public class Cas {
    public static void main(String[] args) {
       Father f = new Father();
       f.print();

       f = new Son();
       f.print();
    }
}

class Father {
    void print() {
        System.out.println("Father");
    }
}
class Son extends Father {
    void print() {
        System.out.println("Son");
    }
}