Divide the residents, summarize each same place, and then list the relationship function between garbage and people and rooms according to the meaning of the question. This is not difficult, but it is too much trouble. I heard that there is a math software package, which I downloaded in English. I don't quite understand. Now I also need to know how to know the distance between each residential area and each garbage station. It's not easy to handle. I didn't find it online.