Divide a circle with a radius of 1 decimeter into several parts, cut them out and assemble them into an approximate rectangle. What is the perimeter of this rectangle in decimeters.
把一个半径是1分米的圆平均分成若干份，剪开拼成一个近似的长方形．这个长方形的周长是多少分米．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

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

<gadget id="calculator">3.14 + 1</gadget>
<output>4.14</output>

<gadget id="calculator">4.14 * 2</gadget>
<output>8.28</output>

<result>8.28</result>