forked from KolibriOS/kolibrios
1064 lines
28 KiB
C
1064 lines
28 KiB
C
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// -*- C++ -*-
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// Copyright (C) 2007-2013 Free Software Foundation, Inc.
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//
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// This file is part of the GNU ISO C++ Library. This library is free
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// software; you can redistribute it and/or modify it under the terms
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// of the GNU General Public License as published by the Free Software
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// Foundation; either version 3, or (at your option) any later
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// version.
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// This library is distributed in the hope that it will be useful, but
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// WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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// Under Section 7 of GPL version 3, you are granted additional
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// permissions described in the GCC Runtime Library Exception, version
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// 3.1, as published by the Free Software Foundation.
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// You should have received a copy of the GNU General Public License and
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// a copy of the GCC Runtime Library Exception along with this program;
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
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// <http://www.gnu.org/licenses/>.
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/** @file parallel/losertree.h
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* @brief Many generic loser tree variants.
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* This file is a GNU parallel extension to the Standard C++ Library.
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*/
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// Written by Johannes Singler.
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#ifndef _GLIBCXX_PARALLEL_LOSERTREE_H
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#define _GLIBCXX_PARALLEL_LOSERTREE_H 1
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#include <bits/stl_algobase.h>
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#include <bits/stl_function.h>
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#include <parallel/features.h>
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#include <parallel/base.h>
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namespace __gnu_parallel
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{
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/**
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* @brief Guarded loser/tournament tree.
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*
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* The smallest element is at the top.
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*
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* Guarding is done explicitly through one flag _M_sup per element,
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* inf is not needed due to a better initialization routine. This
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* is a well-performing variant.
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*
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* @param _Tp the element type
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* @param _Compare the comparator to use, defaults to std::less<_Tp>
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*/
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template<typename _Tp, typename _Compare>
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class _LoserTreeBase
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{
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protected:
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/** @brief Internal representation of a _LoserTree element. */
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struct _Loser
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{
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/** @brief flag, true iff this is a "maximum" __sentinel. */
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bool _M_sup;
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/** @brief __index of the __source __sequence. */
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int _M_source;
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/** @brief _M_key of the element in the _LoserTree. */
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_Tp _M_key;
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};
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unsigned int _M_ik, _M_k, _M_offset;
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/** log_2{_M_k} */
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unsigned int _M_log_k;
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/** @brief _LoserTree __elements. */
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_Loser* _M_losers;
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/** @brief _Compare to use. */
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_Compare _M_comp;
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/**
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* @brief State flag that determines whether the _LoserTree is empty.
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*
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* Only used for building the _LoserTree.
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*/
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bool _M_first_insert;
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public:
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/**
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* @brief The constructor.
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*
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* @param __k The number of sequences to merge.
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* @param __comp The comparator to use.
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*/
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_LoserTreeBase(unsigned int __k, _Compare __comp)
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: _M_comp(__comp)
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{
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_M_ik = __k;
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// Compute log_2{_M_k} for the _Loser Tree
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_M_log_k = __rd_log2(_M_ik - 1) + 1;
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// Next greater power of 2.
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_M_k = 1 << _M_log_k;
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_M_offset = _M_k;
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// Avoid default-constructing _M_losers[]._M_key
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_M_losers = static_cast<_Loser*>(::operator new(2 * _M_k
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* sizeof(_Loser)));
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for (unsigned int __i = _M_ik - 1; __i < _M_k; ++__i)
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_M_losers[__i + _M_k]._M_sup = true;
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_M_first_insert = true;
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}
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/**
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* @brief The destructor.
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*/
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~_LoserTreeBase()
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{
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for (unsigned int __i = 0; __i < (2 * _M_k); ++__i)
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_M_losers[__i].~_Loser();
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::operator delete(_M_losers);
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}
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/**
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* @brief Initializes the sequence "_M_source" with the element "__key".
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*
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* @param __key the element to insert
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* @param __source __index of the __source __sequence
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* @param __sup flag that determines whether the value to insert is an
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* explicit __supremum.
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*/
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void
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__insert_start(const _Tp& __key, int __source, bool __sup)
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{
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unsigned int __pos = _M_k + __source;
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if (_M_first_insert)
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{
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// Construct all keys, so we can easily destruct them.
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for (unsigned int __i = 0; __i < (2 * _M_k); ++__i)
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::new(&(_M_losers[__i]._M_key)) _Tp(__key);
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_M_first_insert = false;
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}
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else
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_M_losers[__pos]._M_key = __key;
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_M_losers[__pos]._M_sup = __sup;
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_M_losers[__pos]._M_source = __source;
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}
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/**
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* @return the index of the sequence with the smallest element.
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*/
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int __get_min_source()
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{ return _M_losers[0]._M_source; }
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};
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/**
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* @brief Stable _LoserTree variant.
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*
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* Provides the stable implementations of insert_start, __init_winner,
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* __init and __delete_min_insert.
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*
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* Unstable variant is done using partial specialisation below.
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*/
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template<bool __stable/* default == true */, typename _Tp,
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typename _Compare>
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class _LoserTree
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: public _LoserTreeBase<_Tp, _Compare>
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{
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typedef _LoserTreeBase<_Tp, _Compare> _Base;
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using _Base::_M_k;
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using _Base::_M_comp;
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using _Base::_M_losers;
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using _Base::_M_first_insert;
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public:
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_LoserTree(unsigned int __k, _Compare __comp)
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: _Base::_LoserTreeBase(__k, __comp)
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{ }
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unsigned int
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__init_winner(unsigned int __root)
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{
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if (__root >= _M_k)
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return __root;
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else
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{
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unsigned int __left = __init_winner(2 * __root);
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unsigned int __right = __init_winner(2 * __root + 1);
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if (_M_losers[__right]._M_sup
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|| (!_M_losers[__left]._M_sup
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&& !_M_comp(_M_losers[__right]._M_key,
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_M_losers[__left]._M_key)))
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{
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// Left one is less or equal.
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_M_losers[__root] = _M_losers[__right];
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return __left;
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}
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else
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{
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// Right one is less.
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_M_losers[__root] = _M_losers[__left];
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return __right;
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}
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}
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}
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void __init()
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{ _M_losers[0] = _M_losers[__init_winner(1)]; }
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/**
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* @brief Delete the smallest element and insert a new element from
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* the previously smallest element's sequence.
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*
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* This implementation is stable.
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*/
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// Do not pass a const reference since __key will be used as
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// local variable.
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void
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__delete_min_insert(_Tp __key, bool __sup)
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{
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using std::swap;
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#if _GLIBCXX_ASSERTIONS
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// no dummy sequence can ever be at the top!
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_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
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#endif
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int __source = _M_losers[0]._M_source;
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for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
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__pos /= 2)
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{
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// The smaller one gets promoted, ties are broken by _M_source.
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if ((__sup && (!_M_losers[__pos]._M_sup
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|| _M_losers[__pos]._M_source < __source))
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|| (!__sup && !_M_losers[__pos]._M_sup
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&& ((_M_comp(_M_losers[__pos]._M_key, __key))
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|| (!_M_comp(__key, _M_losers[__pos]._M_key)
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&& _M_losers[__pos]._M_source < __source))))
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{
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// The other one is smaller.
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std::swap(_M_losers[__pos]._M_sup, __sup);
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std::swap(_M_losers[__pos]._M_source, __source);
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swap(_M_losers[__pos]._M_key, __key);
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}
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}
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_M_losers[0]._M_sup = __sup;
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_M_losers[0]._M_source = __source;
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_M_losers[0]._M_key = __key;
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}
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};
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/**
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* @brief Unstable _LoserTree variant.
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*
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* Stability (non-stable here) is selected with partial specialization.
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*/
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template<typename _Tp, typename _Compare>
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class _LoserTree</* __stable == */false, _Tp, _Compare>
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: public _LoserTreeBase<_Tp, _Compare>
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{
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typedef _LoserTreeBase<_Tp, _Compare> _Base;
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using _Base::_M_log_k;
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using _Base::_M_k;
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using _Base::_M_comp;
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using _Base::_M_losers;
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using _Base::_M_first_insert;
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public:
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_LoserTree(unsigned int __k, _Compare __comp)
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: _Base::_LoserTreeBase(__k, __comp)
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{ }
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/**
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* Computes the winner of the competition at position "__root".
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*
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* Called recursively (starting at 0) to build the initial tree.
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*
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* @param __root __index of the "game" to start.
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*/
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unsigned int
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__init_winner(unsigned int __root)
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{
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if (__root >= _M_k)
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return __root;
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else
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{
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unsigned int __left = __init_winner(2 * __root);
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unsigned int __right = __init_winner(2 * __root + 1);
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if (_M_losers[__right]._M_sup
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|| (!_M_losers[__left]._M_sup
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&& !_M_comp(_M_losers[__right]._M_key,
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_M_losers[__left]._M_key)))
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{
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// Left one is less or equal.
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_M_losers[__root] = _M_losers[__right];
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return __left;
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}
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else
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{
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// Right one is less.
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_M_losers[__root] = _M_losers[__left];
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return __right;
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}
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}
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}
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void
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__init()
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{ _M_losers[0] = _M_losers[__init_winner(1)]; }
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/**
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* Delete the _M_key smallest element and insert the element __key
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* instead.
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*
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* @param __key the _M_key to insert
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* @param __sup true iff __key is an explicitly marked supremum
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*/
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// Do not pass a const reference since __key will be used as local
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// variable.
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void
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__delete_min_insert(_Tp __key, bool __sup)
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{
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using std::swap;
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#if _GLIBCXX_ASSERTIONS
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// no dummy sequence can ever be at the top!
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_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
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#endif
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int __source = _M_losers[0]._M_source;
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for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
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__pos /= 2)
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{
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// The smaller one gets promoted.
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if (__sup || (!_M_losers[__pos]._M_sup
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&& _M_comp(_M_losers[__pos]._M_key, __key)))
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{
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// The other one is smaller.
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std::swap(_M_losers[__pos]._M_sup, __sup);
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std::swap(_M_losers[__pos]._M_source, __source);
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swap(_M_losers[__pos]._M_key, __key);
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}
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}
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_M_losers[0]._M_sup = __sup;
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_M_losers[0]._M_source = __source;
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_M_losers[0]._M_key = __key;
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}
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};
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/**
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* @brief Base class of _Loser Tree implementation using pointers.
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*/
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template<typename _Tp, typename _Compare>
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class _LoserTreePointerBase
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{
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protected:
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||
|
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/** @brief Internal representation of _LoserTree __elements. */
|
||
|
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struct _Loser
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||
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{
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bool _M_sup;
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int _M_source;
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const _Tp* _M_keyp;
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};
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unsigned int _M_ik, _M_k, _M_offset;
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_Loser* _M_losers;
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||
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_Compare _M_comp;
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||
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public:
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_LoserTreePointerBase(unsigned int __k,
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_Compare __comp = std::less<_Tp>())
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|
|
: _M_comp(__comp)
|
||
|
|
{
|
||
|
|
_M_ik = __k;
|
||
|
|
|
||
|
|
// Next greater power of 2.
|
||
|
|
_M_k = 1 << (__rd_log2(_M_ik - 1) + 1);
|
||
|
|
_M_offset = _M_k;
|
||
|
|
_M_losers = new _Loser[_M_k * 2];
|
||
|
|
for (unsigned int __i = _M_ik - 1; __i < _M_k; __i++)
|
||
|
|
_M_losers[__i + _M_k]._M_sup = true;
|
||
|
|
}
|
||
|
|
|
||
|
|
~_LoserTreePointerBase()
|
||
|
|
{ delete[] _M_losers; }
|
||
|
|
|
||
|
|
int __get_min_source()
|
||
|
|
{ return _M_losers[0]._M_source; }
|
||
|
|
|
||
|
|
void __insert_start(const _Tp& __key, int __source, bool __sup)
|
||
|
|
{
|
||
|
|
unsigned int __pos = _M_k + __source;
|
||
|
|
|
||
|
|
_M_losers[__pos]._M_sup = __sup;
|
||
|
|
_M_losers[__pos]._M_source = __source;
|
||
|
|
_M_losers[__pos]._M_keyp = &__key;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Stable _LoserTree implementation.
|
||
|
|
*
|
||
|
|
* The unstable variant is implemented using partial instantiation below.
|
||
|
|
*/
|
||
|
|
template<bool __stable/* default == true */, typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreePointer
|
||
|
|
: public _LoserTreePointerBase<_Tp, _Compare>
|
||
|
|
{
|
||
|
|
typedef _LoserTreePointerBase<_Tp, _Compare> _Base;
|
||
|
|
using _Base::_M_k;
|
||
|
|
using _Base::_M_comp;
|
||
|
|
using _Base::_M_losers;
|
||
|
|
|
||
|
|
public:
|
||
|
|
_LoserTreePointer(unsigned int __k, _Compare __comp = std::less<_Tp>())
|
||
|
|
: _Base::_LoserTreePointerBase(__k, __comp)
|
||
|
|
{ }
|
||
|
|
|
||
|
|
unsigned int
|
||
|
|
__init_winner(unsigned int __root)
|
||
|
|
{
|
||
|
|
if (__root >= _M_k)
|
||
|
|
return __root;
|
||
|
|
else
|
||
|
|
{
|
||
|
|
unsigned int __left = __init_winner(2 * __root);
|
||
|
|
unsigned int __right = __init_winner(2 * __root + 1);
|
||
|
|
if (_M_losers[__right]._M_sup
|
||
|
|
|| (!_M_losers[__left]._M_sup
|
||
|
|
&& !_M_comp(*_M_losers[__right]._M_keyp,
|
||
|
|
*_M_losers[__left]._M_keyp)))
|
||
|
|
{
|
||
|
|
// Left one is less or equal.
|
||
|
|
_M_losers[__root] = _M_losers[__right];
|
||
|
|
return __left;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Right one is less.
|
||
|
|
_M_losers[__root] = _M_losers[__left];
|
||
|
|
return __right;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void __init()
|
||
|
|
{ _M_losers[0] = _M_losers[__init_winner(1)]; }
|
||
|
|
|
||
|
|
void __delete_min_insert(const _Tp& __key, bool __sup)
|
||
|
|
{
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
const _Tp* __keyp = &__key;
|
||
|
|
int __source = _M_losers[0]._M_source;
|
||
|
|
for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
|
||
|
|
__pos /= 2)
|
||
|
|
{
|
||
|
|
// The smaller one gets promoted, ties are broken by __source.
|
||
|
|
if ((__sup && (!_M_losers[__pos]._M_sup
|
||
|
|
|| _M_losers[__pos]._M_source < __source))
|
||
|
|
|| (!__sup && !_M_losers[__pos]._M_sup &&
|
||
|
|
((_M_comp(*_M_losers[__pos]._M_keyp, *__keyp))
|
||
|
|
|| (!_M_comp(*__keyp, *_M_losers[__pos]._M_keyp)
|
||
|
|
&& _M_losers[__pos]._M_source < __source))))
|
||
|
|
{
|
||
|
|
// The other one is smaller.
|
||
|
|
std::swap(_M_losers[__pos]._M_sup, __sup);
|
||
|
|
std::swap(_M_losers[__pos]._M_source, __source);
|
||
|
|
std::swap(_M_losers[__pos]._M_keyp, __keyp);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
_M_losers[0]._M_sup = __sup;
|
||
|
|
_M_losers[0]._M_source = __source;
|
||
|
|
_M_losers[0]._M_keyp = __keyp;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Unstable _LoserTree implementation.
|
||
|
|
*
|
||
|
|
* The stable variant is above.
|
||
|
|
*/
|
||
|
|
template<typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreePointer</* __stable == */false, _Tp, _Compare>
|
||
|
|
: public _LoserTreePointerBase<_Tp, _Compare>
|
||
|
|
{
|
||
|
|
typedef _LoserTreePointerBase<_Tp, _Compare> _Base;
|
||
|
|
using _Base::_M_k;
|
||
|
|
using _Base::_M_comp;
|
||
|
|
using _Base::_M_losers;
|
||
|
|
|
||
|
|
public:
|
||
|
|
_LoserTreePointer(unsigned int __k, _Compare __comp = std::less<_Tp>())
|
||
|
|
: _Base::_LoserTreePointerBase(__k, __comp)
|
||
|
|
{ }
|
||
|
|
|
||
|
|
unsigned int
|
||
|
|
__init_winner(unsigned int __root)
|
||
|
|
{
|
||
|
|
if (__root >= _M_k)
|
||
|
|
return __root;
|
||
|
|
else
|
||
|
|
{
|
||
|
|
unsigned int __left = __init_winner(2 * __root);
|
||
|
|
unsigned int __right = __init_winner(2 * __root + 1);
|
||
|
|
if (_M_losers[__right]._M_sup
|
||
|
|
|| (!_M_losers[__left]._M_sup
|
||
|
|
&& !_M_comp(*_M_losers[__right]._M_keyp,
|
||
|
|
*_M_losers[__left]._M_keyp)))
|
||
|
|
{
|
||
|
|
// Left one is less or equal.
|
||
|
|
_M_losers[__root] = _M_losers[__right];
|
||
|
|
return __left;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Right one is less.
|
||
|
|
_M_losers[__root] = _M_losers[__left];
|
||
|
|
return __right;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void __init()
|
||
|
|
{ _M_losers[0] = _M_losers[__init_winner(1)]; }
|
||
|
|
|
||
|
|
void __delete_min_insert(const _Tp& __key, bool __sup)
|
||
|
|
{
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
const _Tp* __keyp = &__key;
|
||
|
|
int __source = _M_losers[0]._M_source;
|
||
|
|
for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
|
||
|
|
__pos /= 2)
|
||
|
|
{
|
||
|
|
// The smaller one gets promoted.
|
||
|
|
if (__sup || (!_M_losers[__pos]._M_sup
|
||
|
|
&& _M_comp(*_M_losers[__pos]._M_keyp, *__keyp)))
|
||
|
|
{
|
||
|
|
// The other one is smaller.
|
||
|
|
std::swap(_M_losers[__pos]._M_sup, __sup);
|
||
|
|
std::swap(_M_losers[__pos]._M_source, __source);
|
||
|
|
std::swap(_M_losers[__pos]._M_keyp, __keyp);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
_M_losers[0]._M_sup = __sup;
|
||
|
|
_M_losers[0]._M_source = __source;
|
||
|
|
_M_losers[0]._M_keyp = __keyp;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/** @brief Base class for unguarded _LoserTree implementation.
|
||
|
|
*
|
||
|
|
* The whole element is copied into the tree structure.
|
||
|
|
*
|
||
|
|
* No guarding is done, therefore not a single input sequence must
|
||
|
|
* run empty. Unused __sequence heads are marked with a sentinel which
|
||
|
|
* is > all elements that are to be merged.
|
||
|
|
*
|
||
|
|
* This is a very fast variant.
|
||
|
|
*/
|
||
|
|
template<typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreeUnguardedBase
|
||
|
|
{
|
||
|
|
protected:
|
||
|
|
struct _Loser
|
||
|
|
{
|
||
|
|
int _M_source;
|
||
|
|
_Tp _M_key;
|
||
|
|
};
|
||
|
|
|
||
|
|
unsigned int _M_ik, _M_k, _M_offset;
|
||
|
|
_Loser* _M_losers;
|
||
|
|
_Compare _M_comp;
|
||
|
|
|
||
|
|
public:
|
||
|
|
_LoserTreeUnguardedBase(unsigned int __k, const _Tp& __sentinel,
|
||
|
|
_Compare __comp = std::less<_Tp>())
|
||
|
|
: _M_comp(__comp)
|
||
|
|
{
|
||
|
|
_M_ik = __k;
|
||
|
|
|
||
|
|
// Next greater power of 2.
|
||
|
|
_M_k = 1 << (__rd_log2(_M_ik - 1) + 1);
|
||
|
|
_M_offset = _M_k;
|
||
|
|
// Avoid default-constructing _M_losers[]._M_key
|
||
|
|
_M_losers = static_cast<_Loser*>(::operator new(2 * _M_k
|
||
|
|
* sizeof(_Loser)));
|
||
|
|
|
||
|
|
for (unsigned int __i = 0; __i < _M_k; ++__i)
|
||
|
|
{
|
||
|
|
::new(&(_M_losers[__i]._M_key)) _Tp(__sentinel);
|
||
|
|
_M_losers[__i]._M_source = -1;
|
||
|
|
}
|
||
|
|
for (unsigned int __i = _M_k + _M_ik - 1; __i < (2 * _M_k); ++__i)
|
||
|
|
{
|
||
|
|
::new(&(_M_losers[__i]._M_key)) _Tp(__sentinel);
|
||
|
|
_M_losers[__i]._M_source = -1;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
~_LoserTreeUnguardedBase()
|
||
|
|
{
|
||
|
|
for (unsigned int __i = 0; __i < (2 * _M_k); ++__i)
|
||
|
|
_M_losers[__i].~_Loser();
|
||
|
|
::operator delete(_M_losers);
|
||
|
|
}
|
||
|
|
|
||
|
|
int
|
||
|
|
__get_min_source()
|
||
|
|
{
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
return _M_losers[0]._M_source;
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__insert_start(const _Tp& __key, int __source, bool)
|
||
|
|
{
|
||
|
|
unsigned int __pos = _M_k + __source;
|
||
|
|
|
||
|
|
::new(&(_M_losers[__pos]._M_key)) _Tp(__key);
|
||
|
|
_M_losers[__pos]._M_source = __source;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Stable implementation of unguarded _LoserTree.
|
||
|
|
*
|
||
|
|
* Unstable variant is selected below with partial specialization.
|
||
|
|
*/
|
||
|
|
template<bool __stable/* default == true */, typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreeUnguarded
|
||
|
|
: public _LoserTreeUnguardedBase<_Tp, _Compare>
|
||
|
|
{
|
||
|
|
typedef _LoserTreeUnguardedBase<_Tp, _Compare> _Base;
|
||
|
|
using _Base::_M_k;
|
||
|
|
using _Base::_M_comp;
|
||
|
|
using _Base::_M_losers;
|
||
|
|
|
||
|
|
public:
|
||
|
|
_LoserTreeUnguarded(unsigned int __k, const _Tp& __sentinel,
|
||
|
|
_Compare __comp = std::less<_Tp>())
|
||
|
|
: _Base::_LoserTreeUnguardedBase(__k, __sentinel, __comp)
|
||
|
|
{ }
|
||
|
|
|
||
|
|
unsigned int
|
||
|
|
__init_winner(unsigned int __root)
|
||
|
|
{
|
||
|
|
if (__root >= _M_k)
|
||
|
|
return __root;
|
||
|
|
else
|
||
|
|
{
|
||
|
|
unsigned int __left = __init_winner(2 * __root);
|
||
|
|
unsigned int __right = __init_winner(2 * __root + 1);
|
||
|
|
if (!_M_comp(_M_losers[__right]._M_key,
|
||
|
|
_M_losers[__left]._M_key))
|
||
|
|
{
|
||
|
|
// Left one is less or equal.
|
||
|
|
_M_losers[__root] = _M_losers[__right];
|
||
|
|
return __left;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Right one is less.
|
||
|
|
_M_losers[__root] = _M_losers[__left];
|
||
|
|
return __right;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__init()
|
||
|
|
{
|
||
|
|
_M_losers[0] = _M_losers[__init_winner(1)];
|
||
|
|
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top at the beginning
|
||
|
|
// (0 sequences!)
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
// Do not pass a const reference since __key will be used as
|
||
|
|
// local variable.
|
||
|
|
void
|
||
|
|
__delete_min_insert(_Tp __key, bool)
|
||
|
|
{
|
||
|
|
using std::swap;
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
int __source = _M_losers[0]._M_source;
|
||
|
|
for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
|
||
|
|
__pos /= 2)
|
||
|
|
{
|
||
|
|
// The smaller one gets promoted, ties are broken by _M_source.
|
||
|
|
if (_M_comp(_M_losers[__pos]._M_key, __key)
|
||
|
|
|| (!_M_comp(__key, _M_losers[__pos]._M_key)
|
||
|
|
&& _M_losers[__pos]._M_source < __source))
|
||
|
|
{
|
||
|
|
// The other one is smaller.
|
||
|
|
std::swap(_M_losers[__pos]._M_source, __source);
|
||
|
|
swap(_M_losers[__pos]._M_key, __key);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
_M_losers[0]._M_source = __source;
|
||
|
|
_M_losers[0]._M_key = __key;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Non-Stable implementation of unguarded _LoserTree.
|
||
|
|
*
|
||
|
|
* Stable implementation is above.
|
||
|
|
*/
|
||
|
|
template<typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreeUnguarded</* __stable == */false, _Tp, _Compare>
|
||
|
|
: public _LoserTreeUnguardedBase<_Tp, _Compare>
|
||
|
|
{
|
||
|
|
typedef _LoserTreeUnguardedBase<_Tp, _Compare> _Base;
|
||
|
|
using _Base::_M_k;
|
||
|
|
using _Base::_M_comp;
|
||
|
|
using _Base::_M_losers;
|
||
|
|
|
||
|
|
public:
|
||
|
|
_LoserTreeUnguarded(unsigned int __k, const _Tp& __sentinel,
|
||
|
|
_Compare __comp = std::less<_Tp>())
|
||
|
|
: _Base::_LoserTreeUnguardedBase(__k, __sentinel, __comp)
|
||
|
|
{ }
|
||
|
|
|
||
|
|
unsigned int
|
||
|
|
__init_winner(unsigned int __root)
|
||
|
|
{
|
||
|
|
if (__root >= _M_k)
|
||
|
|
return __root;
|
||
|
|
else
|
||
|
|
{
|
||
|
|
unsigned int __left = __init_winner(2 * __root);
|
||
|
|
unsigned int __right = __init_winner(2 * __root + 1);
|
||
|
|
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// If __left one is sentinel then __right one must be, too.
|
||
|
|
if (_M_losers[__left]._M_source == -1)
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[__right]._M_source == -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (!_M_comp(_M_losers[__right]._M_key,
|
||
|
|
_M_losers[__left]._M_key))
|
||
|
|
{
|
||
|
|
// Left one is less or equal.
|
||
|
|
_M_losers[__root] = _M_losers[__right];
|
||
|
|
return __left;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Right one is less.
|
||
|
|
_M_losers[__root] = _M_losers[__left];
|
||
|
|
return __right;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__init()
|
||
|
|
{
|
||
|
|
_M_losers[0] = _M_losers[__init_winner(1)];
|
||
|
|
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top at the beginning
|
||
|
|
// (0 sequences!)
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
// Do not pass a const reference since __key will be used as
|
||
|
|
// local variable.
|
||
|
|
void
|
||
|
|
__delete_min_insert(_Tp __key, bool)
|
||
|
|
{
|
||
|
|
using std::swap;
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
int __source = _M_losers[0]._M_source;
|
||
|
|
for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
|
||
|
|
__pos /= 2)
|
||
|
|
{
|
||
|
|
// The smaller one gets promoted.
|
||
|
|
if (_M_comp(_M_losers[__pos]._M_key, __key))
|
||
|
|
{
|
||
|
|
// The other one is smaller.
|
||
|
|
std::swap(_M_losers[__pos]._M_source, __source);
|
||
|
|
swap(_M_losers[__pos]._M_key, __key);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
_M_losers[0]._M_source = __source;
|
||
|
|
_M_losers[0]._M_key = __key;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/** @brief Unguarded loser tree, keeping only pointers to the
|
||
|
|
* elements in the tree structure.
|
||
|
|
*
|
||
|
|
* No guarding is done, therefore not a single input sequence must
|
||
|
|
* run empty. This is a very fast variant.
|
||
|
|
*/
|
||
|
|
template<typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreePointerUnguardedBase
|
||
|
|
{
|
||
|
|
protected:
|
||
|
|
struct _Loser
|
||
|
|
{
|
||
|
|
int _M_source;
|
||
|
|
const _Tp* _M_keyp;
|
||
|
|
};
|
||
|
|
|
||
|
|
unsigned int _M_ik, _M_k, _M_offset;
|
||
|
|
_Loser* _M_losers;
|
||
|
|
_Compare _M_comp;
|
||
|
|
|
||
|
|
public:
|
||
|
|
|
||
|
|
_LoserTreePointerUnguardedBase(unsigned int __k, const _Tp& __sentinel,
|
||
|
|
_Compare __comp = std::less<_Tp>())
|
||
|
|
: _M_comp(__comp)
|
||
|
|
{
|
||
|
|
_M_ik = __k;
|
||
|
|
|
||
|
|
// Next greater power of 2.
|
||
|
|
_M_k = 1 << (__rd_log2(_M_ik - 1) + 1);
|
||
|
|
_M_offset = _M_k;
|
||
|
|
// Avoid default-constructing _M_losers[]._M_key
|
||
|
|
_M_losers = new _Loser[2 * _M_k];
|
||
|
|
|
||
|
|
for (unsigned int __i = _M_k + _M_ik - 1; __i < (2 * _M_k); ++__i)
|
||
|
|
{
|
||
|
|
_M_losers[__i]._M_keyp = &__sentinel;
|
||
|
|
_M_losers[__i]._M_source = -1;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
~_LoserTreePointerUnguardedBase()
|
||
|
|
{ delete[] _M_losers; }
|
||
|
|
|
||
|
|
int
|
||
|
|
__get_min_source()
|
||
|
|
{
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
return _M_losers[0]._M_source;
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__insert_start(const _Tp& __key, int __source, bool)
|
||
|
|
{
|
||
|
|
unsigned int __pos = _M_k + __source;
|
||
|
|
|
||
|
|
_M_losers[__pos]._M_keyp = &__key;
|
||
|
|
_M_losers[__pos]._M_source = __source;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Stable unguarded _LoserTree variant storing pointers.
|
||
|
|
*
|
||
|
|
* Unstable variant is implemented below using partial specialization.
|
||
|
|
*/
|
||
|
|
template<bool __stable/* default == true */, typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreePointerUnguarded
|
||
|
|
: public _LoserTreePointerUnguardedBase<_Tp, _Compare>
|
||
|
|
{
|
||
|
|
typedef _LoserTreePointerUnguardedBase<_Tp, _Compare> _Base;
|
||
|
|
using _Base::_M_k;
|
||
|
|
using _Base::_M_comp;
|
||
|
|
using _Base::_M_losers;
|
||
|
|
|
||
|
|
public:
|
||
|
|
_LoserTreePointerUnguarded(unsigned int __k, const _Tp& __sentinel,
|
||
|
|
_Compare __comp = std::less<_Tp>())
|
||
|
|
: _Base::_LoserTreePointerUnguardedBase(__k, __sentinel, __comp)
|
||
|
|
{ }
|
||
|
|
|
||
|
|
unsigned int
|
||
|
|
__init_winner(unsigned int __root)
|
||
|
|
{
|
||
|
|
if (__root >= _M_k)
|
||
|
|
return __root;
|
||
|
|
else
|
||
|
|
{
|
||
|
|
unsigned int __left = __init_winner(2 * __root);
|
||
|
|
unsigned int __right = __init_winner(2 * __root + 1);
|
||
|
|
if (!_M_comp(*_M_losers[__right]._M_keyp,
|
||
|
|
*_M_losers[__left]._M_keyp))
|
||
|
|
{
|
||
|
|
// Left one is less or equal.
|
||
|
|
_M_losers[__root] = _M_losers[__right];
|
||
|
|
return __left;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Right one is less.
|
||
|
|
_M_losers[__root] = _M_losers[__left];
|
||
|
|
return __right;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__init()
|
||
|
|
{
|
||
|
|
_M_losers[0] = _M_losers[__init_winner(1)];
|
||
|
|
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top at the beginning
|
||
|
|
// (0 sequences!)
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__delete_min_insert(const _Tp& __key, bool __sup)
|
||
|
|
{
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
const _Tp* __keyp = &__key;
|
||
|
|
int __source = _M_losers[0]._M_source;
|
||
|
|
for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
|
||
|
|
__pos /= 2)
|
||
|
|
{
|
||
|
|
// The smaller one gets promoted, ties are broken by _M_source.
|
||
|
|
if (_M_comp(*_M_losers[__pos]._M_keyp, *__keyp)
|
||
|
|
|| (!_M_comp(*__keyp, *_M_losers[__pos]._M_keyp)
|
||
|
|
&& _M_losers[__pos]._M_source < __source))
|
||
|
|
{
|
||
|
|
// The other one is smaller.
|
||
|
|
std::swap(_M_losers[__pos]._M_source, __source);
|
||
|
|
std::swap(_M_losers[__pos]._M_keyp, __keyp);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
_M_losers[0]._M_source = __source;
|
||
|
|
_M_losers[0]._M_keyp = __keyp;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* @brief Unstable unguarded _LoserTree variant storing pointers.
|
||
|
|
*
|
||
|
|
* Stable variant is above.
|
||
|
|
*/
|
||
|
|
template<typename _Tp, typename _Compare>
|
||
|
|
class _LoserTreePointerUnguarded</* __stable == */false, _Tp, _Compare>
|
||
|
|
: public _LoserTreePointerUnguardedBase<_Tp, _Compare>
|
||
|
|
{
|
||
|
|
typedef _LoserTreePointerUnguardedBase<_Tp, _Compare> _Base;
|
||
|
|
using _Base::_M_k;
|
||
|
|
using _Base::_M_comp;
|
||
|
|
using _Base::_M_losers;
|
||
|
|
|
||
|
|
public:
|
||
|
|
_LoserTreePointerUnguarded(unsigned int __k, const _Tp& __sentinel,
|
||
|
|
_Compare __comp = std::less<_Tp>())
|
||
|
|
: _Base::_LoserTreePointerUnguardedBase(__k, __sentinel, __comp)
|
||
|
|
{ }
|
||
|
|
|
||
|
|
unsigned int
|
||
|
|
__init_winner(unsigned int __root)
|
||
|
|
{
|
||
|
|
if (__root >= _M_k)
|
||
|
|
return __root;
|
||
|
|
else
|
||
|
|
{
|
||
|
|
unsigned int __left = __init_winner(2 * __root);
|
||
|
|
unsigned int __right = __init_winner(2 * __root + 1);
|
||
|
|
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// If __left one is sentinel then __right one must be, too.
|
||
|
|
if (_M_losers[__left]._M_source == -1)
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[__right]._M_source == -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (!_M_comp(*_M_losers[__right]._M_keyp,
|
||
|
|
*_M_losers[__left]._M_keyp))
|
||
|
|
{
|
||
|
|
// Left one is less or equal.
|
||
|
|
_M_losers[__root] = _M_losers[__right];
|
||
|
|
return __left;
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
// Right one is less.
|
||
|
|
_M_losers[__root] = _M_losers[__left];
|
||
|
|
return __right;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__init()
|
||
|
|
{
|
||
|
|
_M_losers[0] = _M_losers[__init_winner(1)];
|
||
|
|
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top at the beginning
|
||
|
|
// (0 sequences!)
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
}
|
||
|
|
|
||
|
|
void
|
||
|
|
__delete_min_insert(const _Tp& __key, bool __sup)
|
||
|
|
{
|
||
|
|
#if _GLIBCXX_ASSERTIONS
|
||
|
|
// no dummy sequence can ever be at the top!
|
||
|
|
_GLIBCXX_PARALLEL_ASSERT(_M_losers[0]._M_source != -1);
|
||
|
|
#endif
|
||
|
|
|
||
|
|
const _Tp* __keyp = &__key;
|
||
|
|
int __source = _M_losers[0]._M_source;
|
||
|
|
for (unsigned int __pos = (_M_k + __source) / 2; __pos > 0;
|
||
|
|
__pos /= 2)
|
||
|
|
{
|
||
|
|
// The smaller one gets promoted.
|
||
|
|
if (_M_comp(*(_M_losers[__pos]._M_keyp), *__keyp))
|
||
|
|
{
|
||
|
|
// The other one is smaller.
|
||
|
|
std::swap(_M_losers[__pos]._M_source, __source);
|
||
|
|
std::swap(_M_losers[__pos]._M_keyp, __keyp);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
_M_losers[0]._M_source = __source;
|
||
|
|
_M_losers[0]._M_keyp = __keyp;
|
||
|
|
}
|
||
|
|
};
|
||
|
|
} // namespace __gnu_parallel
|
||
|
|
|
||
|
|
#endif /* _GLIBCXX_PARALLEL_LOSERTREE_H */
|