Pasted

import java.io.File;
import java.util.HashSet;
import java.util.Scanner;
import java.io.FileNotFoundException;
 
public class ZadanieDwaPliki {
 
    public static void main(String[] args) throws FileNotFoundException {
        // TODO Auto-generated method stub
        Scanner skan1 = new Scanner(new File("plik1.txt"));
        Scanner skan2 = new Scanner(new File("plik2.txt"));
        HashSet<String> tab1 = new HashSet<String>();
        HashSet<String> tab2 = new HashSet<String>();
        while (skan1.hasNextLine()) {
            tab1.add(skan1.nextLine());
        }
        while (skan2.hasNextLine()) {
            tab2.add(skan2.nextLine());
        }
        HashSet<String> wspolne = new HashSet<String>(tab1);
        wspolne.retainAll(tab2);
        System.out.println("Wspólne " + wspolne);
        HashSet<String> roznica = new HashSet<String>(tab1);
        roznica.removeAll(tab2);
        System.out.println("Różnica " + roznica);
    }
}