clock, how many seconds to finish knocking.
钟楼上有一个大挂钟，每小时敲1次，几点钟敲几下，如3点时敲3下，6秒敲完．那么，9点时敲9下，多少秒敲完．
<gadget id="calculator">9 - 1</gadget>
<output>8</output>

<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">8 * 3</gadget>
<output>24</output>

<result>24</result>