public static void Main()
new Printer().Print(new Contain());
public interface ISecond{
public class Contain : IFirst, ISecond{
public string First{get{return "I AM FIRST";} set{}}
public string Second{get{return "I AM SECOND";} set{}}
public void Print(IFirst first){
Console.WriteLine(first.First);
public void Print(ISecond second){
Console.WriteLine(second.Second);