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boost::container::flat_multimap
// In header: <boost/container/flat_map.hpp> template<typename Key, typename T, typename Compare = std::less<Key>, typename Allocator = std::allocator< std::pair< Key, T> > > class flat_multimap { public: // types typedef Key key_type; typedef T mapped_type; typedef std::pair< Key, T > value_type; typedef ::boost::container::allocator_traits< Allocator > allocator_traits_type; typedef boost::container::allocator_traits< Allocator >::pointer pointer; typedef boost::container::allocator_traits< Allocator >::const_pointer const_pointer; typedef boost::container::allocator_traits< Allocator >::reference reference; typedef boost::container::allocator_traits< Allocator >::const_reference const_reference; typedef boost::container::allocator_traits< Allocator >::size_type size_type; typedef boost::container::allocator_traits< Allocator >::difference_type difference_type; typedef Allocator allocator_type; typedef implementation_defined stored_allocator_type; typedef implementation_defined value_compare; typedef Compare key_compare; typedef implementation_defined iterator; typedef implementation_defined const_iterator; typedef implementation_defined reverse_iterator; typedef implementation_defined const_reverse_iterator; typedef implementation_defined movable_value_type; // construct/copy/destruct flat_multimap(); explicit flat_multimap(const Compare &, const allocator_type & = allocator_type()); explicit flat_multimap(const allocator_type &); template<typename InputIterator> flat_multimap(InputIterator, InputIterator, const Compare & = Compare(), const allocator_type & = allocator_type()); template<typename InputIterator> flat_multimap(ordered_range_t, InputIterator, InputIterator, const Compare & = Compare(), const allocator_type & = allocator_type()); flat_multimap(const flat_multimap &); flat_multimap(flat_multimap &&); flat_multimap(const flat_multimap &, const allocator_type &); flat_multimap(flat_multimap &&, const allocator_type &); flat_multimap & operator=(const flat_multimap &); flat_multimap & operator=(flat_multimap &&) noexcept(allocator_traits_type::propagate_on_container_move_assignment::value)); // public member functions allocator_type get_allocator() const noexcept; stored_allocator_type & get_stored_allocator() noexcept; const stored_allocator_type & get_stored_allocator() const noexcept; iterator begin() noexcept; const_iterator begin() const noexcept; iterator end() noexcept; const_iterator end() const noexcept; reverse_iterator rbegin() noexcept; const_reverse_iterator rbegin() const noexcept; reverse_iterator rend() noexcept; const_reverse_iterator rend() const noexcept; const_iterator cbegin() const noexcept; const_iterator cend() const noexcept; const_reverse_iterator crbegin() const noexcept; const_reverse_iterator crend() const noexcept; bool empty() const noexcept; size_type size() const noexcept; size_type max_size() const noexcept; size_type capacity() const noexcept; void reserve(size_type); void shrink_to_fit(); template<class... Args> iterator emplace(Args &&...); template<class... Args> iterator emplace_hint(const_iterator, Args &&...); iterator insert(const value_type &); iterator insert(value_type &&); iterator insert(impl_value_type &&); iterator insert(const_iterator, const value_type &); iterator insert(const_iterator, value_type &&); iterator insert(const_iterator, impl_value_type &&); template<typename InputIterator> void insert(InputIterator, InputIterator); template<typename InputIterator> void insert(ordered_range_t, InputIterator, InputIterator); iterator erase(const_iterator); size_type erase(const key_type &); iterator erase(const_iterator, const_iterator); void swap(flat_multimap &); void clear() noexcept; key_compare key_comp() const; value_compare value_comp() const; iterator find(const key_type &); const_iterator find(const key_type &) const; size_type count(const key_type &) const; iterator lower_bound(const key_type &); const_iterator lower_bound(const key_type &) const; iterator upper_bound(const key_type &); const_iterator upper_bound(const key_type &) const; std::pair< iterator, iterator > equal_range(const key_type &); std::pair< const_iterator, const_iterator > equal_range(const key_type &) const; // friend functions friend bool operator==(const flat_multimap &, const flat_multimap &); friend bool operator!=(const flat_multimap &, const flat_multimap &); friend bool operator<(const flat_multimap &, const flat_multimap &); friend bool operator>(const flat_multimap &, const flat_multimap &); friend bool operator<=(const flat_multimap &, const flat_multimap &); friend bool operator>=(const flat_multimap &, const flat_multimap &); friend void swap(flat_multimap &, flat_multimap &); };
A flat_multimap is a kind of associative container that supports equivalent keys (possibly containing multiple copies of the same key value) and provides for fast retrieval of values of another type T based on the keys. The flat_multimap class supports random-access iterators.
A flat_multimap satisfies all of the requirements of a container and of a reversible container and of an associative container. For a flat_multimap<Key,T> the key_type is Key and the value_type is std::pair<Key,T> (unlike std::multimap<Key, T> which value_type is std::pair<const Key, T>).
Compare is the ordering function for Keys (e.g. std::less<Key>).
Allocator is the allocator to allocate the value_types (e.g. allocator< std::pair<Key, T> >).
flat_multimap is similar to std::multimap but it's implemented like an ordered vector. This means that inserting a new element into a flat_map invalidates previous iterators and references
Erasing an element invalidates iterators and references pointing to elements that come after (their keys are bigger) the erased element.
This container provides random-access iterators.
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 = std::allocator< std::pair< Key, T> >
is the allocator to allocate the value_type
s (e.g. allocator< std::pair<Key, T> > ).
flat_multimap
public
construct/copy/destructflat_multimap();
Effects: Default constructs an empty flat_map
.
Complexity: Constant.
explicit flat_multimap(const Compare & comp, const allocator_type & a = allocator_type());
Effects: Constructs an empty flat_multimap
using the specified comparison object and allocator.
Complexity: Constant.
explicit flat_multimap(const allocator_type & a);
Effects: Constructs an empty flat_multimap
using the specified allocator.
Complexity: Constant.
template<typename InputIterator> flat_multimap(InputIterator first, InputIterator last, const Compare & comp = Compare(), const allocator_type & a = allocator_type());
Effects: Constructs an empty flat_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 comp and otherwise N logN, where N is last - first.
template<typename InputIterator> flat_multimap(ordered_range_t, InputIterator first, InputIterator last, const Compare & comp = Compare(), const allocator_type & a = allocator_type());
Effects: Constructs an empty flat_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.
flat_multimap(const flat_multimap & x);
Effects: Copy constructs a flat_multimap
.
Complexity: Linear in x.size().
flat_multimap(flat_multimap && x);
Effects: Move constructs a flat_multimap
. Constructs *this using x's resources.
Complexity: Constant.
Postcondition: x is emptied.
flat_multimap(const flat_multimap & x, const allocator_type & a);
Effects: Copy constructs a flat_multimap
using the specified allocator.
Complexity: Linear in x.size().
flat_multimap(flat_multimap && x, const allocator_type & a);
Effects: Move constructs a flat_multimap
using the specified allocator. Constructs *this using x's resources.
Complexity: Constant if a == x.get_allocator(), linear otherwise.
flat_multimap & operator=(const flat_multimap & x);
Effects: Makes *this a copy of x.
Complexity: Linear in x.size().
flat_multimap & operator=(flat_multimap && x) noexcept(allocator_traits_type::propagate_on_container_move_assignment::value));
Effects: this->swap(x.get()).
Complexity: Constant.
flat_multimap
public member functionsallocator_type get_allocator() const noexcept;
Effects: Returns a copy of the Allocator that was passed to the object's constructor.
Complexity: Constant.
stored_allocator_type & get_stored_allocator() noexcept;
Effects: Returns a reference to the internal allocator.
Throws: Nothing
Complexity: Constant.
Note: Non-standard extension.
const stored_allocator_type & get_stored_allocator() const noexcept;
Effects: Returns a reference to the internal allocator.
Throws: Nothing
Complexity: Constant.
Note: Non-standard extension.
iterator begin() noexcept;
Effects: Returns an iterator to the first element contained in the container.
Throws: Nothing.
Complexity: Constant.
const_iterator begin() const noexcept;
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.
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.
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_iterator cbegin() const noexcept;
Effects: Returns a const_iterator to the first element contained in 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.
const_reverse_iterator crbegin() const noexcept;
Effects: Returns a const_reverse_iterator pointing to the beginning 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 noexcept;
Effects: Returns true if the container contains no elements.
Throws: Nothing.
Complexity: Constant.
size_type size() const noexcept;
Effects: Returns the number of the elements contained in the container.
Throws: Nothing.
Complexity: Constant.
size_type max_size() const noexcept;
Effects: Returns the largest possible size of the container.
Throws: Nothing.
Complexity: Constant.
size_type capacity() const noexcept;
Effects: Number of elements for which memory has been allocated. capacity() is always greater than or equal to size().
Throws: Nothing.
Complexity: Constant.
void reserve(size_type cnt);
Effects: If n is less than or equal to capacity(), this call has no effect. Otherwise, it is a request for allocation of additional memory. If the request is successful, then capacity() is greater than or equal to n; otherwise, capacity() is unchanged. In either case, size() is unchanged.
Throws: If memory allocation allocation throws or T's copy constructor throws.
Note: If capacity() is less than "cnt", iterators and references to to values might be invalidated.
void shrink_to_fit();Effects: Tries to deallocate the excess of memory created
Throws: If memory allocation throws, or T's copy constructor throws.
Complexity: Linear to size().
template<class... Args> iterator emplace(Args &&... args);
Effects: Inserts an object of type T constructed with std::forward<Args>(args)... and returns the iterator pointing to the newly inserted element.
Complexity: Logarithmic search time plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
template<class... Args> iterator emplace_hint(const_iterator hint, 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 search time (constant time if the value is to be inserted before p) plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
iterator insert(const value_type & x);
Effects: Inserts x and returns the iterator pointing to the newly inserted element.
Complexity: Logarithmic search time plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
iterator insert(value_type && x);
Effects: Inserts a new value move-constructed from x and returns the iterator pointing to the newly inserted element.
Complexity: Logarithmic search time plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
iterator insert(impl_value_type && x);
Effects: Inserts a new value move-constructed from x and returns the iterator pointing to the newly inserted element.
Complexity: Logarithmic search time plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
iterator insert(const_iterator position, 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 search time (constant time if the value is to be inserted before p) plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
iterator insert(const_iterator position, value_type && x);
Effects: Inserts a 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 search time (constant time if the value is to be inserted before p) plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
iterator insert(const_iterator position, impl_value_type && x);
Effects: Inserts a 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 search time (constant time if the value is to be inserted before p) plus linear insertion to the elements with bigger keys than x.
Note: If an element is inserted it might invalidate elements.
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) search time plus N*size() insertion time.
Note: If an element is inserted it might invalidate elements.
template<typename InputIterator> void insert(ordered_range_t, InputIterator first, InputIterator last);
Requires: first, last are not iterators into *this.
Requires: [first ,last) must be ordered according to the predicate.
Effects: inserts each element from the range [first,last) if and only if there is no element with key equivalent to the key of that element. This function is more efficient than the normal range creation for ordered ranges.
Complexity: At most N log(size()+N) (N is the distance from first to last) search time plus N*size() insertion time.
Note: If an element is inserted it might invalidate elements.
Note: Non-standard extension.
iterator erase(const_iterator position);
Effects: Erases the element pointed to by position.
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: Linear to the elements with keys bigger than position
Note: Invalidates elements with keys not less than the erased element.
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: Logarithmic search time plus erasure time linear to the elements with bigger keys.
iterator erase(const_iterator first, const_iterator last);
Effects: Erases all the elements in the range [first, last).
Returns: Returns last.
Complexity: size()*N where N is the distance from first to last.
Complexity: Logarithmic search time plus erasure time linear to the elements with bigger keys.
void swap(flat_multimap & x);
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: An 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)
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: Allocator 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: Allocator 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
flat_multimap
friend functionsfriend bool operator==(const flat_multimap & x, const flat_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 flat_multimap & x, const flat_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 flat_multimap & x, const flat_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 flat_multimap & x, const flat_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 flat_multimap & x, const flat_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 flat_multimap & x, const flat_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(flat_multimap & x, flat_multimap & y);
Effects: x.swap(y)
Complexity: Constant.