Plant trees on both sides of a 100-meter-long road, and plant one tree every 10 meters. How many trees should be planted in total?
在一条长100米公路的两侧栽树，每隔10米栽一棵，一共要栽多少棵．
<gadget id="calculator">100 / 10</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>