Calculate with a simple method: 2011*2012-2010*2013.
用简便方法计算：2011*2012-2010*2013．
<gadget id="calculator">2_011 * 2_012</gadget>
<output>4_046_132</output>

<gadget id="calculator">2_010 * 2_013</gadget>
<output>4_046_130</output>

<gadget id="calculator">4_046_132 - 4_046_130</gadget>
<output>2</output>

<result>2</result>