public class A
{
    protected int x;

    public A()
    {
        this.x = 9;
        System.out.println("A. x =  " + this.x);
    }
    public A(int x)
    {
        this.x = x;
        System.out.println("A. x =  " + this.x);
    }
    public int getX() { return this.x; }
    public int foo() { return this.x; }
}

public class B extends A
{
    public B() { super(); }
    public B(int x) { super(x); }
    public int foo() { return this.x + 1; }
}

public class C extends B
{
    public C() { super(); }
    public C(int x) { super(x); }
    public int foo() { return this.x + 2; }
    public int bar() { return this.x; }
}

public class D extends C
{
    public D()
    {
        super();
        this.x++;
        System.out.println("D. x = " + this.x);
    }
    public D(int x)
    {
        super(x);
        System.out.println("D. x = " + this.x);
    }
    public D(int x, int y)
    {
        super();
        this.x = this.x + x + y;
        System.out.println("D. x = " + this.x);
    }
    public int foo() { return this.x - 1; }
}

public class E extends C
{
    public E() { super(); }
    public int bar() { return this.x + 1; }
}