The school has a total of 35 balls, Class 21 borrowed 5 balls, and Class 22 borrowed 8 balls. How many balls are left?
学校一共有35个球，二1班借走了5个，二2班借走了8个．还剩几个球？
<gadget id="calculator">35 - 5 - 8</gadget>
<output>22</output>

<result>22</result>