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// xhash internal header #pragma once #ifndef _XHASH_ #define _XHASH_ #include <functional> #include <list> #include <vector>
#pragma pack(push,8) #pragma warning(push,3)
#pragma warning(disable: 4127) _STD_BEGIN
// TEMPLATE CLASS hash_compare template<class _Kty, class _Pr = less<_Kty> > class hash_compare { // traits class for hash containers public: enum { // parameters for hash table bucket_size = 4, // 0 < bucket_size min_buckets = 8}; // min_buckets = 2 ^^ N, 0 < N
hash_compare() : comp() { // construct with default comparator }
hash_compare(_Pr _Pred) : comp(_Pred) { // construct with _Pred comparator }
size_t operator()(const _Kty& _Keyval) const { // hash _Keyval to size_t value return ((size_t)_Keyval); }
// size_t operator()(const _Kty& _Keyval) const // { // hash _Keyval to size_t value by pseudorandomizing transform // ldiv_t _Qrem = ldiv((size_t)_Keyval, 127773); // _Qrem.rem = 16807 * _Qrem.rem - 2836 * _Qrem.quot; // if (_Qrem.rem < 0) // _Qrem.rem += 2147483647; // return ((size_t)_Qrem.rem); }
bool operator()(const _Kty& _Keyval1, const _Kty& _Keyval2) const { // test if _Keyval1 ordered before _Keyval2 return (comp(_Keyval1, _Keyval2)); }
private: _Pr comp; // the comparator object };
// TEMPLATE CLASS _Hash template<class _Tr> class _Hash : public _Tr // traits serves as base class { // hash table -- list with vector of iterators for quick access public: typedef _Hash<_Tr> _Myt; typedef typename _Tr::key_type key_type; typedef typename _Tr::key_compare key_compare; typedef typename _Tr::value_compare value_compare; enum { // hoist constants from key_compare bucket_size = key_compare::bucket_size, min_buckets = key_compare::min_buckets, _Multi = _Tr::_Multi}; typedef list<typename _Tr::value_type, typename _Tr::allocator_type> _Mylist;
typedef typename _Mylist::allocator_type allocator_type; typedef typename _Mylist::size_type size_type; typedef typename _Mylist::difference_type difference_type; typedef typename _Mylist::pointer pointer; typedef typename _Mylist::const_pointer const_pointer; typedef typename _Mylist::reference reference; typedef typename _Mylist::const_reference const_reference; typedef typename _Mylist::iterator iterator; typedef typename _Mylist::const_iterator const_iterator; typedef typename _Mylist::reverse_iterator reverse_iterator; typedef typename _Mylist::const_reverse_iterator const_reverse_iterator; typedef typename _Mylist::value_type value_type;
typedef vector<iterator, typename allocator_type::_TEMPLATE_MEMBER rebind<iterator>::other> _Myvec; typedef pair<iterator, bool> _Pairib; typedef pair<iterator, iterator> _Pairii; typedef pair<const_iterator, const_iterator> _Paircc;
explicit _Hash(const key_compare& _Traits, const allocator_type& _Al) : _Tr(_Traits), _List(_Al), _Vec(min_buckets + 1, end(), _Al), _Mask(1), _Maxidx(1) { // construct empty hash table }
_Hash(const value_type *_First, const value_type *_Last, const key_compare& _Traits, const allocator_type& _Al) : _Tr(_Traits), _List(_Al), _Vec(min_buckets + 1, end(), _Al), _Mask(1), _Maxidx(1) { // construct hash table from [_First, _Last) array insert(_First, _Last); }
_Hash(const _Myt& _Right) : _Tr(_Right.comp), _List(_Right.get_allocator()), _Vec(_Right.get_allocator()) { // construct hash table by copying right _Copy(_Right); }
~_Hash() { // destroy hash table }
_Myt& operator=(const _Myt& _Right) { // replace contents from _Right if (this != &_Right) _Copy(_Right); return (*this); }
iterator begin() { // return iterator for beginning of mutable sequence return (_List.begin()); }
const_iterator begin() const { // return iterator for beginning of nonmutable sequence return (_List.begin()); }
iterator end() { // return iterator for end of mutable sequence return (_List.end()); }
const_iterator end() const { // return iterator for end of nonmutable sequence return (_List.end()); }
reverse_iterator rbegin() { // return iterator for beginning of reversed mutable sequence return (_List.rbegin()); }
const_reverse_iterator rbegin() const { // return iterator for beginning of reversed nonmutable sequence return (_List.rbegin()); }
reverse_iterator rend() { // return iterator for end of reversed mutable sequence return (_List.rend()); }
const_reverse_iterator rend() const { // return iterator for end of reversed nonmutable sequence return (_List.rend()); }
size_type size() const { // return length of sequence return (_List.size()); }
size_type max_size() const { // return maximum possible length of sequence return (_List.max_size()); }
bool empty() const { // return true only if sequence is empty return (_List.empty()); }
allocator_type get_allocator() const { // return allocator object for values return (_List.get_allocator()); }
key_compare key_comp() const { // return object for comparing keys return (this->comp); }
value_compare value_comp() const { // return object for comparing values return (value_compare(key_comp())); }
_Pairib insert(const value_type& _Val) { // try to insert node with value _Val iterator _Plist, _Where; if (_Maxidx <= size() / bucket_size) { // too dense, need to grow hash table if (_Vec.size() - 1 <= _Maxidx) { // table full, double its size _Mask = ((_Vec.size() - 1) << 1) - 1; _Vec.resize(_Mask + 2, end()); } else if (_Mask < _Maxidx) _Mask = (_Mask << 1) + 1;
size_type _Bucket = _Maxidx - (_Mask >> 1) - 1; for (_Plist = _Vec[_Bucket]; _Plist != _Vec[_Bucket + 1]; ) if ((this->comp(this->_Kfn(*_Plist)) & _Mask) == _Bucket) ++_Plist; // leave element in old bucket else { // move element to new bucket iterator _Pnext = _Plist; size_type _Idx; for (_Idx = _Maxidx; _Bucket < _Idx; --_Idx) { // update end iterators if new bucket filled if (_Vec[_Idx] != end()) break; _Vec[_Idx] = _Plist; } if (++_Pnext == end()) break; else { // not at end, move it for (_Idx = _Bucket; _Plist == _Vec[_Idx]; --_Idx) { // update end iterators if moving first ++_Vec[_Idx]; if (_Idx == 0) break; } _List.splice(end(), _List, _Plist); _Plist = _Pnext; _Vec[_Maxidx + 1] = end(); } }
++_Maxidx; // open new bucket for hash lookup }
size_type _Bucket = _Hashval(this->_Kfn(_Val)); for (_Plist = _Vec[_Bucket + 1]; _Plist != _Vec[_Bucket]; ) if (this->comp(this->_Kfn(_Val), this->_Kfn(*--_Plist))) ; // still too high in bucket list else if (this->comp(this->_Kfn(*_Plist), this->_Kfn(_Val))) { // found insertion point, back up to it ++_Plist; break; } else if (_Multi) break; // equivalent, insert only if multi else return (_Pairib(_Plist, false)); // already present
_Where = _List.insert(_Plist, _Val); // insert new element for (; _Plist == _Vec[_Bucket]; --_Bucket) { // update end iterators if new first bucket element _Vec[_Bucket] = _Where; if (_Bucket == 0) break; }
return (_Pairib(_Where, true)); // return iterator for new element }
iterator insert(iterator, const value_type& _Val) { // try to insert node with value _Val, ignore hint return (insert(_Val).first); }
template<class _Iter> void insert(_Iter _First, _Iter _Last) { // insert [_First, _Last) one at a time for (; _First != _Last; ++_First) insert(*_First); }
iterator erase(iterator _Where) { // erase element at _Where size_type _Bucket = _Hashval(this->_Kfn(*_Where)); for (; _Where == _Vec[_Bucket]; --_Bucket) { // update end iterators if erasing first ++_Vec[_Bucket]; if (_Bucket == 0) break; } return (_List.erase(_Where)); }
iterator erase(iterator _First, iterator _Last) { // erase [_First, _Last) if (_First == begin() && _Last == end()) { // erase all clear(); return (begin()); } else { // partial erase, one at a time while (_First != _Last) erase(_First++); return (_First); } }
size_type erase(const key_type& _Keyval) { // erase and count all that match _Keyval _Pairii _Where = equal_range(_Keyval); size_type _Num = 0; _Distance(_Where.first, _Where.second, _Num); erase(_Where.first, _Where.second); return (_Num); }
void erase(const key_type *_First, const key_type *_Last) { // erase all that match array of keys [_First, _Last) for (; _First != _Last; ++_First) erase(*_First); }
void clear() { // erase all _List.clear(); _Vec.assign(min_buckets + 1, end()); _Mask = 1; _Maxidx = 1; }
iterator find(const key_type& _Keyval) { // find an element in mutable hash table that matches _Keyval return (lower_bound(_Keyval)); }
const_iterator find(const key_type& _Keyval) const { // find an element in nonmutable hash table that matches _Keyval return (lower_bound(_Keyval)); }
size_type count(const key_type& _Keyval) const { // count all elements that match _Keyval _Paircc _Ans = equal_range(_Keyval); size_type _Num = 0; _Distance(_Ans.first, _Ans.second, _Num); return (_Num); }
iterator lower_bound(const key_type& _Keyval) { // find leftmost not less than _Keyval in mutable hash table size_type _Bucket = _Hashval(_Keyval); iterator _Where; for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where) if (!this->comp(this->_Kfn(*_Where), _Keyval)) return (this->comp(_Keyval, this->_Kfn(*_Where)) ? end() : _Where); return (end()); }
const_iterator lower_bound(const key_type& _Keyval) const { // find leftmost not less than _Keyval in nonmutable hash table size_type _Bucket = _Hashval(_Keyval); const_iterator _Where; for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where) if (!this->comp(this->_Kfn(*_Where), _Keyval)) return (this->comp(_Keyval, this->_Kfn(*_Where)) ? end() : _Where); return (end()); }
iterator upper_bound(const key_type& _Keyval) { // find leftmost not greater than _Keyval in mutable hash table size_type _Bucket = _Hashval(_Keyval); iterator _Where; for (_Where = _Vec[_Bucket + 1]; _Where != _Vec[_Bucket]; ) if (!this->comp(_Keyval, this->_Kfn(*--_Where))) return (this->comp(this->_Kfn(*_Where), _Keyval) ? end() : ++_Where); return (end()); }
const_iterator upper_bound(const key_type& _Keyval) const { // find leftmost not greater than _Keyval in nonmutable hash table size_type _Bucket = _Hashval(_Keyval); const_iterator _Where; for (_Where = _Vec[_Bucket + 1]; _Where != _Vec[_Bucket]; ) if (!this->comp(_Keyval, this->_Kfn(*--_Where))) return (this->comp(this->_Kfn(*_Where), _Keyval) ? end() : ++_Where); return (end()); }
_Pairii equal_range(const key_type& _Keyval) { // find range equivalent to _Keyval in mutable hash table size_type _Bucket = _Hashval(_Keyval); iterator _First, _Where; for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where) if (!this->comp(this->_Kfn(*_Where), _Keyval)) { // found _First, look for end of range for (_First = _Where; _Where != _Vec[_Bucket + 1]; ++_Where) if (this->comp(_Keyval, this->_Kfn(*_Where))) break; if (_First == _Where) break; return (_Pairii(_First, _Where)); } return (_Pairii(end(), end())); }
_Paircc equal_range(const key_type& _Keyval) const { // find range equivalent to _Keyval in nonmutable hash table size_type _Bucket = _Hashval(_Keyval); iterator _First, _Where; for (_Where = _Vec[_Bucket]; _Where != _Vec[_Bucket + 1]; ++_Where) if (!this->comp(this->_Kfn(*_Where), _Keyval)) { // found _First, look for end of range for (_First = _Where; _Where != _Vec[_Bucket + 1]; ++_Where) if (this->comp(_Keyval, this->_Kfn(*_Where))) break; if (_First == _Where) break; return (_Paircc(_First, _Where)); } return (_Paircc(end(), end())); }
void swap(_Myt& _Right) { // exchange contents with _Right if (get_allocator() == _Right.get_allocator()) { // same allocator, swap control information _List.swap(_Right._List); std::swap(_Vec, _Right._Vec); std::swap(_Mask, _Right._Mask); std::swap(_Maxidx, _Right._Maxidx); std::swap(this->comp, _Right.comp); } else { // different allocator, do multiple assigns _Myt _Tmp = *this; *this = _Right, _Right = _Tmp; } }
protected: void _Copy(const _Myt& _Right) { // copy entire hash table _Vec.resize(_Right._Vec.size(), end()); _Mask = _Right._Mask; _Maxidx = _Right._Maxidx; _List.clear();
_TRY_BEGIN _List.insert(end(), _Right._List.begin(), _Right._List.end()); this->comp = _Right.comp; _CATCH_ALL _List.clear(); // list or compare copy failed, bail out fill(_Vec.begin(), _Vec.end(), end()); _RERAISE; _CATCH_END
iterator _Whereto = begin(); const_iterator _Wherefrom = _Right.begin(); for (size_type _Bucket = 0; _Bucket < _Vec.size(); ) if (_Wherefrom == _Right._Vec[_Bucket]) _Vec[_Bucket] = _Whereto, ++_Bucket; else ++_Whereto, ++_Wherefrom; }
size_type _Hashval(const key_type& _Keyval) const { // return hash value, masked and wrapped to current table size size_type _Num = this->comp(_Keyval) & _Mask; if (_Maxidx <= _Num) _Num -= (_Mask >> 1) + 1; return (_Num); }
_Mylist _List; // the list of elements, must initialize before _Vec _Myvec _Vec; // the vector of list iterators size_type _Mask; // the key mask size_type _Maxidx; // current maximum key value };
// _Hash TEMPLATE FUNCTIONS template<class _Tr> inline bool operator==(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right) { // test for hash table equality return (_Left.size() == _Right.size() && equal(_Left.begin(), _Left.end(), _Right.begin())); }
template<class _Tr> inline bool operator!=(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right) { // test for hash table inequality return (!(_Left == _Right)); }
template<class _Tr> inline bool operator<(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right) { // test if _Left < _Right for hash tables return (lexicographical_compare(_Left.begin(), _Left.end(), _Right.begin(), _Right.end())); }
template<class _Tr> inline bool operator>(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right) { // test if _Left > _Right for hash tables return (_Right < _Left); }
template<class _Tr> inline bool operator<=(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right) { // test if _Left <= _Right for hash tables return (!(_Right < _Left)); }
template<class _Tr> inline bool operator>=(const _Hash<_Tr>& _Left, const _Hash<_Tr>& _Right) { // test if _Left >= _Right for hash tables return (!(_Left < _Right)); }
template<class _Tr> inline void swap(_Hash<_Tr>& _Left, _Hash<_Tr>& _Right) { // swap _Left and _Right hash tables _Left.swap(_Right); } _STD_END #pragma warning(default: 4127) #pragma warning(pop) #pragma pack(pop)
#endif /* _XHASH_ */
/* * Copyright (c) 1992-2001 by P.J. Plauger. ALL RIGHTS RESERVED. * Consult your license regarding permissions and restrictions. V3.10:0009 */
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