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inheritance mystery

Author: Whitaker Brand (on 2018/05/01)

Assume that the following classes have been defined: 

public class Brian extends Lois {
    public void b() {
        a();
        System.out.print("Brian b   ");
    }
    public String toString() {
        return "Brian";
    }
}

public class Lois extends Meg {
    public void a() {
        System.out.print("Lois a   ");
        super.a();
    }
    public void b() {
        System.out.print("Lois b   ");
    }
}

public class Meg {
    public void a() {
        System.out.print("Meg a   ");
    }
    public void b() {
        System.out.print("Meg b   ");
    }
    public String toString() {
        return "Meg";
    }
}

public class Stewie extends Brian {
    public void a() {
        super.a();
        System.out.print("Stewie a   ");
    }
    public String toString() {
        return super.toString() + " Stewie";
    }
}

Given the classes above, what output is produced by the following code? 

Meg[] elements = {new Lois(), new Stewie(), new Meg(), new Brian()};
for (int i = 0; i < elements.length; i++) {
    elements[i].a();
    System.out.println();
    elements[i].b();
    System.out.println();
    System.out.println(elements[i]);
    System.out.println();
}
elements[0]: Lois
elements[1]: Stewie
elements[2]: Meg
elements[3]: Brian

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