//package profesjonal; Bartlomiej Wiewiora

import java.io.*;
import java.util.*;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;


public class Profesjonal {


    public static void main(String[] args) {
        File fileDir = new File("opis.txt");

        try{
        BufferedReader in = new BufferedReader(
           new InputStreamReader(
                      new FileInputStream(fileDir), "UTF8"));

        String str;
        int maxLength = 0;

                String najdl = "";
            while ((str = in.readLine()) != null) {
                String [] tab = str.split("[ .,\\-]");

                    for(int d = 0; d < tab.length; d++){
                             if (tab[d].length() > maxLength) {
                            maxLength = tab[d].length();
                            najdl = tab[d];
          }
                        }


                }

                System.out.println(najdl);

                in.close();
        }

        catch (UnsupportedEncodingException e)
        {
            System.out.println(e.getMessage());
        }
        catch (IOException e)
        {
            System.out.println(e.getMessage());
        }
        catch (Exception e)
        {
            System.out.println(e.getMessage());
        }
    }

}


////////////


//package kolos2; Bartlomiej Wiewiora

import java.io.*;
import java.util.*;



public class Kolos2
{

    public static void main(String[] args) throws IOException
    {
        ArrayList<Integer> liczby = new ArrayList<Integer>();
        Scanner patrz = new Scanner(System.in);

        String nr = patrz.nextLine();
        String[] tab = nr.split("[ ]");

        for(int i = 0; i<tab.length; i++){
            liczby.add(Integer.parseInt(tab[i]));
        }

        Collections.sort(liczby);

        int siz = liczby.size();

        int od = siz-1;

        int dz = od/2;

        int med = liczby.indexOf(liczby.get(dz));

        System.out.println(liczby.get(med));
    }

}