Dynamic Multidimensional Array in C++

Question

The program should take a dimension n and make a multidimensional array of nxn dimensions, I know it has to be done with the new[ ] operator, thus it should be done using pointers, I found a lot of ways on the internet but I´m new to this topic and couldn't understand well how they work, here is one of those codes I found that claims to work:

main()
{
    double n;
    cout<<"Enter the n dimension to the matrix[nxn]: ";
    cin>>n;
    matrix=new int*[n];
    int *data=new int[n*n];
    for(i=0;i<n;i++)
      matrix[i]=&data[i*n];
}

My question is: is this code right? if so, how does it work? otherwise, which code does work? (if you could and a little explanation I'd appreciate it)

Answer 1

You should not use raw pointers, better use std::vector.

#include <iostream>
#include <vector>

int main() {
    int n;
    std::cin << n;

    std::vector<std::vector<int>> matrix(n, std::vector<int>(n));
    // Do whatever with matrix

    return 0;
}