using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(CtoF(0));     

        Console.WriteLine(CtoF(-300));  

        Console.WriteLine(CtoF(28.5));

    }

        public static string CtoF(double celsius)

        {

            double fahrenheit;

​

            if (celsius < -273.15)

            {

                return "Temperature below absolute zero!";

            }

​

            fahrenheit = celsius * 1.8 + 32;

            return "T = " + fahrenheit + " F";

        }

}