using System;

public class Program

{

    public const string FifteenKg = "15kg";

    public const string TwentyThreeKg = "23kg";

    public static void Main()

    {

        Console.WriteLine("==Beach");

        Console.WriteLine(GetBaggage(false, false, "BO"));  //23

        Console.WriteLine(GetBaggage(true, false, "BO"));   //23

        Console.WriteLine(GetBaggage(false, true, "BO"));   //23

        Console.WriteLine(GetBaggage(true, true, "BO"));    //23

        Console.WriteLine();

        Console.WriteLine("==Ext flight - UK");

        Console.WriteLine(GetBaggage(true, true, "CO"));    //15

        Console.WriteLine(GetBaggage(true, true, "CV"));    //15

        Console.WriteLine(GetBaggage(true, true, "CX"));    //?

        Console.WriteLine();

        Console.WriteLine("==Ext flight - non-UK");

        Console.WriteLine(GetBaggage(true, false, "CO"));   //15

        Console.WriteLine(GetBaggage(true, false, "CV"));   //15

        Console.WriteLine(GetBaggage(true, false, "CX"));   //?

        Console.WriteLine();

        Console.WriteLine("==Int - UK");

        Console.WriteLine(GetBaggage(false, true, "CO"));   //23

        Console.WriteLine(GetBaggage(false, false, "CO"));  //23

        Console.WriteLine(GetBaggage(false, true, "CV"));   //23

        Console.WriteLine(GetBaggage(false, false, "CV"));  //23

        Console.WriteLine(GetBaggage(false, true, "CX"));   //23

        Console.WriteLine(GetBaggage(false, false, "CX"));  //23

    }

    public static string GetBaggage(bool isExt, bool isUk, string promo)

    {

        var baggageType = "not-defined";

​

        if(isExt)

        {

            if(isUk)

            {

                if(promo.Equals("CO") || promo.Equals("CV"))

                {

                    baggageType = "15kg";

                }

                else if(promo.StartsWith("B"))

                {

                    baggageType = "23kg";

                }

            }

            else if(!isUk)

            {

                if(promo.StartsWith("B"))

                {

                    baggageType = "23kg";

                }

            }

    }

    else

    {

        baggageType = "23kg";

    }

    return baggageType;

    }

}