// Vector.h
//
// A class vector similar to the STL container vector.
// Version 1.0
//
// Included in this version:
//   vector(), vector(n), vector(init_list), ~vector()
//   size(), indexing operator

#ifndef _Vector_h_
#define _Vector_h_

#include <algorithm>
#include <initializer_list>

namespace CS142 {

template <class T>
class vector
{
public:
    vector() : buffer_(nullptr), size_(0) {}
    explicit vector(int n);
    vector(std::initializer_list<T> init_list);

    ~vector() { delete [] buffer_; }

    int size() const { return size_; }

    T & operator[](int i) { return buffer_[i]; }
    const T & operator[](int i) const { return buffer_[i]; }

private:
    T * buffer_;
        // points to a dynamically allocated array that
        // contains the vector elements
    int size_;
        // the number of elements in the vector (and the size of
        // the buffer)
};

template <class T>
vector<T>::vector(int n)
{
    if (n == 0) {
        buffer_ = nullptr;
        size_ = 0;
    }
    else {
        buffer_ = new T[n]{};
        size_ = n;
    }
}

template <class T>
vector<T>::vector(std::initializer_list<T> init_list)
{
    if (init_list.size() == 0) {
        buffer_ = nullptr;
        size_ = 0;
    }
    else {
        buffer_ = new T[init_list.size()];
        std::copy(init_list.begin(), init_list.end(), buffer_);
        size_ = init_list.size();
    }
}

} // namespace CS142

#endif