13【项目3 - 与圆心相连的直线】

最新推荐文章于 2014-09-02 08:31:15 发布

违规昵称1001

最新推荐文章于 2014-09-02 08:31:15 发布

阅读量546

点赞数

CC 4.0 BY-SA版权

本文链接：https://blog.youkuaiyun.com/u012368971/article/details/26360783

本文介绍了一个使用C++实现的圆形类，该类继承自点类，并实现了比较运算符重载及与点的位置关系判断等功能。文章通过具体实例展示了如何创建圆形对象并进行面积比较和位置判断。

/*
*Corpyright (c)2013,烟台大学计算机学院
*All right reseved.
*作者：张梦佳
*完成日期：2014年5月20日
*版本号：v1.0
*输入描述：
*问题描述:
*程序输出：
*问题分析：
*算法设计：
*/
#include <iostream>
#include <cmath>
using namespace std;
class Point
{
public:
    Point(double a=0,double b=0):x(a),y(b){}
    double getx()
    {
        return x;
    }
    double gety()
    {
        return y;
    }
    void display()
    {
        cout<<"("<<x<<","<<y<<")"<<endl;
    }
    friend ostream& operator<<(ostream&output,Point&s);
protected:
    double x;
    double y;
};
ostream& operator<<(ostream&output,Point&s)
{
    output<<"("<<s.getx()<<","<<s.gety()<<")"<<endl;
    return output;
}
class Circle:public Point
{
public:
    Circle(double a=0,double b=0,double c=0):Point(a,b),r(c){}
    double area()
    {
        return (3.14*r*r);
    }
    friend double locate(Point&s,Point&s1);
    friend ostream& operator<<(ostream&output,Circle&s);
    void jisuan(Point&q);
    double getr()
    {
        return r;
    }
    bool operator>(Circle&s);
    bool operator<=(Circle&s);
    bool operator<(Circle&s);
    bool operator>=(Circle&s);
    bool operator==(Circle&s);
    bool operator!=(Circle&s);
private:
    double r;
};
bool Circle::operator>(Circle&s)
{
    if(area()>s.area())
    return true;
    else
    return
    false;
}
bool Circle::operator<=(Circle&s)
{
    if(!(area()>s.area()))
    return true;
    else
    return
    false;
}
bool Circle::operator<(Circle&s)
{
    if(area()<s.area())
    return true;
    else
    return
    false;
}
bool Circle::operator==(Circle&s)
{
    if(area()==s.area())
    return true;
    else
    return
    false;
}
bool Circle::operator!=(Circle&s)
{
    if(area()!=s.area())
    return true;
    else
    return
    false;
}
bool Circle::operator>=(Circle&s)
{
    if(!(area()>s.area()))
    return true;
    else
    return false;
}
ostream& operator<<(ostream&output,Circle&s)
{
    output<<"("<<s.getx()<<","<<s.gety()<<","<<s.r<<")";
    return output;
}
double locate(Point&s,Circle&s1)
{
    double num,num1;
    num=sqrt((s1.getx()-s.getx())*(s1.getx()-s.getx())+(s1.gety()-s.gety())*(s1.gety()-s.gety()));
    num1=num-s1.getr();
    return num1;
}
void Circle::jisuan(Point&p)
{
    double num,num1,num2,num3,num4;;
    num=pow((y-p.gety())/(x-p.getx()),2)+1;
    num1=x+sqrt(r*r/num);
    num2=x-sqrt(r*r/num);
    num3=y+(y-p.gety())/(x-p.getx())*(num1-p.getx())+p.gety();
    num4=y+(y-p.gety())/(x-p.getx())*(num2-p.getx())+p.gety();
    Point c1(num1,num3),c2(num2,num4);
    c1.display();
    c2.display();

}
int main( )
{
	Circle c1(3,2,4),c2(4,5,5),c3(3,2,4);      //c2应该大于c1
	Point p1(1,1),p2(3,-2),p3(7,3);  //分别位于c1内、上、外


	cout<<"圆c1: "<<c1;

	cout<<"点p1: "<<p1;
	cout<<"点p1在圆c1之"<<((locate(p1, c1)>0)?"外":((locate(p1, c1)<0)?"内":"上"))<<endl;

	cout<<"点p2: "<<p2;
	cout<<"点p2在圆c1之"<<((locate(p2, c1)>0)?"外":((locate(p2, c1)<0)?"内":"上"))<<endl;

	cout<<"点p3: "<<p3;
	cout<<"点p3在圆c1之"<<((locate(p3, c1)>0)?"外":((locate(p3, c1)<0)?"内":"上"))<<endl;
	if(c1>c2)
	cout<<"c1"<<c1<<">"<<"c2"<<c2;
	else
	cout<<"c1"<<c1<<"<"<<"c2"<<c2;
	cout<<endl;
	if(c1==c3)
	cout<<"c1"<<c1<<"="<<"c3"<<c3;
	else
	cout<<"c1"<<c1<<"!="<<"c3"<<c3;
	cout<<endl;
	c1.jisuan(p3);
	return 0;
}