The second grade selects 40 people to participate in the broadcasting exercise competition. At least how many people can be subtracted to form a square team?
二年级选出40人参加广播操比赛，至少减去几人就能正好排成正方形的队伍？
<gadget id="calculator">40 - 36</gadget>
<output>4</output>

<result>4</result>