road is 200 meters long. , Plant a tree every 20 meters on both sides of the road, both ends must be planted. How many trees can be planted in total?
一条公路长200米．，在路的两旁每隔20米栽一棵树，两端都要栽．一共可以栽多少棵树？
<gadget id="calculator">200 / 20</gadget>
<output>10</output>

<gadget id="calculator">10 + 1</gadget>
<output>11</output>

<gadget id="calculator">11 * 2</gadget>
<output>22</output>

<result>22</result>