用Java map和list集合写一个省市区的增删改查

非常好的问题！以下是一个使用Java map和list集合实现省市区增删改查的示例代码：

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class ProvinceCityArea {

    private Map<String, List<String>> provinceCityMap;

    public ProvinceCityArea() {
        provinceCityMap = new HashMap<>();
    }

    public void addProvince(String province) {
        provinceCityMap.put(province, new ArrayList<>());
    }

    public void addCity(String province, String city) {
        List<String> cities = provinceCityMap.get(province);
        if (cities != null) {
            cities.add(city);
        }
    }

    public void addArea(String province, String city, String area) {
        List<String> cities = provinceCityMap.get(province);
        if (cities != null) {
            int index = cities.indexOf(city);
            if (index >= 0) {
                List<String> areas = new ArrayList<>(cities.subList(index + 1, cities.size()));
                areas.add(area);
                cities.subList(index + 1, cities.size()).clear();
                cities.addAll(areas);
            }
        }
    }

    public void removeProvince(String province) {
        provinceCityMap.remove(province);
    }

    public void removeCity(String province, String city) {
        List<String> cities = provinceCityMap.get(province);
        if (cities != null) {
            cities.remove(city);
        }
    }

    public void removeArea(String province, String city, String area) {
        List<String> cities = provinceCityMap.get(province);
        if (cities != null) {
            int index = cities.indexOf(city);
            if (index >= 0) {
                List<String> areas = new ArrayList<>(cities.subList(index + 1, cities.size()));
                areas.remove(area);
                cities.subList(index + 1, cities.size()).clear();
                cities.addAll(areas);
            }
        }
    }

    public List<String> getCities(String province) {
        return provinceCityMap.get(province);
    }

    public List<String> getAreas(String province, String city) {
        List<String> cities = provinceCityMap.get(province);
        if (cities != null) {
            int index = cities.indexOf(city);
            if (index >= 0) {
                return cities.subList(index + 1, cities.size());
            }
        }
        return null;
    }

}

这个类使用了一个Map来存储省份和城市的关系，每个省份对应一个List，其中存储了该省份下的所有城市。每个城市也对应一个List，其中存储了该城市下的所有区域。可以使用addProvince、addCity、addArea、removeProvince、removeCity、removeArea、getCities和getAreas方法来增加、删除和查询省份、城市和区域。