libstdc++
mod_based_range_hashing.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2020 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.
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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
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24 
25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
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27 // Permission to use, copy, modify, sell, and distribute this software
28 // is hereby granted without fee, provided that the above copyright
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35 
36 /**
37  * @file mod_based_range_hashing.hpp
38  * Contains a range hashing policy base.
39  */
40 
41 #ifndef PB_DS_MOD_BASED_RANGE_HASHING_HPP
42 #define PB_DS_MOD_BASED_RANGE_HASHING_HPP
43 
44 namespace __gnu_pbds
45 {
46  namespace detail
47  {
48  /// Mod based range hashing.
49  template<typename Size_Type>
51  {
52  protected:
53  typedef Size_Type size_type;
54 
55  void
56  swap(mod_based_range_hashing& other)
57  { std::swap(m_size, other.m_size); }
58 
59  void
60  notify_resized(size_type s)
61  { m_size = s; }
62 
63  inline size_type
64  range_hash(size_type s) const
65  { return s % m_size; }
66 
67  private:
68  size_type m_size;
69  };
70  } // namespace detail
71 
72 } // namespace __gnu_pbds
73 
74 #endif // #ifndef PB_DS_MOD_BASED_RANGE_HASHING_HPP
GNU extensions for policy-based data structures for public use.