Find the sum of 1+2+3+...+198+199+200.
求1+2+3+…+198+199+200的和．
<gadget id="calculator">1 + 200</gadget>
<output>201</output>

<gadget id="calculator">200 / 2</gadget>
<output>100</output>

<gadget id="calculator">201 * 100</gadget>
<output>20_100</output>

<result>20_100</result>