單項選擇題

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

微信掃碼免費搜題