A, B, and C take water bottles and go to the faucet to collect water. A, B, and C have to fill up 3, 5, and 4 bottles of water respectively. It is known that it takes 1 minute to fill a bottle of water. How to arrange the order of A, B, and C to fetch water so that the total time they spend is the least? What is the minimum time?
甲乙丙三人拿了水瓶到水龙头前接水，甲乙丙分别要灌满3、5、4瓶水．已知灌满1瓶水需1分钟．怎样安排甲乙丙三人打水的先后顺序，才能使他们所花的总时间最少？最少是多少时间？
<gadget id="calculator">3 * 3</gadget>
<output>9</output>

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

<gadget id="calculator">9 + 8 + 5</gadget>
<output>22</output>

<result>22</result>