Cases on classes and objects

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Two cases about preliminary classes and objects

Design cube class

What we need to know is ：

Then design a class

**1. Global function **
class Cube
{
    
public:
	// Set length 
	void SetL(int L)
	{
    
		m_L = L;
	}
	// Get long 
	int GetL()
	{
    
		return m_L;
	}
	// Set the width 
	void SetW(int W)
	{
    
		m_W = W;
	}
	// Get the width 
	int GetW()
	{
    
		return m_W;
	}
	// Set high 
	void SetH(int H)
	{
    
		m_H = H;
	}
	// Get high 
	int GetH()
	{
    
		return m_H;
	}

	// Get the area 
	int CubeS()
	{
    
		return 2 * m_L * m_H + 2 * m_H * m_W + 2 * m_L * m_W;
	}
	int CubeV()
	{
    
		return m_L * m_W * m_H;
	}
private:
	int m_L;
	int m_H;
	int m_W;
};

// Global function 
bool isSame(Cube& p1, Cube& p2)
{
    
	if (p1.GetL()==p2.GetL() && p1.GetH()== p2.GetH() && p1.GetW() == p2.GetW())
	{
    
		return true;
	}
	return false;
}

int main()
{
    
	// object 1
	Cube cb1;
	cb1.SetL(10);
	cb1.SetW(10);
	cb1.SetH(10);

	// object 2
	Cube cb2;
	cb2.SetL(10);
	cb2.SetW(10);
	cb2.SetH(10);

	cout << "cb1 The area of is ：" << cb1.CubeS() << endl;
	cout << "cb1 The volume of is ：" << cb1.CubeV() << endl;
	cout << "cb2 The area of is ：" << cb2.CubeS() << endl;
	cout << "cb2 The volume of is ：" << cb2.CubeV() << endl;
	bool ret = isSame(cb1, cb2);
	if (ret == true)
	{
    
		cout << " Two cubes are equal " << endl;
	}
	else
	{
    
		cout << " It's not equal " << endl;
	}
	return 0;
}

2. Member functions 
class Cube
{
    
public:
	// Set length 
	void SetL(int L)
	{
    
		m_L = L;
	}
	// Get long 
	int GetL()
	{
    
		return m_L;
	}
	// Set the width 
	void SetW(int W)
	{
    
		m_W = W;
	}
	// Get the width 
	int GetW()
	{
    
		return m_W;
	}
	// Set high 
	void SetH(int H)
	{
    
		m_H = H;
	}
	// Get high 
	int GetH()
	{
    
		return m_H;
	}

	// Get the area 
	int CubeS()
	{
    
		return 2 * m_L * m_H + 2 * m_H * m_W + 2 * m_L * m_W;
	}
	int CubeV()
	{
    
		return m_L * m_W * m_H;
	}
	// Compare member functions 
	// Compare the parameters of the passed cube with the attributes in the existing class 
	bool isSame(Cube&p)
	{
    
		if (m_L== p.GetL() && m_H == p.GetH() &&m_W == p.GetW())
		{
    
			return true;
		}
		return false;
	}
private:
	int m_L;
	int m_H;
	int m_W;
};

// Global function 
//bool isSame(Cube& p1, Cube& p2)
//{
    
//	if (p1.GetL()==p2.GetL() && p1.GetH()== p2.GetH() && p1.GetW() == p2.GetW())
//	{
    
//		return true;
//	}
//	return false;
//}

int main()
{
    
	// object 1
	Cube cb1;
	cb1.SetL(10);
	cb1.SetW(10);
	cb1.SetH(10);

	// object 2
	Cube cb2;
	cb2.SetL(10);
	cb2.SetW(10);
	cb2.SetH(11);

	cout << "cb1 The area of is ：" << cb1.CubeS() << endl;
	cout << "cb1 The volume of is ：" << cb1.CubeV() << endl;
	cout << "cb2 The area of is ：" << cb2.CubeS() << endl;
	cout << "cb2 The volume of is ：" << cb2.CubeV() << endl;
	bool ret = cb1.isSame(cb2);
	if (ret == true)
	{
    
		cout << " Two cubes are equal " << endl;
	}
	else
	{
    
		cout << " It's not equal " << endl;
	}
	return 0;
}

The relationship between a point and a circle

From the topic we can deduce ：

class Point
{
    
public:
	// Set up X
	void SetX(int x)
	{
    
		m_x = x;
	}
	// obtain X
	int GetX()
	{
    
		return m_x;
	}
	// Set up Y
	void SetY(int y)
	{
    
		m_y = y;
	}
	// obtain Y
	int GetY()
	{
    
		return m_y;
	}
private:
	int m_x;
	int m_y;
};

class Circle
{
    
public :
	// Set the radius 
	void SetRadius(int r)
	{
    
		m_R = r;
	}
	// Get the radius 
	int GetRadius()
	{
    
		return m_R;
	}
	// Set the center 
	void SetCenter(Point p)
	{
    
		
		m_Center = p;
	}
	// Get the center 
	Point GetCenter()
	{
    
		return m_Center;
	}
private:
	int m_R;// radius 
	Point m_Center;// center of a circle   // Another class is used here 
};

// Judge 
void isSame(Circle& p1, Point& q)
{
    
	// Get the distance between the point and the center of the circle 
	int distance =
		(p1.GetCenter().GetX() - q.GetX()) * (p1.GetCenter().GetX() - q.GetX()) +
		(p1.GetCenter().GetY() - q.GetY()) * (p1.GetCenter().GetY() - q.GetY());
	int distance2 = p1.GetRadius() * p1.GetRadius();// Square of radius 
	if (distance == distance2)
	{
    
		cout << " Point on the circle " << endl;
	}
	else if (distance < distance2)
	{
    
		cout << " The point is in the circle " << endl;
	}
	else
	{
    
		cout << " The point is outside the circle " << endl;
	}

}
int main()
{
    
	// Create circles 
	Circle c1;
	c1.SetRadius(10);
	// Create center point 
	Point p;
	p.SetX(10);// Abscissa 
	p.SetY(0);// Ordinate 
	// Set the center 
	c1.SetCenter(p);

	// Create points 
	Point p2;
	p2.SetX(10);
	p2.SetY(11);

	// The comparison 
	isSame(c1, p2);
}

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