using System;

using System.Text.RegularExpressions;

public class Program

{

    public static void Main()

    {

        //"

        string namePattern = @"^(?!.*([A-Za-z])\1\1)[A-Za-z]+$";

//- ? “ ” * _ & ! # $ % / ^ { } = | +

        string[] nameList = {

            "JEEFF",

            "JEFFF",

            "JEFF?",

            "JEFF\"",

            "JEFF*",

            "JEFF_",

            "JEFF&",

            "JEFF!",

            "JEFF#",

            "JEFF$",

            "JEFF/",

            "JEFF^",

            "JEFF{",

            "JEFF}",

            "JEFF=",

            "JEFF|",

            "JEFF+",

            "JEFFF",

             "JEF%?"

        };

​

        foreach (var name in nameList)

        {

            bool isValid = ValidateName(name, namePattern);

            Console.WriteLine($"{name}: {isValid}");

        }

    }

​

    static bool ValidateName(string name, string pattern)

    {

        Regex regex = new Regex(pattern);

        return regex.IsMatch(name);

    }

}