using System;

​

namespace ConsoleApp14

{

    public class Program

    {

        public double Power(double number, double raiseToPower)

        {

            double result = 0;

            if (raiseToPower < 0)

            {

                raiseToPower *= -1;

                result = 1 / number;

                for (int i = 1; i < raiseToPower; i++)

                {

                    result /= number;

                }

            }

            else if (raiseToPower == 0)

            {

                result = 1;

            }

            else

            {

                result = number;

                for (int i = 1; i < raiseToPower; i++)

                {

                    result *= number;

                }

            }

            return result;

        }

        public double NthRoot(double A, int N)

        {

           double epsilon = 0.00001;//

           double n = N;

           double x = A / n;

           while (Module(A - Power(x,N)) > epsilon)

           {

                x = (1/n) * ((n-1)*x + (A/(Power(x, N-1))));

           }

           return x;

        }

        public double Module (double X) {

            double result;

            if (X < 0) {

                result = X*(-1);

            }

            else {

                result = X;

            }

            return result;

        }

        public double MiddleGeometric(int[] massiv)

        {

            int dobutok = 1;

            int arrayLength = massiv.Length;

            for (int i=0; i<arrayLength; i++)

            {

                dobutok *= massiv[i];

            }

            double midGem = NthRoot(dobutok, arrayLength);

            return midGem;

        }

        public static void Main(string[] args)

        {

            int[] a1 = new int[] { 10, 2, 3, 4, 5 };

            int[] a2 = new int[] { 7, 2, 3, 4, 42 };

            int[] a3 = new int[] { 8, 2, 3, 4, 9 };

            Program p = new Program();

            double midA1 = p.MiddleGeometric(a1);

            double midA2 = p.MiddleGeometric(a2);

            double midA3 = p.MiddleGeometric(a3);

            Console.WriteLine("serednie geometrychne 1 - {0}\nserednie geometrychne 2 - {1}\nserednie geometrychne 3 - {2}",midA1,midA2,midA3);

            if (midA1 < midA2 && midA1 < midA3)

            {

                Console.WriteLine("naymenshe serednie geometrychne - {0}", midA1);

            }

            else {

                if (midA2 < midA3)

                {

                    Console.WriteLine("naymenshe serednie geometrychne - {0}", midA2);

                }

                else { Console.WriteLine("naymenshe serednie geometrychne - {0}", midA3);

                     }

            }

        }

    }

}

​