📄 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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