Calculation: 13*99+135*999+1357*9999.
计算：13*99+135*999+1357*9999．
<gadget id="calculator">13 * 99</gadget>
<output>1_287</output>

<gadget id="calculator">135 * 999</gadget>
<output>134_865</output>

<gadget id="calculator">1_357 * 9_999</gadget>
<output>13_568_643</output>

<gadget id="calculator">1_287 + 134_865 + 13_568_643</gadget>
<output>13_704_795</output>

<result>13_704_795</result>