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

namespace ConsoleApp4
{
    class Program
    {
        public static void Metod(string text)
        {

            int a = text.Length;
            string Ntext = text.Substring(a / 2, a / 2);
            Ntext = Ntext.Replace(" ", string.Empty);
            Console.WriteLine(Ntext);
        }



        public static void Main(string[] args)
        {
            string text;
            text = Console.ReadLine();
            Metod(text);
            Console.ReadKey();
        }
    }
}