2D Vectors

#include <iostream>
#include <vector>

using namespace std;

//Function to Print 2D Vector:
void printVector(vector<vector<int>>v) {
    for (int i = 0; i < v.size(); i++) {
        for (int j = 0; j < v[i].size(); j++) {
            cout << v[i][j] << " ";
        }
        cout << "\n";
    }
}


int main()
{
    freopen ("inputf.in", "r", stdin);
    freopen ("outputf.in", "w", stdout);
    /*
        int n;
        cin >> n;

        //Declaring and Initiallising 2D Vector v;
        vector<vector<int>> v1 {{10, 20, 30, 40, 50}, {1, 2, 3}, {12, 23, 34, 56}};

        printVector(v1);
    */

/****************************************************************/
/****************************************************************/

/*Creating 2D Vector with "USER DEFINED NUMBER OF COLUMNS" and "ELEMENTS":*/
    int row;
    cin >> row;

    vector<vector<int>> v(row);

    //Take the column's value from the user:
    for (int i = 0; i < v.size(); i++) {
        int col;
        cin >> col;     //Numeber of columns by the user

        v[i] = vector<int> (col); //Assigning Column Size by the uiser to the vector at v[i]

        //Assigning Different user input values to the vector:
        for (int j = 0; j < v[i].size(); j++) {
            cin >> v[i][j];
        }

    }

    printVector(v);


    cout<<"\n";


/*0000000000000000000000000000000000000000000000000000*/
/*0000000000000000000000000000000000000000000000000000*/


    /*
    //Only for 2D matrix: taking user input using "emplace_back()"
    vector<vector<int>> vec1(ROW);

    for (int i=0; i<ROW;i++) {
        for (int j=0;j<COL;j++) {
            int temp;
            cin>>temp;
            vec1[i].emplace_back(temp);
        }
    }
    */

/****************************************************************/
/****************************************************************/

    //Creating Vector with User defined Row and Column Size.
    int r, c;
    cin >> r >> c;

    vector<vector<int>> vec(r, vector<int>(c, 101));

    printVector(vec);




    return 0;


/*Let the input be:
5
5   10 20 30 40 50
3   100 200 300
4   1 2 3 4
2   1000 1000
1   100000

5 6
*/
}