Use iron wire to tie two logs with a cross-sectional diameter of 20 cm together. If the length of the iron wire at the joint is 5 cm, how many centimeters of iron wire are needed for one round of binding?
用铁丝把2根横截面直径都是20厘米的圆木捆在一起，如果接头处铁丝长5厘米，那么捆一周至少需要多少厘米的铁丝．
<gadget id="calculator">20 * 2</gadget>
<output>40</output>

<gadget id="calculator">3.14 * 20</gadget>
<output>62.8</output>

<gadget id="calculator">40 + 62.8 + 5</gadget>
<output>107.8</output>

<result>107.8</result>