so far

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Assignment_week_1_1
{
    class Program
    {
        private static void RunExerciseOne()
        {
            Console.WriteLine("You successfully ran exercise one!");
            string firstName = "Jonte";
            string lastName = "Adolfsson";
            Console.WriteLine("Hello " + firstName + " " + lastName + "! I'm glad to inform you that you are the test subject of my very first assignment!");
        }
        // Dumförklarad " " = Mellanslag, satt och kliade på den ett tag.
        private static void RunExerciseTwo()
        {
            Console.WriteLine("You successfully ran exercise two!");
            DateTime today = DateTime.Now;
            DateTime tomorrow = today.AddDays(1);
            DateTime yesterday = today.AddDays(-1);
            Console.WriteLine("Todays date is " + today);
            Console.WriteLine("Tomorrows date is " + tomorrow);
            Console.WriteLine("Yesterdays date was " + yesterday);
        }
        // No comment.
        private static void RunExerciseThree()
        {
            Console.WriteLine("You successfully ran exercise three!");
            Console.ForegroundColor = ConsoleColor.White;
            Console.Write("Enter you first name: ");
            string firstname = Console.ReadLine();
            Console.Write("Enter you last name: ");
            string lastname = Console.ReadLine();
            Console.Clear();
            Console.ForegroundColor = ConsoleColor.Green;
            Console.WriteLine("Alright, I will call you " + firstname + " " + lastname + " from now on!");
        }
        // So far so good.
        private static void RunExerciseFour()
        {
            Console.WriteLine("You successfully ran exercise four!");
            String str = "The quick fox jumped Over the DOG";
            Console.ForegroundColor = ConsoleColor.Red;
            Console.WriteLine(str);
            Console.ResetColor();
            Console.WriteLine("Hit any key to fix the issues!");
            Console.ReadKey();
            Console.Clear();
            {
                if (str.Contains("DOG"))            // Replace
                    str = str.Replace("DOG", "LAZY DOG");
                if (str.Contains("quick"))            // Remove
                    str = str.Remove(4, 6);
                if (str.Contains("Over"))            // Substring Tolower
                    str = str.Substring(0, 1) + str.Substring(1).ToLower();
                if (str.Contains("fox"))            // Insert
                    str = str.Insert(4, "brown ");
            }
            Console.ForegroundColor = ConsoleColor.Green;
            Console.WriteLine(str);
        }
        // Försökte använda lite olika metoder utan att behöva göra en ny string
        private static void RunExerciseFive()

        {
            Console.WriteLine("You successfully ran exercise five!");
            Console.ResetColor();
            String str = "Arrays are very common in programming, they look something like: [1,2,3,4,5]";
            Console.ReadLine();
            string substr = str.Substring(65, 11);
            if (substr.Contains("1"))
                substr = substr.Replace("[1,2,3,4,5]", "[1,4,5,6,7,8,9,10]");
            Console.WriteLine(substr);
        }
        // va lite lat, visdomstand gör mig irriterad x(

        private static void RunExerciseSix()
        {
            Console.WriteLine("You successfully ran exercise six!");
            Console.ResetColor();
            var num1 = 1;
            var num2 = 0;
            Console.Write("Enter your first number: ");
            num1 = Convert.ToInt32(Console.ReadLine());
            Console.Write("Enter you second number: ");
            num2 = Convert.ToInt32(Console.ReadLine());
            Console.Clear();
            string biggest = ("The biggest number is: ");
            Console.WriteLine(biggest + Math.Max(num1, num2));
            string smallest = ("The smallest number is: ");
            Console.WriteLine(smallest + Math.Min(num1, num2));
            string difference = ("The difference between the two numbers are: ");
            Console.WriteLine(difference + Math.Abs(num1 - num2));
            string sum = ("The sum of the two numbers are: ");
            Console.WriteLine(sum + Math.Abs(num1 + num2));
            string product = ("The product between the two numbers are: ");
            Console.WriteLine(product + Math.Abs(num1 * num2));
            string ratio = ("The ratio between the two numbers are: ");
            Console.WriteLine(ratio + Math.Abs(num1 / num2));
        }
        // tandvärk all day erry day wooh

        private static void RunExerciseSeven()
        {
            Console.WriteLine("You successfully ran exercise seven!");
            Console.ResetColor();
            {
                double c, cir;
                double PI = 3.14;
                double s, spha, sphv;

                Console.WriteLine("Enter the radius of the circle : ");
                c = Convert.ToDouble(Console.ReadLine());
                cir = PI * c * c;
                Console.WriteLine("Enter the Radius of the Sphere: ");
                s = Convert.ToDouble(Console.ReadLine());
                spha = 4 * PI * s * s;
                sphv = (4.0 / 3) * PI * s * s * s;
                Console.WriteLine("The area of the circle is : {0}", cir);
                Console.WriteLine("The area of the sphere is : {0} ", spha);
                Console.WriteLine("The volume of the sphere is : {0}", sphv);

            }
        }
        // matte ;c

        private static void RunExerciseEight()
        {
            Console.WriteLine("You successfully ran exercise eight!");
            Console.ResetColor();

            {
                double num, sqrt = 0;
                int currentDecimal = 0, dA = 5, iA = 5;

                do
                {
                    Console.Write("Enter a decimal value: ");
                } while (!double.TryParse(Console.ReadLine(), out num));

                while (0 < iA)
                {
                    double currentIncrement = Math.Pow(10, iA);

                    while (Math.Pow(sqrt + currentIncrement, 2) <= num)
                    {
                        sqrt += currentIncrement;
                    }

                    iA--;
                }

                while (currentDecimal <= dA)
                {
                    double currentIncrement = (double)1 / Math.Pow(10, currentDecimal);

                    while (Math.Pow(sqrt + currentIncrement, 2) <= num)
                    {
                        sqrt += currentIncrement;
                    }

                    currentDecimal++;
                }

                Console.WriteLine(("Square root: ") + sqrt);
                Console.WriteLine(("Raised to the power of 2: ") + Math.Pow(num, 2));
                Console.WriteLine(("Raised to the power of 10: ") + Math.Pow(num, 10));
            }
        }
        // Det funkade till slut tror jag

        private static void RunExerciseNine()
        {


            DateTime today = DateTime.Today;
            Console.WriteLine("You successfully ran exercise nine!");
            Console.ResetColor();
            Console.WriteLine("Please enter your name: ");
            string name = (Console.ReadLine());
            while (true)

            {
                Console.WriteLine("Hello " + name + ", please enter your date of birth (MM/DD/YYYY): ");
                DateTime birthDate;

                if (DateTime.TryParse(Console.ReadLine(), out birthDate))
                {
                    TimeSpan age = DateTime.Now - birthDate;
                    var a = (int)(age.Days / 365.25);
                    if (a < 18)
                    {
                        Console.Clear();
                        Console.WriteLine("Would you like to order a coke? (y/n):");
                        string coke = Console.ReadLine();
                        if (coke.Equals("y", StringComparison.OrdinalIgnoreCase) || coke.Equals("yes", StringComparison.OrdinalIgnoreCase))
                        {
                            Console.ForegroundColor = ConsoleColor.Green;
                            Console.WriteLine("A coke has been served!");
                            Console.ResetColor();
                            break;
                        }
                        if (coke.Equals("n", StringComparison.OrdinalIgnoreCase) || coke.Equals("no", StringComparison.OrdinalIgnoreCase))
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("No order options are available!");
                            Console.ResetColor();
                            break;
                        }
                    }
                    else
                        Console.Clear();
                    Console.WriteLine("Would you like to order a beer? (y/n):");
                    string beer = Console.ReadLine();

                    if (beer.Equals("y", StringComparison.OrdinalIgnoreCase) || beer.Equals("yes", StringComparison.OrdinalIgnoreCase))
                    {
                        Console.ForegroundColor = ConsoleColor.Green;
                        Console.WriteLine("A beer has been served!");
                        Console.ResetColor();
                        break;
                    }
                    if (beer.Equals("n", StringComparison.OrdinalIgnoreCase) || beer.Equals("no", StringComparison.OrdinalIgnoreCase))
                    {
                        Console.WriteLine("Would you like to order a coke instead?(y/n):");
                        string coke = Console.ReadLine();
                        if (coke.Equals("y", StringComparison.OrdinalIgnoreCase) || coke.Equals("yes", StringComparison.OrdinalIgnoreCase))
                        {
                            Console.ForegroundColor = ConsoleColor.Green;
                            Console.WriteLine("A coke has been served!");
                            Console.ResetColor();
                            break;
                        }

                        if (coke.Equals("n", StringComparison.OrdinalIgnoreCase) || coke.Equals("no", StringComparison.OrdinalIgnoreCase))
                        {
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("No order options are available!");
                            Console.ResetColor();
                            break;
                        }
                    }

                }

                else
                    Console.ForegroundColor = ConsoleColor.Red;
                Console.WriteLine("You have entered an invalid birthdate, try again." + Environment.NewLine);
                Console.ResetColor();
            }
        }
        // null

        private static void RunExerciseTen()
        {

            var keepAlive = true;
            while (keepAlive)

            {
                try
                {

                    Console.WriteLine("You successfully ran exercise ten!");
                    Console.WriteLine("Input 1 for division.");
                    Console.WriteLine("Input 2 for Exercise 4.");
                    Console.WriteLine("Input 3 for color switch.");
                    Console.WriteLine("Input -1 to exit");
                    var ExerciseTen = int.Parse(Console.ReadLine() ?? "");
                    switch (ExerciseTen)
                    {
                        case 1:
                            Console.ResetColor();
                            var num1 = 1;
                            var num2 = 0;
                            Console.Write("Enter your first number: ");
                            num1 = Convert.ToInt32(Console.ReadLine());
                            Console.Write("Enter you second number: ");
                            num2 = Convert.ToInt32(Console.ReadLine());
                            if (num2 == 0)

                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                                Console.WriteLine("You have entered a invalid number, try again." + Environment.NewLine);
                                Console.ResetColor();
                            }
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Green;
                                Console.WriteLine(num1 + " divided by " + num2 + " is: " + (num1 / num2));
                                Console.ReadKey();
                            }
                            break;
                        case 2:
                            RunExerciseFour();
                            break;
                        case 3:

                            if (Console.ForegroundColor == ConsoleColor.Green)
                            {
                                Console.ForegroundColor = ConsoleColor.Red;
                            }
                            else
                            {
                                Console.ForegroundColor = ConsoleColor.Green;
                            }
                            break;
                        case -1:
                            keepAlive = false;
                            break;
                        default:
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("That is not a valid test number!");
                            break;
                    }
                    Console.WriteLine("Hit any key to continue!");
                    Console.ReadKey();
                    Console.Clear();
                }
                catch
                {
                    Console.ForegroundColor = ConsoleColor.Red;
                    Console.WriteLine("That is not a valid test number!");
                    Console.ResetColor();
                }
            }
        }


        private static void RunExerciseEleven()
        {
            Console.WriteLine("You successfully ran exercise eleven!");
            Console.ResetColor();
            var num1 = 1;

            Console.Write("Enter a number over 0:");
            num1 = Convert.ToInt32(Console.ReadLine());
            if (num1 == 0)

            {
                Console.ForegroundColor = ConsoleColor.Red;
                Console.WriteLine("You have entered a invalid number, try again." + Environment.NewLine);
                Console.ResetColor();

            }


                Console.WriteLine(num1 + 5);
                Console.ReadKey();

        }

        private static void RunExerciseTwelve()
        {
                Console.WriteLine("You successfully ran exercise twelve!");
                Console.ResetColor();

                int start = 1;
                int end = 10;
                for (int i = start; i <= end; i++)
                {
                    for (int j = start; j <= end; j++)
                    {
                        Console.Write("{0,6:d}", (i * j));
                    }
                    Console.WriteLine();
                }
        }
        // Hoppas det duger för uppgiften.
        private static void RunExerciseThirteen()
        {
            Console.WriteLine("You successfully ran exercise eleven!");
            Console.ResetColor();
            Random r = new Random();

            int val = r.Next(1, 500);
            int guess = 0;
            int guessnum = 0;
            bool correct = false;

            Console.WriteLine("I'm thinking of a number between 1-500, can you guess what number it is?");

            while (!correct)
            {
                Console.Write("Guess: ");
                string input = Console.ReadLine();

                if (!int.TryParse(input, out guess))
                {
                    Console.WriteLine("That's not a number, try again.");
                    continue;
                }
                guessnum++;
                if (guess < val)
                {
                    Console.WriteLine("No, the number I'm thinking of is higher than that number.");
                }
                else if (guess > val)
                {
                    Console.WriteLine("No, the number I'm thinking of is lower than that number.");
                }
                else
                {
                    correct = true;
                    Console.ForegroundColor = ConsoleColor.Green;
                    Console.WriteLine("You guessed right and it only took you " + guessnum + " tries!");
                }
            }
        }

        private static void RunExerciseFourteen()
        {
            Console.WriteLine("You successfully ran exercise fourteen!");
            Console.ResetColor();

        }

        private static void RunExerciseTwentyOne()
        {
            Console.WriteLine("You successfully ran exercise twentyone!");
            Console.ResetColor();

        }

        private static void RunTest()  // använder för att lättare testa saker
        {


            //Console.WriteLine("Enter a number: ");
            //int x = int.Parse(Console.ReadLine());
            //double sum = 0;
            //for (int i = 0; i < x; i++)
            //{
            //    Console.WriteLine("Ange tal {0}: ", i);
            //    double number = double.Parse(Console.ReadLine());
            //    sum += number;
            //}

            //Console.WriteLine("Sum of the entered numbers is: {0}", sum);
            //Console.ReadLine();

            //{
            //    Console.WriteLine("Enter the radius of the circle : ");
            //    var c = Convert.ToInt32(Console.ReadLine());


            //    while (c <= 4)
            //    {
            //        Console.WriteLine("Number {0}", c);
            //        c++;
            //    }

            //}

            //string number;
            //double total = 0;
            //int numbers = 0;
            //while ((number = Console.ReadLine()) != "")
            //{
            //    total += double.Parse(number);
            //    numbers++;
            //}

            //Console.WriteLine("The average of the numbers entered is {0}", total / numbers);


    }




        static void Main(string[] args)
        {
            var keepAlive = true;
            while (keepAlive)
            {
                try
                {
                    Console.Write("Enter assignment number (or -1 to exit): ");
                    var assignmentChoice = int.Parse(Console.ReadLine() ?? "");
                    Console.ForegroundColor = ConsoleColor.Green;
                    switch (assignmentChoice)
                    {
                        case 1:
                            RunExerciseOne();
                            break;
                        case 2:
                            RunExerciseTwo();
                            break;
                        case 3:
                            RunExerciseThree();
                            break;
                        case 4:
                            RunExerciseFour();
                            break;
                        case 5:
                            RunExerciseFive();
                            break;
                        case 6:
                            RunExerciseSix();
                            break;
                        case 7:
                            RunExerciseSeven();
                            break;
                        case 8:
                            RunExerciseEight();
                            break;
                        case 9:
                            RunExerciseNine();
                            break;
                        case 10:
                            RunExerciseTen();
                            break;
                        case 11:
                            RunExerciseEleven();
                            break;
                        case 12:
                            RunExerciseTwelve();
                            break;
                        case 13:
                            RunExerciseThirteen();
                            break;
                        case 14:
                            RunExerciseFourteen();
                            break;
                        case 21:
                            RunExerciseTwentyOne();
                            break;
                        case -1:
                            keepAlive = false;
                            break;
                        case 77:                // Använder för att testa saker
                            RunTest();
                            break;
                        default:
                            Console.ForegroundColor = ConsoleColor.Red;
                            Console.WriteLine("That is not a valid assignment number!");
                            break;
                    }
                    Console.ResetColor();
                    Console.WriteLine("Hit any key to continue!");
                    Console.ReadKey();
                    Console.Clear();
                }
                catch
                {
                    Console.ForegroundColor = ConsoleColor.Red;
                    Console.WriteLine("That is not a valid assignment number!");
                    Console.ResetColor();
                }
            }
        }
    }
}