1.
已知如下代码:
1: class Example {
2: String str;
3: public Example( ){
4: str= "example";
5: }
6: public Example(String s){
7: str=s;
8: }
9: }
10: class Demo extends Example{
11: }
12: public class Test {
13: public void f ( ) {
14: Example ex = new Example("Good");
15: Demo d = new Demo("Good");
16: }}
哪句语句会导致错误?