1989*1999-1988*2000.
1989*1999-1988*2000．
<gadget id="calculator">1_989 * 1_999</gadget>
<output>3_976_011</output>

<gadget id="calculator">1_988 * 2_000</gadget>
<output>3_976_000</output>

<gadget id="calculator">3_976_011 - 3_976_000</gadget>
<output>11</output>

<result>11</result>