#ifndef MT3Q6_H
#define MT3Q6_H
///////////////////////////////////////////////////////////////
// MT3Q6b.h - Alternate Matrix                               //
//                                                           //
// Jim Fawcett, CSE687 - Object Oriented Design, Spring 2012 //
///////////////////////////////////////////////////////////////

#include <vector>
#include <iostream>

template <typename T, int N>
class Row
{
public:
  Row();
  ///////////////////////////////////////////////////////
  // compiler generated assignment and copy are correct
  T& operator[](int i);
  T operator[](int i) const;
private:
  T Array[N];
};

template <typename T, int N>
Row<T,N>::Row()
{
  for(int i=0; i<N; ++i)
    Array[i] = T(0);
}

template <typename T, int N>
T& Row<T,N>::operator[](int i)
{
  if(i<0 || N<= i)
    throw std::exception("col index error");
  return Array[i];
}

template <typename T, int N>
T Row<T,N>::operator[](int i) const
{
  if(i<0 || N<= i)
    throw std::exception("row index error");
  return Array[i];
}

template <typename T, int M, int N>
class Matrix
{
public:
  typedef T* row;
  Matrix();
  ///////////////////////////////////////////////////////
  // compiler generated assignment and copy are correct
  row& operator[](size_t i);
  Row<T,N> operator[](size_t i) const;
  //////////////////////////////
  // alternate indexing scheme
  T& operator()(int i, int j);
  T operator()(int i, int j) const;
  size_t rows() const { return M; }
  size_t cols() const { return N; }
private:
  T Array[M][N];
  T* RowPointer;
};

template<typename T, int M, int N>
Matrix<T, M, N>::Matrix()
{
  for(size_t i=0; i<M; ++i)
  {
    for(size_t j=0; j<N; ++j)
    {
      Array[i][j] = T(0);
    }
  }
}

template<typename T, int M, int N>
typename Matrix<T,M,N>::row& Matrix<T,M,N>::operator[](size_t i)
{
  if(i<0 || M<=i)
    throw std::exception("row index error");
  RowPointer = &Array[i][0];
  return RowPointer;
}

template<typename T, int M, int N>
typename Row<T,N> Matrix<T,M,N>::operator[](size_t i) const
{
  if(i<0 || M<=i)
    throw std::exception("row index error");
  Row<T,N> row;
  for(int j=0; j<N; ++j)
    row[j] = Array[i][j];
  return row;
}

template <typename T, int M, int N>
T& Matrix<T,M,N>::operator()(int i, int j)
{
  if(i<0 || M<=i || j<0 || N<=j)
    throw std::exception("index error");
  return Array[i][j];
}

template <typename T, int M, int N>
T Matrix<T,M,N>::operator()(int i, int j) const
{
  if(i<0 || M<=i || j<0 || N<=j)
    throw std::exception("index error");
  return Array[i][j];
}

template <typename T,int M, int N>
void Display(const Matrix<T,M,N>& m)
{
  for(size_t i=0; i<m.rows(); ++i)
  {
    std::cout << "\n  ";
    for(size_t j=0; j<m.cols(); ++j)
      std::cout << m[i][j] << " ";
  }
  std::cout << "\n";
}

#endif