well

var input = "";
            StringBuilder sb = new StringBuilder();
            var typeOfBlackBOXint = typeof(BlackBoxInt);
            var blackBox = (BlackBoxInt)Activator.CreateInstance(typeOfBlackBOXint, true);
            var methods = typeOfBlackBOXint.GetMethods(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Static);
            var fields = typeOfBlackBOXint.GetFields(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public);
            int result = 0;

            while ((input = Console.ReadLine()) != "END")
            {
                var tokens = input.Split(new char[] { '_' }, StringSplitOptions.RemoveEmptyEntries);
                int param = int.Parse(tokens[1]);
                string name = tokens[0];
                methods.First(m => m.Name == name).Invoke(blackBox, new object[] { param });
                foreach (var field in fields)
                {
                    sb.AppendLine(field.GetValue(blackBox).ToString());
                }
            }