libstdc++-v3/include/ext/pb_ds/detail/left_child_next_sibling_heap_/const_iterator.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2014 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 left_child_next_sibling_heap_/const_iterator.hpp
  38  * Contains an iterator class returned by the table's const find and insert
  39  * methods.
  40  */
  41
  42 #ifndef PB_DS_LEFT_CHILD_NEXT_SIBLING_HEAP_CONST_ITERATOR_HPP
  43 #define PB_DS_LEFT_CHILD_NEXT_SIBLING_HEAP_CONST_ITERATOR_HPP
  44
  45 #include <ext/pb_ds/detail/left_child_next_sibling_heap_/point_const_iterator.hpp>
  46 #include <debug/debug.h>
  47
  48 namespace __gnu_pbds
  49 {
  50   namespace detail
  51   {
  52 #define PB_DS_CLASS_C_DEC  \
  53     left_child_next_sibling_heap_const_iterator_<Node, _Alloc>
  54
  55 #define PB_DS_BASIC_HEAP_CIT_BASE \
  56     left_child_next_sibling_heap_node_point_const_iterator_<Node, _Alloc>
  57
  58     /// Const point-type iterator.
  59     template<typename Node, typename _Alloc>
  60     class left_child_next_sibling_heap_const_iterator_
  61     : public PB_DS_BASIC_HEAP_CIT_BASE
  62     {
  63     private:
  64       typedef PB_DS_BASIC_HEAP_CIT_BASE                 base_type;
  65       typedef typename base_type::node_pointer          node_pointer;
  66
  67     public:
  68       /// Category.
  69       typedef std::forward_iterator_tag                 iterator_category;
  70
  71       /// Difference type.
  72       typedef typename _Alloc::difference_type          difference_type;
  73
  74       /// Iterator's value type.
  75       typedef typename base_type::value_type            value_type;
  76
  77       /// Iterator's pointer type.
  78       typedef typename base_type::pointer               pointer;
  79
  80       /// Iterator's const pointer type.
  81       typedef typename base_type::const_pointer         const_pointer;
  82
  83       /// Iterator's reference type.
  84       typedef typename base_type::reference             reference;
  85
  86       /// Iterator's const reference type.
  87       typedef typename base_type::const_reference       const_reference;
  88
  89       inline
  90       left_child_next_sibling_heap_const_iterator_(node_pointer p_nd)
  91       : base_type(p_nd)
  92       { }
  93
  94       /// Default constructor.
  95       inline
  96       left_child_next_sibling_heap_const_iterator_()
  97       { }
  98
  99       /// Copy constructor.
 100       inline
 101       left_child_next_sibling_heap_const_iterator_(const PB_DS_CLASS_C_DEC& other) : base_type(other)
 102       { }
 103
 104       /// Compares content to a different iterator object.
 105       bool
 106       operator==(const PB_DS_CLASS_C_DEC& other) const
 107       { return (base_type::m_p_nd == other.m_p_nd); }
 108
 109       /// Compares content (negatively) to a different iterator object.
 110       bool
 111       operator!=(const PB_DS_CLASS_C_DEC& other) const
 112       { return (base_type::m_p_nd != other.m_p_nd); }
 113
 114       PB_DS_CLASS_C_DEC&
 115       operator++()
 116       {
 117         _GLIBCXX_DEBUG_ASSERT(base_type::m_p_nd != 0);
 118         inc();
 119         return (*this);
 120       }
 121
 122       PB_DS_CLASS_C_DEC
 123       operator++(int)
 124       {
 125         PB_DS_CLASS_C_DEC ret_it(base_type::m_p_nd);
 126         operator++();
 127         return (ret_it);
 128       }
 129
 130     private:
 131       void
 132       inc()
 133       {
 134         if (base_type::m_p_nd->m_p_next_sibling != 0)
 135           {
 136             base_type::m_p_nd = base_type::m_p_nd->m_p_next_sibling;
 137             while (base_type::m_p_nd->m_p_l_child != 0)
 138               base_type::m_p_nd = base_type::m_p_nd->m_p_l_child;
 139             return;
 140           }
 141
 142         while (true)
 143           {
 144             node_pointer p_next = base_type::m_p_nd;
 145             base_type::m_p_nd = base_type::m_p_nd->m_p_prev_or_parent;
 146             if (base_type::m_p_nd == 0
 147                 || base_type::m_p_nd->m_p_l_child == p_next)
 148               return;
 149           }
 150       }
 151     };
 152
 153 #undef PB_DS_CLASS_C_DEC
 154 #undef PB_DS_BASIC_HEAP_CIT_BASE
 155
 156   } // namespace detail
 157 } // namespace __gnu_pbds
 158
 159 #endif