3 // Copyright (C) 2005, 2006 Free Software Foundation, Inc.
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 2, or (at your option) any later
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.
16 // You should have received a copy of the GNU General Public License
17 // along with this library; see the file COPYING. If not, write to
18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
19 // MA 02111-1307, USA.
21 // As a special exception, you may use this file as part of a free
22 // software library without restriction. Specifically, if other files
23 // instantiate templates or use macros or inline functions from this
24 // file, or you compile this file and link it with other files to
25 // produce an executable, this file does not by itself cause the
26 // resulting executable to be covered by the GNU General Public
27 // License. This exception does not however invalidate any other
28 // reasons why the executable file might be covered by the GNU General
31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
33 // Permission to use, copy, modify, sell, and distribute this software
34 // is hereby granted without fee, provided that the above copyright
35 // notice appears in all copies, and that both that copyright notice
36 // and this permission notice appear in supporting documentation. None
37 // of the above authors, nor IBM Haifa Research Laboratories, make any
38 // representation about the suitability of this software for any
39 // purpose. It is provided "as is" without express or implied
43 * @file resize_policy.hpp
44 * Contains an implementation class for a binary_heap.
47 #ifndef PB_DS_BINARY_HEAP_RESIZE_POLICY_HPP
48 #define PB_DS_BINARY_HEAP_RESIZE_POLICY_HPP
50 #include <debug/debug.h>
57 #define PB_DS_CLASS_T_DEC template<typename Size_Type>
59 #define PB_DS_CLASS_C_DEC resize_policy<Size_Type>
61 template<typename Size_Type
>
65 typedef Size_Type size_type
;
77 swap(PB_DS_CLASS_C_DEC
& other
);
80 resize_needed_for_grow(size_type size
) const;
83 resize_needed_for_shrink(size_type size
) const;
86 grow_needed(size_type size
) const;
89 shrink_needed(size_type size
) const;
92 get_new_size_for_grow() const;
95 get_new_size_for_shrink() const;
98 get_new_size_for_arbitrary(size_type size
) const;
101 notify_grow_resize();
104 notify_shrink_resize();
107 notify_arbitrary(size_type actual_size
);
109 #ifdef _GLIBCXX_DEBUG
111 assert_valid() const;
114 #ifdef PB_DS_BINARY_HEAP_TRACE_
127 size_type m_next_shrink_size
;
128 size_type m_next_grow_size
;
135 m_next_shrink_size(0),
136 m_next_grow_size(min_size
)
137 { _GLIBCXX_DEBUG_ONLY(assert_valid();) }
142 swap(PB_DS_CLASS_C_DEC
& other
)
144 std::swap(m_next_shrink_size
, other
.m_next_shrink_size
);
145 std::swap(m_next_grow_size
, other
.m_next_grow_size
);
151 resize_needed_for_grow(size_type size
) const
153 _GLIBCXX_DEBUG_ASSERT(size
<= m_next_grow_size
);
154 return size
== m_next_grow_size
;
160 resize_needed_for_shrink(size_type size
) const
162 _GLIBCXX_DEBUG_ASSERT(size
<= m_next_grow_size
);
163 return size
== m_next_shrink_size
;
167 inline typename
PB_DS_CLASS_C_DEC::size_type
169 get_new_size_for_grow() const
170 { return m_next_grow_size
* factor
; }
173 inline typename
PB_DS_CLASS_C_DEC::size_type
175 get_new_size_for_shrink() const
177 const size_type half_size
= m_next_grow_size
/ factor
;
178 return std::max(static_cast<size_type
>(min_size
), half_size
);
182 inline typename
PB_DS_CLASS_C_DEC::size_type
184 get_new_size_for_arbitrary(size_type size
) const
186 size_type ret
= min_size
;
197 _GLIBCXX_DEBUG_ONLY(assert_valid();)
198 _GLIBCXX_DEBUG_ASSERT(m_next_grow_size
>= min_size
);
199 m_next_grow_size
*= factor
;
200 m_next_shrink_size
= m_next_grow_size
/ ratio
;
201 _GLIBCXX_DEBUG_ONLY(assert_valid();)
207 notify_shrink_resize()
209 _GLIBCXX_DEBUG_ONLY(assert_valid();)
210 m_next_shrink_size
/= factor
;
211 if (m_next_shrink_size
== 1)
212 m_next_shrink_size
= 0;
215 std::max(m_next_grow_size
/ factor
, static_cast<size_type
>(min_size
));
216 _GLIBCXX_DEBUG_ONLY(assert_valid();)
222 notify_arbitrary(size_type actual_size
)
224 m_next_grow_size
= actual_size
;
225 m_next_shrink_size
= m_next_grow_size
/ ratio
;
226 _GLIBCXX_DEBUG_ONLY(assert_valid();)
229 #ifdef _GLIBCXX_DEBUG
235 _GLIBCXX_DEBUG_ASSERT(m_next_shrink_size
== 0 ||
236 m_next_shrink_size
* ratio
== m_next_grow_size
);
238 _GLIBCXX_DEBUG_ASSERT(m_next_grow_size
>= min_size
);
242 #ifdef PB_DS_BINARY_HEAP_TRACE_
248 std::cerr
<< "shrink = " << m_next_shrink_size
<<
249 " grow = " << m_next_grow_size
<< std::endl
;
253 #undef PB_DS_CLASS_T_DEC
254 #undef PB_DS_CLASS_C_DEC
256 } // namespace detail
257 } // namespace __gnu_pbds