#include <iostream>
using namespace std;

class matrix{
  struct Array;
  Array *pArray;
public:
	class Dref;
matrix();
matrix( unsigned int k);
matrix( unsigned int w,unsigned int k);

/*construktor kopiujacy */
matrix(const matrix &);

~matrix();
matrix& operator=(const double*);
matrix& operator=(const matrix&);

matrix operator+ (const matrix &) const;
matrix  operator-(const matrix &) const;
matrix  operator*(const matrix &) const;

matrix & operator +=(const matrix &);
matrix & operator -=(const matrix &);
matrix & operator *=(const matrix &);



friend ostream& operator<<(ostream&, const matrix&);
friend istream& operator>>(istream&, const matrix&);

bool operator==(const matrix&) const;


double operator()(unsigned int i,unsigned int j) const;
Dref operator()(unsigned int i, unsigned int j);


double read(unsigned int i, unsigned int j);

  void write(double **);


};


class matrix:: Dref{
friend  class matrix;
matrix & m;
int i,j;

Dref(matrix &mtr, unsigned int ii, unsigned int jj): m(mtr), i(ii), j(jj)
{

};

public:
	operator double() const
	{
	cout << "operator double() const"<<endl;
	return m.pArray->read(i,j);
	}
};
inline double matrix::read(unsigned int i,unsigned int j)
{

 return &matrix[i][j];
}