using System;

public class Program

{

    interface IInterface1

    {

        void Method();

    }

    interface IInterface2:IInterface1

    {

        new void Method();

    }

    class ConcreteClass:IInterface2

    {

        void IInterface1.Method()

        {       

            Console.WriteLine("Реализация метода IInterface1");             

        }

        void IInterface2.Method()

        {

            Console.WriteLine("Реализация метода IInterface2");

        }

    }

    public static void Main()

    {

        ConcreteClass instance = new ConcreteClass();

        IInterface1 instance1 = instance as IInterface1;

        instance1.Method();

        IInterface2 instance2 = instance as IInterface2;

        instance2.Method();

    }

}