Overflow in calculation area of rectangle

[gduong]

I am so confused on why i am getting a overflow for my rectangle. void calcArea(){area=length*width;} . I have been staring at it for 30 mins and i can't figure out why.

  #include <iostream>
using namespace std;

class BasicShape{
protected:
	double area;
public:
	double getArea(){return area;}
	virtual void calcArea()=0;
};

class Circle: public BasicShape{
private:
	double centerX;
	double centerY;
	double radius;
public:
	/*
	Circle()
	{centerX = 0;
	centerY = 0;
	radius = 0;
	calcArea();}
	*/

	//circle constructor
	Circle(double X, double Y, double r)
	{centerX = X;
	centerY = Y;
	radius = r;
	calcArea();}
	//get mothods
	double getCenterX() {return centerX;}
	double getCenterY(){return centerY;}
	//area finder
	void calcArea(){area = 3.14 * radius * radius;}
};

	
class Rectangle: public BasicShape{
private:
	double width;
	double length;
public:
//rectangle constructor
	Rectangle(double l,double w){length =l, width=w;}
//get methods
double getWidth(){return width;}
double getLength(){return length;}
//area finder
void calcArea(){area=length*width;}
};

int main()
{
	//create an object for circle
	Circle c(2,2,10);
	//create an object for Rectangle
	Rectangle r(10,5);

	//Display circle object data
	cout << "Circle object data " << endl;
	cout << "Center x:" <<c.getCenterX()<<endl;
	cout << "Center y:" <<c.getCenterY()<<endl;
	cout << "Area    :" <<c.getArea()<<endl;

	//Display Rectnagle object data
	cout << "Rectangle object data: " <<endl;
	cout << "Length :" <<r.getLength()<<endl;
	cout << "Width  :" <<r.getWidth() <<endl;
	cout << "Area   :" <<r.getArea() <<endl;

	return 0;
}

[TwilightSpectre]

Its not overflowing, you just aren't getting initialized data. You never call 'calcarea()' on your Rectangle, maybe put it into the constructor?

[Austin J]

Yeah, maybe read this?

http://stackoverflow.com/questions/22002588/is-the-code-sample-about-variable-initialization-correct/22003023#22003023

[gduong]

Hmm, Sorry i am still confused. calcarea() is just to calculate the area. i am calling r.getArea() from the basic shape class.

[Volatile Pulse]

NT3 wrote:

Its not overflowing, you just aren't getting initialized data. You never call 'calcarea()' on your Rectangle, maybe put it into the constructor?

NT3 was referring to this:

Circle(double X, double Y, double r)
	{centerX = X;
	centerY = Y;
	radius = r;
	calcArea();}
// ...
Rectangle(double l,double w){length =l, width=w;}

You don't call calcArea() within your Rectangle constructor. This is why your area is wrong.

Try this:
Rectangle(double l,double w){length =l, width=w;calcArea();}

[gduong]

Damn i am so bad. I understand now. Ty very much