Students from class 31 participated in the school sports meeting. 26 people participated in field competitions, 30 people participated in track competitions, 12 people participated in both of the above two items, and 4 students did not participate in these two items. Ask the students in the class how many people?
三1班同学参加学校运动会，参加田赛的有26人，参加径赛的有30人，以上这两项都参加的有12人，这两项都没参加的有4人，问全班有学生多少人？
<gadget id="calculator">30 - 12</gadget>
<output>18</output>

<gadget id="calculator">26 + 18</gadget>
<output>44</output>

<gadget id="calculator">44 + 4</gadget>
<output>48</output>

<result>48</result>