package eecs1022;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Scanner;

public class Duplicates 
{
    public static void main(String[] args) throws FileNotFoundException 
    {
	String name = "Lab1.ePost";
	File file = new File(name);
	Scanner input = new Scanner(file);
	List<String> entries = new ArrayList<String>();
	while (input.hasNextLine())
	{
	    String line = input.nextLine();
	    String[] part = line.split("\\s+");
	    String ppy = part[0];
	    entries.add(ppy);
	}
	input.close();
	
	Collections.sort(entries);
	
	for (int i = 0; i < entries.size() - 1; i++)
	{
	    String current = entries.get(i);
	    String next = entries.get(i + 1);
	    if (current.equals(next))
	    {
		System.out.println(current);
	    }
	}
    }
}