Example: Matrix Addition using Operator Overloading in C++

// Matrix Addition using Operator Overloading
#include <iostream>
#include <vector> // Using vector for simpler matrix representation

class Matrix {
private:
    int rows;
    int cols;
    std::vector<std::vector<int>> data;

public:
    // Constructor
    Matrix(int r, int c) : rows(r), cols(c) {
        data.resize(rows, std::vector<int>(cols));
    }

    // Function to set matrix elements
    void setElement(int r, int c, int value) {
        if (r >= 0 && r < rows && c >= 0 && c < cols) {
            data[r][c] = value;
        } else {
            std::cout << "Error: Index out of bounds." << std::endl;
        }
    }

    // Function to get matrix elements (optional, for completeness)
    int getElement(int r, int c) const {
        if (r >= 0 && r < rows && c >= 0 && c < cols) {
            return data[r][c];
        } else {
            std::cout << "Error: Index out of bounds." << std::endl;
            return 0; // Return a default value or throw an exception
        }
    }

    // Overload the + operator for matrix addition
    Matrix operator+(const Matrix& other) const {
        if (rows != other.rows || cols != other.cols) {
            std::cout << "Error: Matrix dimensions must be the same for addition." << std::endl;
            // Return a default empty matrix or throw an exception
            return Matrix(0, 0);
        }

        Matrix result(rows, cols);
        for (int i = 0; i < rows; ++i) {
            for (int j = 0; j < cols; ++j) {
                result.data[i][j] = this->data[i][j] + other.data[i][j];
            }
        }
        return result;
    }

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

int main() {
    // Step 1: Create two Matrix objects
    Matrix A(2, 3);
    Matrix B(2, 3);

    // Step 2: Set elements for Matrix A
    A.setElement(0, 0, 1); A.setElement(0, 1, 2); A.setElement(0, 2, 3);
    A.setElement(1, 0, 4); A.setElement(1, 1, 5); A.setElement(1, 2, 6);

    // Step 3: Set elements for Matrix B
    B.setElement(0, 0, 7); B.setElement(0, 1, 8); B.setElement(0, 2, 9);
    B.setElement(1, 0, 10); B.setElement(1, 1, 11); B.setElement(1, 2, 12);

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

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

    // Step 4: Add matrices using the overloaded + operator
    Matrix C = A + B;

    std::cout << "Matrix A + B (Resultant Matrix C):" << std::endl;
    C.display();
    std::cout << std::endl;

    // Example of incompatible matrix addition
    Matrix D(2,2);
    D.setElement(0,0,1); D.setElement(0,1,1);
    D.setElement(1,0,1); D.setElement(1,1,1);

    std::cout << "Attempting to add Matrix A (2x3) and Matrix D (2x2):" << std::endl;
    Matrix E = A + D; // This will trigger the error message
    E.display(); // Will display an empty matrix if dimensions mismatch
    
    return 0;
}