試題詳解

1. import java.util.*； 

2. public class Example{ 

3. public static void main(String[] args){ 

4. //insert code here 

5. set.add(new Integer(2))； 

6. set.add(new Integer(1)), 

7. System.out.println(set)； 

8. } 

9. } 

Which code, inserted at line 4, guarantees that this program will output [1, 2]?
(A) Set set = new TreeSet()；
(B) Set set = new HashSet()；
(C) Set set = new SortedSet()；
(D) List set = new SortedList()；
(E) Set set = new LinkedHashSet()；