Kindergarten children stand on a square field to play games, with 10 children standing on each side, and 1 child standing on each of the four vertices. Ask how many children are playing games?
幼儿园小朋友站在一块正方形场地上做游戏，每边都站了10名小朋友，并且四个顶点上都站1名小朋友．问共有多少名小朋友在做游戏？
<gadget id="calculator">10 * 4</gadget>
<output>40</output>

<gadget id="calculator">40 - 4</gadget>
<output>36</output>

<result>36</result>