import java.util.*;

public class Main
{
    public static void main (String[]args)
    {
        System.out.println (A.VAR_A);
        System.out.println (B.list);
    }
}

class A
{
    public static final String VAR_A = B.id ("A");
    public static final String VAR_B = "B";
}

class B
{
    public static final List < String > list = new ArrayList <> ();
    static
    {
        list.add (A.VAR_A);
        list.add (A.VAR_B);
    }

    public static String id (String s)
    {
        return s;
    }
}