Implement matrix addition and multiplication.

Implement matrix addition and multiplication.:-

 #include <iostream>

#include <vector>

using namespace std;

// Function to perform matrix addition

vector<vector<int>> matrixAddition(const vector<vector<int>>& matrixA, const vector<vector<int>>& matrixB) {

    int rows = matrixA.size();

    int columns = matrixA[0].size();

    vector<vector<int>> result(rows, vector<int>(columns, 0));

    for (int i = 0; i < rows; i++) {

        for (int j = 0; j < columns; j++) {

            result[i][j] = matrixA[i][j] + matrixB[i][j];

        }

    }

    return result;

}

// Function to perform matrix multiplication

vector<vector<int>> matrixMultiplication(const vector<vector<int>>& matrixA, const vector<vector<int>>& matrixB) {

    int rowsA = matrixA.size();

    int columnsA = matrixA[0].size();

    int rowsB = matrixB.size();

    int columnsB = matrixB[0].size();

    if (columnsA != rowsB) {

        throw invalid_argument("Cannot multiply the matrices. Invalid dimensions.");

    }

    vector<vector<int>> result(rowsA, vector<int>(columnsB, 0));

    for (int i = 0; i < rowsA; i++) {

        for (int j = 0; j < columnsB; j++) {

            for (int k = 0; k < columnsA; k++) {

                result[i][j] += matrixA[i][k] * matrixB[k][j];

            }

        }

    }

    return result;

}

// Function to display a matrix

void displayMatrix(const vector<vector<int>>& matrix) {

    for (const auto& row : matrix) {

        for (const auto& element : row) {

            cout << element << " ";

        }

        cout << endl;

    }

    cout << endl;

}

int main() {

    // Example matrices

    vector<vector<int>> matrixA = {{1, 2, 3},

                                   {4, 5, 6},

                                   {7, 8, 9}};

    vector<vector<int>> matrixB = {{9, 8, 7},

                                   {6, 5, 4},

                                   {3, 2, 1}};

    // Matrix addition

    vector<vector<int>> additionResult = matrixAddition(matrixA, matrixB);

    cout << "Matrix Addition Result:" << endl;

    displayMatrix(additionResult);

    // Matrix multiplication

    vector<vector<int>> multiplicationResult = matrixMultiplication(matrixA, matrixB);

    cout << "Matrix Multiplication Result:" << endl;

    displayMatrix(multiplicationResult);

    return 0;

}