3a行
3b行
3a行或3b行
既非3a,也非3b
第1题:
( 12 )有如下程序:
#include <iostream>
using 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 {return "Dog" ; }
char* getVoice ( ) const {return "Woof"}
};
void type ( Animal& a ) {cout<<a.getType ( ) ; }
void speak ( Animal a ) {cout<<a.getVoice ( ) ; }
int main ( ) {
Dog d; type ( d ) ; cout<<" speak" ; speak ( d ) ; cout<<endi;
return 0;
}
运行时的输出结果是【 12 】 。
第2题:
classAnimal{AnimalgetOne(){returnnewAnimal();}}classDogextendsAnimal{//insertcodehere}classAnimalTest{publicstaticvoidmain(String[]args){Animal[]animal={newAnimal(),newDog()};for(Animala:animal){Animalx=a.getOne();}}}和代码:3a.DoggetOne(){returnnewDog();}3b.AnimalgetOne(){returnnewDog();}第3行中插入的哪项编译且运行无异常?
A.3a行或3b行
B.既非3a,也非3b
C.3a行
D.3b行
第3题:
有如下程序:
nclude<iostream>
using 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(Animal&A){cout<<a.getType();}
void speak(AnimalA){cout<<a.getVoice();}
int main(){
Dog d.type(D);tout<<“speak”;speak(D);cout<<endl;
return 0;
}
运行时的输出结果是【 】
第4题:
第5题:
第6题:
interface Animal { void soundOff(); } class Elephant implements Animal { public void soundOff() { System.out.println(“Trumpet”); } } class Lion implements Animal { public void soundOff() { System.out.println(“Roar”); } } class Alpha1 { static Animal get( String choice ) { if ( choice.equalsIgnoreCase( “meat eater” )) { return new Lion(); } else { return new Elephant(); } } } Which compiles?()
第7题:
11. class Animal { public String noise() { return “peep”; } } 12. class Dog extends Animal { 13. public String noise() { return “bark”; } 14. } 15. class Cat extends Animal { 16. public String noise() { return “meow”; } 17. } ..... 30. Animal animal = new Dog(); 31. Cat cat = (Cat)animal; 32. System.out.printIn(cat.noise()); What is the result?()
第8题:
0
1
2
3
3.3333
第9题:
Cat is-a Animal
Cat is-a Jumper
Dog is-a Animal
Dog is-a Jumper
Cat has-a Animal
Beagle has-a Tail
Beagle has-a Jumper
第10题:
0
1
2
3
第11题:
0
1
2
3
第12题:
3a行或3b行
既非3a,也非3b
3a行
3b行
第13题:
It can be inferred from the passage that all of the following are ways of producing new strains of influenza viruses EXCEPT______.
A. two influenza viruses in the same animal recombining
B. animal viruses recombining with human viruses
C. two animal viruses recombining in one animal
D. two animal viruses recombining in a human
第14题:
1.classAnimal{AnimalgetOne(){returnnewAnimal();}}2.classDogextendsAnimal{3.//insertcodehere4.}5.6.classAnimalTest{7.publicstaticvoidmain(String[]args){8.Animal[]animal={newAnimal(),newDog()};9.for(Animala:animal){10.Animalx=a.getOne();11.}12.}13.}和代码:3a.DoggetOne(){returnnewDog();}3b.AnimalgetOne(){returnnewDog();}第3行中插入的哪项将编译且运行无异常?()
A.3a行
B.3b行
C.3a行或3b行
D.既非3a,也非3b
第15题:
下列程序片段中,能通过编译的是( )。
A.public abstract class Animal{ public void speak;}
B.public abstract class Animal{ public void speak{);}
C.public class Animal{ pubilc abstract void speak;}
D.public abstract class Animal{ pubile abstract void speak{};}
第16题:
第17题:
classCatextendsAnimal{}对于下述代码说法正确的是()
第18题:
Clone animal:克隆动物
第19题:
peep
bark
meow
Compilation fails.
An exception is thrown at runtime.
第20题:
0
1
2
3
第21题:
new Animal().soundOff();
Elephant e = new Alpha1();
Lion 1 = Alpha.get(“meat eater”);
new Alpha1().get(“veggie”).soundOff();
第22题:
1
2
3
4
第23题: