cpp_prac/vector/vec.h

#include <initializer_list>
#include <iterator>

typedef int T;
constexpr int INITIAL_LEN = 10;

class Vec {
    std::size_t cap;
    std::size_t w_idx;
    T *arr = nullptr;

    void resize(std::size_t newsize);

  public:
    Vec();
    explicit Vec(std::size_t);
    Vec(std::initializer_list<T>);
    Vec(const Vec &other);                // Copy
    Vec(Vec &&other) noexcept;            // Move
    Vec &operator=(const Vec &other);     // CopyAssign
    Vec &operator=(Vec &&other) noexcept; // MoveAssign
    ~Vec();                               // Destructor

    T &operator[](std::size_t) const noexcept;

    std::size_t size() const;
    std::size_t capacity() const noexcept;

    void push_back(const T &value); // May except
    void push_back(T &&value);
    void pop_back() noexcept;
    void clear() noexcept;

    using iterator = T *;
    using const_iterator = const T *;

    iterator begin() noexcept { return arr; }
    iterator end() noexcept { return arr + w_idx; }

    const_iterator begin() const noexcept { return arr; }
    const_iterator end() const noexcept { return arr + w_idx; }
};

// std::iterator<Vec> end() const noexcept;
// std::iterator begin() const noexcept;