There are 50 students in the class, among them 22 are fond of mathematics, 22 are fond of music, 22 are fond of sports, 6 are fond of all three, and 8 are not fond of them. How many people are there?
全班有50个人，其中爱好数学的有22人，爱好音乐的有22人，爱好体育的有22人，三样都爱好的有6人，都不爱好的有8人，问只爱一样的有几人？
<gadget id="calculator">50 - 8</gadget>
<output>42</output>

<gadget id="calculator">22 * 3</gadget>
<output>66</output>

<gadget id="calculator">66 - 42 - 6</gadget>
<output>18</output>

<gadget id="calculator">42 - 18</gadget>
<output>24</output>

<result>24</result>