text: // -*- C++ -*-
  
  // Copyright (C) 2005-2016 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 tree_policy/order_statistics_imp.hpp
   * Contains forward declarations for order_statistics_key
   */
  
  PB_DS_CLASS_T_DEC
  inline typename PB_DS_CLASS_C_DEC::iterator
  PB_DS_CLASS_C_DEC::
  find_by_order(size_type order)
  {
    node_iterator it = node_begin();
    node_iterator end_it = node_end();
  
    while (it != end_it)
      {
        node_iterator l_it = it.get_l_child();
        const size_type o = (l_it == end_it)? 0 : l_it.get_metadata();
  
        if (order == o)
  	return *it;
        else if (order < o)
  	it = l_it;
        else
          {
  	  order -= o + 1;
  	  it = it.get_r_child();
          }
      }
  
    return base_type::end_iterator();
  }
  
  PB_DS_CLASS_T_DEC
  inline typename PB_DS_CLASS_C_DEC::const_iterator
  PB_DS_CLASS_C_DEC::
  find_by_order(size_type order) const
  { return const_cast<PB_DS_CLASS_C_DEC*>(this)->find_by_order(order); }
  
  PB_DS_CLASS_T_DEC
  inline typename PB_DS_CLASS_C_DEC::size_type
  PB_DS_CLASS_C_DEC::
  order_of_key(key_const_reference r_key) const
  {
    node_const_iterator it = node_begin();
    node_const_iterator end_it = node_end();
  
    const cmp_fn& r_cmp_fn = const_cast<PB_DS_CLASS_C_DEC*>(this)->get_cmp_fn();
    size_type ord = 0;
    while (it != end_it)
      {
        node_const_iterator l_it = it.get_l_child();
  
        if (r_cmp_fn(r_key, this->extract_key(*(*it))))
  	it = l_it;
        else if (r_cmp_fn(this->extract_key(*(*it)), r_key))
          {
  	  ord += (l_it == end_it)? 1 : 1 + l_it.get_metadata();
  	  it = it.get_r_child();
          }
        else
          {
  	  ord += (l_it == end_it)? 0 : l_it.get_metadata();
  	  it = end_it;
          }
      }
    return ord;
  }
  
  PB_DS_CLASS_T_DEC
  inline void
  PB_DS_CLASS_C_DEC::
  operator()(node_iterator node_it, node_const_iterator end_nd_it) const
  {
    node_iterator l_it = node_it.get_l_child();
    const size_type l_rank = (l_it == end_nd_it) ? 0 : l_it.get_metadata();
  
    node_iterator r_it = node_it.get_r_child();
    const size_type r_rank = (r_it == end_nd_it) ? 0 : r_it.get_metadata();
  
    const_cast<metadata_reference>(node_it.get_metadata())= 1 + l_rank + r_rank;
  }
  
  PB_DS_CLASS_T_DEC
  PB_DS_CLASS_C_DEC::
  ~tree_order_statistics_node_update()
  { }
  