Divide a circle into several equal parts and assemble them into an approximate rectangle. The width of the assembled approximate rectangle is 1 cm. What is the area of the original circle in square centimeters?
将一个圆平均分成若干份，拼成一个近似长方形，拼成的近似长方形的宽是1厘米，原来圆的面积是多少平方厘米．
<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

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

<result>3.14</result>