When Zhao Gang was doing a calculation problem, he wrongly wrote 85*(□+4) as 85*□+4, how much difference did he get from the correct result?
赵刚在做一道计算题时，把85*(□+4)错写成了85*□+4，这样他得到的结果与正确结果相差多少？
<gadget id="calculator">85 * 4</gadget>
<output>340</output>

<gadget id="calculator">340 - 4</gadget>
<output>336</output>

<result>336</result>