Calculate with a simple method: 123123*321-321321*123.
用简便方法计算：123123*321-321321*123．
<gadget id="calculator">123_123 * 321</gadget>
<output>39_522_483</output>

<gadget id="calculator">321_321 * 123</gadget>
<output>39_522_483</output>

<gadget id="calculator">39_522_483 - 39_522_483</gadget>
<output>0</output>

<result>0</result>