using System;

namespace ValidUsername
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] usernames = Console.ReadLine().Split(", ");

            for (int i = 0; i < usernames.Length; i++)
            {
                bool isValidLegnth = false;
                bool isValidContent = false;
                string currentUsername = usernames[i];
                if (currentUsername.Length >= 3 && currentUsername.Length <= 16)
                {
                    isValidLegnth = true;

                }
                for (int j = 0; j < currentUsername.Length; j++)
                {
                    char currentSymbol = currentUsername[j];
                    if (char.IsLetterOrDigit(currentSymbol) || currentSymbol == '-' || currentSymbol == '_')
                    {
                        isValidContent = true;

                    }
                    else
                    {
                        isValidContent = false;
                    }
                }
                if (isValidContent && isValidLegnth)
                {
                    Console.WriteLine(currentUsername);
                }
            }

        }
    }
}