[求助]请高手运行一下看看这个程序错在哪里
class point{
float x,y;
public:
Point(float a=0,float b=0){x=a;y=b}
void SetP(float a=0,float b=0){x=a;y=b}
void Display(){cout<<"位置是:("<<x<<","<<y<<")\n";}
};
class Circle:public Point{
float r;
public:
Circle(float z=1,float x=0,float y=0){r=z;}
void SetC(float z=1,float x=0,float y=0){r=z;SetP(x,y);}
void Print()
{ cout<<"圆的";
Display();
cout<<"圆的半径是:"<<r<<endl;
}
};
void main()
{ Circle a(3.2);
a.Print();
a.SetC(6,8,2);
a.Print();
}