using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Regular_Expressions
{
    public class Program
    {
        public static void Main(string[] args)
        {
            Print01ValidUsernames();
        }

        private static void Print01ValidUsernames()
        {

            var stringText = Console.ReadLine().Split(new string[] { ", "}, StringSplitOptions.RemoveEmptyEntries) ;
            var final = new List<string>();
            foreach (var item in stringText)
            {
                if (item.Count()>=3 &item.Count()<=16)
                {
                    foreach (var kvp in item)
                    {
                        if ( char.IsLetter(kvp)|| kvp =='-' || kvp =='_' ||char.IsDigit(kvp))
                        {
                            final.Add(item);
                        }
                        else
                        {
                            final.Remove(item);
                            break;
                        }
                    }

                }
            }
            foreach (var item in final.Distinct())
            {
                Console.WriteLine(item);
            }

        }
    }
}