Plant sweet-scented osmanthus trees between the two buildings 100 meters apart, and plant one tree every 5 meters. How many trees will be planted in total?
在相距100米的两楼之间栽上桂花树，每隔5米栽一棵，一共要栽多少棵．
<gadget id="calculator">100 / 5</gadget>
<output>20</output>

<gadget id="calculator">20 - 1</gadget>
<output>19</output>

<result>19</result>