import java.util.ArrayList;
import java.util.List;
public class Main {
public static void main(String[] argv) throws Exception {
List list1 = new ArrayList();
List list2 = new ArrayList();
list1.addAll(list2);
list1.removeAll(list2);
list1.retainAll(list2);
list1.clear();
int newSize = 2;
list1.subList(newSize, list1.size()).clear();
}
}