第10周实验报告任务3

/* (程序头部注释开始)  * 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：点、圆、圆柱 * 作 者： 郭岩岩 * 完成日期：2012 年4月 24日 * 版 本 号： vc.1 * 对任务及求解方法的描述部分 * 输入描述：  * 问题描述：  * 程序输出：  *程序头部的注释结束 */#include<iostream>using namespace std;class Point //定义坐标点类{public:Point(double a=0,double b=0);void setpoint(double c,double d);double getx(){return x;}double gety(){return y;}friend ostream &operator<<(ostream &output,Point &p);protected:double x,y;};Point::Point (double a,double b){x=a;y=b;}void Point::setpoint(double c,double d){x=c;y=d;}ostream& operator<<(ostream &output,Point &p){output<<"("<<p.x <<","<<p.y<<")"<<endl;return output;}class Circle:public Point{public:Circle(double a,double b,double c);void setr(double);double getr(){return r;}double area();friend ostream & operator<<(ostream & output,Circle & c);protected:double r;};Circle::Circle(double a,double b,double c):Point(a,b){r=c;}void Circle::setr(double c){r=c;}double Circle::area(){return 3.1415926*getr()*getr();}ostream & operator<<(ostream & output,Circle &c){output<<"圆心为：("<<c.x<<","<<c.y <<")"<<"半径为："<<c.getr()<<"面积为:"<<c.area()<<endl;return output;}class Cylinder:public Circle{public:Cylinder(double a,double b,double c,double d);double geth(){return h;}void seth(double d);double volume();double area();friend ostream & operator<<(ostream &output,Cylinder &cy);protected:double h;};Cylinder::Cylinder(double a,double b,double c,double d):Circle(a,b,c),h(d){}void Cylinder::seth(double d){h=d;}double Cylinder::volume(){return Circle::area()*h;}double Cylinder::area(){return 2*Circle::area()+2*3.1415926*getr()*h;}ostream & operator<<(ostream &output,Cylinder &cy){output<<"圆心为：("<<cy.x<<","<<cy.y <<")"<<"半径为："<<cy.getr()<<"面积为:"<<cy.area()<<"表面积为："<<cy.volume()<<endl;return output;}int main( )  {      Cylinder cy1(3.5,6.4,5.2,10);      cout<<"\noriginal cylinder:\nx="<<cy1.getx( )<<", y="<<cy1.gety( )<<", r="          <<cy1.getr( )<<", h="<<cy1.geth( )<<"\narea="<<cy1.area()          <<",volume="<<cy1.volume()<<endl;      cy1.seth(15);           cy1.setr(7.5);            cy1.setpoint(5,5);             cout<<"\nnew cylinder:\n"<<cy1;              system("pause");      return 0;  } original cylinder:x=3.5, y=6.4, r=5.2, h=10area=496.623,volume=849.487new cylinder:圆心为：(5,5)半径为：7.5面积为:1060.29表面积为：2650.72请按任意键继续. . .

经验积累：在定义派生类构造函数时，要调用基类的构造函数;

                    在用到基类和派生类同名的函数时要写明作用域

 上机感言：小小字符不可忽视，忘写<<和;导致出现好多bug;