1.class SuperFo{
2. SuperFo doStuff(int x){
3.return new SuperFo()
4.}
5.}
6.
7.class Foo extends SuperFo{
8.//insert code here
9.}
和四個聲明:
Foo doStuff(int x){return new Foo();}
Foo doStuff(int x){return new SuperFoo();}
SuperFoo doStuff(int x){return new foo();}
SuperFoo doStuff(int y){return new SuperFoo();}
分別插入到第8行,有幾個可以通過編譯 ()
A.1
B.2
C.3
D.4
E.5