using System;

using System.Text.RegularExpressions;

public class Program

{

     public static bool Base64Encode(string plainText) {

            Regex regex = new Regex(@"((?=.*\d)(?=.*[A-Z]).{8,50})");

            Match match = regex.Match(plainText);

            return match.Success;

}

    public static void Main()

    {

        Console.WriteLine(Base64Encode("somethinG4"));

    }

}