import java.util.*;

public class Main {
    public static void main(String[] args) {
        Hebele hebele1 = new Hebele();
        Hebele hebele2 = new Hebele();
        Hubele hubele1 = new Hubele();
        Hebele hebele3 = new Hubele();
        hebele1.setA("A");
        hebele2.setA(123);
        hubele1.setA(42d);
        hebele3.setA(456);
        System.out.println(hebele1.getA());
        System.out.println(hebele2.getA());
        System.out.println(hubele1.getA());
        System.out.println(hebele3.getA());
        List<Object> liste = List.of("a","b", 1);
        System.out.println(liste);
        // System.out.println("a" instanceof Object);
    }

}

class Hebele {
    private Object a;

    public Object getA() {
        return a;
    }

    public void setA(Object a) {
        this.a = a;
    }
}

class Hubele extends Hebele {
    public Object getA() {
        System.out.println("???");
        return super.getA();
    }
}