class A { 
	protected int x() {
		return 3;
	}
	public void printX() {
		System.out.println(x());
	}
}
class B extends A {
	public int x() {
		return 4;
	}
}
class Test {
	public static void main(String[] args) {
		A a = new A();
		System.out.println(a.x());
		a.printX();

		B b = new B();
		System.out.println(b.x());
		b.printX();

		A ab = new B();
		System.out.println(ab.x());
		ab.printX();
	}
}