The runway of the school playground is 300 meters in one lap. After Li Ming runs 3 laps, the number of meters he runs is 1 kilometer.
学校操场的跑道一圈是300米，李明跑了3圈后再跑多少米就是1千米了．
<gadget id="calculator">1 * 1_000</gadget>
<output>1_000</output>

<gadget id="calculator">300 * 3</gadget>
<output>900</output>

<gadget id="calculator">1_000 - 900</gadget>
<output>100</output>

<result>100</result>