Setting pointer to arbitrary dimension array?

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Even though this whole question is an indication of a design flaw, you can (sort of) accomplish this:

template<typename T>
class MultiArray
{
public:
    MultiArray(std::size_t dimen, std::size_t dimen_size) : _dimensions(dimen)
    {
        _data = new T[dimen * dimen_size];
    }

    // implment copy constructor, copy-assignment operator, destructor, and move constructors as well

    T* operator[](int i)
    {
        assert(0 <= i && i < _dimensions); // bounds check for your dimension
        return &_data[i];
    }
private:
    T* _data;
    std::size_t _dimensions;
};

int main()
{
    MultiArray<int> a(5, 2);
    a[4][1] = 3;
    std::cout << a[4][1] << std::endl;
    return 0;
}

If you want it jagged, you would have to do more math and maintenance regarding the bounds for each “dimension”.

The problem you run into has making the dimensions mean something for your application. Typically, a multi-dimensional array represents something (e.g. a 2D vector can represent Cartesian space, a 3D or 4D vector can be used for manipulating data for 3D graphics). Beyond the 4th dimension, finding a valid meaning for the array becomes murky and maintaining the logic behind it becomes increasingly complex with each new dimension.

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