import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.util.HashSet;
import java.util.Scanner;

public class Main {

    public static HashSet<Integer> ReadFromFileFirst() throws IOException {
        String fileName = "C:\\Users\\Asus\\Desktop\\Laba3_2.txt";
        FileInputStream file = new FileInputStream(fileName);
        HashSet<Integer> FirstSet = new HashSet<>();
        while (file.available()>0) {
            FirstSet.add(file.read());
        }
        System.out.println(FirstSet);
        file.close();
        return FirstSet;
    }

    public static HashSet<Integer> ReadFromFileSecond() throws IOException {
        String fileName = "C:\\Users\\Asus\\Desktop\\Laba3_2(X2).txt";
        FileInputStream file = new FileInputStream(fileName);
        HashSet<Integer> SecondSet = new HashSet<>();
        while (file.available()>0) {
            SecondSet.add(file.read());
        }
        System.out.println(SecondSet);
        file.close();
        return SecondSet;
    }

    public static HashSet UnionOfSets(HashSet<Integer> FirstSet, HashSet<Integer> SecondSet) {
        HashSet<Integer> Set = new HashSet<>();
        Set.addAll(FirstSet);
        Set.addAll(SecondSet);
        return Set;
    }

   public static HashSet<Integer> EvenElements(HashSet<Integer> Set){
        HashSet<Integer> EvenSet = new HashSet<>();
        for (int i = 0; i < 255 ; i++ );{
           Integer i = null;
           if ( Set.contains(i)){
               if(i % 2 == 0){
                   EvenSet.add(i);
               }
            }
       }
       return EvenSet;
   }

    public  static void SaveFile(HashSet<Integer> EvenSet) throws IOException {
        Scanner in = new Scanner(System.in);
        String outputFileName;
        System.out.println("Введите имя файла в который хотите вывести данные:");
        outputFileName = in.nextLine();
        FileWriter out = new FileWriter(outputFileName);
        out.write("\n  " + EvenSet);
        out.close();
    }


    public static void main(String[] args) throws IOException {
        HashSet<Integer> FirstSet = ReadFromFileFirst();
        HashSet<Integer> SecondSet = ReadFromFileSecond();
        HashSet<Integer> Set = UnionOfSets( FirstSet , SecondSet);
        HashSet<Integer> EvenSet = EvenElements(Set);
        SaveFile(EvenSet);
    }
}