1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
// -*- C++ -*-
// Copyright (C) 2005, 2006, 2007, 2009 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 counter_lu_metadata.hpp
* Contains implementation of a lu counter policy's metadata.
*/
namespace __gnu_pbds
{
namespace detail
{
template<typename Size_Type>
class counter_lu_policy_base;
// A list-update metadata type that moves elements to the front of
// the list based on the counter algorithm.
template<typename Size_Type = size_t>
class counter_lu_metadata
{
public:
typedef Size_Type size_type;
private:
counter_lu_metadata(size_type init_count) : m_count(init_count)
{ }
friend class counter_lu_policy_base<size_type>;
mutable size_type m_count;
};
template<typename Size_Type>
class counter_lu_policy_base
{
protected:
typedef Size_Type size_type;
counter_lu_metadata<size_type>
operator()(size_type max_size) const
{ return counter_lu_metadata<Size_Type>(std::rand() % max_size); }
template<typename Metadata_Reference>
bool
operator()(Metadata_Reference r_data, size_type m_max_count) const
{
if (++r_data.m_count != m_max_count)
return false;
r_data.m_count = 0;
return true;
}
};
} // namespace detail
} // namespace __gnu_pbds
|
