华为C++笔试题--经典版本

脚本执行失败问题1. 虚函数是可以内联的，这样就可以减少函数调用的开销，提高效率（错误）2. 一个类里可以同时存在参数和函数名都相同的虚函数与静态函数（错误）3. 父类的析构函数是非虚的，但是子类的析构函数是虚的，delete子类指针(指向该子类对象)，会调用父类的析构函数（正确）//任何情况下删除子类都会调用到父类的析构函数4．对于下面的类CA，sizeof(CA) = _B_：A. 4B. 8C. 12D. 16class CA{public:CA();virtual ~CA(); //因为有虚函数，所以会有4个字节的虚表指针private:int m_iTime; //成员变量4个字节public:int GetTime();int SetTime(int iTime);};5．下面这段程序，打印结果是_A_：A. 1B. 2C. 3D. 以上都不对int g_iCount = 0;class CParent{public:CParent() {}~CParent() {g_iCount += 1;}};class CSon : public CParent{public:CSon() {}~CSon() {g_iCount += 2;}};main(){CParent* p = new CSon();delete p;std::cout << g_iCount << std::endl;}6．请问下面这段程序的输出结果是_A_：A. 2,1,B. 2,2,C. 1,1,D. 1,2,class CParent{public:CParent() {}virtual ~CParent() {}public:virtual void Print(){ std::cout << "1,"; };};class CSon : public CParent{public:CSon() {};virtual ~CSon() {};public:void Print(){ std::cout << "2,"; };};void Test1(CParent& oParent){oParent.Print();}void Test2(CParent oParent){oParent.Print();}main(){CSon * p = new CSon();Test1(*p); //这里只是一个引用Test2(*p); //这里会在栈空间重新构造Cparent类对象 delete p;}7．请问下面这段程序的输出结果是_D_：A. 2,1,B. 2,2,C. 1,1,D. 1,2,class CParent{public:CParent() {}virtual ~CParent() {}public:void Print(){ std::cout << "1," ; };};class CSon : public CParent{public:CSon() {}virtual ~CSon() {}public:void Print(){ std::cout << "2,"; };};main(){CSon oSon;CParent * pParent = &oSon;CSon * pSon = &oSon;pParent->Print();pSon->Print();}8．请问下面这段程序的输出结果是_C_：A. 2,1,B. 2,2,C. 1,2,D. 1,1,class CParent{public:CParent() {Print();}virtual ~CParent() {}public:virtual void Print(){ std::cout << "1,"; } };class CSon : public CParent{public:CSon() {Print();}virtual ~CSon() {}public:void Print(){ std::cout << "2,"; }};main(){CParent * pParent = new CSon();delete pParent;}9．请问下面这段程序的输出结果是_D_：A. 2,2,B. 2,C. 输出结果不确定D. 以上都不对class CParent{public:CParent() {Print();}virtual ~CParent() {}public:virtual void Print() = 0;};class CSon : public CParent{public:CSon() {Print();}virtual ~CSon() {}public:void Print(){ std::cout << "2,"; };};main(){CParent * pParent = new CSon();delete pParent;}10．请仔细阅读以下程序：class Base{public:virtual bool operator == (int iValue){std::cout << "I am Base class !" << std::endl;return true;}virtual ~Base(){}};class Derive: public Base{public:virtual bool operator == (int iValue){std::cout << "I am Derive class !" << std::endl;return true;}virtual ~Derive(){}};int main(){Derive derive;Base* pBase = &derive;Derive* pDerive = &derive;*pBase == 0;*pDerive == 0;return 0;}程序的输出结果是_B_：A、I am Base class !I am base class !B、I am Derive class !I am Derive class !C、I am base class !I am Derive class !D、I am Derive class !I am Base class !11．请仔细阅读以下程序：class Base{public:virtual void display(std::string strShow = "I am Base class !") { std::cout << strShow << std::endl; }virtual ~Base(){}};class Derive: public Base{public:virtual void display(std::string strShow = "I am Derive class !") { std::cout << strShow << std::endl; }virtual ~Derive(){}};int main(){Base* pBase = new Derive();Derive* pDerive = new Derive();pBase->display();pDerive->display();delete pBase;delete pDerive;return 0;}程序的输出结果是_C_：A、I am Base class !I am base class !B、I am Derive class !I am Derive class !C、I am base class !I am Derive class !D、I am Derive class !I am Base class !12．请仔细阅读以下程序：class Base{public:virtual void display() const{ std::cout << "I am Base class !" << std::endl; } virtual ~Base(){}};class Derive: public Base{public:virtual void display(){ std::cout << "I am Derive class !"<< std::endl; } virtual ~Derive(){}};int main(){Base* pBase = new Derive();Derive* pDerive = new Derive();pBase->display();pDerive->display();delete pBase;delete pDerive;return 0;}程序的输出结果是_C_：A、I am Base class !I am base class !B、I am Derive class !I am Derive class !C、I am base class !I am Derive class !D、I am Derive class !I am Base class !13．在C++中，多态性存在于_B_：A、同一个类的多个同名函数之间B、子类继承层次中C、父类的多个同名函数之间D、以上都不是14．下面黑体加粗的语句存在问题，请问下面的修改哪个是正确的？Bclass A{public:void Func();..};class B{private:bool Func() const;..};class C:public A,public B{...}; // class definition is unimportantC test;test.Func(); //look hereA．test.B::Func(); B．test.A::Func();C．B::test.Func(); D．A::test.Func();15．判断：子类可以访问父类保护成员，子类的友元类也可以通过子类对象去访问父类的保护成员。