All six grades of a certain elementary school participated in the calligraphy competition, and 20 students from the fifth and sixth grades won prizes. Among the winners in the whole school, there are 18 people who are not in the fifth grade, and 16 people who are not in the sixth grade. How many people have won the calligraphy competition in this school?
某小学六个年级都参加了书法比赛，其中五年级和六年级共20人获奖．在全校获奖者中有18人不是五年级的，有16人不是六年级的．该校书法比赛获奖的总人数是多少人？
<gadget id="calculator">34 - 20</gadget>
<output>14</output>

<gadget id="calculator">14 / 2</gadget>
<output>7</output>

<gadget id="calculator">7 + 20</gadget>
<output>27</output>

<result>27</result>