A number consists of 7 thousands, 3 thousands and 1 hundred.
一个数由7个万、3个千和1个百组成．
<gadget id="calculator">7 * 10_000</gadget>
<output>70_000</output>

<gadget id="calculator">3 * 1_000</gadget>
<output>3_000</output>

<gadget id="calculator">70_000 + 3_000 + 100</gadget>
<output>73_100</output>

<result>73_100</result>