There are 216 steps in the building. If there are 18 steps between every two floors, how many floors does the building have?
大楼共有216级台阶，如果每两层楼之间都是18级台阶，大楼共有多少层？
<gadget id="calculator">216 / 18</gadget>
<output>12</output>

<gadget id="calculator">12 + 1</gadget>
<output>13</output>

<result>13</result>