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The C and C++ Include Header Files

cat -n /usr/include/c++/15/ext/pb_ds/detail/list_update_policy/lu_counter_metadata.hpp

     1	// -*- C++ -*-
     2	
     3	// Copyright (C) 2005-2025 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 lu_counter_metadata.hpp
    38	 * Contains implementation of a lu counter policy's metadata.
    39	 */
    40	
    41	namespace __gnu_pbds
    42	{
    43	  namespace detail
    44	  {
    45	    template<typename Size_Type>
    46	      class lu_counter_policy_base;
    47	
    48	    /// A list-update metadata type that moves elements to the front of
    49	    /// the list based on the counter algorithm.
    50	    template<typename Size_Type = std::size_t>
    51	      class lu_counter_metadata
    52	      {
    53	      public:
    54		typedef Size_Type 	size_type;
    55	
    56	      private:
    57		lu_counter_metadata(size_type init_count) : m_count(init_count)
    58		{ }
    59	
    60		friend class lu_counter_policy_base<size_type>;
    61	
    62		mutable size_type 	m_count;
    63	    };
    64	
    65	    /// Base class for list-update counter policy.
    66	    template<typename Size_Type>
    67	      class lu_counter_policy_base
    68	      {
    69	      protected:
    70		typedef Size_Type 	size_type;
    71	
    72		lu_counter_metadata<size_type>
    73		operator()(size_type max_size) const
    74		{ return lu_counter_metadata<Size_Type>(std::rand() % max_size); }
    75	
    76		template<typename Metadata_Reference>
    77		bool
    78		operator()(Metadata_Reference r_data, size_type m_max_count) const
    79		{
    80		  if (++r_data.m_count != m_max_count)
    81		    return false;
    82		  r_data.m_count = 0;
    83		  return true;
    84		}
    85	      };
    86	  } // namespace detail
    87	} // namespace __gnu_pbds