If a tree is planted every 2 meters on both sides of a 50-meter-long road, and both ends are planted, how many trees are needed in total?
在一条长50米的马路两边每隔2米栽一棵树，两端都栽，共要树多少棵．
<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<gadget id="calculator">25 + 1</gadget>
<output>26</output>

<gadget id="calculator">26 * 2</gadget>
<output>52</output>

<result>52</result>