99999*99999+99999*99999+99999=how many.
99999*99999+99999*99999+99999=多少．
<gadget id="calculator">99_999 * 99_999</gadget>
<output>9_999_800_001</output>

<gadget id="calculator">9_999_800_001 + 9_999_800_001 + 99_999</gadget>
<output>19_999_700_001</output>

<result>19_999_700_001</result>