The circumference of the base of a cylinder is equal to the height, if the height is shortened by 2 cm, the surface area is reduced by 12.56 cm2. Find the surface area of this cylinder.
一个圆柱体底面周长和高相等，如果高缩短了2厘米，表面积就减少12.56平方厘米．求这个圆柱体的表面积．
<gadget id="calculator">6.28 * 6.28</gadget>
<output>39.4384</output>

<gadget id="calculator">2 * 3.14</gadget>
<output>6.28</output>

<gadget id="calculator">6.28 / 6.28</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1 * 2</gadget>
<output>6.28</output>

<gadget id="calculator">39.4384 + 6.28</gadget>
<output>45.7184</output>

<result>45.7184</result>