2

public interface Guancha {
    public void sheng();
    public void jiang();
}

public class Gumin implements Guancha{
    private String name;
    public Gumin(String a){name=a;}
    public void sheng(){
        System.out.println(name+"买了一些股票（股票升了）");
    }
    public void jiang(){
        System.out.println("股票降价了，哭了");
    }
}

public class main {
    public static void main(String[] args) {
        Fen f=new Fen();
        Gumin g1=new Gumin("第一个股民");
        Gumin g2=new Gumin("第二个股民");
        f.add(g1);
        f.add(g2);
        System.out.println("股票升了");
        f.sheng(0.1);
        System.out.println("比率小于0.05");
        System.out.println();
        f.sheng(0.001);

        System.out.println("股票降了");
        f.jiang(0.1);
        System.out.println("比率小于0.05");
        System.out.println();
        f.jiang(0.001);
    }
}