using System;

public class Program

{

    static private double leg(double c, double a)

    {

        double a2 = a*a;

        double c2= c*c;

        return Math.Sqrt(c2-a2);

    }

    static private double hyp(double a, double b)

    {

        double a2 = a*a;

        double b2 = b*b;

        return Math.Sqrt(a2+b2);

    }

    public static void Main()

    {

        start:

        string restart = "hehe";

        while (restart != "q")

        {

            Console.WriteLine("Would you like to find the hypotenuse (press 2) or a missing leg (press 1) of a right triangle?");

            string choice = Console.ReadLine();

            if (choice == "1")

            {

                leg2:

                Console.WriteLine("Please enter the leg of the triangle");

                double input1 = double.Parse(Console.ReadLine());

                Console.WriteLine("Please enter the hypotnuse");

                double input2 = double.Parse(Console.ReadLine());

                if(input2 < input1)

                {

                    Console.WriteLine("Error leg is bigger than hypotnuse. Please press enter and retry");

                    Console.ReadLine();

                    Console.Clear();

                    goto leg2;

                }

                else

                {

                double output = leg(input2, input1);

                Console.WriteLine("The missing leg is: " + output);

                }

            }

            else if(choice == "2")

            {

                Console.WriteLine("Enter the Length of the 2 legs.");

                double input1 = double.Parse(Console.ReadLine());

                double input2 = double.Parse(Console.ReadLine());

                double output = hyp(input1, input2);

                Console.WriteLine("The hypotenuse is: " + output);

            }

            else

            {

                Console.WriteLine("Error please press enter");

                Console.ReadLine();

                Console.Clear();

                goto start;

            }

            Console.WriteLine("press q to quit or anything else to use the program again.");

            restart = Console.ReadLine();

            Console.Clear();

        }

        Console.WriteLine("Thank you for using this program");

    }

}