Cut a cylinder along its diameter, divide it into equal parts and assemble it into an approximate cuboid. The length of this cuboid is 12.56cm, and the height is 20cm. What is the volume of the cylinder?
一个圆柱沿着直径切开，等分后拼成一个近似的长方体，这个长方体的长是12.56cm，高是20cm圆柱的体积是多少．
<gadget id="calculator">12.56 / 3.14</gadget>
<output>4</output>

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

<gadget id="calculator">3.14 * 16 * 20</gadget>
<output>1_004.8</output>

<result>1_004.8</result>