namespace ConsoleApp9
{
    internal class Program
    {
        static void Main(string[] args)
        {
            String? name = null;
            while (name == null)
            {
                String preName = Console.ReadLine();
                if (preName.Length > 3)
                {
                    name = preName;
                }
            }
            Console.WriteLine(name);
        }
      
 
    }
}