typename Key

is the key_type of the map

typename T

typename Compare = std::less<Key>

is the ordering function for Keys (e.g. std::less<Key>).

typename Allocator = new_allocator< std::pair< const Key, T> >

is the allocator to allocate the value_types (e.g. allocator< std::pair<const Key, T> > ).

typename Options = tree_assoc_defaults

is an packed option type generated using using boost::container::tree_assoc_options.

multimap() noexcept(dtl::is_nothrow_default_constructible< allocator_type >::value &&dtl::is_nothrow_default_constructible< Compare >::value));

Effects: Default constructs an empty multimap.

Complexity: Constant.

explicit multimap(const allocator_type & a);

Effects: Constructs an empty multimap using the specified allocator object and allocator.

Complexity: Constant.

explicit multimap(const Compare & comp);

Effects: Constructs an empty multimap using the specified comparison.

Complexity: Constant.

multimap(const Compare & comp, const allocator_type & a);

Effects: Constructs an empty multimap using the specified comparison and allocator.

Complexity: Constant.

template<typename InputIterator> 
  multimap(InputIterator first, InputIterator last);

Effects: Constructs an empty multimap and inserts elements from the range [first ,last ).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is last - first.

template<typename InputIterator> 
  multimap(InputIterator first, InputIterator last, const allocator_type & a);

Effects: Constructs an empty multimap using the specified allocator, and inserts elements from the range [first ,last ).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is last - first.

template<typename InputIterator> 
  multimap(InputIterator first, InputIterator last, const Compare & comp);

Effects: Constructs an empty multimap using the specified comparison object and inserts elements from the range [first ,last ).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is last - first.

template<typename InputIterator> 
  multimap(InputIterator first, InputIterator last, const Compare & comp, 
           const allocator_type & a);

Effects: Constructs an empty multimap using the specified comparison object and allocator, and inserts elements from the range [first ,last ).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is last - first.

template<typename InputIterator> 
  multimap(ordered_range_t, InputIterator first, InputIterator last);

Effects: Constructs an empty multimap and inserts elements from the ordered range [first ,last). This function is more efficient than the normal range creation for ordered ranges.

Requires: [first ,last) must be ordered according to the predicate.

Complexity: Linear in N.

Note: Non-standard extension.

template<typename InputIterator> 
  multimap(ordered_range_t, InputIterator first, InputIterator last, 
           const Compare & comp);

Effects: Constructs an empty multimap using the specified comparison object and inserts elements from the ordered range [first ,last). This function is more efficient than the normal range creation for ordered ranges.

Requires: [first ,last) must be ordered according to the predicate.

Complexity: Linear in N.

Note: Non-standard extension.

template<typename InputIterator> 
  multimap(ordered_range_t, InputIterator first, InputIterator last, 
           const Compare & comp, const allocator_type & a);

Effects: Constructs an empty multimap using the specified comparison object and allocator, and inserts elements from the ordered range [first ,last). This function is more efficient than the normal range creation for ordered ranges.

Requires: [first ,last) must be ordered according to the predicate.

Complexity: Linear in N.

Note: Non-standard extension.

template<typename InputIterator> 
  multimap(ordered_range_t, InputIterator first, InputIterator last, 
           const allocator_type & a);

Effects: Constructs an empty multimap using the specified allocator and inserts elements from the ordered range [first ,last). This function is more efficient than the normal range creation for ordered ranges.

Requires: [first ,last) must be ordered according to the predicate.

Complexity: Linear in N.

Note: Non-standard extension.

multimap(std::initializer_list< value_type > il);

Effects: Constructs an empty multimap and and inserts elements from the range [il.begin(), il.end()).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is il.first() - il.end().

multimap(std::initializer_list< value_type > il, const allocator_type & a);

Effects: Constructs an empty multimap using the specified allocator, and inserts elements from the range [il.begin(), il.end()).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is il.first() - il.end().

multimap(std::initializer_list< value_type > il, const Compare & comp);

Effects: Constructs an empty multimap using the specified comparison object and inserts elements from the range [il.begin(), il.end()).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is il.first() - il.end().

multimap(std::initializer_list< value_type > il, const Compare & comp, 
         const allocator_type & a);

Effects: Constructs an empty multimap using the specified comparison object and allocator, and inserts elements from the range [il.begin(), il.end()).

Complexity: Linear in N if the range [first ,last ) is already sorted using the predicate and otherwise N logN, where N is il.first() - il.end().

multimap(ordered_range_t, std::initializer_list< value_type > il);

Effects: Constructs an empty map and inserts elements from the ordered range [il.begin(), il.end()). This function is more efficient than the normal range creation for ordered ranges.

Requires: [il.begin(), il.end()) must be ordered according to the predicate.

Complexity: Linear in N.

Note: Non-standard extension.

multimap(ordered_range_t, std::initializer_list< value_type > il, 
         const Compare & comp);

Effects: Constructs an empty map using the specified comparison object and inserts elements from the ordered range [il.begin(), il.end()). This function is more efficient than the normal range creation for ordered ranges.

Requires: [il.begin(), il.end()) must be ordered according to the predicate.

Complexity: Linear in N.

Note: Non-standard extension.

multimap(ordered_range_t, std::initializer_list< value_type > il, 
         const Compare & comp, const allocator_type & a);

Effects: Constructs an empty map and inserts elements from the ordered range [il.begin(), il.end()). This function is more efficient than the normal range creation for ordered ranges.

Requires: [il.begin(), il.end()) must be ordered according to the predicate.

Complexity: Linear in N.

Note: Non-standard extension.

multimap(const multimap & x);

Effects: Copy constructs a multimap.

Complexity: Linear in x.size().

multimap(multimap && x) noexcept(boost::container::dtl::is_nothrow_move_constructible< Compare >::value));

Effects: Move constructs a multimap. Constructs *this using x's resources.

Complexity: Constant.

Postcondition: x is emptied.

multimap(const multimap & x, const allocator_type & a);

Effects: Copy constructs a multimap.

Complexity: Linear in x.size().

multimap(multimap && x, const allocator_type & a);

Effects: Move constructs a multimap using the specified allocator. Constructs *this using x's resources. Complexity: Constant if a == x.get_allocator(), linear otherwise.

Postcondition: x is emptied.

multimap & operator=(const multimap & x);

Effects: Makes *this a copy of x.

Complexity: Linear in x.size().

multimap & operator=(multimap && x) noexcept((allocator_traits_type::propagate_on_container_move_assignment::value||allocator_traits_type::is_always_equal::value) &&boost::container::dtl::is_nothrow_move_assignable< Compare >::value));

Effects: this->swap(x.get()).

Complexity: Constant.

multimap & operator=(std::initializer_list< value_type > il);

Effects: Assign content of il to *this.

 BOOST_STATIC_ASSERT((dtl::is_same< typename allocator_type::value_type, std::pair< const Key, T > >::value));

allocator_type get_allocator() const;

Effects: Returns a copy of the allocator that was passed to the object's constructor.

Complexity: Constant.

stored_allocator_type & get_stored_allocator();

Effects: Returns a reference to the internal allocator.

Throws: Nothing

Complexity: Constant.

Note: Non-standard extension.

const stored_allocator_type & get_stored_allocator() const;

Effects: Returns a reference to the internal allocator.

Throws: Nothing

Complexity: Constant.

Note: Non-standard extension.

iterator begin();

Effects: Returns an iterator to the first element contained in the container.

Throws: Nothing.

Complexity: Constant

const_iterator begin() const;

Effects: Returns a const_iterator to the first element contained in the container.

Throws: Nothing.

Complexity: Constant.

const_iterator cbegin() const;

Effects: Returns a const_iterator to the first element contained in the container.

Throws: Nothing.

Complexity: Constant.

iterator end() noexcept;

Effects: Returns an iterator to the end of the container.

Throws: Nothing.

Complexity: Constant.

const_iterator end() const noexcept;

Effects: Returns a const_iterator to the end of the container.

Throws: Nothing.

Complexity: Constant.

const_iterator cend() const noexcept;

Effects: Returns a const_iterator to the end of the container.

Throws: Nothing.

Complexity: Constant.

reverse_iterator rbegin() noexcept;

Effects: Returns a reverse_iterator pointing to the beginning of the reversed container.

Throws: Nothing.

Complexity: Constant.

const_reverse_iterator rbegin() const noexcept;

Effects: Returns a const_reverse_iterator pointing to the beginning of the reversed container.

Throws: Nothing.

Complexity: Constant.

const_reverse_iterator crbegin() const noexcept;

Effects: Returns a const_reverse_iterator pointing to the beginning of the reversed container.

Throws: Nothing.

Complexity: Constant.

reverse_iterator rend() noexcept;

Effects: Returns a reverse_iterator pointing to the end of the reversed container.

Throws: Nothing.

Complexity: Constant.

const_reverse_iterator rend() const noexcept;

Effects: Returns a const_reverse_iterator pointing to the end of the reversed container.

Throws: Nothing.

Complexity: Constant.

const_reverse_iterator crend() const noexcept;

Effects: Returns a const_reverse_iterator pointing to the end of the reversed container.

Throws: Nothing.

Complexity: Constant.

bool empty() const;

Effects: Returns true if the container contains no elements.

Throws: Nothing.

Complexity: Constant.

size_type size() const;

Effects: Returns the number of the elements contained in the container.

Throws: Nothing.

Complexity: Constant.

size_type max_size() const;

Effects: Returns the largest possible size of the container.

Throws: Nothing.

Complexity: Constant.

template<class... Args> iterator emplace(Args &&... args);

Effects: Inserts an object of type T constructed with std::forward<Args>(args)... in the container. p is a hint pointing to where the insert should start to search.

Returns: An iterator pointing to the element with key equivalent to the key of x.

Complexity: Logarithmic in general, but amortized constant if t is inserted right before p.

template<class... Args> 
  iterator emplace_hint(const_iterator p, Args &&... args);

Effects: Inserts an object of type T constructed with std::forward<Args>(args)... in the container. p is a hint pointing to where the insert should start to search.

Returns: An iterator pointing to the element with key equivalent to the key of x.

Complexity: Logarithmic in general, but amortized constant if t is inserted right before p.

iterator insert(const value_type & x);

Effects: Inserts x and returns the iterator pointing to the newly inserted element.

Complexity: Logarithmic.

iterator insert(const nonconst_value_type & x);

Effects: Inserts a new value constructed from x and returns the iterator pointing to the newly inserted element.

Complexity: Logarithmic.

iterator insert(nonconst_value_type && x);

Effects: Inserts a new value move-constructed from x and returns the iterator pointing to the newly inserted element.

Complexity: Logarithmic.

iterator insert(movable_value_type && x);

Effects: Inserts a new value move-constructed from x and returns the iterator pointing to the newly inserted element.

Complexity: Logarithmic.

iterator insert(const_iterator p, const value_type & x);

Effects: Inserts a copy of x in the container. p is a hint pointing to where the insert should start to search.

Returns: An iterator pointing to the element with key equivalent to the key of x.

Complexity: Logarithmic in general, but amortized constant if t is inserted right before p.

iterator insert(const_iterator p, const nonconst_value_type & x);

Effects: Inserts a new value constructed from x in the container. p is a hint pointing to where the insert should start to search.

Returns: An iterator pointing to the element with key equivalent to the key of x.

Complexity: Logarithmic in general, but amortized constant if t is inserted right before p.

iterator insert(const_iterator p, nonconst_value_type && x);

Effects: Inserts a new value move constructed from x in the container. p is a hint pointing to where the insert should start to search.

Returns: An iterator pointing to the element with key equivalent to the key of x.

Complexity: Logarithmic in general, but amortized constant if t is inserted right before p.

iterator insert(const_iterator p, movable_value_type && x);

Effects: Inserts a new value move constructed from x in the container. p is a hint pointing to where the insert should start to search.

Returns: An iterator pointing to the element with key equivalent to the key of x.

Complexity: Logarithmic in general, but amortized constant if t is inserted right before p.

template<typename InputIterator> 
  void insert(InputIterator first, InputIterator last);

Requires: first, last are not iterators into *this.

Effects: inserts each element from the range [first,last) .

Complexity: At most N log(size()+N) (N is the distance from first to last)

void insert(std::initializer_list< value_type > il);

Effects: inserts each element from the range [il.begin(), il.end().

Complexity: At most N log(size()+N) (N is the distance from il.begin() to il.end())

iterator insert(node_type && nh);

Requires: nh is empty or this->get_allocator() == nh.get_allocator().

Effects/Returns: If nh is empty, has no effect and returns end(). Otherwise, inserts the element owned by nh and returns an iterator pointing to the newly inserted element. If a range containing elements with keys equivalent to nh.key() exists, the element is inserted at the end of that range. nh is always emptied.

Complexity: Logarithmic

iterator insert(const_iterator hint, node_type && nh);

Effects: Same as insert(node_type && nh) but the element is inserted as close as possible to the position just prior to "hint".

Complexity: logarithmic in general, but amortized constant if the element is inserted right before "hint".

iterator erase(const_iterator p);

Effects: Erases the element pointed to by p.

Returns: Returns an iterator pointing to the element immediately following q prior to the element being erased. If no such element exists, returns end().

Complexity: Amortized constant time

size_type erase(const key_type & x);

Effects: Erases all elements in the container with key equivalent to x.

Returns: Returns the number of erased elements.

Complexity: log(size()) + count(k)

iterator erase(const_iterator first, const_iterator last);

Effects: Erases all the elements in the range [first, last).

Returns: Returns last.

Complexity: log(size())+N where N is the distance from first to last.

node_type extract(const key_type & k);

Effects: Removes the first element in the container with key equivalent to k.

Returns: A node_type owning the element if found, otherwise an empty node_type.

Complexity: log(a.size()).

node_type extract(const_iterator position);

Effects: Removes the element pointed to by "position".

Returns: A node_type owning the element, otherwise an empty node_type.

Complexity: Amortized constant.

template<typename C2> 
  void merge(multimap< Key, T, C2, Allocator, Options > & source);

Requires: this->get_allocator() == source.get_allocator().

Effects: Extracts each element in source and insert it into a using the comparison object of *this.

Postcondition: Pointers and references to the transferred elements of source refer to those same elements but as members of *this. Iterators referring to the transferred elements will continue to refer to their elements, but they now behave as iterators into *this, not into source.

Throws: Nothing unless the comparison object throws.

Complexity: N log(a.size() + N) (N has the value source.size())

template<typename C2> 
  void merge(multimap< Key, T, C2, Allocator, Options > && source);

Requires: this->get_allocator() == source.get_allocator().

Effects: Extracts each element in source and insert it into a using the comparison object of *this.

Postcondition: Pointers and references to the transferred elements of source refer to those same elements but as members of *this. Iterators referring to the transferred elements will continue to refer to their elements, but they now behave as iterators into *this, not into source.

Throws: Nothing unless the comparison object throws.

Complexity: N log(a.size() + N) (N has the value source.size())

template<typename C2> 
  void merge(map< Key, T, C2, Allocator, Options > & source);

Requires: this->get_allocator() == source.get_allocator().

Effects: Extracts each element in source and insert it into a using the comparison object of *this.

Postcondition: Pointers and references to the transferred elements of source refer to those same elements but as members of *this. Iterators referring to the transferred elements will continue to refer to their elements, but they now behave as iterators into *this, not into source.

Throws: Nothing unless the comparison object throws.

Complexity: N log(a.size() + N) (N has the value source.size())

template<typename C2> 
  void merge(map< Key, T, C2, Allocator, Options > && source);

Requires: this->get_allocator() == source.get_allocator().

Effects: Extracts each element in source and insert it into a using the comparison object of *this.

Postcondition: Pointers and references to the transferred elements of source refer to those same elements but as members of *this. Iterators referring to the transferred elements will continue to refer to their elements, but they now behave as iterators into *this, not into source.

Throws: Nothing unless the comparison object throws.

Complexity: N log(a.size() + N) (N has the value source.size())

void swap(multiset & x) noexcept(allocator_traits_type::is_always_equal::value &&boost::container::dtl::is_nothrow_swappable< Compare >::value));

Effects: Swaps the contents of *this and x.

Throws: Nothing.

Complexity: Constant.

void clear() noexcept;

Effects: erase(a.begin(),a.end()).

Postcondition: size() == 0.

Complexity: linear in size().

key_compare key_comp() const;

Effects: Returns the comparison object out of which a was constructed.

Complexity: Constant.

value_compare value_comp() const;

Effects: Returns an object of value_compare constructed out of the comparison object.

Complexity: Constant.

iterator find(const key_type & x);

Returns: An iterator pointing to an element with the key equivalent to x, or end() if such an element is not found.

Complexity: Logarithmic.

const_iterator find(const key_type & x) const;

Returns: A const iterator pointing to an element with the key equivalent to x, or end() if such an element is not found.

Complexity: Logarithmic.

template<typename K> iterator find(const K & x);

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: An iterator pointing to an element with the key equivalent to x, or end() if such an element is not found.

Complexity: Logarithmic.

template<typename K> const_iterator find(const K & x) const;

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: A const_iterator pointing to an element with the key equivalent to x, or end() if such an element is not found.

Complexity: Logarithmic.

size_type count(const key_type & x) const;

Returns: The number of elements with key equivalent to x.

Complexity: log(size())+count(k)

template<typename K> size_type count(const K & x) const;

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: The number of elements with key equivalent to x.

Complexity: log(size())+count(k)

bool contains(const key_type & x) const;

Returns: Returns true if there is an element with key equivalent to key in the container, otherwise false.

Complexity: log(size()).

template<typename K> bool contains(const K & x) const;

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: Returns true if there is an element with key equivalent to key in the container, otherwise false.

Complexity: log(size()).

iterator lower_bound(const key_type & x);

Returns: An iterator pointing to the first element with key not less than k, or a.end() if such an element is not found.

Complexity: Logarithmic

const_iterator lower_bound(const key_type & x) const;

Returns: A const iterator pointing to the first element with key not less than k, or a.end() if such an element is not found.

Complexity: Logarithmic

template<typename K> iterator lower_bound(const K & x);

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: An iterator pointing to the first element with key not less than k, or a.end() if such an element is not found.

Complexity: Logarithmic

template<typename K> const_iterator lower_bound(const K & x) const;

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: A const iterator pointing to the first element with key not less than k, or a.end() if such an element is not found.

Complexity: Logarithmic

iterator upper_bound(const key_type & x);

Returns: An iterator pointing to the first element with key not less than x, or end() if such an element is not found.

Complexity: Logarithmic

const_iterator upper_bound(const key_type & x) const;

Returns: A const iterator pointing to the first element with key not less than x, or end() if such an element is not found.

Complexity: Logarithmic

template<typename K> iterator upper_bound(const K & x);

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: An iterator pointing to the first element with key not less than x, or end() if such an element is not found.

Complexity: Logarithmic

template<typename K> const_iterator upper_bound(const K & x) const;

Requires: This overload is available only if key_compare::is_transparent exists.

Returns: A const iterator pointing to the first element with key not less than x, or end() if such an element is not found.

Complexity: Logarithmic

std::pair< iterator, iterator > equal_range(const key_type & x);

Effects: Equivalent to std::make_pair(this->lower_bound(k), this->upper_bound(k)).

Complexity: Logarithmic

std::pair< const_iterator, const_iterator > 
equal_range(const key_type & x) const;

Effects: Equivalent to std::make_pair(this->lower_bound(k), this->upper_bound(k)).

Complexity: Logarithmic

template<typename K> std::pair< iterator, iterator > equal_range(const K & x);

Requires: This overload is available only if key_compare::is_transparent exists.

Effects: Equivalent to std::make_pair(this->lower_bound(k), this->upper_bound(k)).

Complexity: Logarithmic

template<typename K> 
  std::pair< const_iterator, const_iterator > equal_range(const K & x) const;

Requires: This overload is available only if key_compare::is_transparent exists.

Effects: Equivalent to std::make_pair(this->lower_bound(k), this->upper_bound(k)).

Complexity: Logarithmic

void rebalance();

Effects: Rebalances the tree. It's a no-op for Red-Black and AVL trees.

Complexity: Linear

friend bool operator==(const multimap & x, const multimap & y);

Effects: Returns true if x and y are equal

Complexity: Linear to the number of elements in the container.

friend bool operator!=(const multimap & x, const multimap & y);

Effects: Returns true if x and y are unequal

Complexity: Linear to the number of elements in the container.

friend bool operator<(const multimap & x, const multimap & y);

Effects: Returns true if x is less than y

Complexity: Linear to the number of elements in the container.

friend bool operator>(const multimap & x, const multimap & y);

Effects: Returns true if x is greater than y

Complexity: Linear to the number of elements in the container.

friend bool operator<=(const multimap & x, const multimap & y);

Effects: Returns true if x is equal or less than y

Complexity: Linear to the number of elements in the container.

friend bool operator>=(const multimap & x, const multimap & y);

Effects: Returns true if x is equal or greater than y

Complexity: Linear to the number of elements in the container.

friend void swap(multimap & x, multimap & y);

Effects: x.swap(y)

Complexity: Constant.