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      1 // -*- C++ -*-
      2 
      3 // Copyright (C) 2005, 2006, 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/order_statistics_imp.hpp
     38  * Contains forward declarations for order_statistics_key
     39  */
     40 
     41 PB_DS_CLASS_T_DEC
     42 inline typename PB_DS_CLASS_C_DEC::iterator
     43 PB_DS_CLASS_C_DEC::
     44 find_by_order(size_type order)
     45 {
     46   if (empty())
     47     return end();
     48 
     49   ++order;
     50   node_iterator nd_it = node_begin();
     51 
     52   while (true)
     53     {
     54       if (order > nd_it.get_metadata())
     55 	return ++base_type::rightmost_it(nd_it);
     56 
     57       const size_type num_children = nd_it.num_children();
     58       if (num_children == 0)
     59 	return *nd_it;
     60 
     61       for (size_type i = 0; i < num_children; ++i)
     62 	{
     63 	  node_iterator child_nd_it = nd_it.get_child(i);
     64 	  if (order <= child_nd_it.get_metadata())
     65 	    {
     66 	      i = num_children;
     67 	      nd_it = child_nd_it;
     68 	    }
     69 	  else
     70 	    order -= child_nd_it.get_metadata();
     71 	}
     72     }
     73 }
     74 
     75 PB_DS_CLASS_T_DEC
     76 inline typename PB_DS_CLASS_C_DEC::const_iterator
     77 PB_DS_CLASS_C_DEC::
     78 find_by_order(size_type order) const
     79 { return const_cast<PB_DS_CLASS_C_DEC*>(this)->find_by_order(order); }
     80 
     81 PB_DS_CLASS_T_DEC
     82 inline typename PB_DS_CLASS_C_DEC::size_type
     83 PB_DS_CLASS_C_DEC::
     84 order_of_key(key_const_reference r_key) const
     85 {
     86   const _ATraits& r_traits =
     87     const_cast<PB_DS_CLASS_C_DEC* >(this)->get_access_traits();
     88 
     89   return order_of_prefix(r_traits.begin(r_key), r_traits.end(r_key));
     90 }
     91 
     92 PB_DS_CLASS_T_DEC
     93 inline typename PB_DS_CLASS_C_DEC::size_type
     94 PB_DS_CLASS_C_DEC::
     95 order_of_prefix(typename access_traits::const_iterator b,
     96 		typename access_traits::const_iterator e) const
     97 {
     98   if (empty())
     99     return 0;
    100 
    101   const _ATraits& r_traits =
    102     const_cast<PB_DS_CLASS_C_DEC*>(this)->get_access_traits();
    103 
    104   node_const_iterator nd_it = node_begin();
    105   node_const_iterator end_nd_it = node_end();
    106   size_type ord = 0;
    107 
    108   while (true)
    109     {
    110       const size_type num_children = nd_it.num_children();
    111       if (num_children == 0)
    112 	{
    113 	  key_const_reference r_key = base_type::extract_key(*(*nd_it));
    114 	  typename access_traits::const_iterator key_b =
    115 	    r_traits.begin(r_key);
    116 
    117 	  typename access_traits::const_iterator key_e =
    118 	    r_traits.end(r_key);
    119 
    120 	  return (base_type::less(key_b, key_e,  b, e,  r_traits)) ?
    121 		  ord + 1 : ord;
    122 	}
    123 
    124       node_const_iterator next_nd_it = end_nd_it;
    125       size_type i = num_children - 1;
    126 
    127       do
    128 	{
    129 	  node_const_iterator child_nd_it = nd_it.get_child(i);
    130 
    131 	  if (next_nd_it != end_nd_it)
    132 	    ord += child_nd_it.get_metadata();
    133 	  else if (!base_type::less(b, e,
    134 				    child_nd_it.valid_prefix().first,
    135 				    child_nd_it.valid_prefix().second,
    136 				    r_traits))
    137 	    next_nd_it = child_nd_it;
    138 	}
    139       while (i-- > 0);
    140 
    141       if (next_nd_it == end_nd_it)
    142 	return ord;
    143 
    144       nd_it = next_nd_it;
    145     }
    146 }
    147 
    148 PB_DS_CLASS_T_DEC
    149 inline void
    150 PB_DS_CLASS_C_DEC::
    151 operator()(node_iterator nd_it, node_const_iterator /*end_nd_it*/) const
    152 {
    153   const size_type num_children = nd_it.num_children();
    154   size_type children_rank = 0;
    155   for (size_type i = 0; i < num_children; ++i)
    156     children_rank += nd_it.get_child(i).get_metadata();
    157 
    158   const size_type res = (num_children == 0) ? 1 : children_rank;
    159   const_cast<size_type&>(nd_it.get_metadata()) = res;
    160 }
    161