// template9.cpp			By: Aiman Hanna -  ©1993-2005 Aiman Hanna

// This program illustrates Nontype template arguments. So far, we have used 
// types as template arguments using the class or typename keyword. Although typenames 
// are most common when using templates, there are other possibilities. Integer constants
// are a common example.

// In addition, the program illustrates that by using template arguments for the bounds,
// they become part of the type. This means that compatibility between variables of different
// sizes will be checked at compile time as part for the process of type checking, rather than
// needing to be checked at run time. 

//	Key Points: 	1) Nontype template arguments


#include <iostream.h>


template <typename T, int ROWS, int COLUMNS>
class Matrix  
{
 public:
	Matrix();
	void showInfo();
	void initMatrix();
 private: 
	 T dataArr[ROWS][COLUMNS];
};

template <typename T, int ROWS, int COLUMNS>
Matrix< T, ROWS, COLUMNS>::Matrix()
{
	cout << "Creating a matrix with " << ROWS << " rows, and " 
									<< COLUMNS << " columns." << endl;

}

template <typename T, int ROWS, int COLUMNS>
void Matrix<T, ROWS, COLUMNS>::initMatrix()
{
	int i, j;
	for (i = 0; i<= (ROWS - 1); i++)
	{
		for (j = 0; j <= (COLUMNS -1); j++)
		{
			 dataArr[i][j] =  i * j * 5;
		}
		
	}

}

template <typename T, int ROWS, int COLUMNS>
void Matrix<T, ROWS, COLUMNS>::showInfo()
{
	int i, j;
	for (i = 0; i <= (ROWS - 1); i++)
	{
		for (j = 0; j <= (COLUMNS -1); j++)
		{
			cout << dataArr[i][j] << '\t';
		}
		
		cout << endl;
	}

}


int main( )
{

	Matrix<int, 3, 4> m1;
	m1.initMatrix();
	m1.showInfo();
			
	cout << endl << endl;
 
 	Matrix<double, 4, 7> m2;
	m2.initMatrix();
	m2.showInfo();

	cout << endl << endl;
 
 	Matrix<int, 4, 7> m3;
	m3.initMatrix();
	m3.showInfo();


	cout << endl << endl;
 
 	Matrix<int, 3, 4> m4;
	m4.initMatrix();
	m4.showInfo();


	// The following would be illegal
	// m1 = m2;
	// m1 = m3;

	// However, this is okay. Because the row and columns sizes are known at compile 
	// time, the space for the elements can be allocated in an array, and does not 
	// need to be dynamically managed. 

	m1 = m4;

	cout << endl << endl;

    m1.showInfo();

return 0;
}


// The output of the program 
/*
Creating a matrix with 3 rows, and 4 columns.
0       0       0       0
0       5       10      15
0       10      20      30


Creating a matrix with 4 rows, and 7 columns.
0       0       0       0       0       0       0
0       5       10      15      20      25      30
0       10      20      30      40      50      60
0       15      30      45      60      75      90


Creating a matrix with 4 rows, and 7 columns.
0       0       0       0       0       0       0
0       5       10      15      20      25      30
0       10      20      30      40      50      60
0       15      30      45      60      75      90


Creating a matrix with 3 rows, and 4 columns.
0       0       0       0
0       5       10      15
0       10      20      30


0       0       0       0
0       5       10      15
0       10      20      30
*/