using System;

public class Program

{

    public static void Main()

    {

        DateTime from = new DateTime(2020,05,20,18,30,00);

        DateTime to = new DateTime(2020,05,20,19,50,00);

        double a = (to - from).Hours;

        double b = (to - from).TotalHours;

        TimeSpan c = to - from;

        Console.WriteLine(a);

        Console.WriteLine(b);

        Console.WriteLine(c.Hours);

        Console.WriteLine(c.TotalHours);

                Console.WriteLine(Math.Round(c.TotalHours));

    }

}