11.classAnimal{publicStringnoise(){returnpeep”;}}12.classDogextendsAnimal{13.publicStringnoise(){returnbark”;}14.}15.classCatextendsAnimal{16.publicStringnoise(){returnmeow”;}17.}.....30.Animalanimal=newDog();31.Catcat=(Cat)animal;32.System.out.printIn(cat.noise());Whatistheresult?()A.peepB.barkC.meowD.Compilationfails.E.Anexceptionisthrownatruntime.

11.classAnimal{publicStringnoise(){returnpeep”;}}12.classDogextendsAnimal{13.publicStringnoise(){returnbark”;}14.}15.classCatextendsAnimal{16.publicStringnoise(){returnmeow”;}17.}.....30.Animalanimal=newDog();31.Catcat=(Cat)animal;32.System.out.printIn(cat.noise());Whatistheresult?()

A.peep

B.bark

C.meow

D.Compilationfails.

E.Anexceptionisthrownatruntime.


相关考题:

有如下程序: include using namespaee std;class Animal{ public: virtual char*g 有如下程序:include<iostream>using namespaee std;c lass Animal{public:virtual char*getType( )const{return"Animal";}virtual char*getVoice( )const{return"Voice";}};class Dog:public Animal{public:char*getType( )const{return"Dog";}char*getVoice( )eonst{return"Woof";}};void type(AnimalA) {cout<<a.getType( );}void speak(Animal A) {eout<<a.getVoice( );}int main( ){Dog d;type(D) ;cout<<"speak";speak(D) ;cout return 0;}程序的输出结果是______。

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有如下程序:ncludeiostreamusing namespace std;class Animal{public:virtual char*getType()const{return“Animal”;}virtual char*getVoice()const{return“Voice”;}};class Dog:public Animal{public:char*getType()const{rgturn“Dog”;}char*getVoice()const{retum“Woof”;}};void type(AnimalA){couta.getType();}void speak(AnimalA){couta.getVoice();}int main(){Dog d.type(D);tout“speak”;speak(D);coutendl;return 0;}运行时的输出结果是【 】

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