📄 stl_map.h
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* to the possibly inserted pair, and the second is a bool that
* is true if the pair was actually inserted.
*
* 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.
*/
pair<iterator,bool>
insert(const value_type& __x)
{ return _M_t.insert_unique(__x); }
/**
* @brief Attempts to insert a std::pair into the %map.
* @param position An iterator that serves as a hint as to where the
* pair should be inserted.
* @param x Pair to be inserted (see std::make_pair for easy creation of
* pairs).
* @return An iterator that points to the element with key of @a x (may
* or may not be the %pair passed in).
*
* 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).
*/
iterator
insert(iterator position, const value_type& __x)
{ return _M_t.insert_unique(position, __x); }
/**
* @brief A template function that attemps to insert a range of elements.
* @param first Iterator pointing to the start of the range to be
* inserted.
* @param last Iterator pointing to the end of the range.
*
* Complexity similar to that of the range constructor.
*/
template <typename _InputIterator>
void
insert(_InputIterator __first, _InputIterator __last)
{ _M_t.insert_unique(__first, __last); }
/**
* @brief Erases an element from a %map.
* @param 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.
*/
void
erase(iterator __position)
{ _M_t.erase(__position); }
/**
* @brief Erases elements according to the provided key.
* @param x Key of element to be erased.
* @return The number of elements 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.
*/
size_type
erase(const key_type& __x)
{ return _M_t.erase(__x); }
/**
* @brief Erases a [first,last) range of elements from a %map.
* @param first Iterator pointing to the start of the range to be
* erased.
* @param 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.
*/
void
erase(iterator __first, iterator __last)
{ _M_t.erase(__first, __last); }
/**
* @brief Swaps data with another %map.
* @param 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 @c 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.
*/
void
swap(map& __x)
{ _M_t.swap(__x._M_t); }
/**
* Erases all elements in a %map. Note that this function only erases
* the elements, and 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.
*/
void
clear()
{ _M_t.clear(); }
// observers
/**
* Returns the key comparison object out of which the %map was
* constructed.
*/
key_compare
key_comp() const
{ return _M_t.key_comp(); }
/**
* Returns a value comparison object, built from the key comparison
* object out of which the %map was constructed.
*/
value_compare
value_comp() const
{ return value_compare(_M_t.key_comp()); }
// [23.3.1.3] map operations
/**
* @brief Tries to locate an element in a %map.
* @param x Key of (key, value) %pair to be located.
* @return Iterator pointing to sought-after element, or end() if not
* found.
*
* 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 ( @c end() ) iterator.
*/
iterator
find(const key_type& __x)
{ return _M_t.find(__x); }
/**
* @brief Tries to locate an element in a %map.
* @param x Key of (key, value) %pair to be located.
* @return Read-only (constant) iterator pointing to sought-after
* element, or end() if not found.
*
* 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 ( @c end() ) iterator.
*/
const_iterator
find(const key_type& __x) const
{ return _M_t.find(__x); }
/**
* @brief Finds the number of elements with given key.
* @param x Key of (key, value) pairs to be located.
* @return Number of elements with specified key.
*
* This function only makes sense for multimaps; for map the result will
* either be 0 (not present) or 1 (present).
*/
size_type
count(const key_type& __x) const
{ return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Iterator pointing to first element equal to or greater
* than key, or end().
*
* 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)
{ return _M_t.lower_bound(__x); }
/**
* @brief Finds the beginning of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to first element
* equal to or greater than key, or end().
*
* 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.
*/
const_iterator
lower_bound(const key_type& __x) const
{ return _M_t.lower_bound(__x); }
/**
* @brief Finds the end of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Iterator pointing to the first element
* greater than key, or end().
*/
iterator
upper_bound(const key_type& __x)
{ return _M_t.upper_bound(__x); }
/**
* @brief Finds the end of a subsequence matching given key.
* @param x Key of (key, value) pair to be located.
* @return Read-only (constant) iterator pointing to first iterator
* greater than key, or end().
*/
const_iterator
upper_bound(const key_type& __x) const
{ return _M_t.upper_bound(__x); }
/**
* @brief Finds a subsequence matching given key.
* @param x Key of (key, value) pairs to be located.
* @return Pair of iterators that possibly points to the subsequence
* matching given key.
*
* This function is equivalent to
* @code
* std::make_pair(c.lower_bound(val),
* c.upper_bound(val))
* @endcode
* (but is faster than making the calls separately).
*
* This function probably only makes sense for multimaps.
*/
pair<iterator,iterator>
equal_range(const key_type& __x)
{ return _M_t.equal_range(__x); }
/**
* @brief Finds a subsequence matching given key.
* @param x Key of (key, value) pairs to be located.
* @return Pair of read-only (constant) iterators that possibly points
* to the subsequence matching given key.
*
* This function is equivalent to
* @code
* std::make_pair(c.lower_bound(val),
* c.upper_bound(val))
* @endcode
* (but is faster than making the calls separately).
*
* This function probably only makes sense for multimaps.
*/
pair<const_iterator,const_iterator>
equal_range(const key_type& __x) const
{ return _M_t.equal_range(__x); }
template <typename _K1, typename _T1, typename _C1, typename _A1>
friend bool
operator== (const map<_K1,_T1,_C1,_A1>&,
const map<_K1,_T1,_C1,_A1>&);
template <typename _K1, typename _T1, typename _C1, typename _A1>
friend bool
operator< (const map<_K1,_T1,_C1,_A1>&,
const map<_K1,_T1,_C1,_A1>&);
};
/**
* @brief Map equality comparison.
* @param x A %map.
* @param y A %map of the same type as @a x.
* @return True iff the size and elements of the maps are equal.
*
* This is an equivalence relation. It is linear in the size of the
* maps. Maps are considered equivalent if their sizes are equal,
* and if corresponding elements compare equal.
*/
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator==(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y)
{ return __x._M_t == __y._M_t; }
/**
* @brief Map ordering relation.
* @param x A %map.
* @param y A %map of the same type as @a x.
* @return True iff @a x is lexicographically less than @a y.
*
* This is a total ordering relation. It is linear in the size of the
* maps. The elements must be comparable with @c <.
*
* See std::lexicographical_compare() for how the determination is made.
*/
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator<(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y)
{ return __x._M_t < __y._M_t; }
/// Based on operator==
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator!=(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y)
{ return !(__x == __y); }
/// Based on operator<
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator>(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y)
{ return __y < __x; }
/// Based on operator<
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator<=(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y)
{ return !(__y < __x); }
/// Based on operator<
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline bool
operator>=(const map<_Key,_Tp,_Compare,_Alloc>& __x,
const map<_Key,_Tp,_Compare,_Alloc>& __y)
{ return !(__x < __y); }
/// See std::map::swap().
template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
inline void
swap(map<_Key,_Tp,_Compare,_Alloc>& __x, map<_Key,_Tp,_Compare,_Alloc>& __y)
{ __x.swap(__y); }
} // namespace std
#endif /* _MAP_H */
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