The length of one side of an isosceles right triangle is 8 cm, and two semicircles are drawn with the two sides as diameters, then, how many square centimeters are the areas of the shaded parts?
等腰直角三角形的一腰长是8厘米，以它的两腰为直径分别画两个半圆，那么，阴影部分的面积共有多少平方厘米．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16</gadget>
<output>50.24</output>

<gadget id="calculator">8 * 4</gadget>
<output>32</output>

<gadget id="calculator">50.24 - 32</gadget>
<output>18.24</output>

<result>18.24</result>