The height of a cylinder is reduced by 1cm, and the surface area is reduced by 12.56cm**2. What is the area of the base of the cylinder in cm**2?
一个圆柱体，高减少1cm，表面积减少了12.56cm**2，圆柱体的底面积是多少cm**2．
<gadget id="calculator">12.56 / 1 / 3.14 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<result>12.56</result>