How do you dynamically allocate a matrix?

Question

How do you dynamically allocate a 2D matrix in C++? I have tried based on what I already know:

#include 

int main(){
    int rows;
    int c         


        

Answer 1

Here is the most clear & intuitive way i know to allocate a dynamic 2d array in C++. Templated in this example covers all cases.

template T** matrixAllocate(int rows, int cols, T **M)
{
    M = new T*[rows];
    for (int i = 0; i < rows; i++){
        M[i] = new T[cols];
    }
    return M;
}

... 

int main()
{
    ...
    int** M1 = matrixAllocate(rows, cols, M1);
    double** M2 = matrixAllocate(rows, cols, M2);
    ...
}