1 // -*- C++ -*- 2 3 // Copyright (C) 2005, 2006, 2007, 2009, 2010 Free Software Foundation, Inc. 4 // 5 // This file is part of the GNU ISO C++ Library. This library is free 6 // software; you can redistribute it and/or modify it under the terms 7 // of the GNU General Public License as published by the Free Software 8 // Foundation; either version 3, or (at your option) any later 9 // version. 10 11 // This library is distributed in the hope that it will be useful, but 12 // WITHOUT ANY WARRANTY; without even the implied warranty of 13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 // General Public License for more details. 15 16 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL. 26 27 // Permission to use, copy, modify, sell, and distribute this software 28 // is hereby granted without fee, provided that the above copyright 29 // notice appears in all copies, and that both that copyright notice 30 // and this permission notice appear in supporting documentation. None 31 // of the above authors, nor IBM Haifa Research Laboratories, make any 32 // representation about the suitability of this software for any 33 // purpose. It is provided "as is" without express or implied 34 // warranty. 35 36 /** 37 * @file trie_policy.hpp 38 * Contains trie-related policies. 39 */ 40 41 #ifndef PB_DS_TRIE_POLICY_HPP 42 #define PB_DS_TRIE_POLICY_HPP 43 44 #include <bits/c++config.h> 45 #include <string> 46 #include <ext/pb_ds/detail/type_utils.hpp> 47 #include <ext/pb_ds/detail/trie_policy/trie_policy_base.hpp> 48 49 namespace __gnu_pbds 50 { 51 // A null node updator, indicating that no node updates are required. 52 template<typename Const_Node_Iterator, 53 typename Node_Iterator, 54 typename E_Access_Traits, 55 typename Allocator> 56 struct null_trie_node_update 57 { }; 58 59 #define PB_DS_CLASS_T_DEC \ 60 template<typename String, typename String::value_type Min_E_Val, typename String::value_type Max_E_Val, bool Reverse, typename Allocator> 61 62 #define PB_DS_CLASS_C_DEC \ 63 string_trie_e_access_traits<String, Min_E_Val,Max_E_Val,Reverse,Allocator> 64 65 // Element access traits for string types. 66 template<typename String = std::string, 67 typename String::value_type Min_E_Val = detail::__numeric_traits<typename String::value_type>::__min, 68 typename String::value_type Max_E_Val = detail::__numeric_traits<typename String::value_type>::__max, 69 bool Reverse = false, 70 typename Allocator = std::allocator<char> > 71 struct string_trie_e_access_traits 72 { 73 public: 74 typedef typename Allocator::size_type size_type; 75 typedef String key_type; 76 typedef typename Allocator::template rebind<key_type>::other key_rebind; 77 typedef typename key_rebind::const_reference const_key_reference; 78 79 enum 80 { 81 reverse = Reverse 82 }; 83 84 // Element const iterator type. 85 typedef typename detail::__conditional_type<Reverse, typename String::const_reverse_iterator, typename String::const_iterator>::__type const_iterator; 86 87 // Element type. 88 typedef typename std::iterator_traits<const_iterator>::value_type e_type; 89 90 enum 91 { 92 min_e_val = Min_E_Val, 93 max_e_val = Max_E_Val, 94 max_size = max_e_val - min_e_val + 1 95 }; 96 PB_DS_STATIC_ASSERT(min_max_size, max_size >= 2); 97 98 // Returns a const_iterator to the first element of 99 // const_key_reference agumnet. 100 inline static const_iterator 101 begin(const_key_reference); 102 103 // Returns a const_iterator to the after-last element of 104 // const_key_reference argument. 105 inline static const_iterator 106 end(const_key_reference); 107 108 // Maps an element to a position. 109 inline static size_type 110 e_pos(e_type e); 111 112 private: 113 114 inline static const_iterator 115 begin_imp(const_key_reference, detail::false_type); 116 117 inline static const_iterator 118 begin_imp(const_key_reference, detail::true_type); 119 120 inline static const_iterator 121 end_imp(const_key_reference, detail::false_type); 122 123 inline static const_iterator 124 end_imp(const_key_reference, detail::true_type); 125 126 static detail::integral_constant<int, Reverse> s_rev_ind; 127 }; 128 129 #include <ext/pb_ds/detail/trie_policy/string_trie_e_access_traits_imp.hpp> 130 131 #undef PB_DS_CLASS_T_DEC 132 #undef PB_DS_CLASS_C_DEC 133 134 #define PB_DS_CLASS_T_DEC \ 135 template<typename Const_Node_Iterator,typename Node_Iterator,class E_Access_Traits, typename Allocator> 136 137 #define PB_DS_CLASS_C_DEC \ 138 trie_prefix_search_node_update<Const_Node_Iterator, Node_Iterator, E_Access_Traits,Allocator> 139 140 #define PB_DS_BASE_C_DEC \ 141 detail::trie_policy_base<Const_Node_Iterator,Node_Iterator,E_Access_Traits, Allocator> 142 143 // A node updator that allows tries to be searched for the range of 144 // values that match a certain prefix. 145 template<typename Const_Node_Iterator, 146 typename Node_Iterator, 147 typename E_Access_Traits, 148 typename Allocator> 149 class trie_prefix_search_node_update : private PB_DS_BASE_C_DEC 150 { 151 private: 152 typedef PB_DS_BASE_C_DEC base_type; 153 154 public: 155 typedef typename base_type::key_type key_type; 156 typedef typename base_type::const_key_reference const_key_reference; 157 158 // Element access traits. 159 typedef E_Access_Traits e_access_traits; 160 161 // Const element iterator. 162 typedef typename e_access_traits::const_iterator const_e_iterator; 163 164 // Allocator type. 165 typedef Allocator allocator_type; 166 167 // Size type. 168 typedef typename allocator_type::size_type size_type; 169 typedef detail::null_node_metadata metadata_type; 170 typedef Const_Node_Iterator const_node_iterator; 171 typedef Node_Iterator node_iterator; 172 typedef typename const_node_iterator::value_type const_iterator; 173 typedef typename node_iterator::value_type iterator; 174 175 // Finds the const iterator range corresponding to all values 176 // whose prefixes match r_key. 177 std::pair<const_iterator, const_iterator> 178 prefix_range(const_key_reference) const; 179 180 // Finds the iterator range corresponding to all values whose 181 // prefixes match r_key. 182 std::pair<iterator, iterator> 183 prefix_range(const_key_reference); 184 185 // Finds the const iterator range corresponding to all values 186 // whose prefixes match [b, e). 187 std::pair<const_iterator, const_iterator> 188 prefix_range(const_e_iterator, const_e_iterator) const; 189 190 // Finds the iterator range corresponding to all values whose 191 // prefixes match [b, e). 192 std::pair<iterator, iterator> 193 prefix_range(const_e_iterator, const_e_iterator); 194 195 protected: 196 // Called to update a node's metadata. 197 inline void 198 operator()(node_iterator node_it, const_node_iterator end_nd_it) const; 199 200 private: 201 // Returns the const iterator associated with the just-after last element. 202 virtual const_iterator 203 end() const = 0; 204 205 // Returns the iterator associated with the just-after last element. 206 virtual iterator 207 end() = 0; 208 209 // Returns the const_node_iterator associated with the trie's root node. 210 virtual const_node_iterator 211 node_begin() const = 0; 212 213 // Returns the node_iterator associated with the trie's root node. 214 virtual node_iterator 215 node_begin() = 0; 216 217 // Returns the const_node_iterator associated with a just-after leaf node. 218 virtual const_node_iterator 219 node_end() const = 0; 220 221 // Returns the node_iterator associated with a just-after leaf node. 222 virtual node_iterator 223 node_end() = 0; 224 225 // Access to the cmp_fn object. 226 virtual const e_access_traits& 227 get_e_access_traits() const = 0; 228 229 node_iterator 230 next_child(node_iterator, const_e_iterator, const_e_iterator, 231 node_iterator, const e_access_traits&); 232 }; 233 234 #include <ext/pb_ds/detail/trie_policy/prefix_search_node_update_imp.hpp> 235 236 #undef PB_DS_CLASS_C_DEC 237 238 #define PB_DS_CLASS_C_DEC \ 239 trie_order_statistics_node_update<Const_Node_Iterator, Node_Iterator,E_Access_Traits, Allocator> 240 241 // Functor updating ranks of entrees. 242 template<typename Const_Node_Iterator, 243 typename Node_Iterator, 244 typename E_Access_Traits, 245 typename Allocator> 246 class trie_order_statistics_node_update : private PB_DS_BASE_C_DEC 247 { 248 private: 249 typedef PB_DS_BASE_C_DEC base_type; 250 251 public: 252 typedef E_Access_Traits e_access_traits; 253 typedef typename e_access_traits::const_iterator const_e_iterator; 254 typedef Allocator allocator_type; 255 typedef typename allocator_type::size_type size_type; 256 typedef typename base_type::key_type key_type; 257 typedef typename base_type::const_key_reference const_key_reference; 258 259 typedef size_type metadata_type; 260 typedef Const_Node_Iterator const_node_iterator; 261 typedef Node_Iterator node_iterator; 262 typedef typename const_node_iterator::value_type const_iterator; 263 typedef typename node_iterator::value_type iterator; 264 265 // Finds an entry by __order. Returns a const_iterator to the 266 // entry with the __order order, or a const_iterator to the 267 // container object's end if order is at least the size of the 268 // container object. 269 inline const_iterator 270 find_by_order(size_type) const; 271 272 // Finds an entry by __order. Returns an iterator to the entry 273 // with the __order order, or an iterator to the container 274 // object's end if order is at least the size of the container 275 // object. 276 inline iterator 277 find_by_order(size_type); 278 279 // Returns the order of a key within a sequence. For exapmle, if 280 // r_key is the smallest key, this method will return 0; if r_key 281 // is a key between the smallest and next key, this method will 282 // return 1; if r_key is a key larger than the largest key, this 283 // method will return the size of r_c. 284 inline size_type 285 order_of_key(const_key_reference) const; 286 287 // Returns the order of a prefix within a sequence. For exapmle, 288 // if [b, e] is the smallest prefix, this method will return 0; if 289 // r_key is a key between the smallest and next key, this method 290 // will return 1; if r_key is a key larger than the largest key, 291 // this method will return the size of r_c. 292 inline size_type 293 order_of_prefix(const_e_iterator, const_e_iterator) const; 294 295 private: 296 typedef typename base_type::const_reference const_reference; 297 typedef typename base_type::const_pointer const_pointer; 298 299 typedef typename Allocator::template rebind<metadata_type>::other metadata_rebind; 300 typedef typename metadata_rebind::const_reference const_metadata_reference; 301 typedef typename metadata_rebind::reference metadata_reference; 302 303 // Returns true if the container is empty. 304 virtual bool 305 empty() const = 0; 306 307 // Returns the iterator associated with the trie's first element. 308 virtual iterator 309 begin() = 0; 310 311 // Returns the iterator associated with the trie's 312 // just-after-last element. 313 virtual iterator 314 end() = 0; 315 316 // Returns the const_node_iterator associated with the trie's root node. 317 virtual const_node_iterator 318 node_begin() const = 0; 319 320 // Returns the node_iterator associated with the trie's root node. 321 virtual node_iterator 322 node_begin() = 0; 323 324 // Returns the const_node_iterator associated with a just-after 325 // leaf node. 326 virtual const_node_iterator 327 node_end() const = 0; 328 329 // Returns the node_iterator associated with a just-after leaf node. 330 virtual node_iterator 331 node_end() = 0; 332 333 // Access to the cmp_fn object. 334 virtual e_access_traits& 335 get_e_access_traits() = 0; 336 337 protected: 338 // Updates the rank of a node through a node_iterator node_it; 339 // end_nd_it is the end node iterator. 340 inline void 341 operator()(node_iterator, const_node_iterator) const; 342 343 // Destructor. 344 virtual 345 ~trie_order_statistics_node_update(); 346 }; 347 348 #include <ext/pb_ds/detail/trie_policy/order_statistics_imp.hpp> 349 350 #undef PB_DS_CLASS_T_DEC 351 #undef PB_DS_CLASS_C_DEC 352 #undef PB_DS_BASE_C_DEC 353 354 } // namespace __gnu_pbds 355 356 #endif 357