200+199-198+197-196+...+5-4+3-2+1.
200+199-198+197-196+…+5-4+3-2+1．
<gadget id="calculator">200 - 2</gadget>
<output>198</output>

<gadget id="calculator">198 / 2</gadget>
<output>99</output>

<gadget id="calculator">1 * 99</gadget>
<output>99</output>

<gadget id="calculator">200 + 99 + 1</gadget>
<output>300</output>

<result>300</result>