// -*- C++ -*-
//===---------------------------- array -----------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_ARRAY
#define _LIBCPP_ARRAY

/*
    array synopsis

namespace std
{
template <class T, size_t N > 
struct array
{ 
    // types: 
    typedef T & reference; 
    typedef const T & const_reference; 
    typedef implementation defined iterator; 
    typedef implementation defined const_iterator; 
    typedef size_t size_type; 
    typedef ptrdiff_t difference_type; 
    typedef T value_type; 
    typedef T* pointer;
    typedef const T* const_pointer;
    typedef std::reverse_iterator<iterator> reverse_iterator; 
    typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 

    // No explicit construct/copy/destroy for aggregate type 
    void fill(const T& u); 
    void swap(array& a);

    // iterators: 
    iterator begin(); 
    const_iterator begin() const; 
    iterator end(); 
    const_iterator end() const; 

    reverse_iterator rbegin(); 
    const_reverse_iterator rbegin() const; 
    reverse_iterator rend(); 
    const_reverse_iterator rend() const; 

    const_iterator cbegin() const; 
    const_iterator cend() const; 
    const_reverse_iterator crbegin() const;
    const_reverse_iterator crend() const; 

    // capacity: 
    constexpr size_type size() const; 
    constexpr size_type max_size() const; 
    bool empty() const; 

    // element access: 
    reference operator[](size_type n); 
    const_reference operator[](size_type n) const; 
    const_reference at(size_type n) const; 
    reference at(size_type n); 

    reference front(); 
    const_reference front() const; 
    reference back(); 
    const_reference back() const; 

    T* data(); 
    const T* data() const; 
};

template <class T, size_t N> 
  bool operator==(const array<T,N>& x, const array<T,N>& y); 
template <class T, size_t N> 
  bool operator!=(const array<T,N>& x, const array<T,N>& y); 
template <class T, size_t N> 
  bool operator<(const array<T,N>& x, const array<T,N>& y); 
template <class T, size_t N> 
  bool operator>(const array<T,N>& x, const array<T,N>& y); 
template <class T, size_t N> 
  bool operator<=(const array<T,N>& x, const array<T,N>& y); 
template <class T, size_t N> 
  bool operator>=(const array<T,N>& x, const array<T,N>& y); 

template <class T, size_t N > 
  void swap(array<T,N>& x, array<T,N>& y); 

template <class T> class tuple_size; 
template <int I, class T> class tuple_element; 
template <class T, size_t N> struct tuple_size<array<T, N>>;
template <int I, class T, size_t N> struct tuple_element<I, array<T, N>>; 
template <int I, class T, size_t N> T& get(array<T, N>&); 
template <int I, class T, size_t N> const T& get(const array<T, N>&); 

}  // std

*/

#include <__config>
#include <__tuple>
#include <type_traits>
#include <utility>
#include <iterator>
#include <algorithm>
#include <stdexcept>
#if defined(_LIBCPP_NO_EXCEPTIONS)
    #include <cassert>
#endif

#pragma GCC system_header

_LIBCPP_BEGIN_NAMESPACE_STD

template <class _Tp, size_t _Size> 
struct array
{
    // types:
    typedef array __self;
    typedef _Tp                                   value_type; 
    typedef value_type&                           reference; 
    typedef const value_type&                     const_reference; 
    typedef value_type*                           iterator;
    typedef const value_type*                     const_iterator;
    typedef value_type*                           pointer;
    typedef const value_type*                     const_pointer;
    typedef size_t                                size_type; 
    typedef ptrdiff_t                             difference_type; 
    typedef std::reverse_iterator<iterator>       reverse_iterator; 
    typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 

    value_type __elems_[_Size > 0 ? _Size : 1];

    // No explicit construct/copy/destroy for aggregate type 
    _LIBCPP_INLINE_VISIBILITY void fill(const value_type& __u) {_STD::fill_n(__elems_, _Size, __u);}
    _LIBCPP_INLINE_VISIBILITY void swap(array& __a) {_STD::swap_ranges(__elems_, __elems_ + _Size, __a.__elems_);}

    // iterators: 
    _LIBCPP_INLINE_VISIBILITY iterator begin()             {return iterator(__elems_);}
    _LIBCPP_INLINE_VISIBILITY const_iterator begin() const {return const_iterator(__elems_);}
    _LIBCPP_INLINE_VISIBILITY iterator end()               {return iterator(__elems_ + _Size);}
    _LIBCPP_INLINE_VISIBILITY const_iterator end() const   {return const_iterator(__elems_ + _Size);}

    _LIBCPP_INLINE_VISIBILITY reverse_iterator rbegin()             {return reverse_iterator(end());}
    _LIBCPP_INLINE_VISIBILITY const_reverse_iterator rbegin() const {return const_reverse_iterator(end());}
    _LIBCPP_INLINE_VISIBILITY reverse_iterator rend()               {return reverse_iterator(begin());}
    _LIBCPP_INLINE_VISIBILITY const_reverse_iterator rend() const   {return const_reverse_iterator(begin());}

    _LIBCPP_INLINE_VISIBILITY const_iterator cbegin() const          {return begin();}
    _LIBCPP_INLINE_VISIBILITY const_iterator cend() const            {return end();}
    _LIBCPP_INLINE_VISIBILITY const_reverse_iterator crbegin() const {return rbegin();}
    _LIBCPP_INLINE_VISIBILITY const_reverse_iterator crend() const   {return rend();}

    // capacity: 
    _LIBCPP_INLINE_VISIBILITY /*constexpr*/ size_type size() const      {return _Size;}
    _LIBCPP_INLINE_VISIBILITY /*constexpr*/ size_type max_size() const  {return _Size;}
    _LIBCPP_INLINE_VISIBILITY bool empty() const                    {return _Size == 0;}

    // element access: 
    _LIBCPP_INLINE_VISIBILITY reference operator[](size_type __n)             {return __elems_[__n];}
    _LIBCPP_INLINE_VISIBILITY const_reference operator[](size_type __n) const {return __elems_[__n];}
    reference at(size_type __n); 
    const_reference at(size_type __n) const; 

    _LIBCPP_INLINE_VISIBILITY reference front()             {return __elems_[0];}
    _LIBCPP_INLINE_VISIBILITY const_reference front() const {return __elems_[0];}
    _LIBCPP_INLINE_VISIBILITY reference back()              {return __elems_[_Size > 0 ? _Size-1 : 0];}
    _LIBCPP_INLINE_VISIBILITY const_reference back() const  {return __elems_[_Size > 0 ? _Size-1 : 0];}

    _LIBCPP_INLINE_VISIBILITY value_type* data()             {return __elems_;}
    _LIBCPP_INLINE_VISIBILITY const value_type* data() const {return __elems_;} 
};

template <class _Tp, size_t _Size> 
typename array<_Tp, _Size>::reference
array<_Tp, _Size>::at(size_type __n)
{
    if (__n >= _Size)
#ifndef _LIBCPP_NO_EXCEPTIONS
        throw out_of_range("array::at");
#else
        assert(!"array::at out_of_range");
#endif
    return __elems_[__n];
}

template <class _Tp, size_t _Size> 
typename array<_Tp, _Size>::const_reference
array<_Tp, _Size>::at(size_type __n) const
{
    if (__n >= _Size)
#ifndef _LIBCPP_NO_EXCEPTIONS
        throw out_of_range("array::at");
#else
        assert(!"array::at out_of_range");
#endif
    return __elems_[__n];
}

template <class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY inline
bool
operator==(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
{
    return _STD::equal(__x.__elems_, __x.__elems_ + _Size, __y.__elems_);
}

template <class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY inline
bool
operator!=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
{
    return !(__x == __y);
}

template <class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY inline
bool
operator<(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
{
    return _STD::lexicographical_compare(__x.__elems_, __x.__elems_ + _Size, __y.__elems_, __y.__elems_ + _Size);
}

template <class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY inline
bool
operator>(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
{
    return __y < __x;
}

template <class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY inline
bool
operator<=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
{
    return !(__y < __x);
}

template <class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY inline
bool
operator>=(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
{
    return !(__x < __y);
}

template <class _Tp, size_t _Size> 
_LIBCPP_INLINE_VISIBILITY inline
void
swap(const array<_Tp, _Size>& __x, const array<_Tp, _Size>& __y)
{
    __x.swap(__y);
}

template <class _Tp, size_t _Size>
  class tuple_size<array<_Tp, _Size> > : public integral_constant<size_t, _Size> {};

template <class _Tp, size_t _Size>
  class tuple_size<const array<_Tp, _Size> > : public integral_constant<size_t, _Size> {};

template <size_t _Ip, class _Tp, size_t _Size>
class tuple_element<_Ip, array<_Tp, _Size> >
{
public:
    typedef _Tp type;
};

template <size_t _Ip, class _Tp, size_t _Size>
class tuple_element<_Ip, const array<_Tp, _Size> >
{
public:
    typedef const _Tp type;
};

template <size_t _Ip, class _Tp, size_t _Size>
_LIBCPP_INLINE_VISIBILITY inline
_Tp&
get(array<_Tp, _Size>& __a)
{
    return __a[_Ip];
}

template <size_t _Ip, class _Tp, size_t _Size>
_LIBCPP_INLINE_VISIBILITY inline
const _Tp&
get(const array<_Tp, _Size>& __a)
{
    return __a[_Ip];
}

_LIBCPP_END_NAMESPACE_STD

#endif  // _LIBCPP_ARRAY