試題詳解

1. public class TestString3{ 

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

 3. //insert code here 

5. System.out.println(s)； 

6. } 

7. } Which two code fragments, inserted independently at line 3, generate the output 4247? (choose two.)
(A) String s = "123456789"； s = (s - "123").replace(1, 3, "24") - "89"；
(B) StringBuffer s = new StringBuffer("123456789")； s.delete(0, 3).replace(1, 3, "24").delete(4, 6)；
(C) StringBuffer s = new StringBuffer("123456789")； s.substring(3, 6).delete(1, 3).insert(1, "24")；
(D) StringBuilder s = new StringBuilder("123456789")； s.substring(3, 6).delete(1, 2).insert(1, "24")；
(E) StringBuilder s = new StringBuilder("123456789")； s.delete(0, 3).delete(1, 3).delete(2, 5).insert(1, "24")；