I have to write a program that outputs the length and width of a rectangle and then calculates and outputs the area, using a class called rectangle...

I thought I was about done, but when I run the program it says width, length and area are being used without being intitialized...

Here is my code...

the header file...

class Rectangle
{

private:

	int _width;
	int _length;
	int _area;

public:

	void SetDimensions( int width, int length, int area );
	void GetDimensions( int &width, int &length );
	void GetArea( int &area, int &width, int &length );
	void DisplayDimensions();
	void HoldScreen();
	Rectangle();

	~Rectangle();
};

function definitions...

#include<iostream>
#include "oRectangle.h"
using namespace std;

Rectangle::Rectangle()
{
	_width = 0;
	_length = 0;
	_area = 0;
	
}

Rectangle::~Rectangle(){}

void Rectangle::SetDimensions( int width, int length, int area )
{
	_width = width;
	_length = length;
	_area = area;
}

void Rectangle::GetDimensions( int &width, int &length )
{
	cout << "Enter the length of the rectangle: ";
	cin  >> _length;
	cout << "Enter the width of the rectangle: ";
	cin  >> _width;

}

void Rectangle::GetArea( int &area, int &width, int &length )
{
	area = ( _width * _length );
}

void Rectangle::DisplayDimensions()
{

	cout << "Length of Rectangle: " << _length;
	cout << "Width of Rectangle: " << _width;
	cout << "So Area of Rectangle: " << _area;
	cin.ignore( 99, '\n' );

}

void Rectangle::HoldScreen()
{
	cout << "Return to continue";
	cin.ignore( 99, '\n' );
}

and main...

#include<iostream>
#include "oRectangle.h"
using namespace std;

int main()

{

	int width;
	int length;
	int area;

	Rectangle d;

	d.SetDimensions( width, length, area );
	d.GetDimensions( width, length );
	d.GetArea( area, width, length );
	d.DisplayDimensions();
	d.HoldScreen();

}

Didn't I initialize them in my constructor?

Rectangle::Rectangle()
{
	_width = 0;
	_length = 0;
	_area = 0;
	
}

You don't seem to understand the concept of using an object. An object has its own data members, which are abstracted from a function like main(). Once you set the rectangle's width and length, you don't need to keep on passing 'length' and 'width' as arguments to a function unless you plan on changing some data. The rectangle already knows its height and width.

>Didn't I initialize them in my constructor?
You initialized _width, _length, and _area in your constructor. What you didn't initialize were the variables that you declared in main(). Those won't get initialized by your constructor.

You don't seem to understand the concept of using an object. An object has its own data members, which are abstracted from a function like main(). Once you set the rectangle's width and length, you don't need to keep on passing 'length' and 'width' as arguments to a function unless you plan on changing some data. The rectangle already knows its height and width.

>Didn't I initialize them in my constructor?
You initialized _width, _length, and _area in your constructor. What you didn't initialize were the variables that you declared in main(). Those won't get initialized by your constructor.

edit
Nevermind. I understand now, thank you very much.

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