C实验报告-实验5多态性与虚函数

1、实验5 多态性与虚函数一、实验目的和要求了解静态联编和动态联编的概念。掌握动态联编的条件。二、实验内容和原理事先编写好程序，上机调试和运行程序，分析结果。（1）实验指导书P96 14任选一题。（2）实验指导书P100 56任选一题。三、实验环境联想计算机，Windows XP操作系统，Visual C+ 6.0四、算法描述及实验步骤（1）编写源程序。（2）检查程序有无错误(包括语法错误和逻辑错误)，有则改之。（3）编译和连接，仔细分析编译信息，如有错误应找出原因并改正之。（4）运行程序，分析结果。（5）将调试好的程序保存在自己的用户目录中，文件名自定。五、调试过程12六、实验结果15七、总结动

2、态联编需要满足3个条件，首先类之间满足类型兼容规则；第二是要声明虚函数；第三是要由成员函数来调用或者是通过基类指针、引用来访问虚函数。附录：1 public:virtual void f(float x)coutBase:f(float)xendl;void g(float x)coutBase:g(float)xendl;void h(float x )coutBase:h(float)xendl;class Derived:public Basepublic:virtual void f(float x)coutDerived:h(float)xf(3.14f);pb-f(3.14f);p

3、b-g(3.14f);pb-h(3.14f);pb-h(3.14f);return 0;2#includeusing namespace std;#includeclass Teacherpublic:Teacher(string n,int h);virtual double salary()=0;virtual void print()=0;protected:string name;int lessons;Teacher:Teacher(string n,int h)name=n;lessons=h;class Professor:public Teacherpublic:Profess

4、or(string n,int h):Teacher(n,h)double salary()return 5000 + 50 * lessons;void print();void Professor:print()coutnametProfessorttlessonslessons;couttearned ￥salary()endl; class Associateprofessor:public Teacherpublic:Associateprofessor(string n,int h):Teacher(n,h)double salary()return 3000+30*lessons

5、;void print();void Associateprofessor:print()coutna#includeusing namespace std;#includeclass Teacherpublic:Teacher(string n,int h);virtual double salary()=0;virtual void print()=0;protected:string name;int lessons;Teacher:Teacher(string n,int h)name=n;lessons=h;class Professor:public Teacherpublic:P

6、rofessor(string n,int h):Teacher(n,h)double salary()return 5000 + 50 * lessons;void print();void Professor:print()coutnametProfessorttlessonslessons;couttearned ￥salary()endl; class Associateprofessor:public Teacherpublic:Associateprofessor(string n,int h):Teacher(n,h)double salary()return 3000+30*l

7、essons;void print();void Ass metAssociateprofessortlessonslessons;couttearned ￥salary()endl;class Lecturer:public Teacherpublic:Lecturer(string n,int h):Teacher(n,h)double salary()return 2000+20*lessons;void print();void Lecturer:print()coutnametLecturerttlessonslessons;couttearned ￥salary()endl;int main()Teacher * t3;t0=new Professor(Tang XiHua,1