It took Honghong 12 seconds to walk from the first floor to the third floor, how many seconds will it take to walk to the fourth floor?
红红从一楼走到三楼用了12秒，走到四楼共要用几秒？
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">6 * 3</gadget>
<output>18</output>

<result>18</result>