A cylindrical pillar is wrapped around its base with a rope, its length is 3.14 meters, and its height is 4 meters. What is the volume of this pillar?
一个圆柱形柱子，用绳绕它的底面一周长3.14米，高4米，这根柱子的体积是多少．
<gadget id="calculator">3.14 / 3.14 / 2</gadget>
<output>0.5</output>

<gadget id="calculator">0.5 ** 2</gadget>
<output>0.25</output>

<gadget id="calculator">3.14 * 0.25 * 4</gadget>
<output>3.14</output>

<result>3.14</result>