On one side of a 50-meter-long road, plant a willow tree every 5 meters. If both ends are planted, how many willow trees are needed?
在一段50米长的公路的一侧，每隔5米栽一棵柳树，如果两头都要栽，那么需要多少棵柳树．
<gadget id="calculator">50 / 5</gadget>
<output>10</output>

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

<result>11</result>