If a cylinder viewed from the front is a square with a side length of 4 cm, what is the volume of the cylinder in cubic centimeters?
一个圆柱从正面看它的平面图是一个边长为4厘米的正方形，那么这个圆柱的体积是多少立方厘米．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 4 * 4</gadget>
<output>50.24</output>

<result>50.24</result>