Calculation: 20*20+19*19+2*2+1*1.
计算：20*20+19*19+2*2+1*1．
<gadget id="calculator">20 * 20</gadget>
<output>400</output>

<gadget id="calculator">19 * 19</gadget>
<output>361</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">1 * 1</gadget>
<output>1</output>

<gadget id="calculator">400 + 361 + 4 + 1</gadget>
<output>766</output>

<result>766</result>