Edit File: trie_policy_base.hpp
// -*- C++ -*- // Copyright (C) 2005-2018 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the terms // of the GNU General Public License as published by the Free Software // Foundation; either version 3, or (at your option) any later // version. // This library is distributed in the hope that it will be useful, but // WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // General Public License for more details. // Under Section 7 of GPL version 3, you are granted additional // permissions described in the GCC Runtime Library Exception, version // 3.1, as published by the Free Software Foundation. // You should have received a copy of the GNU General Public License and // a copy of the GCC Runtime Library Exception along with this program; // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see // <http://www.gnu.org/licenses/>. // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL. // Permission to use, copy, modify, sell, and distribute this software // is hereby granted without fee, provided that the above copyright // notice appears in all copies, and that both that copyright notice // and this permission notice appear in supporting documentation. None // of the above authors, nor IBM Haifa Research Laboratories, make any // representation about the suitability of this software for any // purpose. It is provided "as is" without express or implied // warranty. /** * @file trie_policy/trie_policy_base.hpp * Contains an implementation of trie_policy_base. */ #ifndef PB_DS_TRIE_POLICY_BASE_HPP #define PB_DS_TRIE_POLICY_BASE_HPP #include <ext/pb_ds/detail/branch_policy/branch_policy.hpp> namespace __gnu_pbds { namespace detail { /// Base class for trie policies. template<typename Node_CItr, typename Node_Itr, typename _ATraits, typename _Alloc> class trie_policy_base : public branch_policy<Node_CItr, Node_Itr, _Alloc> { typedef branch_policy<Node_CItr, Node_Itr, _Alloc> base_type; public: typedef _ATraits access_traits; typedef _Alloc allocator_type; typedef typename allocator_type::size_type size_type; typedef null_type metadata_type; typedef Node_CItr node_const_iterator; typedef Node_Itr node_iterator; typedef typename node_const_iterator::value_type const_iterator; typedef typename node_iterator::value_type iterator; typedef typename base_type::key_type key_type; typedef typename base_type::key_const_reference key_const_reference; protected: virtual const_iterator end() const = 0; virtual iterator end() = 0; virtual node_const_iterator node_begin() const = 0; virtual node_iterator node_begin() = 0; virtual node_const_iterator node_end() const = 0; virtual node_iterator node_end() = 0; virtual const access_traits& get_access_traits() const = 0; private: typedef typename access_traits::const_iterator e_const_iterator; typedef std::pair<e_const_iterator, e_const_iterator> prefix_range_t; protected: static size_type common_prefix_len(node_iterator, e_const_iterator, e_const_iterator, const access_traits&); static iterator leftmost_it(node_iterator); static iterator rightmost_it(node_iterator); static bool less(e_const_iterator, e_const_iterator, e_const_iterator, e_const_iterator, const access_traits&); }; #define PB_DS_CLASS_T_DEC \ template<typename Node_CItr, typename Node_Itr, \ typename _ATraits, typename _Alloc> #define PB_DS_CLASS_C_DEC \ trie_policy_base<Node_CItr, Node_Itr, _ATraits, _Alloc> PB_DS_CLASS_T_DEC typename PB_DS_CLASS_C_DEC::size_type PB_DS_CLASS_C_DEC:: common_prefix_len(node_iterator nd_it, e_const_iterator b_r, e_const_iterator e_r, const access_traits& r_traits) { prefix_range_t pref_range = nd_it.valid_prefix(); e_const_iterator b_l = pref_range.first; e_const_iterator e_l = pref_range.second; const size_type range_length_l = std::distance(b_l, e_l); const size_type range_length_r = std::distance(b_r, e_r); if (range_length_r < range_length_l) { std::swap(b_l, b_r); std::swap(e_l, e_r); } size_type ret = 0; while (b_l != e_l) { if (r_traits.e_pos(*b_l) != r_traits.e_pos(*b_r)) return ret; ++ret; ++b_l; ++b_r; } return ret; } PB_DS_CLASS_T_DEC typename PB_DS_CLASS_C_DEC::iterator PB_DS_CLASS_C_DEC:: leftmost_it(node_iterator nd_it) { if (nd_it.num_children() == 0) return *nd_it; return leftmost_it(nd_it.get_child(0)); } PB_DS_CLASS_T_DEC typename PB_DS_CLASS_C_DEC::iterator PB_DS_CLASS_C_DEC:: rightmost_it(node_iterator nd_it) { const size_type num_children = nd_it.num_children(); if (num_children == 0) return *nd_it; return rightmost_it(nd_it.get_child(num_children - 1)); } PB_DS_CLASS_T_DEC bool PB_DS_CLASS_C_DEC:: less(e_const_iterator b_l, e_const_iterator e_l, e_const_iterator b_r, e_const_iterator e_r, const access_traits& r_traits) { while (b_l != e_l) { if (b_r == e_r) return false; size_type l_pos = r_traits.e_pos(*b_l); size_type r_pos = r_traits.e_pos(*b_r); if (l_pos != r_pos) return (l_pos < r_pos); ++b_l; ++b_r; } return b_r != e_r; } #undef PB_DS_CLASS_T_DEC #undef PB_DS_CLASS_C_DEC } // namespace detail } // namespace __gnu_pbds #endif // #ifndef PB_DS_TRIE_POLICY_BASE_HPP