stl_multimap.h
// Filename: stl_multimap.h // Comment By: 凝霜
// E-mail: [email protected]
// Blog: http://blog.csdn.net/mdl13412 /*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/ /* NOTE: This is an internal header file, included by other STL headers.
* You should not attempt to use it directly.
*/ #ifndef __SGI_STL_INTERNAL_MULTIMAP_H
#define __SGI_STL_INTERNAL_MULTIMAP_H __STL_BEGIN_NAMESPACE #if defined(__sgi) && !defined(__GNUC__) && (_MIPS_SIM != _MIPS_SIM_ABI32)
#pragma set woff 1174
#endif // 如果编译器不能根据前面模板参数推导出后面使用的默认参数类型,
// 那么就需要手工指定, 本实作multimap内部元素默认使用less进行比较
// 内部维护的数据结构是红黑树, 具有非常优秀的最坏情况的时间复杂度
// 注意: 与map不同, multimap允许有重复的元素
#ifndef __STL_LIMITED_DEFAULT_TEMPLATES
template <class Key, class T, class Compare = less<Key>, class Alloc = alloc>
#else
template <class Key, class T, class Compare, class Alloc = alloc>
#endif
class multimap
{
public:
// 这里和map定义相同, 见<setL_map.h>
typedef Key key_type;
typedef T data_type;
typedef T mapped_type;
typedef pair<const Key, T> value_type;
typedef Compare key_compare; // 关于为什么继承自binary_function见<stl_function.h>中的讲解
// 被嵌套类提供key的比较操作
class value_compare : public binary_function<value_type, value_type, bool>
{
friend class multimap<Key, T, Compare, Alloc>;
protected:
Compare comp;
value_compare(Compare c) : comp(c) {}
public:
bool operator()(const value_type& x, const value_type& y) const {
return comp(x.first, y.first);
}
}; private:
// 内部采用红黑树为数据结构, 其实现在<stl_tree.h>
typedef rb_tree<key_type, value_type,
select1st<value_type>, key_compare, Alloc> rep_type;
rep_type t; // red-black tree representing multimap public:
// 标记为'STL标准强制要求'的typedefs用于提供iterator_traits<I>支持
// 注意: 迭代器, 引用类型都设计为const, 这是由multimap的性质决定的,
// 如果用户自行更改其数值, 可能会导致内部的红黑树出现问题
typedef typename rep_type::pointer pointer; // STL标准强制要求
typedef typename rep_type::const_pointer const_pointer;
typedef typename rep_type::reference reference; // STL标准强制要求
typedef typename rep_type::const_reference const_reference;
typedef typename rep_type::iterator iterator; // STL标准强制要求
typedef typename rep_type::const_iterator const_iterator;
typedef typename rep_type::reverse_iterator reverse_iterator;
typedef typename rep_type::const_reverse_iterator const_reverse_iterator;
typedef typename rep_type::size_type size_type;
typedef typename rep_type::difference_type difference_type; // STL标准强制要求 multimap() : t(Compare()) { }
explicit multimap(const Compare& comp) : t(comp) { } #ifdef __STL_MEMBER_TEMPLATES
template <class InputIterator>
multimap(InputIterator first, InputIterator last)
: t(Compare()) { t.insert_equal(first, last); } template <class InputIterator>
multimap(InputIterator first, InputIterator last, const Compare& comp)
: t(comp) { t.insert_equal(first, last); }
#else
multimap(const value_type* first, const value_type* last)
: t(Compare()) { t.insert_equal(first, last); }
multimap(const value_type* first, const value_type* last,
const Compare& comp)
: t(comp) { t.insert_equal(first, last); } multimap(const_iterator first, const_iterator last)
: t(Compare()) { t.insert_equal(first, last); }
multimap(const_iterator first, const_iterator last, const Compare& comp)
: t(comp) { t.insert_equal(first, last); }
#endif /* __STL_MEMBER_TEMPLATES */ multimap(const multimap<Key, T, Compare, Alloc>& x) : t(x.t) { } multimap<Key, T, Compare, Alloc>&
operator=(const multimap<Key, T, Compare, Alloc>& x)
{
t = x.t;
return *this;
} // 返回用于key比较的函数
key_compare key_comp() const { return t.key_comp(); } // 由于multimap的性质, value比较和key使用同一个比较函数
value_compare value_comp() const { return value_compare(t.key_comp()); } iterator begin() { return t.begin(); }
const_iterator begin() const { return t.begin(); }
iterator end() { return t.end(); }
const_iterator end() const { return t.end(); }
reverse_iterator rbegin() { return t.rbegin(); }
const_reverse_iterator rbegin() const { return t.rbegin(); }
reverse_iterator rend() { return t.rend(); }
const_reverse_iterator rend() const { return t.rend(); }
bool empty() const { return t.empty(); }
size_type size() const { return t.size(); }
size_type max_size() const { return t.max_size(); } // 这里调用的是专用的swap, 不是全局的swap, 定于于<stl_tree.h>
void swap(multimap<Key, T, Compare, Alloc>& x) { t.swap(x.t); } // 插入元素, 注意, 插入的元素key允许重复
iterator insert(const value_type& x) { return t.insert_equal(x); } // 在position处插入元素, 但是position仅仅是个提示, 如果给出的位置不能进行插入,
// STL会进行查找, 这会导致很差的效率
iterator insert(iterator position, const value_type& x)
{
return t.insert_equal(position, x);
} #ifdef __STL_MEMBER_TEMPLATES
template <class InputIterator>
void insert(InputIterator first, InputIterator last)
{
t.insert_equal(first, last);
}
#else
void insert(const value_type* first, const value_type* last) {
t.insert_equal(first, last);
}
void insert(const_iterator first, const_iterator last) {
t.insert_equal(first, last);
}
#endif /* __STL_MEMBER_TEMPLATES */ // 擦除指定位置的元素, 会导致内部的红黑树重新排列
void erase(iterator position) { t.erase(position); } // 会返回擦除元素的个数
size_type erase(const key_type& x) { return t.erase(x); } // 擦除指定区间的元素, 会导致红黑树有较大变化
void erase(iterator first, iterator last) { t.erase(first, last); } // 好吧, clear all, 再见吧红黑树
void clear() { t.clear(); } // 查找指定的元素
iterator find(const key_type& x) { return t.find(x); }
const_iterator find(const key_type& x) const { return t.find(x); } // 返回指定元素的个数
size_type count(const key_type& x) const { return t.count(x); } // 返回小于当前元素的第一个可插入的位置
iterator lower_bound(const key_type& x) {return t.lower_bound(x); }
const_iterator lower_bound(const key_type& x) const
{
return t.lower_bound(x);
} // 返回大于当前元素的第一个可插入的位置
iterator upper_bound(const key_type& x) {return t.upper_bound(x); }
const_iterator upper_bound(const key_type& x) const
{
return t.upper_bound(x);
} pair<iterator,iterator> equal_range(const key_type& x)
{
return t.equal_range(x);
} pair<const_iterator,const_iterator> equal_range(const key_type& x) const
{
return t.equal_range(x);
} friend bool operator== __STL_NULL_TMPL_ARGS (const multimap&,
const multimap&);
friend bool operator< __STL_NULL_TMPL_ARGS (const multimap&,
const multimap&);
}; // 比较两个multimap比较的是其内部的红黑树, 会触发红黑树的operator template <class Key, class T, class Compare, class Alloc>
inline bool operator==(const multimap<Key, T, Compare, Alloc>& x,
const multimap<Key, T, Compare, Alloc>& y)
{
return x.t == y.t;
} template <class Key, class T, class Compare, class Alloc>
inline bool operator<(const multimap<Key, T, Compare, Alloc>& x,
const multimap<Key, T, Compare, Alloc>& y)
{
return x.t < y.t;
} // 如果编译器支持模板函数特化优先级
// 那么将全局的swap实现为使用multimap私有的swap以提高效率
#ifdef __STL_FUNCTION_TMPL_PARTIAL_ORDER template <class Key, class T, class Compare, class Alloc>
inline void swap(multimap<Key, T, Compare, Alloc>& x,
multimap<Key, T, Compare, Alloc>& y)
{
x.swap(y);
} #endif /* __STL_FUNCTION_TMPL_PARTIAL_ORDER */ #if defined(__sgi) && !defined(__GNUC__) && (_MIPS_SIM != _MIPS_SIM_ABI32)
#pragma reset woff 1174
#endif __STL_END_NAMESPACE #endif /* __SGI_STL_INTERNAL_MULTIMAP_H */ // Local Variables:
// mode:C++
// End: