There are 8 willow trees planted on the side of a road, and the distance between every two willow trees is 5 meters. How long is the road?
在一条公路的一旁种了8棵柳树，每两棵柳树之间相距5米，这条公路有多长？
<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">7 * 5</gadget>
<output>35</output>

<result>35</result>