There is a red straight line with a length of 100 cm on the table, and there are several circular pieces of paper with diameters of 2, 3, 7, and 15 cm. Now use these circular pieces of paper to cover the red line on the table. If you want If the sum of the circumferences of the pieces of paper used is the shortest, what is the sum of the circumferences?
桌面上有一条长度为100厘米的红色直线，另外有直径分别是2、3、7、15厘米的圆形纸片若干个，现在用这些圆形纸片将桌上的红线盖住，如果要使所用纸片的圆周长总和最短，那么这个周长总和是多少．
<gadget id="calculator">3.14 * 100</gadget>
<output>314</output>

<result>314</result>