After a person takes the elevator up from the 2nd floor to the 18th floor, he finds that he went to the wrong floor and went down 3 floors. What floor is the person on now?
某人乘电梯从地下2层上升18层后，发现自己走错了楼层，又下降了3层，此人现在在第多少层．
<gadget id="calculator">18 - 1</gadget>
<output>17</output>

<gadget id="calculator">17 - 3</gadget>
<output>14</output>

<result>14</result>