It is known that |3m-12|+(((n)/2)+1)**2=0, then 2m-n=how much.
已知|3m-12|+(((n)/2)+1)**2=0，则2m-n=多少．
<gadget id="calculator">2 * 4</gadget>
<output>8</output>

<gadget id="calculator">8 + 2</gadget>
<output>10</output>

<result>10</result>