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// -*- C++ -*- |
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|
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// Copyright (C) 2007-2021 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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|
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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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|
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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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|
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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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|
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/** @file parallel/multiseq_selection.h |
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* @brief Functions to find elements of a certain global __rank in |
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* multiple sorted sequences. Also serves for splitting such |
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* sequence sets. |
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* |
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* The algorithm description can be found in |
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* |
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* P. J. Varman, S. D. Scheufler, B. R. Iyer, and G. R. Ricard. |
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* Merging Multiple Lists on Hierarchical-Memory Multiprocessors. |
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* Journal of Parallel and Distributed Computing, 12(2):171-177, 1991. |
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* |
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* This file is a GNU parallel extension to the Standard C++ Library. |
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*/ |
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|
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// Written by Johannes Singler. |
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|
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#ifndef _GLIBCXX_PARALLEL_MULTISEQ_SELECTION_H |
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#define _GLIBCXX_PARALLEL_MULTISEQ_SELECTION_H 1 |
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|
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#include <vector> |
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#include <queue> |
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|
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#include <bits/stl_algo.h> |
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|
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namespace __gnu_parallel |
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{ |
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/** @brief Compare __a pair of types lexicographically, ascending. */ |
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template<typename _T1, typename _T2, typename _Compare> |
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class _Lexicographic |
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: public std::binary_function<std::pair<_T1, _T2>, |
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std::pair<_T1, _T2>, bool> |
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{ |
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private: |
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_Compare& _M_comp; |
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|
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public: |
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_Lexicographic(_Compare& __comp) : _M_comp(__comp) { } |
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|
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bool |
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operator()(const std::pair<_T1, _T2>& __p1, |
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const std::pair<_T1, _T2>& __p2) const |
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{ |
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if (_M_comp(__p1.first, __p2.first)) |
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return true; |
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|
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if (_M_comp(__p2.first, __p1.first)) |
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return false; |
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|
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// Firsts are equal. |
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return __p1.second < __p2.second; |
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} |
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}; |
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|
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/** @brief Compare __a pair of types lexicographically, descending. */ |
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template<typename _T1, typename _T2, typename _Compare> |
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class _LexicographicReverse : public std::binary_function<_T1, _T2, bool> |
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{ |
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private: |
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_Compare& _M_comp; |
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|
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public: |
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_LexicographicReverse(_Compare& __comp) : _M_comp(__comp) { } |
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|
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bool |
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operator()(const std::pair<_T1, _T2>& __p1, |
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const std::pair<_T1, _T2>& __p2) const |
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{ |
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if (_M_comp(__p2.first, __p1.first)) |
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return true; |
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|
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if (_M_comp(__p1.first, __p2.first)) |
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return false; |
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|
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// Firsts are equal. |
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return __p2.second < __p1.second; |
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} |
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}; |
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|
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/** |
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* @brief Splits several sorted sequences at a certain global __rank, |
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* resulting in a splitting point for each sequence. |
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* The sequences are passed via a sequence of random-access |
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* iterator pairs, none of the sequences may be empty. If there |
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* are several equal elements across the split, the ones on the |
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* __left side will be chosen from sequences with smaller number. |
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* @param __begin_seqs Begin of the sequence of iterator pairs. |
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* @param __end_seqs End of the sequence of iterator pairs. |
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* @param __rank The global rank to partition at. |
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* @param __begin_offsets A random-access __sequence __begin where the |
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* __result will be stored in. Each element of the sequence is an |
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* iterator that points to the first element on the greater part of |
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* the respective __sequence. |
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* @param __comp The ordering functor, defaults to std::less<_Tp>. |
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*/ |
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template<typename _RanSeqs, typename _RankType, typename _RankIterator, |
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typename _Compare> |
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void |
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multiseq_partition(_RanSeqs __begin_seqs, _RanSeqs __end_seqs, |
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_RankType __rank, |
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_RankIterator __begin_offsets, |
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_Compare __comp = std::less< |
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typename std::iterator_traits<typename |
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std::iterator_traits<_RanSeqs>::value_type:: |
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first_type>::value_type>()) // std::less<_Tp> |
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{ |
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_GLIBCXX_CALL(__end_seqs - __begin_seqs) |
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|
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typedef typename std::iterator_traits<_RanSeqs>::value_type::first_type |
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_It; |
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typedef typename std::iterator_traits<_RanSeqs>::difference_type |
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_SeqNumber; |
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typedef typename std::iterator_traits<_It>::difference_type |
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_DifferenceType; |
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typedef typename std::iterator_traits<_It>::value_type _ValueType; |
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|
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_Lexicographic<_ValueType, _SeqNumber, _Compare> __lcomp(__comp); |
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_LexicographicReverse<_ValueType, _SeqNumber, _Compare> __lrcomp(__comp); |
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|
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// Number of sequences, number of elements in total (possibly |
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// including padding). |
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_DifferenceType __m = std::distance(__begin_seqs, __end_seqs), __nn = 0, |
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__nmax, __n, __r; |
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|
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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{ |
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__nn += std::distance(__begin_seqs[__i].first, |
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__begin_seqs[__i].second); |
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_GLIBCXX_PARALLEL_ASSERT( |
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std::distance(__begin_seqs[__i].first, |
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__begin_seqs[__i].second) > 0); |
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} |
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|
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if (__rank == __nn) |
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{ |
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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__begin_offsets[__i] = __begin_seqs[__i].second; // Very end. |
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// Return __m - 1; |
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return; |
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} |
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|
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_GLIBCXX_PARALLEL_ASSERT(__m != 0); |
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_GLIBCXX_PARALLEL_ASSERT(__nn != 0); |
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_GLIBCXX_PARALLEL_ASSERT(__rank >= 0); |
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_GLIBCXX_PARALLEL_ASSERT(__rank < __nn); |
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|
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_DifferenceType* __ns = new _DifferenceType[__m]; |
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_DifferenceType* __a = new _DifferenceType[__m]; |
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_DifferenceType* __b = new _DifferenceType[__m]; |
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_DifferenceType __l; |
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|
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__ns[0] = std::distance(__begin_seqs[0].first, __begin_seqs[0].second); |
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__nmax = __ns[0]; |
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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{ |
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__ns[__i] = std::distance(__begin_seqs[__i].first, |
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__begin_seqs[__i].second); |
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__nmax = std::max(__nmax, __ns[__i]); |
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} |
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|
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__r = __rd_log2(__nmax) + 1; |
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|
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// Pad all lists to this length, at least as long as any ns[__i], |
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// equality iff __nmax = 2^__k - 1. |
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__l = (1ULL << __r) - 1; |
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|
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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{ |
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__a[__i] = 0; |
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__b[__i] = __l; |
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} |
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__n = __l / 2; |
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|
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// Invariants: |
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// 0 <= __a[__i] <= __ns[__i], 0 <= __b[__i] <= __l |
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|
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#define __S(__i) (__begin_seqs[__i].first) |
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|
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// Initial partition. |
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std::vector<std::pair<_ValueType, _SeqNumber> > __sample; |
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|
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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if (__n < __ns[__i]) //__sequence long enough |
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__sample.push_back(std::make_pair(__S(__i)[__n], __i)); |
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__gnu_sequential::sort(__sample.begin(), __sample.end(), __lcomp); |
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|
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for (_SeqNumber __i = 0; __i < __m; __i++) //conceptual infinity |
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if (__n >= __ns[__i]) //__sequence too short, conceptual infinity |
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__sample.push_back( |
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std::make_pair(__S(__i)[0] /*__dummy element*/, __i)); |
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|
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_DifferenceType __localrank = __rank / __l; |
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|
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_SeqNumber __j; |
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for (__j = 0; |
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__j < __localrank && ((__n + 1) <= __ns[__sample[__j].second]); |
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++__j) |
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__a[__sample[__j].second] += __n + 1; |
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for (; __j < __m; __j++) |
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__b[__sample[__j].second] -= __n + 1; |
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|
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// Further refinement. |
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while (__n > 0) |
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{ |
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__n /= 2; |
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|
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_SeqNumber __lmax_seq = -1; // to avoid warning |
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const _ValueType* __lmax = 0; // impossible to avoid the warning? |
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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{ |
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if (__a[__i] > 0) |
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{ |
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if (!__lmax) |
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{ |
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__lmax = &(__S(__i)[__a[__i] - 1]); |
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__lmax_seq = __i; |
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} |
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else |
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{ |
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// Max, favor rear sequences. |
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if (!__comp(__S(__i)[__a[__i] - 1], *__lmax)) |
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{ |
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__lmax = &(__S(__i)[__a[__i] - 1]); |
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__lmax_seq = __i; |
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} |
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} |
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} |
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} |
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|
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_SeqNumber __i; |
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for (__i = 0; __i < __m; __i++) |
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{ |
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_DifferenceType __middle = (__b[__i] + __a[__i]) / 2; |
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if (__lmax && __middle < __ns[__i] && |
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__lcomp(std::make_pair(__S(__i)[__middle], __i), |
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std::make_pair(*__lmax, __lmax_seq))) |
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__a[__i] = std::min(__a[__i] + __n + 1, __ns[__i]); |
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else |
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__b[__i] -= __n + 1; |
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} |
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|
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_DifferenceType __leftsize = 0; |
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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__leftsize += __a[__i] / (__n + 1); |
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|
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_DifferenceType __skew = __rank / (__n + 1) - __leftsize; |
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|
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if (__skew > 0) |
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{ |
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// Move to the left, find smallest. |
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std::priority_queue<std::pair<_ValueType, _SeqNumber>, |
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std::vector<std::pair<_ValueType, _SeqNumber> >, |
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_LexicographicReverse<_ValueType, _SeqNumber, _Compare> > |
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__pq(__lrcomp); |
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|
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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if (__b[__i] < __ns[__i]) |
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__pq.push(std::make_pair(__S(__i)[__b[__i]], __i)); |
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|
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for (; __skew != 0 && !__pq.empty(); --__skew) |
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{ |
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_SeqNumber __source = __pq.top().second; |
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__pq.pop(); |
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|
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__a[__source] |
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= std::min(__a[__source] + __n + 1, __ns[__source]); |
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__b[__source] += __n + 1; |
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|
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if (__b[__source] < __ns[__source]) |
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__pq.push( |
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std::make_pair(__S(__source)[__b[__source]], __source)); |
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} |
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} |
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else if (__skew < 0) |
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{ |
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// Move to the right, find greatest. |
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std::priority_queue<std::pair<_ValueType, _SeqNumber>, |
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std::vector<std::pair<_ValueType, _SeqNumber> >, |
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_Lexicographic<_ValueType, _SeqNumber, _Compare> > |
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__pq(__lcomp); |
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|
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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if (__a[__i] > 0) |
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__pq.push(std::make_pair(__S(__i)[__a[__i] - 1], __i)); |
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|
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for (; __skew != 0; ++__skew) |
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{ |
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_SeqNumber __source = __pq.top().second; |
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__pq.pop(); |
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|
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__a[__source] -= __n + 1; |
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__b[__source] -= __n + 1; |
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|
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if (__a[__source] > 0) |
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__pq.push(std::make_pair( |
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__S(__source)[__a[__source] - 1], __source)); |
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} |
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} |
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} |
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|
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// Postconditions: |
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// __a[__i] == __b[__i] in most cases, except when __a[__i] has been |
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// clamped because of having reached the boundary |
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|
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// Now return the result, calculate the offset. |
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|
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// Compare the keys on both edges of the border. |
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|
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// Maximum of left edge, minimum of right edge. |
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_ValueType* __maxleft = 0; |
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_ValueType* __minright = 0; |
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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{ |
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if (__a[__i] > 0) |
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{ |
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if (!__maxleft) |
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__maxleft = &(__S(__i)[__a[__i] - 1]); |
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else |
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{ |
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// Max, favor rear sequences. |
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if (!__comp(__S(__i)[__a[__i] - 1], *__maxleft)) |
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__maxleft = &(__S(__i)[__a[__i] - 1]); |
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} |
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} |
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if (__b[__i] < __ns[__i]) |
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{ |
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if (!__minright) |
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__minright = &(__S(__i)[__b[__i]]); |
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else |
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{ |
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// Min, favor fore sequences. |
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if (__comp(__S(__i)[__b[__i]], *__minright)) |
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__minright = &(__S(__i)[__b[__i]]); |
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} |
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} |
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} |
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|
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_SeqNumber __seq = 0; |
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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__begin_offsets[__i] = __S(__i) + __a[__i]; |
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|
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delete[] __ns; |
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delete[] __a; |
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delete[] __b; |
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} |
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|
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|
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/** |
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* @brief Selects the element at a certain global __rank from several |
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* sorted sequences. |
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* |
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* The sequences are passed via a sequence of random-access |
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* iterator pairs, none of the sequences may be empty. |
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* @param __begin_seqs Begin of the sequence of iterator pairs. |
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* @param __end_seqs End of the sequence of iterator pairs. |
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* @param __rank The global rank to partition at. |
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* @param __offset The rank of the selected element in the global |
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* subsequence of elements equal to the selected element. If the |
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* selected element is unique, this number is 0. |
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* @param __comp The ordering functor, defaults to std::less. |
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*/ |
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template<typename _Tp, typename _RanSeqs, typename _RankType, |
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typename _Compare> |
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_Tp |
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multiseq_selection(_RanSeqs __begin_seqs, _RanSeqs __end_seqs, |
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_RankType __rank, |
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_RankType& __offset, _Compare __comp = std::less<_Tp>()) |
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{ |
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_GLIBCXX_CALL(__end_seqs - __begin_seqs) |
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|
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typedef typename std::iterator_traits<_RanSeqs>::value_type::first_type |
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_It; |
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typedef typename std::iterator_traits<_RanSeqs>::difference_type |
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_SeqNumber; |
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typedef typename std::iterator_traits<_It>::difference_type |
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_DifferenceType; |
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|
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_Lexicographic<_Tp, _SeqNumber, _Compare> __lcomp(__comp); |
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_LexicographicReverse<_Tp, _SeqNumber, _Compare> __lrcomp(__comp); |
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|
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// Number of sequences, number of elements in total (possibly |
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// including padding). |
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_DifferenceType __m = std::distance(__begin_seqs, __end_seqs); |
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_DifferenceType __nn = 0; |
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_DifferenceType __nmax, __n, __r; |
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|
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for (_SeqNumber __i = 0; __i < __m; __i++) |
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__nn += std::distance(__begin_seqs[__i].first, |
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__begin_seqs[__i].second); |
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|
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if (__m == 0 || __nn == 0 || __rank < 0 || __rank >= __nn) |
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{ |
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// result undefined if there is no data or __rank is outside bounds |
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throw std::exception(); |
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} |
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|
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|
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_DifferenceType* __ns = new _DifferenceType[__m]; |
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_DifferenceType* __a = new _DifferenceType[__m]; |
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_DifferenceType* __b = new _DifferenceType[__m]; |
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_DifferenceType __l; |
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|
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__ns[0] = std::distance(__begin_seqs[0].first, __begin_seqs[0].second); |
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__nmax = __ns[0]; |
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for (_SeqNumber __i = 0; __i < __m; ++__i) |
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{ |
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__ns[__i] = std::distance(__begin_seqs[__i].first, |
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__begin_seqs[__i].second); |
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__nmax = std::max(__nmax, __ns[__i]); |
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} |
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|
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__r = __rd_log2(__nmax) + 1; |
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|
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// Pad all lists to this length, at least as long as any ns[__i], |
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// equality iff __nmax = 2^__k - 1 |
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__l = __round_up_to_pow2(__r) - 1; |
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|
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for (_SeqNumber __i = 0; __i < __m; ++__i) |
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{ |
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__a[__i] = 0; |
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__b[__i] = __l; |
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} |
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__n = __l / 2; |
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|
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// Invariants: |
| 449 |
// 0 <= __a[__i] <= __ns[__i], 0 <= __b[__i] <= __l |
| 450 |
|
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#define __S(__i) (__begin_seqs[__i].first) |
| 452 |
|
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// Initial partition. |
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std::vector<std::pair<_Tp, _SeqNumber> > __sample; |
| 455 |
|
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for (_SeqNumber __i = 0; __i < __m; __i++) |
| 457 |
if (__n < __ns[__i]) |
| 458 |
__sample.push_back(std::make_pair(__S(__i)[__n], __i)); |
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__gnu_sequential::sort(__sample.begin(), __sample.end(), |
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__lcomp, sequential_tag()); |
| 461 |
|
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// Conceptual infinity. |
| 463 |
for (_SeqNumber __i = 0; __i < __m; __i++) |
| 464 |
if (__n >= __ns[__i]) |
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__sample.push_back( |
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std::make_pair(__S(__i)[0] /*__dummy element*/, __i)); |
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|
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_DifferenceType __localrank = __rank / __l; |
| 469 |
|
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_SeqNumber __j; |
| 471 |
for (__j = 0; |
| 472 |
__j < __localrank && ((__n + 1) <= __ns[__sample[__j].second]); |
| 473 |
++__j) |
| 474 |
__a[__sample[__j].second] += __n + 1; |
| 475 |
for (; __j < __m; ++__j) |
| 476 |
__b[__sample[__j].second] -= __n + 1; |
| 477 |
|
| 478 |
// Further refinement. |
| 479 |
while (__n > 0) |
| 480 |
{ |
| 481 |
__n /= 2; |
| 482 |
|
| 483 |
const _Tp* __lmax = 0; |
| 484 |
for (_SeqNumber __i = 0; __i < __m; ++__i) |
| 485 |
{ |
| 486 |
if (__a[__i] > 0) |
| 487 |
{ |
| 488 |
if (!__lmax) |
| 489 |
__lmax = &(__S(__i)[__a[__i] - 1]); |
| 490 |
else |
| 491 |
{ |
| 492 |
if (__comp(*__lmax, __S(__i)[__a[__i] - 1])) //max |
| 493 |
__lmax = &(__S(__i)[__a[__i] - 1]); |
| 494 |
} |
| 495 |
} |
| 496 |
} |
| 497 |
|
| 498 |
_SeqNumber __i; |
| 499 |
for (__i = 0; __i < __m; __i++) |
| 500 |
{ |
| 501 |
_DifferenceType __middle = (__b[__i] + __a[__i]) / 2; |
| 502 |
if (__lmax && __middle < __ns[__i] |
| 503 |
&& __comp(__S(__i)[__middle], *__lmax)) |
| 504 |
__a[__i] = std::min(__a[__i] + __n + 1, __ns[__i]); |
| 505 |
else |
| 506 |
__b[__i] -= __n + 1; |
| 507 |
} |
| 508 |
|
| 509 |
_DifferenceType __leftsize = 0; |
| 510 |
for (_SeqNumber __i = 0; __i < __m; ++__i) |
| 511 |
__leftsize += __a[__i] / (__n + 1); |
| 512 |
|
| 513 |
_DifferenceType __skew = __rank / (__n + 1) - __leftsize; |
| 514 |
|
| 515 |
if (__skew > 0) |
| 516 |
{ |
| 517 |
// Move to the left, find smallest. |
| 518 |
std::priority_queue<std::pair<_Tp, _SeqNumber>, |
| 519 |
std::vector<std::pair<_Tp, _SeqNumber> >, |
| 520 |
_LexicographicReverse<_Tp, _SeqNumber, _Compare> > |
| 521 |
__pq(__lrcomp); |
| 522 |
|
| 523 |
for (_SeqNumber __i = 0; __i < __m; ++__i) |
| 524 |
if (__b[__i] < __ns[__i]) |
| 525 |
__pq.push(std::make_pair(__S(__i)[__b[__i]], __i)); |
| 526 |
|
| 527 |
for (; __skew != 0 && !__pq.empty(); --__skew) |
| 528 |
{ |
| 529 |
_SeqNumber __source = __pq.top().second; |
| 530 |
__pq.pop(); |
| 531 |
|
| 532 |
__a[__source] |
| 533 |
= std::min(__a[__source] + __n + 1, __ns[__source]); |
| 534 |
__b[__source] += __n + 1; |
| 535 |
|
| 536 |
if (__b[__source] < __ns[__source]) |
| 537 |
__pq.push( |
| 538 |
std::make_pair(__S(__source)[__b[__source]], __source)); |
| 539 |
} |
| 540 |
} |
| 541 |
else if (__skew < 0) |
| 542 |
{ |
| 543 |
// Move to the right, find greatest. |
| 544 |
std::priority_queue<std::pair<_Tp, _SeqNumber>, |
| 545 |
std::vector<std::pair<_Tp, _SeqNumber> >, |
| 546 |
_Lexicographic<_Tp, _SeqNumber, _Compare> > __pq(__lcomp); |
| 547 |
|
| 548 |
for (_SeqNumber __i = 0; __i < __m; ++__i) |
| 549 |
if (__a[__i] > 0) |
| 550 |
__pq.push(std::make_pair(__S(__i)[__a[__i] - 1], __i)); |
| 551 |
|
| 552 |
for (; __skew != 0; ++__skew) |
| 553 |
{ |
| 554 |
_SeqNumber __source = __pq.top().second; |
| 555 |
__pq.pop(); |
| 556 |
|
| 557 |
__a[__source] -= __n + 1; |
| 558 |
__b[__source] -= __n + 1; |
| 559 |
|
| 560 |
if (__a[__source] > 0) |
| 561 |
__pq.push(std::make_pair( |
| 562 |
__S(__source)[__a[__source] - 1], __source)); |
| 563 |
} |
| 564 |
} |
| 565 |
} |
| 566 |
|
| 567 |
// Postconditions: |
| 568 |
// __a[__i] == __b[__i] in most cases, except when __a[__i] has been |
| 569 |
// clamped because of having reached the boundary |
| 570 |
|
| 571 |
// Now return the result, calculate the offset. |
| 572 |
|
| 573 |
// Compare the keys on both edges of the border. |
| 574 |
|
| 575 |
// Maximum of left edge, minimum of right edge. |
| 576 |
bool __maxleftset = false, __minrightset = false; |
| 577 |
|
| 578 |
// Impossible to avoid the warning? |
| 579 |
_Tp __maxleft, __minright; |
| 580 |
for (_SeqNumber __i = 0; __i < __m; ++__i) |
| 581 |
{ |
| 582 |
if (__a[__i] > 0) |
| 583 |
{ |
| 584 |
if (!__maxleftset) |
| 585 |
{ |
| 586 |
__maxleft = __S(__i)[__a[__i] - 1]; |
| 587 |
__maxleftset = true; |
| 588 |
} |
| 589 |
else |
| 590 |
{ |
| 591 |
// Max. |
| 592 |
if (__comp(__maxleft, __S(__i)[__a[__i] - 1])) |
| 593 |
__maxleft = __S(__i)[__a[__i] - 1]; |
| 594 |
} |
| 595 |
} |
| 596 |
if (__b[__i] < __ns[__i]) |
| 597 |
{ |
| 598 |
if (!__minrightset) |
| 599 |
{ |
| 600 |
__minright = __S(__i)[__b[__i]]; |
| 601 |
__minrightset = true; |
| 602 |
} |
| 603 |
else |
| 604 |
{ |
| 605 |
// Min. |
| 606 |
if (__comp(__S(__i)[__b[__i]], __minright)) |
| 607 |
__minright = __S(__i)[__b[__i]]; |
| 608 |
} |
| 609 |
} |
| 610 |
} |
| 611 |
|
| 612 |
// Minright is the __splitter, in any case. |
| 613 |
|
| 614 |
if (!__maxleftset || __comp(__minright, __maxleft)) |
| 615 |
{ |
| 616 |
// Good luck, everything is split unambiguously. |
| 617 |
__offset = 0; |
| 618 |
} |
| 619 |
else |
| 620 |
{ |
| 621 |
// We have to calculate an offset. |
| 622 |
__offset = 0; |
| 623 |
|
| 624 |
for (_SeqNumber __i = 0; __i < __m; ++__i) |
| 625 |
{ |
| 626 |
_DifferenceType lb |
| 627 |
= std::lower_bound(__S(__i), __S(__i) + __ns[__i], |
| 628 |
__minright, |
| 629 |
__comp) - __S(__i); |
| 630 |
__offset += __a[__i] - lb; |
| 631 |
} |
| 632 |
} |
| 633 |
|
| 634 |
delete[] __ns; |
| 635 |
delete[] __a; |
| 636 |
delete[] __b; |
| 637 |
|
| 638 |
return __minright; |
| 639 |
} |
| 640 |
} |
| 641 |
|
| 642 |
#undef __S |
| 643 |
|
| 644 |
#endif /* _GLIBCXX_PARALLEL_MULTISEQ_SELECTION_H */ |
