using System;

public class Program

{

    public static void Main()

    {

        var start = DateTime.Parse("2021-11-20 00:00:00");

        var end = DateTime.Parse("2021-11-25 12:00:00");

        var days = (end - start).Days;

        var totalDays = (end - start).TotalDays;

        Console.WriteLine("days: " + days);

        Console.WriteLine("totalDays: " + totalDays);

​

    }

}