Plant trees on both sides of a 400-meter-long path (both ends are planted), and plant one tree every 4 meters. How many saplings are needed in total?
在一条长400米的小路两旁栽树(两端都栽)，每隔4米栽一棵，一共需多少棵树苗？
<gadget id="calculator">400 / 4</gadget>
<output>100</output>

<gadget id="calculator">100 + 1</gadget>
<output>101</output>

<gadget id="calculator">101 * 2</gadget>
<output>202</output>

<result>202</result>