打卡5.22
class Circle{
private:
float r;
public:
Circle(float a)
{
r=a;
cout<<"Constructor called"<<endl;
}
Circle(Circle&c)
{ r=c.r;
cout<<"Copy constructor called"<<endl;
}
~Circle()
{
cout<<"Destructor called"<<endl;
}
float area()
{
return r*r*3.14;
}
float perimeter()
{
return 2*3.14*r;
}
};