A swimming pool is 50 meters long, how many round trips do you need to swim 1 kilometer?
游泳池长50米，要游1千米，需要游多少个来回．
<gadget id="calculator">1_000 / 50 / 2</gadget>
<output>10</output>

<gadget id="calculator">1 * 10</gadget>
<output>10</output>

<result>10</result>