c 定义一个圆类.doc

class Circle //定义类
{
private:
double x,y,r;
public:
Circle(double x,double y,double r);
Circle();
void Move();
double Area(double x=0,double y=0,double r=1);
double Length(double x=0,double y=0,double r=1);
void Show();
};
#include<>
int main()
{
Circle c(,,),c1;
double A1,L1;
A1=();
L1=();
();
cout<<"A1="<<()<<endl;
cout<<"L1="<<()<<endl;
();
();
return 0;
}
Circle::Circle(double x1,double y1,double r1)
{
x=x1;
y=y1;
r=r1;
}
Circle::Circle()
{
}
void Circle::Move()
{
x=x+3;
y=y+6;
r=r+1;
}
double Circle::Area(double x,double y,double r)
{
return *r*r;
}
double Circle::Length(double x,double y,double r)
{
return 2**r;
}
void Circle::Show()
{
cout<<"("<<x<<","<<y<<")"<<endl;
cout<<"r="<<r<<endl;
}