public class Driver {
    public static void main(String [] args) {
        P p1 = new P();
        p1.m();
        p1.m(12);
        p1.m2();

        C c1  = new C();
        c1.m();
        c1.m(12);
        c1.m2();
        c1.m2(21);
        ((P) c1).m();
    }
}