using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine(PrepareSecretToCompare("NjYxZjEyNDRmNDE5MTYzNWFkNDMyZjRlNWIyZjU4YjBiNjhhNWNjMjgzYThlYzhjZjE1NjEwZTE4ZTVkMDJhYw=="));

    }

    public static string PrepareSecretToCompare(string secret)

    {

​

​

        byte[] secretBytes;

        try

        {

            secretBytes = Convert.FromBase64String(secret);

        }

        catch (FormatException)

        {

            return "Secret uses invalid hashing algorithm.";

        }

        if (secretBytes.Length == 32)

        {

            return secret + " (256)";

        }

        else if (secretBytes.Length == 64)

        {

            return secret + " (512)";

        }

        else

        {

            return "Secret uses invalid hashing algorithm.";

        }

    }   

}