using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        var program = new Program();

        program.Run();

    }

​

    public void Run()

    {

        Console.WriteLine(ConditionalConcatenate("ORIGIN", "TARIFF NUMBER"));

        Console.WriteLine(ConditionalConcatenate("", "TARIFF NUMBER"));

        Console.WriteLine(ConditionalConcatenate("ORIGIN", ""));

        Console.WriteLine(ConditionalConcatenate("", ""));

        Console.WriteLine(ConditionalConcatenate("ORIGIN", "TARIFF NUMBER"));

        Console.WriteLine(ConditionalConcatenate(null, "TARIFF NUMBER"));

        Console.WriteLine(ConditionalConcatenate("ORIGIN", null));

        Console.WriteLine(ConditionalConcatenate(null, null));

    }

​

    // You can use this method for both: The calculation of title and the calculation of the values

    public string ConditionalConcatenate(string origin, string tariffNumber)

    {

        return string.Join(" / ", ExtractElementsNotNullOrEmpty(origin, tariffNumber));

    }

​

    public IEnumerable<string> ExtractElementsNotNullOrEmpty(params string[] elements)

    {

        return elements.Where(x => !string.IsNullOrEmpty(x));

    }

}