using System;

public class Program

{

     public string firstName;

     public string lastName;

    public Program(string firstName){

            this.firstName = firstName;

            Console.WriteLine("Constr 1");

        }

    public Program(string firstName, string lastName) :this(firstName){

            this.lastName = lastName;

            Console.WriteLine("Constr 2");

        }

    public static void Main()

    {

        var Program = new Program ("first", "second");

        Console.WriteLine(Program.firstName);

        Console.WriteLine(Program.lastName);

    }

}