A class of 35 people visited the Shanghai World Expo. It is known that there are 23 boys in this class. How much more girls in this class have visited the World Expo than the boys who have not visited the Expo.
某班有35人参观了上海世博会．已知这个班共有男生23人，该班参观世博会的女生比没有参观世博会的男生多多少人．
<gadget id="calculator">35 - 23</gadget>
<output>12</output>

<result>12</result>