using System;

public class Program

{

    public static void Main(string[] args)

    {

            decideWhich();

        }

​

        public static void Frequency()

        {

            try

            {

                decimal num = 3000000000000000000;

                num = num * 10;

                Console.WriteLine("Enter Frequency(Hz) value from <3000000000 to >30000000000000000000. ");

                Console.Write("Frequency: ");

                decimal a = decimal.Parse(Console.ReadLine());

​

                if (a < 3000000000) { Console.WriteLine("Type: Radio Waves\tWavelength(m): >10^-1"); }

                else if (a >= 3000000000 && a <= 300000000000)

                { Console.WriteLine("Type: Microwaves\tWavelength(m): <10^-3 to 10^-1"); }

                else if (a > 300000000000 && a <= 400000000000000)

                { Console.WriteLine("Type: Infrared\tWavelength(m): <7x10^-7 to 10^-3"); }

                else if (a > 400000000000000 && a <= 750000000000000)

                { Console.WriteLine("Type: Visible Light\tWavelength(m): <4x10^-7 to 7x10^-7"); }

                else if (a > 750000000000000 && a <= 30000000000000000)

                { Console.WriteLine("Type: Ultraviolet\tWavelength(m): <10^-8 to 4x10^-7"); }

                else if (a > 30000000000000000 && a <= num)

                { Console.WriteLine("Type: X-Rays\tWavelength(m): 10^-11 to 10^-8"); }

                else { Console.WriteLine("Type: Gamma Rays\tWavelength(m): <10^-11"); }

                Console.WriteLine("===================================================================");

                endLoop();

            }

            catch(Exception )

            {

                Console.WriteLine("========================================================\n" +

                       "PLEASE ENTER VALID VALUE!");

                Frequency();

            }

​

        }

​

        public static void Wavelength()

        {

            try 

            {

                Console.WriteLine("Enter WaveLength(m) value from >0.1 to <0.00000000001. ");

                Console.Write("WaveLength: ");

                double  a = Convert.ToDouble(Console.ReadLine());

​

                if (a > 0.1) { Console.WriteLine("Type: Radio Waves\tFrequency(Hz):<3x10^9"); }

                else if (a > 0.001 && a <= 0.1)

                { Console.WriteLine("Type: Microwaves\tFrequency(Hz): 3x10^9 to 3x10^11"); }

                else if (a > 0.0000007 && a <= 0.001)

                { Console.WriteLine("Type: Infrared\tFrequency(Hz): >3x10^11 to 4x10^14"); }

                else if (a > 0.0000004 && a <= 0.0000007)

                { Console.WriteLine("Type: Visible Light\tFrequency(Hz): >4x10^14 to 7.5x10^14"); }

                else if (a > 0.00000001 && a <= 0.0000004)

                { Console.WriteLine("Type: Ultraviolet\tFrequency(Hz): >7.5x10^14 to 3x10^16"); }

                else if (a >= 0.00000000001 && a <= 0.00000001)

                { Console.WriteLine("Type: X-Rays\tFrequency(Hz): >3x10^16 to 3x10^19"); }

                else { Console.WriteLine("Type: Gamma Rays\tFrequency(Hz): >3x10^19"); }

                Console.WriteLine("========================================================");

                endLoop(); 

            }

            catch(Exception)

            {

                Console.WriteLine("========================================================\n" +

                        "PLEASE ENTER VALID VALUE!");

                Wavelength();

            }

        }

​

        public static void decideWhich()

        {

            Console.WriteLine("What do you want to Input?");

            Console.Write("WaveLength or Frequency? ");

            string ask = Convert.ToString(Console.ReadLine());

            if (ask == "Wavelength" || ask == "wavelength" || ask == "WAVELENGTH")

            {

                Console.WriteLine("\n===================================================================");

​

                Wavelength();

            }

            else if (ask == "Frequency" || ask == "frequency" || ask == "FREQUENCY")

            {

                Console.WriteLine("\n===================================================================");

​

                Frequency();

            }

            else { Console.WriteLine("\nPlease Enter  Valid Choice!"); decideWhich(); }

​

        }

​

​

        public static void endLoop()

        {

            Console.Write("\nEnter Value Again? Y or N? ");

            char yesNo = Convert.ToChar(Console.ReadLine());

            if (yesNo == 'y' || yesNo == 'Y')

            {

                Console.WriteLine();

                decideWhich();

            }

            else if (yesNo == 'n' || yesNo == 'N')

            {

                //PROGRAM ENDS

            }

            else if (yesNo != 'n' || yesNo != 'N' || yesNo != 'y' || yesNo != 'Y')

            {

                Console.WriteLine("Enter Valid Choice!");

                endLoop();

            }

        }

}

​