00001 // Set implementation -*- C++ -*- 00002 00003 // Copyright (C) 2001, 2002, 2004, 2005 Free Software Foundation, Inc. 00004 // 00005 // This file is part of the GNU ISO C++ Library. This library is free 00006 // software; you can redistribute it and/or modify it under the 00007 // terms of the GNU General Public License as published by the 00008 // Free Software Foundation; either version 2, or (at your option) 00009 // any later version. 00010 00011 // This library is distributed in the hope that it will be useful, 00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00014 // GNU General Public License for more details. 00015 00016 // You should have received a copy of the GNU General Public License along 00017 // with this library; see the file COPYING. If not, write to the Free 00018 // Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 00019 // USA. 00020 00021 // As a special exception, you may use this file as part of a free software 00022 // library without restriction. Specifically, if other files instantiate 00023 // templates or use macros or inline functions from this file, or you compile 00024 // this file and link it with other files to produce an executable, this 00025 // file does not by itself cause the resulting executable to be covered by 00026 // the GNU General Public License. This exception does not however 00027 // invalidate any other reasons why the executable file might be covered by 00028 // the GNU General Public License. 00029 00030 /* 00031 * 00032 * Copyright (c) 1994 00033 * Hewlett-Packard Company 00034 * 00035 * Permission to use, copy, modify, distribute and sell this software 00036 * and its documentation for any purpose is hereby granted without fee, 00037 * provided that the above copyright notice appear in all copies and 00038 * that both that copyright notice and this permission notice appear 00039 * in supporting documentation. Hewlett-Packard Company makes no 00040 * representations about the suitability of this software for any 00041 * purpose. It is provided "as is" without express or implied warranty. 00042 * 00043 * 00044 * Copyright (c) 1996,1997 00045 * Silicon Graphics Computer Systems, Inc. 00046 * 00047 * Permission to use, copy, modify, distribute and sell this software 00048 * and its documentation for any purpose is hereby granted without fee, 00049 * provided that the above copyright notice appear in all copies and 00050 * that both that copyright notice and this permission notice appear 00051 * in supporting documentation. Silicon Graphics makes no 00052 * representations about the suitability of this software for any 00053 * purpose. It is provided "as is" without express or implied warranty. 00054 */ 00055 00056 /** @file stl_set.h 00057 * This is an internal header file, included by other library headers. 00058 * You should not attempt to use it directly. 00059 */ 00060 00061 #ifndef _SET_H 00062 #define _SET_H 1 00063 00064 #include <bits/concept_check.h> 00065 00066 namespace _GLIBCXX_STD 00067 { 00068 // Forward declarations of operators < and ==, needed for friend declaration. 00069 template<class _Key, class _Compare = std::less<_Key>, 00070 class _Alloc = std::allocator<_Key> > 00071 class set; 00072 00073 template<class _Key, class _Compare, class _Alloc> 00074 inline bool 00075 operator==(const set<_Key, _Compare, _Alloc>& __x, 00076 const set<_Key, _Compare, _Alloc>& __y); 00077 00078 template<class _Key, class _Compare, class _Alloc> 00079 inline bool 00080 operator<(const set<_Key, _Compare, _Alloc>& __x, 00081 const set<_Key, _Compare, _Alloc>& __y); 00082 00083 /** 00084 * @brief A standard container made up of unique keys, which can be 00085 * retrieved in logarithmic time. 00086 * 00087 * @ingroup Containers 00088 * @ingroup Assoc_containers 00089 * 00090 * Meets the requirements of a <a href="tables.html#65">container</a>, a 00091 * <a href="tables.html#66">reversible container</a>, and an 00092 * <a href="tables.html#69">associative container</a> (using unique keys). 00093 * 00094 * Sets support bidirectional iterators. 00095 * 00096 * @param Key Type of key objects. 00097 * @param Compare Comparison function object type, defaults to less<Key>. 00098 * @param Alloc Allocator type, defaults to allocator<Key>. 00099 * 00100 * @if maint 00101 * The private tree data is declared exactly the same way for set and 00102 * multiset; the distinction is made entirely in how the tree functions are 00103 * called (*_unique versus *_equal, same as the standard). 00104 * @endif 00105 */ 00106 template<class _Key, class _Compare, class _Alloc> 00107 class set 00108 { 00109 // concept requirements 00110 typedef typename _Alloc::value_type _Alloc_value_type; 00111 __glibcxx_class_requires(_Key, _SGIAssignableConcept) 00112 __glibcxx_class_requires4(_Compare, bool, _Key, _Key, 00113 _BinaryFunctionConcept) 00114 __glibcxx_class_requires2(_Key, _Alloc_value_type, _SameTypeConcept) 00115 00116 public: 00117 // typedefs: 00118 //@{ 00119 /// Public typedefs. 00120 typedef _Key key_type; 00121 typedef _Key value_type; 00122 typedef _Compare key_compare; 00123 typedef _Compare value_compare; 00124 typedef _Alloc allocator_type; 00125 //@} 00126 00127 private: 00128 typedef typename _Alloc::template rebind<_Key>::other _Key_alloc_type; 00129 00130 typedef _Rb_tree<key_type, value_type, _Identity<value_type>, 00131 key_compare, _Key_alloc_type> _Rep_type; 00132 _Rep_type _M_t; // red-black tree representing set 00133 00134 public: 00135 //@{ 00136 /// Iterator-related typedefs. 00137 typedef typename _Key_alloc_type::pointer pointer; 00138 typedef typename _Key_alloc_type::const_pointer const_pointer; 00139 typedef typename _Key_alloc_type::reference reference; 00140 typedef typename _Key_alloc_type::const_reference const_reference; 00141 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00142 // DR 103. set::iterator is required to be modifiable, 00143 // but this allows modification of keys. 00144 typedef typename _Rep_type::const_iterator iterator; 00145 typedef typename _Rep_type::const_iterator const_iterator; 00146 typedef typename _Rep_type::const_reverse_iterator reverse_iterator; 00147 typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator; 00148 typedef typename _Rep_type::size_type size_type; 00149 typedef typename _Rep_type::difference_type difference_type; 00150 //@} 00151 00152 // allocation/deallocation 00153 /// Default constructor creates no elements. 00154 set() 00155 : _M_t(_Compare(), allocator_type()) {} 00156 00157 /** 00158 * @brief Default constructor creates no elements. 00159 * 00160 * @param comp Comparator to use. 00161 * @param a Allocator to use. 00162 */ 00163 explicit 00164 set(const _Compare& __comp, 00165 const allocator_type& __a = allocator_type()) 00166 : _M_t(__comp, __a) {} 00167 00168 /** 00169 * @brief Builds a %set from a range. 00170 * @param first An input iterator. 00171 * @param last An input iterator. 00172 * 00173 * Create a %set consisting of copies of the elements from [first,last). 00174 * This is linear in N if the range is already sorted, and NlogN 00175 * otherwise (where N is distance(first,last)). 00176 */ 00177 template<class _InputIterator> 00178 set(_InputIterator __first, _InputIterator __last) 00179 : _M_t(_Compare(), allocator_type()) 00180 { _M_t.insert_unique(__first, __last); } 00181 00182 /** 00183 * @brief Builds a %set from a range. 00184 * @param first An input iterator. 00185 * @param last An input iterator. 00186 * @param comp A comparison functor. 00187 * @param a An allocator object. 00188 * 00189 * Create a %set consisting of copies of the elements from [first,last). 00190 * This is linear in N if the range is already sorted, and NlogN 00191 * otherwise (where N is distance(first,last)). 00192 */ 00193 template<class _InputIterator> 00194 set(_InputIterator __first, _InputIterator __last, 00195 const _Compare& __comp, 00196 const allocator_type& __a = allocator_type()) 00197 : _M_t(__comp, __a) 00198 { _M_t.insert_unique(__first, __last); } 00199 00200 /** 00201 * @brief Set copy constructor. 00202 * @param x A %set of identical element and allocator types. 00203 * 00204 * The newly-created %set uses a copy of the allocation object used 00205 * by @a x. 00206 */ 00207 set(const set<_Key,_Compare,_Alloc>& __x) 00208 : _M_t(__x._M_t) { } 00209 00210 /** 00211 * @brief Set assignment operator. 00212 * @param x A %set of identical element and allocator types. 00213 * 00214 * All the elements of @a x are copied, but unlike the copy constructor, 00215 * the allocator object is not copied. 00216 */ 00217 set<_Key,_Compare,_Alloc>& 00218 operator=(const set<_Key, _Compare, _Alloc>& __x) 00219 { 00220 _M_t = __x._M_t; 00221 return *this; 00222 } 00223 00224 // accessors: 00225 00226 /// Returns the comparison object with which the %set was constructed. 00227 key_compare 00228 key_comp() const 00229 { return _M_t.key_comp(); } 00230 /// Returns the comparison object with which the %set was constructed. 00231 value_compare 00232 value_comp() const 00233 { return _M_t.key_comp(); } 00234 /// Returns the allocator object with which the %set was constructed. 00235 allocator_type 00236 get_allocator() const 00237 { return _M_t.get_allocator(); } 00238 00239 /** 00240 * Returns a read/write iterator that points to the first element in the 00241 * %set. Iteration is done in ascending order according to the keys. 00242 */ 00243 iterator 00244 begin() const 00245 { return _M_t.begin(); } 00246 00247 /** 00248 * Returns a read/write iterator that points one past the last element in 00249 * the %set. Iteration is done in ascending order according to the keys. 00250 */ 00251 iterator 00252 end() const 00253 { return _M_t.end(); } 00254 00255 /** 00256 * Returns a read/write reverse iterator that points to the last element 00257 * in the %set. Iteration is done in descending order according to the 00258 * keys. 00259 */ 00260 reverse_iterator 00261 rbegin() const 00262 { return _M_t.rbegin(); } 00263 00264 /** 00265 * Returns a read-only (constant) reverse iterator that points to the 00266 * last pair in the %map. Iteration is done in descending order 00267 * according to the keys. 00268 */ 00269 reverse_iterator 00270 rend() const 00271 { return _M_t.rend(); } 00272 00273 /// Returns true if the %set is empty. 00274 bool 00275 empty() const 00276 { return _M_t.empty(); } 00277 00278 /// Returns the size of the %set. 00279 size_type 00280 size() const 00281 { return _M_t.size(); } 00282 00283 /// Returns the maximum size of the %set. 00284 size_type 00285 max_size() const 00286 { return _M_t.max_size(); } 00287 00288 /** 00289 * @brief Swaps data with another %set. 00290 * @param x A %set of the same element and allocator types. 00291 * 00292 * This exchanges the elements between two sets in constant time. 00293 * (It is only swapping a pointer, an integer, and an instance of 00294 * the @c Compare type (which itself is often stateless and empty), so it 00295 * should be quite fast.) 00296 * Note that the global std::swap() function is specialized such that 00297 * std::swap(s1,s2) will feed to this function. 00298 */ 00299 void 00300 swap(set<_Key,_Compare,_Alloc>& __x) 00301 { _M_t.swap(__x._M_t); } 00302 00303 // insert/erase 00304 /** 00305 * @brief Attempts to insert an element into the %set. 00306 * @param x Element to be inserted. 00307 * @return A pair, of which the first element is an iterator that points 00308 * to the possibly inserted element, and the second is a bool 00309 * that is true if the element was actually inserted. 00310 * 00311 * This function attempts to insert an element into the %set. A %set 00312 * relies on unique keys and thus an element is only inserted if it is 00313 * not already present in the %set. 00314 * 00315 * Insertion requires logarithmic time. 00316 */ 00317 std::pair<iterator,bool> 00318 insert(const value_type& __x) 00319 { 00320 std::pair<typename _Rep_type::iterator, bool> __p = 00321 _M_t.insert_unique(__x); 00322 return std::pair<iterator, bool>(__p.first, __p.second); 00323 } 00324 00325 /** 00326 * @brief Attempts to insert an element into the %set. 00327 * @param position An iterator that serves as a hint as to where the 00328 * element should be inserted. 00329 * @param x Element to be inserted. 00330 * @return An iterator that points to the element with key of @a x (may 00331 * or may not be the element passed in). 00332 * 00333 * This function is not concerned about whether the insertion took place, 00334 * and thus does not return a boolean like the single-argument insert() 00335 * does. Note that the first parameter is only a hint and can 00336 * potentially improve the performance of the insertion process. A bad 00337 * hint would cause no gains in efficiency. 00338 * 00339 * See http://gcc.gnu.org/onlinedocs/libstdc++/23_containers/howto.html#4 00340 * for more on "hinting". 00341 * 00342 * Insertion requires logarithmic time (if the hint is not taken). 00343 */ 00344 iterator 00345 insert(iterator __position, const value_type& __x) 00346 { return _M_t.insert_unique(__position, __x); } 00347 00348 /** 00349 * @brief A template function that attemps to insert a range of elements. 00350 * @param first Iterator pointing to the start of the range to be 00351 * inserted. 00352 * @param last Iterator pointing to the end of the range. 00353 * 00354 * Complexity similar to that of the range constructor. 00355 */ 00356 template<class _InputIterator> 00357 void 00358 insert(_InputIterator __first, _InputIterator __last) 00359 { _M_t.insert_unique(__first, __last); } 00360 00361 /** 00362 * @brief Erases an element from a %set. 00363 * @param position An iterator pointing to the element to be erased. 00364 * 00365 * This function erases an element, pointed to by the given iterator, 00366 * from a %set. Note that this function only erases the element, and 00367 * that if the element is itself a pointer, the pointed-to memory is not 00368 * touched in any way. Managing the pointer is the user's responsibilty. 00369 */ 00370 void 00371 erase(iterator __position) 00372 { _M_t.erase(__position); } 00373 00374 /** 00375 * @brief Erases elements according to the provided key. 00376 * @param x Key of element to be erased. 00377 * @return The number of elements erased. 00378 * 00379 * This function erases all the elements located by the given key from 00380 * a %set. 00381 * Note that this function only erases the element, and that if 00382 * the element is itself a pointer, the pointed-to memory is not touched 00383 * in any way. Managing the pointer is the user's responsibilty. 00384 */ 00385 size_type 00386 erase(const key_type& __x) 00387 { return _M_t.erase(__x); } 00388 00389 /** 00390 * @brief Erases a [first,last) range of elements from a %set. 00391 * @param first Iterator pointing to the start of the range to be 00392 * erased. 00393 * @param last Iterator pointing to the end of the range to be erased. 00394 * 00395 * This function erases a sequence of elements from a %set. 00396 * Note that this function only erases the element, and that if 00397 * the element is itself a pointer, the pointed-to memory is not touched 00398 * in any way. Managing the pointer is the user's responsibilty. 00399 */ 00400 void 00401 erase(iterator __first, iterator __last) 00402 { _M_t.erase(__first, __last); } 00403 00404 /** 00405 * Erases all elements in a %set. Note that this function only erases 00406 * the elements, and that if the elements themselves are pointers, the 00407 * pointed-to memory is not touched in any way. Managing the pointer is 00408 * the user's responsibilty. 00409 */ 00410 void 00411 clear() 00412 { _M_t.clear(); } 00413 00414 // set operations: 00415 00416 /** 00417 * @brief Finds the number of elements. 00418 * @param x Element to located. 00419 * @return Number of elements with specified key. 00420 * 00421 * This function only makes sense for multisets; for set the result will 00422 * either be 0 (not present) or 1 (present). 00423 */ 00424 size_type 00425 count(const key_type& __x) const 00426 { return _M_t.find(__x) == _M_t.end() ? 0 : 1; } 00427 00428 // _GLIBCXX_RESOLVE_LIB_DEFECTS 00429 // 214. set::find() missing const overload 00430 //@{ 00431 /** 00432 * @brief Tries to locate an element in a %set. 00433 * @param x Element to be located. 00434 * @return Iterator pointing to sought-after element, or end() if not 00435 * found. 00436 * 00437 * This function takes a key and tries to locate the element with which 00438 * the key matches. If successful the function returns an iterator 00439 * pointing to the sought after element. If unsuccessful it returns the 00440 * past-the-end ( @c end() ) iterator. 00441 */ 00442 iterator 00443 find(const key_type& __x) 00444 { return _M_t.find(__x); } 00445 00446 const_iterator 00447 find(const key_type& __x) const 00448 { return _M_t.find(__x); } 00449 //@} 00450 00451 //@{ 00452 /** 00453 * @brief Finds the beginning of a subsequence matching given key. 00454 * @param x Key to be located. 00455 * @return Iterator pointing to first element equal to or greater 00456 * than key, or end(). 00457 * 00458 * This function returns the first element of a subsequence of elements 00459 * that matches the given key. If unsuccessful it returns an iterator 00460 * pointing to the first element that has a greater value than given key 00461 * or end() if no such element exists. 00462 */ 00463 iterator 00464 lower_bound(const key_type& __x) 00465 { return _M_t.lower_bound(__x); } 00466 00467 const_iterator 00468 lower_bound(const key_type& __x) const 00469 { return _M_t.lower_bound(__x); } 00470 //@} 00471 00472 //@{ 00473 /** 00474 * @brief Finds the end of a subsequence matching given key. 00475 * @param x Key to be located. 00476 * @return Iterator pointing to the first element 00477 * greater than key, or end(). 00478 */ 00479 iterator 00480 upper_bound(const key_type& __x) 00481 { return _M_t.upper_bound(__x); } 00482 00483 const_iterator 00484 upper_bound(const key_type& __x) const 00485 { return _M_t.upper_bound(__x); } 00486 //@} 00487 00488 //@{ 00489 /** 00490 * @brief Finds a subsequence matching given key. 00491 * @param x Key to be located. 00492 * @return Pair of iterators that possibly points to the subsequence 00493 * matching given key. 00494 * 00495 * This function is equivalent to 00496 * @code 00497 * std::make_pair(c.lower_bound(val), 00498 * c.upper_bound(val)) 00499 * @endcode 00500 * (but is faster than making the calls separately). 00501 * 00502 * This function probably only makes sense for multisets. 00503 */ 00504 std::pair<iterator, iterator> 00505 equal_range(const key_type& __x) 00506 { return _M_t.equal_range(__x); } 00507 00508 std::pair<const_iterator, const_iterator> 00509 equal_range(const key_type& __x) const 00510 { return _M_t.equal_range(__x); } 00511 //@} 00512 00513 template<class _K1, class _C1, class _A1> 00514 friend bool 00515 operator== (const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&); 00516 00517 template<class _K1, class _C1, class _A1> 00518 friend bool 00519 operator< (const set<_K1, _C1, _A1>&, const set<_K1, _C1, _A1>&); 00520 }; 00521 00522 00523 /** 00524 * @brief Set equality comparison. 00525 * @param x A %set. 00526 * @param y A %set of the same type as @a x. 00527 * @return True iff the size and elements of the sets are equal. 00528 * 00529 * This is an equivalence relation. It is linear in the size of the sets. 00530 * Sets are considered equivalent if their sizes are equal, and if 00531 * corresponding elements compare equal. 00532 */ 00533 template<class _Key, class _Compare, class _Alloc> 00534 inline bool 00535 operator==(const set<_Key, _Compare, _Alloc>& __x, 00536 const set<_Key, _Compare, _Alloc>& __y) 00537 { return __x._M_t == __y._M_t; } 00538 00539 /** 00540 * @brief Set ordering relation. 00541 * @param x A %set. 00542 * @param y A %set of the same type as @a x. 00543 * @return True iff @a x is lexicographically less than @a y. 00544 * 00545 * This is a total ordering relation. It is linear in the size of the 00546 * maps. The elements must be comparable with @c <. 00547 * 00548 * See std::lexicographical_compare() for how the determination is made. 00549 */ 00550 template<class _Key, class _Compare, class _Alloc> 00551 inline bool 00552 operator<(const set<_Key, _Compare, _Alloc>& __x, 00553 const set<_Key, _Compare, _Alloc>& __y) 00554 { return __x._M_t < __y._M_t; } 00555 00556 /// Returns !(x == y). 00557 template<class _Key, class _Compare, class _Alloc> 00558 inline bool 00559 operator!=(const set<_Key, _Compare, _Alloc>& __x, 00560 const set<_Key, _Compare, _Alloc>& __y) 00561 { return !(__x == __y); } 00562 00563 /// Returns y < x. 00564 template<class _Key, class _Compare, class _Alloc> 00565 inline bool 00566 operator>(const set<_Key, _Compare, _Alloc>& __x, 00567 const set<_Key, _Compare, _Alloc>& __y) 00568 { return __y < __x; } 00569 00570 /// Returns !(y < x) 00571 template<class _Key, class _Compare, class _Alloc> 00572 inline bool 00573 operator<=(const set<_Key, _Compare, _Alloc>& __x, 00574 const set<_Key, _Compare, _Alloc>& __y) 00575 { return !(__y < __x); } 00576 00577 /// Returns !(x < y) 00578 template<class _Key, class _Compare, class _Alloc> 00579 inline bool 00580 operator>=(const set<_Key, _Compare, _Alloc>& __x, 00581 const set<_Key, _Compare, _Alloc>& __y) 00582 { return !(__x < __y); } 00583 00584 /// See std::set::swap(). 00585 template<class _Key, class _Compare, class _Alloc> 00586 inline void 00587 swap(set<_Key, _Compare, _Alloc>& __x, set<_Key, _Compare, _Alloc>& __y) 00588 { __x.swap(__y); } 00589 00590 } // namespace std 00591 00592 #endif /* _SET_H */