C / C++ / MFC

// Minor example
template<clas T> // T can be almost any type
class my_class
{
public:
    typedef std::vector<T> array_type;
    void resize(int d1,int d2)
    {
        unsigned new_size = abs(d1) + abs(d1);
        // It must be an odd number so that we
        // can have a center index value from which
        // to offset from.
        if( !(new_size & 1) )
            ++new_size;
        data_array.resize(new_size);
        center_index = new_size>>1;
    }
    const T& get_at(int index) // operator[] would call this
    {
        unsigned new_index = center_index + index;
        // This is probably not need, because
        // the vector class will probably throw an error.
        if( new_index >= data_array.size() )
            throw(range_error );
        data_array[new_index];
    }
protected:
    // Single dimension array
    array_type data_array;
    unsigned center_index.
};