using System;

class B
{
    public virtual void Foo(int x)
    {
        Console.WriteLine(1);
    }

    public virtual void Foo(long x, long y = 1)
    {
        Console.WriteLine(2);
        Console.WriteLine(y);
    }

    public virtual void Foo(object x)
    {
        Console.WriteLine(3);
    }
}

class C : B
{
    public override void Foo(int y)
    {
        Console.WriteLine(4);
    }

    public override void Foo(object x)
    {
        Console.WriteLine(5);
    }
}

class D : C
{
    public override void Foo(int x)
    {
        Console.WriteLine(6);
    }

    public override void Foo(long a, long b = 2)
    {
        Console.WriteLine(7);
        Console.WriteLine(b);
    }

    public override void Foo(object x)
    {
        Console.WriteLine(8);
    }


    static void Main()
    {
        C c = new D();
        c.Foo(x:1);
    }
}