A class of 52 people is doing Chinese and math homework. 32 people finished their Chinese homework, and 35 people finished their math homework. How many people have finished their Chinese and math homework?
一个班的52人都在做语文和数学作业．有32人做完了语文作业，有35人做完了数学作业．语文、数学作业都做完的有多少人？
<gadget id="calculator">35 - 52</gadget>
<output>-17</output>

<gadget id="calculator">32 + (-17)</gadget>
<output>15</output>

<result>15</result>