using System;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Running Tests...");

        Tests.Run();

        Console.WriteLine("...Tests Complete");

    }

}

​

public static class Tests

{

    public static void Run()

    {

        //Setup()

        TestNumberOfLines();

        TestFirstLineIsOne();

        //TestThirdLineIsFizz();

        //TestFifthLineIsBuzz();

        //TestNinetiethLineIsFizzBuzz();

        //TestSeventhLineIsSeven();

    }

​

    private static void TestNumberOfLines()

    {

        var fb = new FizzBuzz();

        var result = fb.Run();

        var length = result.Trim().Split('\r').Length;

        Assert(length == 100, length.ToString());

    }

​

    private static void TestFirstLineIsOne()

    {

        var fb = new FizzBuzz();

        var result = fb.Run();

        var shouldBeOne = result.Trim().Split('\r')[0].Trim();

        Assert(shouldBeOne == "1", shouldBeOne);

    }

​

    private static void Assert(bool condition, string msg)

    {

        if (!condition)

        {

            throw new Exception(msg);

        }

    }

}

​

public class FizzBuzz

{

    public string Run()

    {

        var strOut = "";

        for (var i = 1; i <= 100; i++)

        {

            strOut += i.ToString();

            strOut += Environment.NewLine;

        }

​

        return strOut;

    }

}