import java.util.*;
import java.util.stream.*;
class Main {
public static void main(String[] args) {
List<Integer> list = Arrays.asList(-1,0,1,2,3);
System.out.println(list);
System.out.println(list.stream().filter(i->i>0).collect(Collectors.toList()));
System.out.println(list.stream().filter(i->i>0).collect(Collectors.toList()).add(1));
System.out.println(list);
List<Integer> a = list.stream().filter(i->i>0).collect(Collectors.toList());
a.add(1);
System.out.println(a);
System.out.println(list);
}
}
