基类与派生

#include <iostream>
#include <cstring>

using namespace std;
class Teacher
{
public:
    Teacher(int ,char[],char);
    void display();
private:
    int num;
    char name[20];
    char sex;
};
Teacher::Teacher(int n,char nam[],char s)
{
    num=n;
    strcpy(name,nam);sex=s;
}
void Teacher::display()
{
    cout<<num<<endl;
    cout<<name<<endl;
    cout<<sex<<endl;
}
class BirthDate
{
public:
    BirthDate(int ,int ,int );
    void display();
    void change(int ,int ,int );
private:
    int year;
    int month;
    int day;
};
BirthDate::BirthDate(int y,int m,int d)
{
    year=y;
    month=m;
    day=d;
}
void BirthDate::display()
{
    cout<<month<<" "<<day<<" "<<year<<endl;
}
void BirthDate::change(int y,int m,int d)
{
    year=y;
    month=m;
    day=d;
}
class Professor:public Teacher
{
public:
    Professor(int,char[],char,int,int,int,float);
    void display();
    void change(int ,int ,int);
private:
    float area;
    BirthDate birthday;
};
Professor::Professor(int n,char nam[20],char s,int y,int m,int d,float a):
    Teacher(n,nam,s),birthday(y,m,d),area(a){}
    void Professor::display()
    {
        Teacher::display();
        birthday.display();
        cout<<area<<endl;
    }
    void Professor::change(int y,int m,int d)
    {
        birthday.change(y,m,d);
    }
int main()
{
    Professor prof1(2012,"Zhang",'f',1993,10,0,125.4);
    cout<<endl;
    prof1.display();
    cout<<endl;
    prof1.change(1950,6,1);
    prof1.display();


    return 0;
}