STL/stl/inc/map

// map standard header

// Copyright (c) Microsoft Corporation.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

#pragma once
#ifndef _MAP_
#define _MAP_
#include <yvals_core.h>
#if _STL_COMPILER_PREPROCESSOR

#include <tuple>
#include <xtree>

#if _HAS_CXX17
#include <xpolymorphic_allocator.h>
#endif // _HAS_CXX17

#pragma pack(push, _CRT_PACKING)
#pragma warning(push, _STL_WARNING_LEVEL)
#pragma warning(disable : _STL_DISABLED_WARNINGS)
_STL_DISABLE_CLANG_WARNINGS
#pragma push_macro("new")
#undef new
_STD_BEGIN
template <class _Kty, // key type
    class _Ty, // mapped type
    class _Pr, // comparator predicate type
    class _Alloc, // actual allocator type (should be value allocator)
    bool _Mfl> // true if multiple equivalent keys are permitted
class _Tmap_traits { // traits required to make _Tree behave like a map
public:
    using key_type       = _Kty;
    using value_type     = pair<const _Kty, _Ty>;
    using key_compare    = _Pr;
    using allocator_type = _Alloc;
#if _HAS_CXX17
    using node_type = _Node_handle<_Tree_node<value_type, typename allocator_traits<_Alloc>::void_pointer>, _Alloc,
        _Node_handle_map_base, _Kty, _Ty>;
#endif // _HAS_CXX17

    static constexpr bool _Multi = _Mfl;

    template <class... _Args>
    using _In_place_key_extractor = _In_place_key_extract_map<_Kty, _Args...>;

    class value_compare {
    public:
        _CXX17_DEPRECATE_ADAPTOR_TYPEDEFS typedef value_type _FIRST_ARGUMENT_TYPE_NAME;
        _CXX17_DEPRECATE_ADAPTOR_TYPEDEFS typedef value_type _SECOND_ARGUMENT_TYPE_NAME;
        _CXX17_DEPRECATE_ADAPTOR_TYPEDEFS typedef bool _RESULT_TYPE_NAME;

        _NODISCARD bool operator()(const value_type& _Left, const value_type& _Right) const {
            // test if _Left precedes _Right by comparing just keys
            return comp(_Left.first, _Right.first);
        }

    protected:
        friend _Tree<_Tmap_traits>;

        value_compare(key_compare _Pred) : comp(_Pred) {}

        key_compare comp; // the comparator predicate for keys
    };

    template <class _Ty1, class _Ty2>
    static const _Kty& _Kfn(const pair<_Ty1, _Ty2>& _Val) { // extract key from element value
        return _Val.first;
    }
};

template <class _Kty, class _Ty, class _Pr = less<_Kty>, class _Alloc = allocator<pair<const _Kty, _Ty>>>
class map : public _Tree<_Tmap_traits<_Kty, _Ty, _Pr, _Alloc, false>> {
    // ordered red-black tree of {key, mapped} values, unique keys
public:
    static_assert(!_ENFORCE_MATCHING_ALLOCATORS || is_same_v<pair<const _Kty, _Ty>, typename _Alloc::value_type>,
        _MISMATCHED_ALLOCATOR_MESSAGE("map<Key, Value, Compare, Allocator>", "pair<const Key, Value>"));

    using _Mybase                = _Tree<_Tmap_traits<_Kty, _Ty, _Pr, _Alloc, false>>;
    using _Nodeptr               = typename _Mybase::_Nodeptr;
    using key_type               = _Kty;
    using mapped_type            = _Ty;
    using key_compare            = _Pr;
    using value_compare          = typename _Mybase::value_compare;
    using value_type             = pair<const _Kty, _Ty>;
    using allocator_type         = typename _Mybase::allocator_type;
    using size_type              = typename _Mybase::size_type;
    using difference_type        = typename _Mybase::difference_type;
    using pointer                = typename _Mybase::pointer;
    using const_pointer          = typename _Mybase::const_pointer;
    using reference              = value_type&;
    using const_reference        = const value_type&;
    using iterator               = typename _Mybase::iterator;
    using const_iterator         = typename _Mybase::const_iterator;
    using reverse_iterator       = typename _Mybase::reverse_iterator;
    using const_reverse_iterator = typename _Mybase::const_reverse_iterator;

    using _Alnode        = typename _Mybase::_Alnode;
    using _Alnode_traits = typename _Mybase::_Alnode_traits;

#if _HAS_CXX17
    using insert_return_type = _Insert_return_type<iterator, typename _Mybase::node_type>;
#endif // _HAS_CXX17

    map() : _Mybase(key_compare()) {}

    explicit map(const allocator_type& _Al) : _Mybase(key_compare(), _Al) {}

    map(const map& _Right) : _Mybase(_Right, _Alnode_traits::select_on_container_copy_construction(_Right._Getal())) {}

    map(const map& _Right, const allocator_type& _Al) : _Mybase(_Right, _Al) {}

    explicit map(const key_compare& _Pred) : _Mybase(_Pred) {}

    map(const key_compare& _Pred, const allocator_type& _Al) : _Mybase(_Pred, _Al) {}

    template <class _Iter>
    map(_Iter _First, _Iter _Last) : _Mybase(key_compare()) {
        insert(_First, _Last);
    }

    template <class _Iter>
    map(_Iter _First, _Iter _Last, const key_compare& _Pred) : _Mybase(_Pred) {
        insert(_First, _Last);
    }

    template <class _Iter>
    map(_Iter _First, _Iter _Last, const allocator_type& _Al) : _Mybase(key_compare(), _Al) {
        insert(_First, _Last);
    }

    template <class _Iter>
    map(_Iter _First, _Iter _Last, const key_compare& _Pred, const allocator_type& _Al) : _Mybase(_Pred, _Al) {
        insert(_First, _Last);
    }

    map& operator=(const map& _Right) {
        _Mybase::operator=(_Right);
        return *this;
    }

    map(map&& _Right) : _Mybase(_STD move(_Right)) {}

    map(map&& _Right, const allocator_type& _Al) : _Mybase(_STD move(_Right), _Al) {}

    map& operator=(map&& _Right) noexcept(_Alnode_traits::is_always_equal::value&& is_nothrow_move_assignable_v<_Pr>) {
        _Mybase::operator=(_STD move(_Right));
        return *this;
    }

    mapped_type& operator[](key_type&& _Keyval) { // find element matching _Keyval or insert value-initialized value
        return _Try_emplace(_STD move(_Keyval)).first->_Myval.second;
    }

    void swap(map& _Right) noexcept(noexcept(_Mybase::swap(_Right))) {
        _Mybase::swap(_Right);
    }

    using _Mybase::insert;

    template <class _Valty, enable_if_t<is_constructible_v<value_type, _Valty>, int> = 0>
    pair<iterator, bool> insert(_Valty&& _Val) {
        return this->emplace(_STD forward<_Valty>(_Val));
    }

    template <class _Valty, enable_if_t<is_constructible_v<value_type, _Valty>, int> = 0>
    iterator insert(const_iterator _Where, _Valty&& _Val) {
        return this->emplace_hint(_Where, _STD forward<_Valty>(_Val));
    }

private:
    template <class _Keyty, class... _Mappedty>
    pair<_Nodeptr, bool> _Try_emplace(_Keyty&& _Keyval, _Mappedty&&... _Mapval) {
        const auto _Loc = _Mybase::_Find_lower_bound(_Keyval);
        if (_Mybase::_Lower_bound_duplicate(_Loc._Bound, _Keyval)) {
            return {_Loc._Bound, false};
        }

        _Mybase::_Check_grow_by_1();

        const auto _Scary    = _Mybase::_Get_scary();
        const auto _Inserted = _Tree_temp_node<_Alnode>(_Mybase::_Getal(), _Scary->_Myhead, piecewise_construct,
            _STD forward_as_tuple(_STD forward<_Keyty>(_Keyval)),
            _STD forward_as_tuple(_STD forward<_Mappedty>(_Mapval)...))
                                   ._Release();

        // nothrow hereafter
        return {_Scary->_Insert_node(_Loc._Location, _Inserted), true};
    }

    template <class _Keyty, class... _Mappedty>
    _Nodeptr _Try_emplace_hint(const _Nodeptr _Hint, _Keyty&& _Keyval, _Mappedty&&... _Mapval) {
        const auto _Loc = _Mybase::_Find_hint(_Hint, _Keyval);
        if (_Loc._Duplicate) {
            return _Loc._Location._Parent;
        }

        _Mybase::_Check_grow_by_1();

        const auto _Scary    = _Mybase::_Get_scary();
        const auto _Inserted = _Tree_temp_node<_Alnode>(_Mybase::_Getal(), _Scary->_Myhead, piecewise_construct,
            _STD forward_as_tuple(_STD forward<_Keyty>(_Keyval)),
            _STD forward_as_tuple(_STD forward<_Mappedty>(_Mapval)...))
                                   ._Release();

        // nothrow hereafter
        return _Scary->_Insert_node(_Loc._Location, _Inserted);
    }

public:
    template <class... _Mappedty>
    pair<iterator, bool> try_emplace(const key_type& _Keyval, _Mappedty&&... _Mapval) {
        const auto _Result = _Try_emplace(_Keyval, _STD forward<_Mappedty>(_Mapval)...);
        return {iterator(_Result.first, _Mybase::_Get_scary()), _Result.second};
    }

    template <class... _Mappedty>
    iterator try_emplace(const const_iterator _Hint, const key_type& _Keyval, _Mappedty&&... _Mapval) {
        return iterator(
            _Try_emplace_hint(_Hint._Ptr, _Keyval, _STD forward<_Mappedty>(_Mapval)...), _Mybase::_Get_scary());
    }

    template <class... _Mappedty>
    pair<iterator, bool> try_emplace(key_type&& _Keyval, _Mappedty&&... _Mapval) {
        const auto _Result = _Try_emplace(_STD move(_Keyval), _STD forward<_Mappedty>(_Mapval)...);
        return {iterator(_Result.first, _Mybase::_Get_scary()), _Result.second};
    }

    template <class... _Mappedty>
    iterator try_emplace(const const_iterator _Hint, key_type&& _Keyval, _Mappedty&&... _Mapval) {
        return iterator(_Try_emplace_hint(_Hint._Ptr, _STD move(_Keyval), _STD forward<_Mappedty>(_Mapval)...),
            _Mybase::_Get_scary());
    }

private:
    template <class _Keyty, class _Mappedty>
    pair<_Nodeptr, bool> _Insert_or_assign(_Keyty&& _Keyval, _Mappedty&& _Mapval) {
        const auto _Loc = _Mybase::_Find_lower_bound(_Keyval);
        if (_Mybase::_Lower_bound_duplicate(_Loc._Bound, _Keyval)) {
            _Loc._Bound->_Myval.second = _STD forward<_Mappedty>(_Mapval);
            return {_Loc._Bound, false};
        }

        _Mybase::_Check_grow_by_1();

        const auto _Scary    = _Mybase::_Get_scary();
        const auto _Inserted = _Tree_temp_node<_Alnode>(
            _Mybase::_Getal(), _Scary->_Myhead, _STD forward<_Keyty>(_Keyval), _STD forward<_Mappedty>(_Mapval))
                                   ._Release();

        // nothrow hereafter
        return {_Scary->_Insert_node(_Loc._Location, _Inserted), true};
    }

    template <class _Keyty, class _Mappedty>
    _Nodeptr _Insert_or_assign_hint(const _Nodeptr _Hint, _Keyty&& _Keyval, _Mappedty&& _Mapval) {
        const auto _Loc = _Mybase::_Find_hint(_Hint, _Keyval);
        if (_Loc._Duplicate) {
            _Loc._Location._Parent->_Myval.second = _STD forward<_Mappedty>(_Mapval);
            return _Loc._Location._Parent;
        }

        _Mybase::_Check_grow_by_1();

        const auto _Scary    = _Mybase::_Get_scary();
        const auto _Inserted = _Tree_temp_node<_Alnode>(
            _Mybase::_Getal(), _Scary->_Myhead, _STD forward<_Keyty>(_Keyval), _STD forward<_Mappedty>(_Mapval))
                                   ._Release();

        // nothrow hereafter
        return _Scary->_Insert_node(_Loc._Location, _Inserted);
    }

public:
    template <class _Mappedty>
    pair<iterator, bool> insert_or_assign(const key_type& _Keyval, _Mappedty&& _Mapval) {
        const auto _Result = _Insert_or_assign(_Keyval, _STD forward<_Mappedty>(_Mapval));
        return {iterator(_Result.first, _Mybase::_Get_scary()), _Result.second};
    }

    template <class _Mappedty>
    iterator insert_or_assign(const const_iterator _Hint, const key_type& _Keyval, _Mappedty&& _Mapval) {
        return iterator(
            _Insert_or_assign_hint(_Hint._Ptr, _Keyval, _STD forward<_Mappedty>(_Mapval)), _Mybase::_Get_scary());
    }

    template <class _Mappedty>
    pair<iterator, bool> insert_or_assign(key_type&& _Keyval, _Mappedty&& _Mapval) {
        const auto _Result = _Insert_or_assign(_STD move(_Keyval), _STD forward<_Mappedty>(_Mapval));
        return {iterator(_Result.first, _Mybase::_Get_scary()), _Result.second};
    }

    template <class _Mappedty>
    iterator insert_or_assign(const const_iterator _Hint, key_type&& _Keyval, _Mappedty&& _Mapval) {
        return iterator(_Insert_or_assign_hint(_Hint._Ptr, _STD move(_Keyval), _STD forward<_Mappedty>(_Mapval)),
            _Mybase::_Get_scary());
    }

    map(initializer_list<value_type> _Ilist) : _Mybase(key_compare()) {
        insert(_Ilist);
    }

    map(initializer_list<value_type> _Ilist, const key_compare& _Pred) : _Mybase(_Pred) {
        insert(_Ilist);
    }

    map(initializer_list<value_type> _Ilist, const allocator_type& _Al) : _Mybase(key_compare(), _Al) {
        insert(_Ilist);
    }

    map(initializer_list<value_type> _Ilist, const key_compare& _Pred, const allocator_type& _Al)
        : _Mybase(_Pred, _Al) {
        insert(_Ilist);
    }

    map& operator=(initializer_list<value_type> _Ilist) {
        _Mybase::clear();
        insert(_Ilist);
        return *this;
    }

    mapped_type& operator[](const key_type& _Keyval) {
        return _Try_emplace(_Keyval).first->_Myval.second;
    }

    _NODISCARD mapped_type& at(const key_type& _Keyval) {
        const auto _Loc = _Mybase::_Find_lower_bound(_Keyval);
        if (!_Mybase::_Lower_bound_duplicate(_Loc._Bound, _Keyval)) {
            _Xout_of_range("invalid map<K, T> key");
        }

        return _Loc._Bound->_Myval.second;
    }

    _NODISCARD const mapped_type& at(const key_type& _Keyval) const {
        const auto _Loc = _Mybase::_Find_lower_bound(_Keyval);
        if (!_Mybase::_Lower_bound_duplicate(_Loc._Bound, _Keyval)) {
            _Xout_of_range("invalid map<K, T> key");
        }

        return _Loc._Bound->_Myval.second;
    }

    using _Mybase::_Unchecked_begin;
    using _Mybase::_Unchecked_end;
};

#if _HAS_CXX17
template <class _Iter, class _Pr = less<_Guide_key_t<_Iter>>, class _Alloc = allocator<_Guide_pair_t<_Iter>>,
    enable_if_t<conjunction_v<_Is_iterator<_Iter>, negation<_Is_allocator<_Pr>>, _Is_allocator<_Alloc>>, int> = 0>
map(_Iter, _Iter, _Pr = _Pr(), _Alloc = _Alloc()) -> map<_Guide_key_t<_Iter>, _Guide_val_t<_Iter>, _Pr, _Alloc>;

template <class _Kty, class _Ty, class _Pr = less<_Kty>, class _Alloc = allocator<pair<const _Kty, _Ty>>,
    enable_if_t<conjunction_v<negation<_Is_allocator<_Pr>>, _Is_allocator<_Alloc>>, int> = 0>
map(initializer_list<pair<_Kty, _Ty>>, _Pr = _Pr(), _Alloc = _Alloc()) -> map<_Kty, _Ty, _Pr, _Alloc>;

template <class _Iter, class _Alloc, enable_if_t<conjunction_v<_Is_iterator<_Iter>, _Is_allocator<_Alloc>>, int> = 0>
map(_Iter, _Iter, _Alloc) -> map<_Guide_key_t<_Iter>, _Guide_val_t<_Iter>, less<_Guide_key_t<_Iter>>, _Alloc>;

template <class _Kty, class _Ty, class _Alloc, enable_if_t<_Is_allocator<_Alloc>::value, int> = 0>
map(initializer_list<pair<_Kty, _Ty>>, _Alloc) -> map<_Kty, _Ty, less<_Kty>, _Alloc>;
#endif // _HAS_CXX17

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator==(const map<_Kty, _Ty, _Pr, _Alloc>& _Left, const map<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _Left.size() == _Right.size()
        && _STD equal(_Left._Unchecked_begin(), _Left._Unchecked_end_iter(), _Right._Unchecked_begin());
}

#if !_HAS_CXX20
template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator!=(const map<_Kty, _Ty, _Pr, _Alloc>& _Left, const map<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return !(_Left == _Right);
}
#endif // !_HAS_CXX20

#ifdef __cpp_lib_concepts
template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD _Synth_three_way_result<pair<const _Kty, _Ty>> operator<=>(
    const map<_Kty, _Ty, _Pr, _Alloc>& _Left, const map<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _STD lexicographical_compare_three_way(_Left._Unchecked_begin(), _Left._Unchecked_end_iter(),
        _Right._Unchecked_begin(), _Right._Unchecked_end_iter(), _Synth_three_way{});
}
#else // ^^^ defined(__cpp_lib_concepts) / !defined(__cpp_lib_concepts) vvv
template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator<(const map<_Kty, _Ty, _Pr, _Alloc>& _Left, const map<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _STD lexicographical_compare(
        _Left._Unchecked_begin(), _Left._Unchecked_end_iter(), _Right._Unchecked_begin(), _Right._Unchecked_end_iter());
}

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator>(const map<_Kty, _Ty, _Pr, _Alloc>& _Left, const map<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _Right < _Left;
}

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator<=(const map<_Kty, _Ty, _Pr, _Alloc>& _Left, const map<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return !(_Right < _Left);
}

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator>=(const map<_Kty, _Ty, _Pr, _Alloc>& _Left, const map<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return !(_Left < _Right);
}
#endif // ^^^ !defined(__cpp_lib_concepts) ^^^

template <class _Kty, class _Ty, class _Pr, class _Alloc>
void swap(map<_Kty, _Ty, _Pr, _Alloc>& _Left, map<_Kty, _Ty, _Pr, _Alloc>& _Right) noexcept(
    noexcept(_Left.swap(_Right))) {
    _Left.swap(_Right);
}

#if _HAS_CXX20
template <class _Kty, class _Ty, class _Keylt, class _Alloc, class _Pr>
typename map<_Kty, _Ty, _Keylt, _Alloc>::size_type erase_if(map<_Kty, _Ty, _Keylt, _Alloc>& _Cont, _Pr _Pred) {
    return _Erase_nodes_if(_Cont, _Pass_fn(_Pred));
}
#endif // _HAS_CXX20

template <class _Kty, class _Ty, class _Pr = less<_Kty>, class _Alloc = allocator<pair<const _Kty, _Ty>>>
class multimap : public _Tree<_Tmap_traits<_Kty, _Ty, _Pr, _Alloc, true>> {
    // ordered red-black tree of {key, mapped} values, non-unique keys
public:
    static_assert(!_ENFORCE_MATCHING_ALLOCATORS || is_same_v<pair<const _Kty, _Ty>, typename _Alloc::value_type>,
        _MISMATCHED_ALLOCATOR_MESSAGE("multimap<Key, Value, Compare, Allocator>", "pair<const Key, Value>"));

    using _Mybase                = _Tree<_Tmap_traits<_Kty, _Ty, _Pr, _Alloc, true>>;
    using key_type               = _Kty;
    using mapped_type            = _Ty;
    using key_compare            = _Pr;
    using value_compare          = typename _Mybase::value_compare;
    using value_type             = pair<const _Kty, _Ty>;
    using allocator_type         = typename _Mybase::allocator_type;
    using size_type              = typename _Mybase::size_type;
    using difference_type        = typename _Mybase::difference_type;
    using pointer                = typename _Mybase::pointer;
    using const_pointer          = typename _Mybase::const_pointer;
    using reference              = value_type&;
    using const_reference        = const value_type&;
    using iterator               = typename _Mybase::iterator;
    using const_iterator         = typename _Mybase::const_iterator;
    using reverse_iterator       = typename _Mybase::reverse_iterator;
    using const_reverse_iterator = typename _Mybase::const_reverse_iterator;

    using _Alnode        = typename _Mybase::_Alnode;
    using _Alnode_traits = typename _Mybase::_Alnode_traits;

    multimap() : _Mybase(key_compare()) {}

    explicit multimap(const allocator_type& _Al) : _Mybase(key_compare(), _Al) {}

    multimap(const multimap& _Right)
        : _Mybase(_Right, _Alnode_traits::select_on_container_copy_construction(_Right._Getal())) {}

    multimap(const multimap& _Right, const allocator_type& _Al) : _Mybase(_Right, _Al) {}

    explicit multimap(const key_compare& _Pred) : _Mybase(_Pred) {}

    multimap(const key_compare& _Pred, const allocator_type& _Al) : _Mybase(_Pred, _Al) {}

    template <class _Iter>
    multimap(_Iter _First, _Iter _Last) : _Mybase(key_compare()) {
        insert(_First, _Last);
    }

    template <class _Iter>
    multimap(_Iter _First, _Iter _Last, const key_compare& _Pred) : _Mybase(_Pred) {
        insert(_First, _Last);
    }

    template <class _Iter>
    multimap(_Iter _First, _Iter _Last, const allocator_type& _Al) : _Mybase(key_compare(), _Al) {
        insert(_First, _Last);
    }

    template <class _Iter>
    multimap(_Iter _First, _Iter _Last, const key_compare& _Pred, const allocator_type& _Al) : _Mybase(_Pred, _Al) {
        insert(_First, _Last);
    }

    multimap& operator=(const multimap& _Right) {
        _Mybase::operator=(_Right);
        return *this;
    }

    multimap(multimap&& _Right) : _Mybase(_STD move(_Right)) {}

    multimap(multimap&& _Right, const allocator_type& _Al) : _Mybase(_STD move(_Right), _Al) {}

    multimap& operator=(multimap&& _Right) noexcept(
        _Alnode_traits::is_always_equal::value&& is_nothrow_move_assignable_v<_Pr>) {
        _Mybase::operator=(_STD move(_Right));
        return *this;
    }

    template <class... _Valty>
    iterator emplace(_Valty&&... _Val) {
        return _Mybase::emplace(_STD forward<_Valty>(_Val)...).first;
    }

    void swap(multimap& _Right) noexcept(noexcept(_Mybase::swap(_Right))) {
        _Mybase::swap(_Right);
    }

    using _Mybase::insert;

    template <class _Valty, enable_if_t<is_constructible_v<value_type, _Valty>, int> = 0>
    iterator insert(_Valty&& _Val) {
        return this->emplace(_STD forward<_Valty>(_Val));
    }

    template <class _Valty, enable_if_t<is_constructible_v<value_type, _Valty>, int> = 0>
    iterator insert(const_iterator _Where, _Valty&& _Val) {
        return this->emplace_hint(_Where, _STD forward<_Valty>(_Val));
    }

    multimap(initializer_list<value_type> _Ilist) : _Mybase(key_compare()) {
        insert(_Ilist);
    }

    multimap(initializer_list<value_type> _Ilist, const key_compare& _Pred) : _Mybase(_Pred) {
        insert(_Ilist);
    }

    multimap(initializer_list<value_type> _Ilist, const allocator_type& _Al) : _Mybase(key_compare(), _Al) {
        insert(_Ilist);
    }

    multimap(initializer_list<value_type> _Ilist, const key_compare& _Pred, const allocator_type& _Al)
        : _Mybase(_Pred, _Al) {
        insert(_Ilist);
    }

    multimap& operator=(initializer_list<value_type> _Ilist) {
        _Mybase::clear();
        insert(_Ilist);
        return *this;
    }

    using _Mybase::_Unchecked_begin;
    using _Mybase::_Unchecked_end;
};

#if _HAS_CXX17
template <class _Iter, class _Pr = less<_Guide_key_t<_Iter>>, class _Alloc = allocator<_Guide_pair_t<_Iter>>,
    enable_if_t<conjunction_v<_Is_iterator<_Iter>, negation<_Is_allocator<_Pr>>, _Is_allocator<_Alloc>>, int> = 0>
multimap(_Iter, _Iter, _Pr = _Pr(), _Alloc = _Alloc())
    -> multimap<_Guide_key_t<_Iter>, _Guide_val_t<_Iter>, _Pr, _Alloc>;

template <class _Kty, class _Ty, class _Pr = less<_Kty>, class _Alloc = allocator<pair<const _Kty, _Ty>>,
    enable_if_t<conjunction_v<negation<_Is_allocator<_Pr>>, _Is_allocator<_Alloc>>, int> = 0>
multimap(initializer_list<pair<_Kty, _Ty>>, _Pr = _Pr(), _Alloc = _Alloc()) -> multimap<_Kty, _Ty, _Pr, _Alloc>;

template <class _Iter, class _Alloc, enable_if_t<conjunction_v<_Is_iterator<_Iter>, _Is_allocator<_Alloc>>, int> = 0>
multimap(_Iter, _Iter, _Alloc) -> multimap<_Guide_key_t<_Iter>, _Guide_val_t<_Iter>, less<_Guide_key_t<_Iter>>, _Alloc>;

template <class _Kty, class _Ty, class _Alloc, enable_if_t<_Is_allocator<_Alloc>::value, int> = 0>
multimap(initializer_list<pair<_Kty, _Ty>>, _Alloc) -> multimap<_Kty, _Ty, less<_Kty>, _Alloc>;
#endif // _HAS_CXX17

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator==(
    const multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, const multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _Left.size() == _Right.size()
        && _STD equal(_Left._Unchecked_begin(), _Left._Unchecked_end_iter(), _Right._Unchecked_begin());
}

#if !_HAS_CXX20
template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator!=(
    const multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, const multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return !(_Left == _Right);
}
#endif // !_HAS_CXX20

#ifdef __cpp_lib_concepts
template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD _Synth_three_way_result<pair<const _Kty, _Ty>> operator<=>(
    const multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, const multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _STD lexicographical_compare_three_way(_Left._Unchecked_begin(), _Left._Unchecked_end_iter(),
        _Right._Unchecked_begin(), _Right._Unchecked_end_iter(), _Synth_three_way{});
}
#else // ^^^ defined(__cpp_lib_concepts) / !defined(__cpp_lib_concepts) vvv
template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator<(
    const multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, const multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _STD lexicographical_compare(
        _Left._Unchecked_begin(), _Left._Unchecked_end_iter(), _Right._Unchecked_begin(), _Right._Unchecked_end_iter());
}

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator>(
    const multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, const multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return _Right < _Left;
}

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator<=(
    const multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, const multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return !(_Right < _Left);
}

template <class _Kty, class _Ty, class _Pr, class _Alloc>
_NODISCARD bool operator>=(
    const multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, const multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) {
    return !(_Left < _Right);
}
#endif // ^^^ !defined(__cpp_lib_concepts) ^^^

template <class _Kty, class _Ty, class _Pr, class _Alloc>
void swap(multimap<_Kty, _Ty, _Pr, _Alloc>& _Left, multimap<_Kty, _Ty, _Pr, _Alloc>& _Right) noexcept(
    noexcept(_Left.swap(_Right))) {
    _Left.swap(_Right);
}

#if _HAS_CXX20
template <class _Kty, class _Ty, class _Keylt, class _Alloc, class _Pr>
typename multimap<_Kty, _Ty, _Keylt, _Alloc>::size_type erase_if(
    multimap<_Kty, _Ty, _Keylt, _Alloc>& _Cont, _Pr _Pred) {
    return _Erase_nodes_if(_Cont, _Pass_fn(_Pred));
}
#endif // _HAS_CXX20

#if _HAS_CXX17
namespace pmr {
    template <class _Kty, class _Ty, class _Pr = less<_Kty>>
    using map = _STD map<_Kty, _Ty, _Pr, polymorphic_allocator<pair<const _Kty, _Ty>>>;

    template <class _Kty, class _Ty, class _Pr = less<_Kty>>
    using multimap = _STD multimap<_Kty, _Ty, _Pr, polymorphic_allocator<pair<const _Kty, _Ty>>>;
} // namespace pmr
#endif // _HAS_CXX17
_STD_END
#pragma pop_macro("new")
_STL_RESTORE_CLANG_WARNINGS
#pragma warning(pop)
#pragma pack(pop)
#endif // _STL_COMPILER_PREPROCESSOR
#endif // _MAP_