多选题 Given:
3. public class RediMix extends Concrete {
4. RediMix() {System.out.println("r "); }
5. public static void main(String[] args) {
6. new RediMix();
7. }
8. }
9. class Concrete extends Sand {
10. Concrete() {System.out.print("c ");
11. private Concrete(String s) { }
12. }
13. abstract class Sand {
14. Sand() {System.out.print("s "); }
15. }
What is the result?