第十一周

/*
* Copyright (c) 2014, 烟台大学计算机学院
* All rights reserved.
* 文件名称：test.cpp
* 作    者：张磊
* 版 本 号：v1.0
*
* 问题描述: 在圆类上重载关系运算符（6种），使之能够按圆的面积比较两个圆的大小。
* 程序输入：相应的程序
* 程序输出：对应得结果
*/

#include<iostream>
#include<cmath>
using namespace std;
class Point
{
public:
Point()
{
x=0;
y=0;
}
Point(int a,int b):x(a),y(b) {}
friend ostream& operator<<(ostream&,Point&);
protected:
double x;
double y;
};
ostream& operator<<(ostream&output,Point&p)
{
output<<"("<<p.x<<","<<p.y<<")";
return output;
}
class Circle:public Point
{
public:
Circle(double a=0,double b=0,double r=0):Point(a,b),radius(r) {}
double area();
friend ostream& operator<<(ostream&,Circle&);
bool operator>(Circle&);
bool operator>=(Circle&);
bool operator<(Circle&);
bool operator<=(Circle&);
bool operator==(Circle&);
bool operator!=(Circle&);
private:
double radius;
};
ostream& operator<<(ostream&output,Circle&c)
{
output<<"("<<c.x<<","<<c.y<<")";
cout<<"r="<<c.radius;
return output;
}
double Circle::area()
{
return (3.14*radius*ra
990d
dius);
}
bool Circle::operator>(Circle&c)
{
if(radius>c.radius)
return true;
else
return false;
}
bool Circle::operator<(Circle&c)
{
if(radius<c.radius)
return true;
else
return false;
}
bool Circle::operator==(Circle&c)
{
if(radius==c.radius)
return true;
else
return false;
}
bool Circle::operator>=(Circle&c)
{
if(radius<c.radius)
return false;
else
return true;
}
bool Circle::operator<=(Circle&c)
{
if(radius<c.radius)
return false;
else
return true;
}
bool Circle::operator!=(Circle&c)
{
if(radius==c.radius)
return false;
else
return true;
}
int main( )
{
Circle c1(3,2,4),c2(4,5,5);      //c2应该大于c1
cout<<"圆c1( "<<c1<<" )的面积是 "<<c1.area()<<endl;
cout<<"圆c2( "<<c2<<" )的面积是 "<<c2.area()<<endl;
cout<<"圆c1 ";
if(c1>c2) cout<<"大于, ";
if(c1<c2) cout<<"小于, ";
if(c1>=c2) cout<<"大于等于, ";
if(c1<=c2) cout<<"小于等于, ";
if(c1==c2) cout<<"等于, ";
if(c1!=c2) cout<<"不等于, ";
cout<<"圆c2"<<endl;
return 0;
}