import java.util.Comparator;
import java.util.TreeSet;
// A reverse comparator for strings.
class MyComp implements Comparator {
public int compare(String a, String b) {
return b.compareTo(a);
}
}
class CompDemo {
public static void main(String args[]) {
TreeSet ts = new TreeSet(new MyComp());
ts.add("C");
ts.add("A");
ts.add("B");
ts.add("E");
ts.add("F");
ts.add("D");
for (String element : ts)
System.out.print(element + " ");
}
}