using System;

​

public class Program

{

    public static ulong Power(ulong a, ulong n)

    {

        ulong result = 1;

        for (ulong i = 0; i < n; i++)

        {

            result = Multiply(result, a);

        }

​

        return result;

    }

​

    public static ulong Multiply(ulong a, ulong n)

    {

        ulong result = 0;

        for (ulong j = 0; j < n; j++)

        {

            result = result + a;

        }

​

        return result;

    }

​

    public static void Main()

    {

        for (ulong n = 2; n < 5; n++)

        {

            for (ulong a = 2; a < 10; a++)

            {

                //var expected = a * n;

                //var result = Multiply(a, n);

                var expected = Math.Pow(a, n);

                var result = Power(a, n);

                Console.WriteLine("{0}   {1}   {2}", result, expected, result == expected);

            }

        }

    }

}