第十周实验报告3

（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，最后求出圆格柱体的表面积、体积并输出。

#include<iostream>#define pi 3.1415using namespace std;class Point{public:int x;int y;//public:Point (int xx = 0, int yy = 0):x(xx), y(yy){};~Point();void setPoint(int a, int b);friend ostream & operator << (ostream & out, Point &a);};Point::~Point (){}ostream & operator << (ostream & out, Point & a){out << "(" << a.x << "," << a.y << ")" << endl;return out;}void Point::setPoint (int a, int b){x = a;y = b;}class Circle: public Point {public:int r;public:Circle (int xx, int yy, int r1):Point (xx, yy){r = r1;}~Circle();void setCircle(int a, int b, int c);friend ostream & operator << (ostream & out, Circle & a);};Circle::~Circle(){}void Circle::setCircle(int a, int b, int c){x = a;y = b;r = c;}ostream & operator << (ostream & out, Circle & a){out << "圆心："<< "(" << a.x << "," << a.y << ")" << endl;out << "半径：" << a.r;return out;}class Cylinder: public Circle{private:int h;public:Cylinder(int xx, int yy, int r1, int h1):Circle(xx, yy, r1){h = h1;}~Cylinder();void setCylinder(int a, int b, int c, int d);friend ostream & operator << (ostream &out, Cylinder &a);double Carea();double Cvolume();};Cylinder::~Cylinder(){}void Cylinder::setCylinder(int a, int b, int c, int d){x = a;y = b;r = c;h = d;}ostream & operator << (ostream &out, Cylinder &a){out <<"圆心:" << "("<< a.x <<"," <<a.y <<")" << endl;out<<"半径:" << a.r << endl;out<< "高: " << a.h << endl;return out;}double Cylinder::Carea(){double m;m = 2 * r * pi;return (m * h);}double Cylinder::Cvolume(){return (r * r * pi * h);}int main(){Cylinder c(2, 2, 2 ,2);cout << c;cout<< "表面积:" << c.Carea () << endl;cout << "体积：" << c.Cvolume () << endl;system("pause");return 0;}

没有基类的许可，子类是不可以使用基类的数据的，保护自己的隐私！