1978*298129812981-2980*197719771977=
1978*298129812981-2980*197719771977=
<gadget id="calculator">1_978 * 298_129_812_981</gadget>
<output>589_700_770_076_418</output>

<gadget id="calculator">2_980 * 197_719_771_977</gadget>
<output>589_204_920_491_460</output>

<gadget id="calculator">589_700_770_076_418 - 589_204_920_491_460</gadget>
<output>495_849_584_958</output>

<result>495_849_584_958</result>