Calculation: 100-96+92-88+...+12-8+4=how much.
计算：100-96+92-88+…+12-8+4=多少．
<gadget id="calculator">4 * 12</gadget>
<output>48</output>

<gadget id="calculator">48 + 4</gadget>
<output>52</output>

<result>52</result>