Process a batch of coats, 1000 pieces have been processed, accounting for (1/5) of the total number, how many pieces are left unprocessed?
加工一批上衣，已加工1000件，占总数的(1/5)，还有多少件没加工？
<gadget id="calculator">5_000 - 1_000</gadget>
<output>4_000</output>

<result>4_000</result>