The school should plant trees on both sides of the 60-meter-long path, and plant a tree every 2 meters (both at the end and the end), how many trees can be planted in total.
学校要在长60米的小路两边植树，每隔2米植一棵树(首尾都植)，一共可以植多少棵．
<gadget id="calculator">60 / 2</gadget>
<output>30</output>

<gadget id="calculator">30 + 1</gadget>
<output>31</output>

<gadget id="calculator">31 * 2</gadget>
<output>62</output>

<result>62</result>