2d vector

#include <iostream>
#include <vector>

int main() {
    // Step 1: Declare a 2D vector
    std::vector<std::vector<int>> twoDVector;

    // Step 2: Declare inner vectors and push them into the 2D vector
    std::vector<int> innerVector1 = {1, 2, 3};
    std::vector<int> innerVector2 = {4, 5, 6};
    std::vector<int> innerVector3 = {7, 8, 9};

    twoDVector.push_back(innerVector1);
    twoDVector.push_back(innerVector2);
    twoDVector.push_back(innerVector3);

    // Step 3: Access and modify elements in the 2D vector
    int element = twoDVector[1][2]; // Access element in the second row, third column
    twoDVector[0][1] = 10; // Modify element in the first row, second column

    // Step 4: Display the contents of the 2D vector
    for (const auto &row : twoDVector) {
        for (int value : row) {
            std::cout << value << " ";
        }
        std::cout << std::endl;
    }

    return 0;
}