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。
(提示:此任务可以分为三个子任务分成若干步骤进行。先声明基类,再声明派生类,逐级进行,分步调试。——这种方法适用于做任何的项目)
#include<iostream> #include<Cmath> using namespace std; class Point //定义坐标点类 {public: double x,y; //点的横坐标和纵坐标 Point(){x=0;y=0;} Point(double x0,double y0) {x=x0; y=y0;} void getX(){cout<<"输入圆的圆心";cin>>x;} //建立输入横坐标x的函数 void getY(){cin>>y;} //建立输入纵坐标y的函数 void PrintP(){cout<<"Point:("<<x<<","<<y<<")";} //friend ostream &operator <<(ostream &output,Point &p); //定义<<的重载 }; class Circle: public Point { protected : double ride; Circle(){x=0;y=0;ride=0;} Circle(double x0,double y0,double r):Point(x0,y0) { ride = r; } public: double getride(){cout<<"输入圆的半径";cin>>ride;return ride; } void Printr(){cout<<"输出圆的半径";cout<<ride;} double area(); //定义计算圆面积的函数 }; class Cylinder:public Circle { protected : double height; public: Cylinder(){double x=0;double y=0;double ride=0;double hejght=0;} Cylinder(double x0,double y0,double r,double h):Circle(x0,y0,r),height(h){} double getheight(){cout<<"输入圆柱的高";cin>>height;return height;} double cirarea(); //计算圆柱的表面积 double volunme(); //计算圆柱的体积 friend ostream &operator <<(ostream &output,Cylinder &p); //定义<<的重载 }; ostream &operator <<(ostream &output,Cylinder &p) { output<<"("<<p.x<<","<<p.y<<")"<<"半径"<<p.ride<<"高"<<p.height<<endl; return output; } double Circle::area() { return 3.14*ride*ride; } double Cylinder::cirarea() { cout<<"圆柱的表面积为"; return 3.14*ride*2*height; } double Cylinder::volunme() { cout<<"圆柱的体积为"; double V; V = area()*height; return V; } int main() { cout<<"其实最初的圆柱"; Cylinder C1(0,0,1,1),C2; C1.PrintP(); cout<<endl; C1.Printr(); cout<<endl; cout<<"圆的面积为"; cout<<C1.area ()<<endl; cout<<C1.cirarea()<<endl; cout<<C1.volunme()<<endl; cout<<"新的圆柱"<<endl; C2.getX(); C2.getY(); C2.getride(); C2.getheight(); C2.PrintP(); cout<<endl; C2.Printr(); cout<<endl; cout<<"圆的面积为"; cout<<C2.area ()<<endl; cout<<C2.cirarea()<<endl; cout<<C2.volunme()<<endl; cout<<"圆柱的信息:"; cout<<C2; system("pause"); return 0; }