Three ships arrive at the pier at the same time to unload the cargo. It takes 8 hours to unload the cargo on ship A, 4 hours to unload the cargo on ship B, and 1 hour to unload the cargo on ship C. In order to minimize the sum of the waiting times of the three ships, in what order should the cargo be unloaded? What is the minimum time?
有三艘船同时到达码头卸货，A船卸完货要8小时，B船卸完货要4小时，C船卸完货要1小时．要使三艘船的等候时间的总和最少，应该按怎样的顺序卸货？最少时间是多少？
<gadget id="calculator">1 * 3</gadget>
<output>3</output>

<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<gadget id="calculator">3 + 8 + 8</gadget>
<output>19</output>

<result>19</result>