using System;

​

public class Program

{

    static private long fact(long a) //FACTORIAL

    {

        long factorial = 1;

        long i = 1;

        do

        {

            factorial = factorial * i;

            i++;

        }

        while (i <= a);

        return factorial;

    }

    static private long perm (long n, long r) //PERMUTATION

    {

        long step1 = n-r;

        long step2 = (fact(n));

        long step3 = (fact(step1));

        long step4 = step2 / step3;

        return step4;

    }

    static private long com (long n, long r) //COMBINATION

    {

        long step1 = (n-r);

        long step2 = (fact(n));

        long step3 = (fact(r));

        long step4 = (fact(step1));

        long step5 = step3 * step4;

        long step6 = step2 / step5;

        return step6;

    }

    static private double dp(double a) //DECIMAL TO PERCENT

    {

        double p = a*100;

        return p;

    }

    static private double pd(double a) //PERCENT TO DECIMAL

    {

        double d = a/100;

        return d;

    }

static private double mean(int A, double a, double b, double c, double d, double e, double f, double g, double h, double i, double j) //MEAN

    {

        if (A == 2)

        {double mean2 = (a+b)/2;

         return mean2;

        }

    else if (A == 3)

        {double mean3 = (a+b+c)/3;

         return mean3;

        }

        if (A == 4)

        {double mean4 = (a+b+c+d)/4;

         return mean4;

        }

        if (A == 5)

        {double mean5 = (a+b+c+d+e)/5;

         return mean5;

        }

        if (A == 6)

        {double mean6 = (a+b+c+d+e+f)/6;

         return mean6;

        }

        if (A == 7)

        {double mean7 = a+b+c+d+e+f+g/7;

         return mean7;

        }

        if (A == 8)

        {double mean8 = a+b+c+d+e+f+g+h/8;

         return mean8;

        }

        if (A == 9)

        {double mean9 = a+b+c+d+e+f+g+h+i/9;

         return mean9;

        }

        if (A == 10)

        {double mean10 = a+b+c+d+e+f+g+h+i+j/10;

         return mean10;

        }

    }

​

    public static void Main()

    {

        string choice = "This value doesn't matter";

        while (choice != "n" && choice != "N")

        {

            Console.WriteLine("Hello and Welcome to My Probability Calculator!  Please Choose an option from the menu!");

            Console.WriteLine("If you would like to calculate n!, please press 1.");

            Console.WriteLine("If you would like to calculate nPr, please press 2.");

            Console.WriteLine("If you would like to calculate nCr, please press 3. ");

            Console.WriteLine("If you would like to convert a decimal to a percent, please press 4.");

            Console.WriteLine("If you would like to convert a percent to a decimal, please press 5.");

            Console.WriteLine("If you would like to find the median of a set of numbers, please press 6.");

            int input;

            string sinput = Console.ReadLine();

            if (int.TryParse(sinput, out input))

            {

                if (input == 1) //FACTORIAL

                {Console.WriteLine("What number would you like to see the factorial of?");

                 long finput = long.Parse(Console.ReadLine());

                    Console.WriteLine("The factorial of " +finput+ " is "+ fact(finput));

                }

                if (input == 2) //PERMUTATION

                {Console.WriteLine("Enter n");

                 long Pinputn = long.Parse(Console.ReadLine());

                 Console.WriteLine("Enter r");

                 long Pinputr = long.Parse(Console.ReadLine());

                 Console.WriteLine("The permutation in which n="+Pinputn+ " and r="+Pinputr+" is "+perm(Pinputn, Pinputr));

                }

                if (input == 3)//COMBINATION

                {Console.WriteLine("Enter n");

                 long Cinputn = long.Parse(Console.ReadLine());

                 Console.WriteLine("Enter r");

                 long Cinputr = long.Parse(Console.ReadLine());

                 Console.WriteLine("The combination in which n="+Cinputn+ " and r="+Cinputr+" is "+com(Cinputn, Cinputr));

                }

                if (input == 4)//DEC TO PER

                {Console.WriteLine("What decimal would you like to convert?");

                 double dinput = double.Parse(Console.ReadLine());

                 Console.WriteLine(dinput+" as a percent is " + dp(dinput)+"%");

                }

                if (input == 5)//PER TO DEC

                {Console.WriteLine("What percent would you like to convert?");

                 int pinput = int.Parse(Console.ReadLine());

                 Console.WriteLine(pinput+ " as a decimal is " +pd(pinput));

                }

                if (input == 6)//MEAN

                {Console.WriteLine("How many values do you have out of 10?");

                 int amount = int.Parse(Console.ReadLine());

                 Console.WriteLine("Enter the numbers from small to large.");

                 double minput1 = double.Parse(Console.ReadLine());

                 if (amount == 2)

                 {double minput2 = double.Parse(Console.ReadLine());

                  Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2));}

                 if (amount == 3)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                 Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3));}

                 if (amount == 4)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                  double minput4 = double.Parse(Console.ReadLine());

                 Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3,minput4));}

                 if (amount == 5)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                  double minput4 = double.Parse(Console.ReadLine());

                  double minput5 = double.Parse(Console.ReadLine());

                  Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3,minput4,minput5));}

                   if (amount == 6)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                  double minput4 = double.Parse(Console.ReadLine());

                  double minput5 = double.Parse(Console.ReadLine());

                  double minput6 = double.Parse(Console.ReadLine());

                  Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3,minput4,minput5,minput6));}

                   if (amount == 7)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                  double minput4 = double.Parse(Console.ReadLine());

                  double minput5 = double.Parse(Console.ReadLine());

                  double minput6 = double.Parse(Console.ReadLine());

                  double minput7 = double.Parse(Console.ReadLine());

                  Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3,minput4,minput5,minput6,minput7));}

                 if (amount == 8)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                  double minput4 = double.Parse(Console.ReadLine());

                  double minput5 = double.Parse(Console.ReadLine());

                  double minput6 = double.Parse(Console.ReadLine());

                  double minput7 = double.Parse(Console.ReadLine());

                  double minput8 = double.Parse(Console.ReadLine());

                  Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3,minput4,minput5,minput6,minput7,minput8));}

                  if (amount == 9)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                  double minput4 = double.Parse(Console.ReadLine());

                  double minput5 = double.Parse(Console.ReadLine());

                  double minput6 = double.Parse(Console.ReadLine());

                  double minput7 = double.Parse(Console.ReadLine());

                  double minput8 = double.Parse(Console.ReadLine());

                  double minput9 = double.Parse(Console.ReadLine());

                   Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3,minput4,minput5,minput6,minput7,minput8,minput9));}

                  if (amount == 10)

                 {double minput2 = double.Parse(Console.ReadLine());

                  double minput3 = double.Parse(Console.ReadLine());

                  double minput4 = double.Parse(Console.ReadLine());

                  double minput5 = double.Parse(Console.ReadLine());

                  double minput6 = double.Parse(Console.ReadLine());

                  double minput7 = double.Parse(Console.ReadLine());

                  double minput8 = double.Parse(Console.ReadLine());

                  double minput9 = double.Parse(Console.ReadLine());

                  double minput10 = double.Parse(Console.ReadLine());

                  Console.WriteLine("The mean of the above numbers is "+mean(amount,minput1,minput2,minput3,minput4,minput5,minput6,minput7,minput8,minput9,minput10));}

                }

            }

            Console.WriteLine("Would you like to run again? y/n");

            choice = Console.ReadLine();

            Console.Clear();

        }

    }

}