Calculation: (1+2)+(3+7+11+...+99)=how much.
计算：(1+2)+(3+7+11+…+99)=多少．
<gadget id="calculator">3 + 99</gadget>
<output>102</output>

<gadget id="calculator">99 - 3</gadget>
<output>96</output>

<gadget id="calculator">96 / 4</gadget>
<output>24</output>

<gadget id="calculator">24 + 1</gadget>
<output>25</output>

<gadget id="calculator">25 / 2</gadget>
<output>25/2 = around 12.5</output>

<gadget id="calculator">102 * (25/2)</gadget>
<output>1_275</output>

<gadget id="calculator">3 + 1_275</gadget>
<output>1_278</output>

<result>1_278</result>