using System;

using System.Linq;

using System.Globalization;

​

public class Program

{

    public static void Main()

    {

        //modulo

        Enumerable.Range(1, 100).ToList().ForEach(x =>

        {

            var d3 = x % 3;

            var d5 = x % 5;

            Print(d3 == 0, d5 == 0, x);

        });

        //modulo not allowed

        Enumerable.Range(1, 100).ToList().ForEach(x =>

        {

            var d3 = x / 3f == Math.Round(x / 3f);

            var d5 = x / 5f == Math.Round(x / 5f);

            Print(d3, d5, x);

        });

​

        //modulo, round not allowed

        Enumerable.Range(1, 100).ToList().ForEach(x =>

        {

            var d3 = x / 3 * 3 == x;

            var d5 = x / 5 * 5 == x;

            Print(d3, d5, x);

        });

​

        //modulo, round not allowed, nutcase version

        Enumerable.Range(1, 100).ToList().ForEach(x =>

        {

            var d3 = !(x / 3f).ToString().Contains(CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator);

            var d5 = !(x / 5f).ToString().Contains(CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator);

            Print(d3, d5, x);

        });

        //counter loop - no round, %, *, / allowed

        for (int i = 0, three = 0, five = 0; i < 100; i++, three++, five++)

        {

            if (three == 3 && five == 5)

            {

                Console.WriteLine("FizzBuzz");

                three = 0;

                five = 0;

            }

            else if (three == 3)

            {

                Console.WriteLine("Fizz");

                three = 0;

            }

            else if (five == 5)

            {

                Console.WriteLine("Buzz");

                five = 0;

            }

            else

                Console.WriteLine(i);

        }       

    }

    private static void Print(bool three, bool five, int i) {

        if (three && !five)

                Console.WriteLine("Fizz");

            else if (five && !three)

                Console.WriteLine("Buzz");

            else if (five)

                Console.WriteLine("FizzBuzz");

            else

                Console.WriteLine(i);

    }

}