((9999*9999)/(9*9)).
((9999*9999)/(9*9))．
<gadget id="calculator">9_999 * 9_999</gadget>
<output>99_980_001</output>

<gadget id="calculator">9 * 9</gadget>
<output>81</output>

<gadget id="calculator">99_980_001 / 81</gadget>
<output>1_234_321</output>

<result>1_234_321</result>