There are 40 students in the third grade participating in the gymnastics performance. If they want to stand in a square team, at least how many people must be removed.
三年级有40名学生参加体操表演，如果要站成方队，至少要去掉多少人．
<gadget id="calculator">40 - 36</gadget>
<output>4</output>

<result>4</result>