2D Array Class

array2d.h

#include <cstddef>
#include <vector>

template <typename T>
class Array2D
{
public:
    Array2D()
        : height_(0), width_(0)
    {}

    Array2D(size_t height, size_t width, const T& init_with = T())
        : height_(height), width_(width),
            vec_(height_ * width_, init_with)
    {}
    
    void Resize(size_t height, size_t width, const T& init_with = T())
    {
        height_ = height;
        width_ = width;

        vec_.resize(height_ * width_, init_with);
    }

    const T& At(size_t row, size_t col) const
    { return vec_[row * width_ + col]; }

    T& At(size_t row, size_t col)
    { return vec_[row * width_ + col]; }

private:
    size_t height_;
    size_t width_;

    std::vector<T> vec_;
};