Program in C++ to add two 3 x. 3 matrices.

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Write a program in C++ to add two 3 x. 3 matrices. Define proper class, constructor, destructor and methods in the program.

BACHELOR OR COMPUTER APPLIATIONS (BCA) (REVISED)
Term-End Examination
June, 2020
BCS-031 : PROGRAMMING IN C++

Here’s an example of a C++ program that defines a Matrix class, including a constructor, destructor, and a method to add two 3×3 matrices:

#include <iostream>

class Matrix {
private:
    int rows;
    int cols;
    int **data;

public:
    // Constructor to initialize the matrix
    Matrix(int numRows, int numCols) : rows(numRows), cols(numCols) {
        data = new int *[rows];
        for (int i = 0; i < rows; ++i) {
            data[i] = new int[cols];
        }
    }

    // Destructor to deallocate memory
    ~Matrix() {
        for (int i = 0; i < rows; ++i) {
            delete[] data[i];
        }
        delete[] data;
    }

    // Method to input values into the matrix
    void inputValues() {
        std::cout << "Enter matrix values:" << std::endl;
        for (int i = 0; i < rows; ++i) {
            for (int j = 0; j < cols; ++j) {
                std::cin >> data[i][j];
            }
        }
    }

    // Method to add two matrices
    Matrix add(Matrix &other) {
        Matrix result(rows, cols);
        for (int i = 0; i < rows; ++i) {
            for (int j = 0; j < cols; ++j) {
                result.data[i][j] = data[i][j] + other.data[i][j];
            }
        }
        return result;
    }

    // Method to display the matrix
    void display() {
        for (int i = 0; i < rows; ++i) {
            for (int j = 0; j < cols; ++j) {
                std::cout << data[i][j] << " ";
            }
            std::cout << std::endl;
        }
    }
};

int main() {
    Matrix matrix1(3, 3);
    Matrix matrix2(3, 3);

    std::cout << "Enter values for matrix 1:" << std::endl;
    matrix1.inputValues();

    std::cout << "Enter values for matrix 2:" << std::endl;
    matrix2.inputValues();

    Matrix sumMatrix = matrix1.add(matrix2);

    std::cout << "Matrix 1:" << std::endl;
    matrix1.display();

    std::cout << "Matrix 2:" << std::endl;
    matrix2.display();

    std::cout << "Sum of matrices:" << std::endl;
    sumMatrix.display();

    return 0;
}

In this program, we define a Matrix class with a constructor to allocate memory for the matrix, a destructor to deallocate memory, methods to input values, add matrices, and display matrices. The main function demonstrates how to use the Matrix class to add two 3×3 matrices and display the results.

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