internal class Program
{
    static void Main(string[] args)
    {
        string stopWord = "exit";
        bool isWork = true;

        while (isWork)
        {
            Console.Write("еще не вышел? ");
            string userInput = Console.ReadLine();

            if (userInput == stopWord)
            {
                isWork = false;
            }
        }

        Console.WriteLine("Ура!");
        Console.ReadKey();
    }
}