C++程序设计（10.3）

/*

*实验内容:   

* 程序的版权和版本声明部分   

* Copyright (c) 2011, 烟台大学计算机学院学生   
* All rights reserved.   

* 文件名称：基类，派生    
* 作 者： 杨坛坛   

* 完成日期： 2012 年 4 月 25日   
* 版 本号： vc2008 

*问题描述：（1）先建立一个Point(点)类，包含数据成员x,y(坐标点)；

（2）以Point为基类，派生出一个Circle(圆)类，增加数据成员 (半径)；

（3）再以Circle类为直接基类，派生出一个Cylinder(圆柱体)类，再增加数据成员h(高)。

要求编写程序，设计出各类中基本的成员函数（包括构造函数、析构函数、修改数据成员和获取数据成员的公共接口、用于输出的重载运算符“<<”函数等），

使之能用于处理以上类对象，最后求出圆柱体的表面积、体积并输出。

*/

#include <iostream>

#include<Cmath>

#include<iomanip>

using namespace std;

const double PI = 3.141592653;

class Point//点类声明
{
public:
Point(){x = 0;y = 0;}
Point(double x0,double y0):x(x0),y(y0){ }
~Point(){ }
double getx(){return x;}
double gety(){return y;}
friend ostream &operator << (ostream & input, Point & c);
protected:
double x, y;   //点的横坐标和纵坐标
};
ostream &operator << (ostream & input, Point & c)
{
input << "点:(" << c.x << "," << c.y << ")";

return input;
}
class Circle: public Point   //以点类为基类的派生类
{
public:
Circle(){radius = 0;}
Circle(double x0, double y0, double r):Point(x0, y0),radius(r){ }      //构造函数
~Circle(){}
double getr(){return radius;}
double area1();
friend ostream &operator << (ostream & out, Circle & c);
protected:
double radius;
};
double Circle::area1() //圆形面积
{
double c_area = PI * getr() * getr();

return c_area;
}
ostream &operator << (ostream & out, Circle & c)
{
out << "(" << c.getx() << "," << c.gety() << ")" << "为圆心" << c.radius << "为半径的圆";

return out;
}

class Cylinder: public Circle  //以圆类为基类的派生类
{
public:
Cylinder(){height = 0;}
Cylinder(double x1,double y1, double r1, double h):Circle(x1, y1, r1), height(h){ }
~Cylinder(){}
double geth(){return height;}
double area2();
double volume();
friend ostream &operator << (ostream & out, Cylinder & c);
private:
double height;
};

double Cylinder::area2()
{

//double c_area = PI * getr() * getr();

double c_cir = 2 * PI * getr() * height;   //圆柱侧面积

return (c_cir + 2 * area1());
}

double Cylinder::volume()
{
return (PI * getr() * getr() * height);
}

ostream &operator << (ostream & out, Cylinder & c)
{
out << "(" << c.getx() << "," << c.gety() << ")" << "为圆心" << c.radius << "为半径" << c.height << "为高的圆柱体";

return out;
}

int main()
{
Cylinder cy(2, 2, 1, 3);

cout << cy << endl;

cout << setiosflags(ios::fixed) << setprecision(2);

cout << "表面积是：" << cy.area2() << endl;

cout << "体积是：" << cy.volume() << endl;

system("pause");

return 0;
}

 

运行结果：
(2,2)为圆心1为半径3为高的圆柱体

表面积是：25.13

体积是：9.42

请按任意键继续. . .