C++實驗19

一、座標到圓到圓柱

#include<iostream>
using namespace std;
#define pi 3.1415926

class point
{
    float x;
    float y;
public:
    point(int a=0, int b=0) {x=a;y=b;cout<<"point constructor\n";}
    ~point()           {cout<<"point destructor\n";}
    void display_point()
    {
        cout<<"x="<<x<<"\ty="<<y<<endl;
    }
};
class circle:public point
{
    float r;
public:
    circle(float a=0,float b=0,float c=0):point(a,b)
    {
        r=c;
        cout<<"circle constructor"<<endl;
    }
    ~circle(){cout<<"circle destructor"<<endl;}
    float getr(){return r;}
    float area();
    void display_circle();
};
float circle::area() {return r*r*pi;}
void circle::display_circle() 
{
    display_point();
    cout<<"r="<<r<<endl;
}

class cylinder:public circle
{
    float hight;
public:
    cylinder(float a=0, float b=0,float c=0, float d=0):circle(a,b,c)
    {
        hight=d;
        cout<<"cylinder consturctor"<<endl;
    }
    ~cylinder(){cout<<"cylinder destructor"<<endl;}
    float volume() {return area()*hight;}
    void display()
    {
        display_circle();
        cout<<"hight="<<hight<<endl;
    }
};
void main()
{
    cylinder a(1,2,3,4);
    a.display();
}

二、學生類派生

#include<iostream>
#include<string.h>

class student
{
    int id;
    char name[20];
    char sex[6];
    int age;
public:
    student(int a,char *b, char *c, int d)
    {
        id=a;strcpy(name,b);strcpy(sex,c);age=d;
        std::cout<<"student constructor\n";
    }
    ~student(){std::cout<<"student destructor\n";}
    void print_student();
};
class phd: public student
{
    int papernum;
    float workhour;
public:
    phd(int a, char *b, char *c, int d,int e, float f):student(a,b,c,d)
    {
        papernum=e;
        workhour=f;
        std::cout<<"phd constructor\n";
    }
    ~phd(){std::cout<<"phd destructor\n";}
    void print_phd();
};
class master: public student
{
    float grade;
    int flag;
public:
    master(int a, char *b, char *c, int d, float e, int f):student(a,b,c,d)
    {
        grade=e;
        flag=f;
        std::cout<<"master constructor\n";
    }
    ~master(){std::cout<<"master destructor\n";}
    void print_master();
};
class undergraduate: public student
{
    float gradein;
    float gradeout;
public:
    undergraduate(int a, char *b, char *c, int d, float e, float f):student(a,b,c,d)
    {
        gradein=e;
        gradeout=f;
        std::cout<<"undergraduate destructor\n";
    }
    ~undergraduate(){std::cout<<"undergraduate destructor\n";}
    void print_undergraduate();
};
void student::print_student()
{
    std::cout<<"idnumber: "<<id<<"\nname: "<<name<<"\nsex: "<<sex<<"\nage: "<<age<<'\n';
}
void phd::print_phd()
{
    print_student();
    std::cout<<"paper number: "<<papernum<<"\nworking hours: "<<workhour<<'\n';
}
void master::print_master()
{
    print_student();
    std::cout<<"grade: "<<grade<<"\nattending? ";
    if(flag)
        std::cout<<"yes\n";
    else
        std::cout<<"no\n";
}
void undergraduate::print_undergraduate()
{
    print_student();
    std::cout<<"incourse grade: "<<gradein<<"\noutcourse grade: "<<gradeout<<'\n';
}
void main()
{
    phd a(12345678,"張三","男",25,3,20);
    master b(2234567,"李四","女",24,98,0);
    undergraduate c(32345678,"趙五","男",23,100,100);
    a.print_phd();
    std::cout<<'\n';
    b.print_master();
    std::cout<<'\n';
    c.print_undergraduate();
}