Cut the largest circle out of a square with side length 20 cm, what is the area of the cut part in square centimeters?
在边长20厘米的正方形中剪一个最大的圆，剪去部分的面积是多少平方厘米？
<gadget id="calculator">20 * 20</gadget>
<output>400</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">3.14 * 100</gadget>
<output>314</output>

<gadget id="calculator">400 - 314</gadget>
<output>86</output>

<result>86</result>