using System;

public class Program

{

    class BaseClass

    {

        public int baseNumber;

        public BaseClass()

        {

        }

        public BaseClass(int number)

        {

            this.baseNumber = number;

        }

    }

    class DerivedClass:BaseClass

    {

        public int derivedField;

        public DerivedClass()

        {           

        }

        public DerivedClass(int number1, int number2) 

            : base (number1)

        {

            derivedField = number2;

        }

    }

    public static void Main()

    {

        DerivedClass instance = new DerivedClass(1,2);

        Console.WriteLine(instance.baseNumber);

        Console.WriteLine(instance.derivedField);

    }

}