// Program to perform matrix manipulation with the aid of a Class.
// Assignment-21
// matmanip.cpp, Author - Krishna Kumar Khatri.

// Uncomment ONLY the following line if you are using Turbo/Borland compiler.
// #define TC
#ifdef TC
	#include <iostream.h>
	#include <iomanip.h>
#else
	#include <iostream>
	#include <iomanip>
	using namespace std;
#endif
#include <conio.h>  // For getch.
const int MAXMATSIZE = 5;

class Matrix
{
        int* mat[MAXMATSIZE];
        int row, col;
    public:
        Matrix(const int& = 0, const int& = 0);
        void initialize(const int& = 0);
        void addition(const Matrix&, const Matrix&);
        void subtraction(const Matrix&, const Matrix&);
        void multiplication(const Matrix&, const Matrix&);
        int comparison(const Matrix&, const Matrix&);
        void display();
};

Matrix::Matrix(const int& r, const int& c)
    { row = r; col = c; }

void Matrix::initialize(const int& init)
{
    int i, j;
    
    if (init != 0) {
        cout << "Enter " << row*col << " matrix elements: ";
        for (i = 0; i < row; i++)
            for (j = 0; j < col; j++) {
                mat[i + j] = new int;     // Set aside memory.
                cin >> mat[i][j];
            }
    } else 
        for (i = 0; i < row; i++)
            for (j = 0; j < col; j++) {
                mat[i + j] = new int;     // Set aside memory.
                mat[i][j] = 0;
            }
}

void Matrix::addition(const Matrix& mat1, const Matrix& mat2)
{
    int i, j;
    
    for (i = 0; i < this->row; i++)
        for (j = 0; j < this->col; j++)
            this->mat[i][j] = mat1.mat[i][j] + mat2.mat[i][j];
}

void Matrix::subtraction(const Matrix& mat1, const Matrix& mat2)
{
    int i, j;
    
    for (i = 0; i < this->row; i++)
        for (j = 0; j < this->col; j++)
            this->mat[i][j] = mat1.mat[i][j] - mat2.mat[i][j];
}

void Matrix::multiplication(const Matrix& mat1, const Matrix& mat2)
{
    int i, j, k;
    
    if (mat1.col != mat2.row) {
        cout << "Cannot perform. Required condition failed.";
        return;
    }
    for (i = 0; i < mat1.row; i++)
        for (j = 0; j < mat2.col; j++)
            for (k = 0; k < mat2.col; k++)
                this->mat[i][j] += mat1.mat[i][k] * mat2.mat[k][j];
}

int Matrix::comparison(const Matrix& mat1, const Matrix& mat2)
{
    int i, j;
    
    if (mat1.row == mat2. row && mat1.col == mat2.col)
        for (i = 0; i < mat1.row; i++)
            for (j = 0; j < mat1.col; j++)
                if (mat1.mat[i][j] < mat2.mat[i][j])
                    return -1;
                else if (mat1.mat[i][j] > mat2.mat[i][j])
                    return 1;
    return 0;
}

void Matrix::display()
{
    int i, j;
    
    cout << endl;
    for (i = 0; i < row; i++) {
        for (j = 0; j < col; j++)
            cout << setw(4) << mat[i][j] << " ";
        cout << endl;
    }
}

int main()
{
    #ifdef TC
        clrscr();
    #endif
    int r, c;
    
    do {
        cout << "Row and column: ";
        cin >> r >> c;
    } while ((r < 1 || r > MAXMATSIZE) ||
             (c < 1 || c > MAXMATSIZE));
             
    // Declare the objects.
    Matrix a(r, c), b(r, c);
    Matrix res(r, c);
    
    // Initialize the members matrices.
    cout << "\nMatrix A. "; a.initialize(1);
    cout << "Matrix B. "; b.initialize(1);
    res.initialize(0);
    
    // Display them back to user.
    cout << "\nMatrix A, "; a.display();
    cout << "\nMatrix B, "; b.display();
    cout << "\nResultant Matrix, "; res.display();
    cout << "\nContinue..."; getch();
    
    // Perform addition, and display the result.
    res.addition(a, b);
    cout << "\n\nAddition Result,";
    res.display();
    cout << "\nContinue..."; getch();
    
    // Perform subtraction, and display the result.
    res.subtraction(a, b);
    cout << "\n\nSubtraction Result,";
    res.display();
    cout << "\nContinue..."; getch();

    // Perform subtraction, and display the result.
    // Reinitialize resultant matrix (required for clean-up).
    res.initialize(0);
    res.multiplication(a, b);
    cout << "\n\nMultiplication Result,";
    res.display();
    cout << "\nContinue..."; getch();

    // Perform subtraction, and display the result.
    // In the following stmt, the dummy phinomenon can be eliminated by
    // making comparison() function friend of the class, instead of member.
    int result = res.comparison(a, b);  // Here res is working as dummy.
    cout << "\n\nComparison Result,\n";
    result < 0 ? cout << "Matrix A < Matrix B" :
                 (result == 0 ? cout << "Matrix A = Matrix B" :
                                cout << "Matrix A > Matrix B");

    cout << endl << endl << "Program over. Press any key to exit...";
    getch();
    return 0; // Successful termination.
}