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      1 // -*- C++ -*-
      2 
      3 // Copyright (C) 2005-2013 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 sample_resize_policy.hpp
     38  * Contains a sample resize policy for hash tables.
     39  */
     40 
     41 #ifndef PB_DS_SAMPLE_RESIZE_POLICY_HPP
     42 #define PB_DS_SAMPLE_RESIZE_POLICY_HPP
     43 
     44 namespace __gnu_pbds
     45 {
     46   /// A sample resize policy.
     47   class sample_resize_policy
     48   {
     49   public:
     50     /// Size type.
     51     typedef std::size_t size_type;
     52 
     53     /// Default constructor.
     54     sample_resize_policy();
     55 
     56     /// Copy constructor.
     57     sample_range_hashing(const sample_resize_policy& other);
     58 
     59     /// Swaps content.
     60     inline void
     61     swap(sample_resize_policy& other);
     62 
     63   protected:
     64     /// Notifies a search started.
     65     inline void
     66     notify_insert_search_start();
     67 
     68     /// Notifies a search encountered a collision.
     69     inline void
     70     notify_insert_search_collision();
     71 
     72     /// Notifies a search ended.
     73     inline void
     74     notify_insert_search_end();
     75 
     76     /// Notifies a search started.
     77     inline void
     78     notify_find_search_start();
     79 
     80     /// Notifies a search encountered a collision.
     81     inline void
     82     notify_find_search_collision();
     83 
     84     /// Notifies a search ended.
     85     inline void
     86     notify_find_search_end();
     87 
     88     /// Notifies a search started.
     89     inline void
     90     notify_erase_search_start();
     91 
     92     /// Notifies a search encountered a collision.
     93     inline void
     94     notify_erase_search_collision();
     95 
     96     /// Notifies a search ended.
     97     inline void
     98     notify_erase_search_end();
     99 
    100     /// Notifies an element was inserted.
    101     inline void
    102     notify_inserted(size_type num_e);
    103 
    104     /// Notifies an element was erased.
    105     inline void
    106     notify_erased(size_type num_e);
    107 
    108     /// Notifies the table was cleared.
    109     void
    110     notify_cleared();
    111 
    112     /// Notifies the table was resized to new_size.
    113     void
    114     notify_resized(size_type new_size);
    115 
    116     /// Queries whether a resize is needed.
    117     inline bool
    118     is_resize_needed() const;
    119 
    120     /// Queries what the new size should be.
    121     size_type
    122     get_new_size(size_type size, size_type num_used_e) const;
    123   };
    124 }
    125 #endif
    126