...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::container::multimap
// In header: <boost/container/map.hpp> template<typename Key, typename T, typename Pred = std::less< std::pair< const Key, T> >, typename A = std::allocator<T> > class multimap { public: // types typedef tree_t::key_type key_type; typedef tree_t::value_type value_type; typedef tree_t::pointer pointer; typedef tree_t::const_pointer const_pointer; typedef tree_t::reference reference; typedef tree_t::const_reference const_reference; typedef T mapped_type; typedef Pred key_compare; typedef tree_t::iterator iterator; typedef tree_t::const_iterator const_iterator; typedef tree_t::reverse_iterator reverse_iterator; typedef tree_t::const_reverse_iterator const_reverse_iterator; typedef tree_t::size_type size_type; typedef tree_t::difference_type difference_type; typedef tree_t::allocator_type allocator_type; typedef tree_t::stored_allocator_type stored_allocator_type; typedef std::pair< key_type, mapped_type > nonconst_value_type; typedef unspecified nonconst_impl_value_type; typedef value_compare_impl value_compare; // construct/copy/destruct multimap(); explicit multimap(const Pred &, const allocator_type & = allocator_type()); template<typename InputIterator> multimap(InputIterator, InputIterator, const Pred & = Pred(), const allocator_type & = allocator_type()); template<typename InputIterator> multimap(ordered_range_t, InputIterator, InputIterator, const Pred & = Pred(), const allocator_type & = allocator_type()); multimap(const multimap &); multimap(BOOST_RV_REF(multimap)); multimap(const multimap &, const allocator_type &); multimap(BOOST_RV_REF(multimap), const allocator_type &); multimap& operator=(BOOST_COPY_ASSIGN_REF(multimap)); multimap& operator=(BOOST_RV_REF(multimap)); // public member functions key_compare key_comp() const; value_compare value_comp() const; allocator_type get_allocator() const; const stored_allocator_type & get_stored_allocator() const; stored_allocator_type & get_stored_allocator(); iterator begin(); const_iterator begin() const; const_iterator cbegin() const; iterator end(); const_iterator end() const; const_iterator cend() const; reverse_iterator rbegin(); const_reverse_iterator rbegin() const; const_reverse_iterator crbegin() const; reverse_iterator rend(); const_reverse_iterator rend() const; const_reverse_iterator crend() const; bool empty() const; size_type size() const; size_type max_size() const; void swap(multimap &); iterator insert(const value_type &); iterator insert(const nonconst_value_type &); iterator insert(BOOST_RV_REF(nonconst_value_type)); iterator insert(BOOST_RV_REF(nonconst_impl_value_type)); iterator insert(iterator, const value_type &); iterator insert(iterator, const nonconst_value_type &); iterator insert(iterator, BOOST_RV_REF(nonconst_value_type)); iterator insert(iterator, BOOST_RV_REF(nonconst_impl_value_type)); template<typename InputIterator> void insert(InputIterator, InputIterator); template<class... Args> iterator emplace(Args &&...); template<class... Args> iterator emplace_hint(const_iterator, Args &&...); iterator erase(const_iterator); size_type erase(const key_type &); iterator erase(const_iterator, const_iterator); void clear(); 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 &); std::pair< iterator, iterator > equal_range(const key_type &); const_iterator upper_bound(const key_type &) const; std::pair< const_iterator, const_iterator > equal_range(const key_type &) const; };
A 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 multimap class supports bidirectional iterators.
A multimap satisfies all of the requirements of a container and of a reversible container and of an associative container. For a map<Key,T> the key_type is Key and the value_type is std::pair<const Key,T>.
Pred is the ordering function for Keys (e.g. std::less<Key>).
A is the allocator to allocate the value_types (e.g. allocator< std::pair<const Key, T> >).
multimap
public
construct/copy/destructmultimap();
Effects: Default constructs an empty multimap.
Complexity: Constant.
explicit multimap(const Pred & comp, const allocator_type & a = allocator_type());
Effects: Constructs an empty multimap using the specified comparison object and allocator.
Complexity: Constant.
template<typename InputIterator> multimap(InputIterator first, InputIterator last, const Pred & comp = Pred(), const allocator_type & a = allocator_type());
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 comp and otherwise N logN, where N is last - first.
template<typename InputIterator> multimap(ordered_range_t ordered_range, InputIterator first, InputIterator last, const Pred & comp = Pred(), const allocator_type & a = allocator_type());
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.
multimap(const multimap & x);
Effects: Copy constructs a multimap.
Complexity: Linear in x.size().
multimap(BOOST_RV_REF(multimap) x);
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(BOOST_RV_REF(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=(BOOST_COPY_ASSIGN_REF(multimap) x);
Effects: Makes *this a copy of x.
Complexity: Linear in x.size().
multimap& operator=(BOOST_RV_REF(multimap) x);
Effects: this->swap(x.get()).
Complexity: Constant.
multimap
public member functionskey_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.
allocator_type get_allocator() const;
Effects: Returns a copy of the Allocator that was passed to the object's constructor.
Complexity: Constant.
const stored_allocator_type & get_stored_allocator() const;
stored_allocator_type & get_stored_allocator();
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();
Effects: Returns an iterator to the end of the container.
Throws: Nothing.
Complexity: Constant.
const_iterator end() const;
Effects: Returns a const_iterator to the end of the container.
Throws: Nothing.
Complexity: Constant.
const_iterator cend() const;
Effects: Returns a const_iterator to the end of the container.
Throws: Nothing.
Complexity: Constant.
reverse_iterator rbegin();
Effects: Returns a reverse_iterator pointing to the beginning of the reversed container.
Throws: Nothing.
Complexity: Constant.
const_reverse_iterator rbegin() const;
Effects: Returns a const_reverse_iterator pointing to the beginning of the reversed container.
Throws: Nothing.
Complexity: Constant.
const_reverse_iterator crbegin() const;
Effects: Returns a const_reverse_iterator pointing to the beginning of the reversed container.
Throws: Nothing.
Complexity: Constant.
reverse_iterator rend();
Effects: Returns a reverse_iterator pointing to the end of the reversed container.
Throws: Nothing.
Complexity: Constant.
const_reverse_iterator rend() const;
Effects: Returns a const_reverse_iterator pointing to the end of the reversed container.
Throws: Nothing.
Complexity: Constant.
const_reverse_iterator crend() const;
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.
void swap(multimap & x);
Effects: Swaps the contents of *this and x.
Throws: Nothing.
Complexity: Constant.
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(BOOST_RV_REF(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(BOOST_RV_REF(nonconst_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.
iterator insert(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 in general, but amortized constant if t is inserted right before p.
iterator insert(iterator position, 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(iterator position, BOOST_RV_REF(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(iterator position, BOOST_RV_REF(nonconst_impl_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)
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 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 in general, but amortized constant if t is inserted right before p.
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: 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.
void clear();
Effects: erase(a.begin(),a.end()).
Postcondition: size() == 0.
Complexity: linear in size().
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.
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: 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
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
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
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