rectangular flower bed is 16 meters long and 3 meters wide. There is a railing around it, how many meters long is the railing?
一个长方形花坛，长16米，宽3米．在它的四周围一圈栏杆，栏杆长多少米．
<gadget id="calculator">16 + 3</gadget>
<output>19</output>

<gadget id="calculator">19 * 2</gadget>
<output>38</output>

<result>38</result>