A standard container made up of (key,value) pairs, which can be retrieved based on a key, in logarithmic time. More...
Meets the requirements of a container, a reversible container, and an associative container (using unique keys). For a map<Key,T>
the key_type is Key, the mapped_type is T, and the value_type is std::pair<const Key,T>.
Maps support bidirectional iterators.
Definition at line 92 of file stl_map.h.
map | ( | const _Compare & | __comp, | |
const allocator_type & | __a = allocator_type() | |||
) | [inline, explicit] |
map | ( | _InputIterator | __first, | |
_InputIterator | __last | |||
) | [inline] |
Builds a map from a range.
Create a map consisting of copies of the elements from [first,last). This is linear in N if the range is already sorted, and NlogN otherwise (where N is distance(first,last)).
map | ( | _InputIterator | __first, | |
_InputIterator | __last, | |||
const _Compare & | __comp, | |||
const allocator_type & | __a = allocator_type() | |||
) | [inline] |
Builds a map from a range.
first | An input iterator. | |
last | An input iterator. | |
comp | A comparison functor. | |
a | An allocator object. |
Create a map consisting of copies of the elements from [first,last). This is linear in N if the range is already sorted, and NlogN otherwise (where N is distance(first,last)).
mapped_type& at | ( | const key_type & | __k | ) | [inline] |
Access to map data.
k | The key for which data should be retrieved. |
std::out_of_range | If no such data is present. |
Definition at line 362 of file stl_map.h.
References std::lower_bound().
const_iterator begin | ( | ) | const [inline] |
iterator begin | ( | ) | [inline] |
void clear | ( | ) | [inline] |
size_type count | ( | const key_type & | __x | ) | const [inline] |
Finds the number of elements with given key.
x | Key of (key, value) pairs to be located. |
This function only makes sense for multimaps; for map the result will either be 0 (not present) or 1 (present).
bool empty | ( | ) | const [inline] |
const_iterator end | ( | ) | const [inline] |
iterator end | ( | ) | [inline] |
std::pair<const_iterator, const_iterator> equal_range | ( | const key_type & | __x | ) | const [inline] |
Finds a subsequence matching given key.
x | Key of (key, value) pairs to be located. |
This function is equivalent to
std::make_pair(c.lower_bound(val), c.upper_bound(val))
(but is faster than making the calls separately).
This function probably only makes sense for multimaps.
std::pair<iterator, iterator> equal_range | ( | const key_type & | __x | ) | [inline] |
Finds a subsequence matching given key.
x | Key of (key, value) pairs to be located. |
This function is equivalent to
std::make_pair(c.lower_bound(val), c.upper_bound(val))
(but is faster than making the calls separately).
This function probably only makes sense for multimaps.
void erase | ( | iterator | __first, | |
iterator | __last | |||
) | [inline] |
Erases a [first,last) range of elements from a map.
first | Iterator pointing to the start of the range to be erased. | |
last | Iterator pointing to the end of the range to be erased. |
This function erases a sequence of elements from a map. Note that this function only erases the element, and that if the element is itself a pointer, the pointed-to memory is not touched in any way. Managing the pointer is the user's responsibilty.
size_type erase | ( | const key_type & | __x | ) | [inline] |
Erases elements according to the provided key.
x | Key of element to be erased. |
This function erases all the elements located by the given key from a map. Note that this function only erases the element, and that if the element is itself a pointer, the pointed-to memory is not touched in any way. Managing the pointer is the user's responsibilty.
void erase | ( | iterator | __position | ) | [inline] |
Erases an element from a map.
position | An iterator pointing to the element to be erased. |
This function erases an element, pointed to by the given iterator, from a map. Note that this function only erases the element, and that if the element is itself a pointer, the pointed-to memory is not touched in any way. Managing the pointer is the user's responsibilty.
const_iterator find | ( | const key_type & | __x | ) | const [inline] |
Tries to locate an element in a map.
x | Key of (key, value) pair to be located. |
This function takes a key and tries to locate the element with which the key matches. If successful the function returns a constant iterator pointing to the sought after pair. If unsuccessful it returns the past-the-end ( end()
) iterator.
iterator find | ( | const key_type & | __x | ) | [inline] |
Tries to locate an element in a map.
x | Key of (key, value) pair to be located. |
This function takes a key and tries to locate the element with which the key matches. If successful the function returns an iterator pointing to the sought after pair. If unsuccessful it returns the past-the-end ( end()
) iterator.
allocator_type get_allocator | ( | ) | const [inline] |
void insert | ( | _InputIterator | __first, | |
_InputIterator | __last | |||
) | [inline] |
iterator insert | ( | iterator | position, | |
const value_type & | __x | |||
) | [inline] |
Attempts to insert a std::pair into the map.
position | An iterator that serves as a hint as to where the pair should be inserted. | |
x | Pair to be inserted (see std::make_pair for easy creation of pairs). |
This function is not concerned about whether the insertion took place, and thus does not return a boolean like the single-argument insert() does. Note that the first parameter is only a hint and can potentially improve the performance of the insertion process. A bad hint would cause no gains in efficiency.
See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4 for more on "hinting".
Insertion requires logarithmic time (if the hint is not taken).
std::pair<iterator,bool> insert | ( | const value_type & | __x | ) | [inline] |
Attempts to insert a std::pair into the map.
x | Pair to be inserted (see std::make_pair for easy creation of pairs). |
This function attempts to insert a (key, value) pair into the map. A map relies on unique keys and thus a pair is only inserted if its first element (the key) is not already present in the map.
Insertion requires logarithmic time.
key_compare key_comp | ( | ) | const [inline] |
const_iterator lower_bound | ( | const key_type & | __x | ) | const [inline] |
Finds the beginning of a subsequence matching given key.
x | Key of (key, value) pair to be located. |
This function returns the first element of a subsequence of elements that matches the given key. If unsuccessful it returns an iterator pointing to the first element that has a greater value than given key or end() if no such element exists.
iterator lower_bound | ( | const key_type & | __x | ) | [inline] |
Finds the beginning of a subsequence matching given key.
x | Key of (key, value) pair to be located. |
This function returns the first element of a subsequence of elements that matches the given key. If unsuccessful it returns an iterator pointing to the first element that has a greater value than given key or end() if no such element exists.
size_type max_size | ( | ) | const [inline] |
Map assignment operator.
The dtor only erases the elements, and note that if the elements themselves are pointers, the pointed-to memory is not touched in any way. Managing the pointer is the user's responsibilty.
x | A map of identical element and allocator types. |
All the elements of x are copied, but unlike the copy constructor, the allocator object is not copied.
mapped_type& operator[] | ( | const key_type & | __k | ) | [inline] |
Subscript ( [] ) access to map data.
k | The key for which data should be retrieved. |
Allows for easy lookup with the subscript ( [] ) operator. Returns data associated with the key specified in subscript. If the key does not exist, a pair with that key is created using default values, which is then returned.
Lookup requires logarithmic time.
Definition at line 340 of file stl_map.h.
References std::lower_bound().
const_reverse_iterator rbegin | ( | ) | const [inline] |
reverse_iterator rbegin | ( | ) | [inline] |
const_reverse_iterator rend | ( | ) | const [inline] |
reverse_iterator rend | ( | ) | [inline] |
size_type size | ( | ) | const [inline] |
void swap | ( | map< _Key, _Tp, _Compare, _Alloc > & | __x | ) | [inline] |
Swaps data with another map.
x | A map of the same element and allocator types. |
This exchanges the elements between two maps in constant time. (It is only swapping a pointer, an integer, and an instance of the Compare
type (which itself is often stateless and empty), so it should be quite fast.) Note that the global std::swap() function is specialized such that std::swap(m1,m2) will feed to this function.
Definition at line 490 of file stl_map.h.
Referenced by std::swap().
const_iterator upper_bound | ( | const key_type & | __x | ) | const [inline] |
iterator upper_bound | ( | const key_type & | __x | ) | [inline] |
value_compare value_comp | ( | ) | const [inline] |