using System;

using System.Text;

using System.Security.Cryptography;

​

public class Program

{

    public static void Main()

    {

        /*Console.WriteLine("Enter Password");

        string pass=Console.ReadLine();

        Console.WriteLine("Enter Username");

        string username=Console.ReadLine();

        Console.WriteLine("Encrypt String");

        Console.WriteLine(EncryptPassword(pass,username.ToUpper()));

        */

        var now = DateTime.Now;

        var pastDate = now.AddDays(-21);

        Console.WriteLine(now.ToString());

        Console.WriteLine(pastDate.ToString());

        if(pastDate<now){

            Console.WriteLine("Date is passed");

        }

        else

        {Console.WriteLine("Date not passed");}

    }

     public static string EncryptPassword(string data, string salt)

     {

        if (salt != null)

        {

            salt = salt.ToLower();

            data += salt;

        }

        SHA256 hasher = SHA256.Create();

        byte[] hashedData = hasher.ComputeHash(Encoding.Unicode.GetBytes(data));

        StringBuilder sb = new StringBuilder(hashedData.Length * 2);

        foreach (byte b in hashedData)

        {

            sb.AppendFormat("{0:x2}", b);

        }

        return sb.ToString();

      }

}