set.h

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/**********************************************************\
 
  This file is part of the
  https://github.com/morzhovets/momo
  project, distributed under the MIT License. See
  https://github.com/morzhovets/momo/blob/branch_cpp11/LICENSE
  for details.
 
  momo/stdish/set.h
 
  namespace momo::stdish:
    class set_adaptor
    class multiset_adaptor
    class set
    class multiset
 
\**********************************************************/
 
#ifndef MOMO_INCLUDE_GUARD_STDISH_SET
#define MOMO_INCLUDE_GUARD_STDISH_SET
 
#include "set_map_utility.h"
#include MOMO_PARENT_HEADER(TreeSet)
 
namespace momo
{
 
namespace stdish
{
 
template<typename TTreeSet>
class set_adaptor
{
private:
    typedef TTreeSet TreeSet;
    typedef typename TreeSet::TreeTraits TreeTraits;
    typedef typename TreeSet::MemManager MemManager;
 
public:
    typedef typename TreeSet::Key key_type;
    typedef typename TreeTraits::LessComparer key_compare;
 
    typedef TreeSet nested_container_type;
 
    typedef size_t size_type;
    typedef ptrdiff_t difference_type;
 
    typedef key_type value_type;
    typedef key_compare value_compare;
    typedef typename std::allocator_traits<typename MemManager::ByteAllocator>
        ::template rebind_alloc<value_type> allocator_type;
 
    typedef typename TreeSet::ConstIterator const_iterator;
    typedef typename TreeSet::Iterator iterator;
 
    //typedef typename iterator::Reference reference;
    typedef value_type& reference;
    typedef typename const_iterator::Reference const_reference;
 
    //typedef typename iterator::Pointer pointer;
    typedef value_type* pointer;
    typedef typename const_iterator::Pointer const_pointer;
    //typedef typename std::allocator_traits<allocator_type>::pointer pointer;
    //typedef typename std::allocator_traits<allocator_type>::const_pointer const_pointer;
 
    typedef std::reverse_iterator<iterator> reverse_iterator;
    typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
 
    typedef internal::set_node_handle<typename TreeSet::ExtractedItem> node_type;
    typedef internal::insert_return_type<iterator, node_type> insert_return_type;
 
private:
    template<typename KeyArg>
    struct IsValidKeyArg : public TreeTraits::template IsValidKeyArg<KeyArg>
    {
    };
 
    struct NodeTypeProxy : private node_type
    {
        typedef node_type NodeType;
        MOMO_DECLARE_PROXY_FUNCTION(NodeType, GetExtractedItem)
    };
 
public:
    set_adaptor()
    {
    }
 
    explicit set_adaptor(const allocator_type& alloc)
        : mTreeSet(TreeTraits(), MemManager(alloc))
    {
    }
 
    explicit set_adaptor(const key_compare& lessComp, const allocator_type& alloc = allocator_type())
        : mTreeSet(TreeTraits(lessComp), MemManager(alloc))
    {
    }
 
    template<typename Iterator>
    set_adaptor(Iterator first, Iterator last, const allocator_type& alloc = allocator_type())
        : set_adaptor(alloc)
    {
        insert(first, last);
    }
 
    template<typename Iterator>
    set_adaptor(Iterator first, Iterator last, const key_compare& lessComp,
        const allocator_type& alloc = allocator_type())
        : set_adaptor(lessComp, alloc)
    {
        insert(first, last);
    }
 
    set_adaptor(std::initializer_list<value_type> values,
        const allocator_type& alloc = allocator_type())
        : mTreeSet(values, TreeTraits(), MemManager(alloc))
    {
    }
 
    set_adaptor(std::initializer_list<value_type> values,
        const key_compare& lessComp, const allocator_type& alloc = allocator_type())
        : mTreeSet(values, TreeTraits(lessComp), MemManager(alloc))
    {
    }
 
#ifdef MOMO_HAS_CONTAINERS_RANGES
    template<std::ranges::input_range Range>
    requires std::convertible_to<std::ranges::range_reference_t<Range>, value_type>
    set_adaptor(std::from_range_t, Range&& values, const allocator_type& alloc = allocator_type())
        : set_adaptor(alloc)
    {
        insert_range(std::forward<Range>(values));
    }
 
    template<std::ranges::input_range Range>
    requires std::convertible_to<std::ranges::range_reference_t<Range>, value_type>
    set_adaptor(std::from_range_t, Range&& values, const key_compare& lessComp,
        const allocator_type& alloc = allocator_type())
        : set_adaptor(lessComp, alloc)
    {
        insert_range(std::forward<Range>(values));
    }
#endif // MOMO_HAS_CONTAINERS_RANGES
 
    set_adaptor(set_adaptor&& right)
        : set_adaptor(std::move(right), right.get_allocator())
    {
    }
 
    set_adaptor(set_adaptor&& right, const allocator_type& alloc)
        : mTreeSet(right.mTreeSet.GetTreeTraits(), MemManager(alloc))
    {
        if (right.get_allocator() == alloc)
        {
            mTreeSet.Swap(right.mTreeSet);
        }
        else
        {
            mTreeSet.MergeFrom(right.mTreeSet);
            right.clear();
        }
    }
 
    set_adaptor(const set_adaptor& right)
        : mTreeSet(right.mTreeSet)
    {
    }
 
    set_adaptor(const set_adaptor& right, const allocator_type& alloc)
        : mTreeSet(right.mTreeSet, MemManager(alloc))
    {
    }
 
    ~set_adaptor() = default;
 
    set_adaptor& operator=(set_adaptor&& right)
        noexcept(momo::internal::ContainerAssignerStd::IsNothrowMoveAssignable<set_adaptor>::value)
    {
        return momo::internal::ContainerAssignerStd::Move(std::move(right), *this);
    }
 
    set_adaptor& operator=(const set_adaptor& right)
    {
        return momo::internal::ContainerAssignerStd::Copy(right, *this);
    }
 
    set_adaptor& operator=(std::initializer_list<value_type> values)
    {
        mTreeSet = TreeSet(values, mTreeSet.GetTreeTraits(), MemManager(get_allocator()));
        return *this;
    }
 
    void swap(set_adaptor& right) noexcept
    {
        momo::internal::ContainerAssignerStd::Swap(*this, right);
    }
 
    friend void swap(set_adaptor& left, set_adaptor& right) noexcept
    {
        left.swap(right);
    }
 
    const nested_container_type& get_nested_container() const noexcept
    {
        return mTreeSet;
    }
 
    nested_container_type& get_nested_container() noexcept
    {
        return mTreeSet;
    }
 
    const_iterator begin() const noexcept
    {
        return mTreeSet.GetBegin();
    }
 
    //iterator begin() noexcept
 
    const_iterator end() const noexcept
    {
        return mTreeSet.GetEnd();
    }
 
    //iterator end() noexcept
 
    const_reverse_iterator rbegin() const noexcept
    {
        return const_reverse_iterator(end());
    }
 
    //reverse_iterator rbegin() noexcept
 
    const_reverse_iterator rend() const noexcept
    {
        return const_reverse_iterator(begin());
    }
 
    //reverse_iterator rend() noexcept
 
    const_iterator cbegin() const noexcept
    {
        return begin();
    }
 
    const_iterator cend() const noexcept
    {
        return end();
    }
 
    const_reverse_iterator crbegin() const noexcept
    {
        return rbegin();
    }
 
    const_reverse_iterator crend() const noexcept
    {
        return rend();
    }
 
    key_compare key_comp() const
    {
        return mTreeSet.GetTreeTraits().GetLessComparer();
    }
 
    value_compare value_comp() const
    {
        return key_comp();
    }
 
    allocator_type get_allocator() const noexcept
    {
        return allocator_type(mTreeSet.GetMemManager().GetByteAllocator());
    }
 
    size_type max_size() const noexcept
    {
        return std::allocator_traits<allocator_type>::max_size(get_allocator());
    }
 
    size_type size() const noexcept
    {
        return mTreeSet.GetCount();
    }
 
    MOMO_NODISCARD bool empty() const noexcept
    {
        return mTreeSet.IsEmpty();
    }
 
    void clear() noexcept
    {
        mTreeSet.Clear();
    }
 
    const_iterator find(const key_type& key) const
    {
        return mTreeSet.Find(key);
    }
 
    //iterator find(const key_type& key)
 
    template<typename KeyArg>
    momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    const_iterator> find(const KeyArg& key) const
    {
        return mTreeSet.Find(key);
    }
 
    //template<typename KeyArg>
    //momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    //iterator> find(const KeyArg& key)
 
    size_type count(const key_type& key) const
    {
        return mTreeSet.GetKeyCount(key);
    }
 
    template<typename KeyArg>
    momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    size_type> count(const KeyArg& key) const
    {
        return mTreeSet.GetKeyCount(key);
    }
 
    bool contains(const key_type& key) const
    {
        return mTreeSet.ContainsKey(key);
    }
 
    template<typename KeyArg>
    momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    bool> contains(const KeyArg& key) const
    {
        return mTreeSet.ContainsKey(key);
    }
 
    const_iterator lower_bound(const key_type& key) const
    {
        return mTreeSet.GetLowerBound(key);
    }
 
    //iterator lower_bound(const key_type& key)
 
    template<typename KeyArg>
    momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    const_iterator> lower_bound(const KeyArg& key) const
    {
        return mTreeSet.GetLowerBound(key);
    }
 
    //template<typename KeyArg>
    //momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    //iterator> lower_bound(const KeyArg& key)
 
    const_iterator upper_bound(const key_type& key) const
    {
        return mTreeSet.GetUpperBound(key);
    }
 
    //iterator upper_bound(const key_type& key)
 
    template<typename KeyArg>
    momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    const_iterator> upper_bound(const KeyArg& key) const
    {
        return mTreeSet.GetUpperBound(key);
    }
 
    //template<typename KeyArg>
    //momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    //iterator> upper_bound(const KeyArg& key)
 
    std::pair<const_iterator, const_iterator> equal_range(const key_type& key) const
    {
        const_iterator iter = lower_bound(key);
        if MOMO_CONSTEXPR_IF (TreeTraits::multiKey)
        {
            return { iter, upper_bound(key) };
        }
        else
        {
            if (iter == end() || mTreeSet.GetTreeTraits().IsLess(key, *iter))
                return { iter, iter };
            return { iter, std::next(iter) };
        }
    }
 
    //std::pair<iterator, iterator> equal_range(const key_type& key)
 
    template<typename KeyArg>
    momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    std::pair<const_iterator, const_iterator>> equal_range(const KeyArg& key) const
    {
        return { lower_bound(key), upper_bound(key) };
    }
 
    //template<typename KeyArg>
    //momo::internal::EnableIf<IsValidKeyArg<KeyArg>::value,
    //std::pair<iterator, iterator>> equal_range(const KeyArg& key)
 
    std::pair<iterator, bool> insert(value_type&& value)
    {
        typename TreeSet::InsertResult res = mTreeSet.Insert(std::move(value));
        return { res.position, res.inserted };
    }
 
    iterator insert(const_iterator hint, value_type&& value)
    {
        if (!pvCheckHint(hint, static_cast<const key_type&>(value)))
            return insert(std::move(value)).first;
        return mTreeSet.Add(hint, std::move(value));
    }
 
    std::pair<iterator, bool> insert(const value_type& value)
    {
        typename TreeSet::InsertResult res = mTreeSet.Insert(value);
        return { res.position, res.inserted };
    }
 
    iterator insert(const_iterator hint, const value_type& value)
    {
        if (!pvCheckHint(hint, value))
            return insert(value).first;
        return mTreeSet.Add(hint, value);
    }
 
    insert_return_type insert(node_type&& node)
    {
        if (node.empty())
            return { end(), false, node_type() };
        typename TreeSet::InsertResult res = mTreeSet.Insert(
            std::move(NodeTypeProxy::GetExtractedItem(node)));
        return { res.position, res.inserted, res.inserted ? node_type() : std::move(node) };
    }
 
    iterator insert(const_iterator hint, node_type&& node)
    {
        if (node.empty())
            return end();
        if (!pvCheckHint(hint, node.value()))
            return insert(std::move(node)).position;
        return mTreeSet.Add(hint, std::move(NodeTypeProxy::GetExtractedItem(node)));
    }
 
    template<typename Iterator>
    void insert(Iterator first, Iterator last)
    {
        pvInsertRange(first, last);
    }
 
    void insert(std::initializer_list<value_type> values)
    {
        mTreeSet.Insert(values);
    }
 
#ifdef MOMO_HAS_CONTAINERS_RANGES
    template<std::ranges::input_range Range>
    requires std::convertible_to<std::ranges::range_reference_t<Range>, value_type>
    void insert_range(Range&& values)
    {
        pvInsertRange(std::ranges::begin(values), std::ranges::end(values));
    }
#endif // MOMO_HAS_CONTAINERS_RANGES
 
    template<typename... ValueArgs>
    std::pair<iterator, bool> emplace(ValueArgs&&... valueArgs)
    {
        MemManager& memManager = mTreeSet.GetMemManager();
        typename TreeSet::ExtractedItem extItem;
        typedef typename TreeSet::ItemTraits::template Creator<ValueArgs...> ValueCreator;
        extItem.Create(ValueCreator(memManager, std::forward<ValueArgs>(valueArgs)...));
        typename TreeSet::InsertResult res = mTreeSet.Insert(std::move(extItem));
        return { res.position, res.inserted };
    }
 
    template<typename ValueArg>
    momo::internal::EnableIf<std::is_same<key_type, typename std::decay<ValueArg>::type>::value,
    std::pair<iterator, bool>> emplace(ValueArg&& valueArg)
    {
        typename TreeSet::InsertResult res = mTreeSet.InsertVar(
            static_cast<const key_type&>(valueArg), std::forward<ValueArg>(valueArg));
        return { res.position, res.inserted };
    }
 
    template<typename... ValueArgs>
    iterator emplace_hint(const_iterator hint, ValueArgs&&... valueArgs)
    {
        MemManager& memManager = mTreeSet.GetMemManager();
        typename TreeSet::ExtractedItem extItem;
        typedef typename TreeSet::ItemTraits::template Creator<ValueArgs...> ValueCreator;
        extItem.Create(ValueCreator(memManager, std::forward<ValueArgs>(valueArgs)...));
        if (!pvCheckHint(hint, extItem.GetItem()))
            return mTreeSet.Insert(std::move(extItem)).position;
        return mTreeSet.Add(hint, std::move(extItem));
    }
 
    template<typename ValueArg>
    momo::internal::EnableIf<std::is_same<key_type, typename std::decay<ValueArg>::type>::value,
    iterator> emplace_hint(const_iterator hint, ValueArg&& valueArg)
    {
        if (!pvCheckHint(hint, static_cast<const key_type&>(valueArg)))
            return emplace(std::forward<ValueArg>(valueArg)).first;
        return mTreeSet.AddVar(hint, std::forward<ValueArg>(valueArg));
    }
 
    iterator erase(const_iterator where)
    {
        return mTreeSet.Remove(where);
    }
 
    //iterator erase(iterator where)
 
    iterator erase(const_iterator first, const_iterator last)
    {
        return mTreeSet.Remove(first, last);
    }
 
    size_type erase(const key_type& key)
    {
        return mTreeSet.Remove(key);
    }
 
    template<typename ValueFilter>
    friend size_type erase_if(set_adaptor& cont, const ValueFilter& valueFilter)
    {
        return cont.mTreeSet.Remove(valueFilter);
    }
 
    node_type extract(const_iterator where)
    {
        return node_type(*this, where); // need RVO for exception safety
    }
 
    node_type extract(const key_type& key)
    {
        const_iterator iter = find(key);
        return (iter != end()) ? extract(iter) : node_type();
    }
 
    template<typename Set>
    void merge(Set&& set_adaptor)
    {
        mTreeSet.MergeFrom(set_adaptor.get_nested_container());
    }
 
    friend bool operator==(const set_adaptor& left, const set_adaptor& right)
    {
        return left.size() == right.size() && std::equal(left.begin(), left.end(), right.begin());
    }
 
#ifdef MOMO_HAS_THREE_WAY_COMPARISON
    friend auto operator<=>(const set_adaptor& left, const set_adaptor& right)
        requires requires (const_reference ref) { std::tie(ref) <=> std::tie(ref); }
    {
        auto valueThreeComp = [] (const value_type& value1, const value_type& value2)
            { return std::tie(value1) <=> std::tie(value2); };
        return std::lexicographical_compare_three_way(left.begin(), left.end(),
            right.begin(), right.end(), valueThreeComp);
    }
#else
    friend bool operator<(const set_adaptor& left, const set_adaptor& right)
    {
        return std::lexicographical_compare(left.begin(), left.end(), right.begin(), right.end());
    }
#endif
 
    MOMO_MORE_COMPARISON_OPERATORS(const set_adaptor&)
 
private:
    bool pvIsOrdered(const key_type& key1, const key_type& key2) const
    {
        const TreeTraits& treeTraits = mTreeSet.GetTreeTraits();
        return TreeTraits::multiKey ? !treeTraits.IsLess(key2, key1)
            : treeTraits.IsLess(key1, key2);
    }
 
    bool pvCheckHint(const_iterator& hint, const key_type& key) const
    {
        if (hint != begin() && !pvIsOrdered(*std::prev(hint), key))
            return false;
        if (hint != end() && !pvIsOrdered(key, *hint))
        {
            if MOMO_CONSTEXPR_IF (TreeTraits::multiKey)
                hint = lower_bound(key);
            return TreeTraits::multiKey;
        }
        return true;
    }
 
    template<typename Iterator, typename Sentinel>
    momo::internal::EnableIf<momo::internal::IsSetArgIterator<Iterator, value_type>::value,
    void> pvInsertRange(Iterator begin, Sentinel end)
    {
        mTreeSet.Insert(std::move(begin), std::move(end));
    }
 
    template<typename Iterator, typename Sentinel>
    momo::internal::EnableIf<!momo::internal::IsSetArgIterator<Iterator, value_type>::value,
    void> pvInsertRange(Iterator begin, Sentinel end)
    {
        for (Iterator iter = std::move(begin); iter != end; ++iter)
            emplace(*iter);
    }
 
private:
    TreeSet mTreeSet;
};
 
template<typename TTreeSet>
class multiset_adaptor : public set_adaptor<TTreeSet>
{
private:
    typedef set_adaptor<TTreeSet> SetAdaptor;
 
public:
    using typename SetAdaptor::value_type;
    using typename SetAdaptor::iterator;
    using typename SetAdaptor::node_type;
 
    typedef iterator insert_return_type;
 
public:
    using SetAdaptor::SetAdaptor;
 
    multiset_adaptor& operator=(std::initializer_list<value_type> values)
    {
        SetAdaptor::operator=(values);
        return *this;
    }
 
    friend void swap(multiset_adaptor& left, multiset_adaptor& right) noexcept
    {
        left.swap(right);
    }
 
    using SetAdaptor::insert;
 
    iterator insert(value_type&& value)
    {
        return SetAdaptor::insert(std::move(value)).first;
    }
 
    iterator insert(const value_type& value)
    {
        return SetAdaptor::insert(value).first;
    }
 
    iterator insert(node_type&& node)
    {
        return SetAdaptor::insert(std::move(node)).position;
    }
 
    template<typename... ValueArgs>
    iterator emplace(ValueArgs&&... valueArgs)
    {
        return SetAdaptor::emplace(std::forward<ValueArgs>(valueArgs)...).first;
    }
};
 
template<typename TKey,
    typename TLessComparer = std::less<TKey>,
    typename TAllocator = std::allocator<TKey>>
class set : public set_adaptor<TreeSet<TKey,
    TreeTraitsStd<TKey, TLessComparer>, MemManagerStd<TAllocator>>>
{
private:
    typedef set_adaptor<momo::TreeSet<TKey,
        TreeTraitsStd<TKey, TLessComparer>, MemManagerStd<TAllocator>>> SetAdaptor;
 
public:
    using SetAdaptor::SetAdaptor;
 
    set& operator=(std::initializer_list<typename SetAdaptor::value_type> values)
    {
        SetAdaptor::operator=(values);
        return *this;
    }
 
    friend void swap(set& left, set& right) noexcept
    {
        left.swap(right);
    }
};
 
template<typename TKey,
    typename TLessComparer = std::less<TKey>,
    typename TAllocator = std::allocator<TKey>>
class multiset : public multiset_adaptor<TreeSet<TKey,
    TreeTraitsStd<TKey, TLessComparer, true>, MemManagerStd<TAllocator>>>
{
private:
    typedef multiset_adaptor<momo::TreeSet<TKey,
        TreeTraitsStd<TKey, TLessComparer, true>, MemManagerStd<TAllocator>>> MultiSetAdaptor;
 
public:
    using MultiSetAdaptor::MultiSetAdaptor;
 
    multiset& operator=(std::initializer_list<typename MultiSetAdaptor::value_type> values)
    {
        MultiSetAdaptor::operator=(values);
        return *this;
    }
 
    friend void swap(multiset& left, multiset& right) noexcept
    {
        left.swap(right);
    }
};
 
#ifdef MOMO_HAS_DEDUCTION_GUIDES
 
#define MOMO_DECLARE_DEDUCTION_GUIDES(set) \
template<typename Iterator, \
    typename Key = typename std::iterator_traits<Iterator>::value_type, \
    typename Allocator = std::allocator<Key>, \
    typename = internal::tree_checker<Key, Allocator>> \
set(Iterator, Iterator, Allocator = Allocator()) \
    -> set<Key, std::less<Key>, Allocator>; \
template<typename Iterator, typename LessComparer, \
    typename Key = typename std::iterator_traits<Iterator>::value_type, \
    typename Allocator = std::allocator<Key>, \
    typename = internal::tree_checker<Key, Allocator, LessComparer>> \
set(Iterator, Iterator, LessComparer, Allocator = Allocator()) \
    -> set<Key, LessComparer, Allocator>; \
template<typename Key, \
    typename Allocator = std::allocator<Key>, \
    typename = internal::tree_checker<Key, Allocator>> \
set(std::initializer_list<Key>, Allocator = Allocator()) \
    -> set<Key, std::less<Key>, Allocator>; \
template<typename Key, typename LessComparer, \
    typename Allocator = std::allocator<Key>, \
    typename = internal::tree_checker<Key, Allocator, LessComparer>> \
set(std::initializer_list<Key>, LessComparer, Allocator = Allocator()) \
    -> set<Key, LessComparer, Allocator>; \
template<typename Key, typename LessComparer, typename Allocator> \
set(set<Key, LessComparer, Allocator>, momo::internal::Identity<Allocator>) \
    -> set<Key, LessComparer, Allocator>;
 
MOMO_DECLARE_DEDUCTION_GUIDES(set)
MOMO_DECLARE_DEDUCTION_GUIDES(multiset)
 
#undef MOMO_DECLARE_DEDUCTION_GUIDES
 
#ifdef MOMO_HAS_CONTAINERS_RANGES
 
#define MOMO_DECLARE_DEDUCTION_GUIDES_RANGES(set) \
template<std::ranges::input_range Range, \
    typename Key = std::ranges::range_value_t<Range>, \
    typename Allocator = std::allocator<Key>, \
    typename = internal::tree_checker<Key, Allocator>> \
set(std::from_range_t, Range&&, Allocator = Allocator()) \
    -> set<Key, std::less<Key>, Allocator>; \
template<std::ranges::input_range Range, typename LessComparer, \
    typename Key = std::ranges::range_value_t<Range>, \
    typename Allocator = std::allocator<Key>, \
    typename = internal::tree_checker<Key, Allocator, LessComparer>> \
set(std::from_range_t, Range&&, LessComparer, Allocator = Allocator()) \
    -> set<Key, LessComparer, Allocator>;
 
MOMO_DECLARE_DEDUCTION_GUIDES_RANGES(set)
MOMO_DECLARE_DEDUCTION_GUIDES_RANGES(multiset)
 
#undef MOMO_DECLARE_DEDUCTION_GUIDES_RANGES
 
#endif // MOMO_HAS_CONTAINERS_RANGES
 
#endif // MOMO_HAS_DEDUCTION_GUIDES
 
} // namespace stdish
 
} // namespace momo
 
#endif // MOMO_INCLUDE_GUARD_STDISH_SET