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// Numeric extensions -*- C++ -*- |
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|
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// Copyright (C) 2002-2021 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 |
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// terms of the GNU General Public License as published by the |
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// Free Software Foundation; either version 3, or (at your option) |
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// any later version. |
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|
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// This library is distributed in the hope that it will be useful, |
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// but WITHOUT ANY WARRANTY; without even the implied warranty of |
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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// GNU 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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/* |
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* |
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* Copyright (c) 1994 |
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* Hewlett-Packard Company |
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* |
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* Permission to use, copy, modify, distribute and sell this software |
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* and its documentation for any purpose is hereby granted without fee, |
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* provided that the above copyright notice appear in all copies and |
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* that both that copyright notice and this permission notice appear |
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* in supporting documentation. Hewlett-Packard Company makes no |
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* representations about the suitability of this software for any |
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* purpose. It is provided "as is" without express or implied warranty. |
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* |
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* |
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* Copyright (c) 1996 |
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* Silicon Graphics Computer Systems, Inc. |
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* |
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* Permission to use, copy, modify, distribute and sell this software |
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* and its documentation for any purpose is hereby granted without fee, |
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* provided that the above copyright notice appear in all copies and |
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* that both that copyright notice and this permission notice appear |
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* in supporting documentation. Silicon Graphics makes no |
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* representations about the suitability of this software for any |
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* purpose. It is provided "as is" without express or implied warranty. |
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*/ |
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|
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/** @file ext/numeric |
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* This file is a GNU extension to the Standard C++ Library (possibly |
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* containing extensions from the HP/SGI STL subset). |
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*/ |
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|
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#ifndef _EXT_NUMERIC |
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#define _EXT_NUMERIC 1 |
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|
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#pragma GCC system_header |
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|
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#include <bits/concept_check.h> |
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#include <numeric> |
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|
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#include <ext/functional> // For identity_element |
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|
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namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) |
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{ |
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_GLIBCXX_BEGIN_NAMESPACE_VERSION |
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|
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// Returns __x ** __n, where __n >= 0. _Note that "multiplication" |
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// is required to be associative, but not necessarily commutative. |
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template<typename _Tp, typename _Integer, typename _MonoidOperation> |
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_Tp |
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__power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op) |
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{ |
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if (__n == 0) |
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return identity_element(__monoid_op); |
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else |
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{ |
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while ((__n & 1) == 0) |
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{ |
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__n >>= 1; |
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__x = __monoid_op(__x, __x); |
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} |
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|
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_Tp __result = __x; |
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__n >>= 1; |
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while (__n != 0) |
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{ |
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__x = __monoid_op(__x, __x); |
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if ((__n & 1) != 0) |
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__result = __monoid_op(__result, __x); |
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__n >>= 1; |
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} |
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return __result; |
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} |
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} |
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|
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template<typename _Tp, typename _Integer> |
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inline _Tp |
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__power(_Tp __x, _Integer __n) |
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{ return __power(__x, __n, std::multiplies<_Tp>()); } |
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|
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/** |
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* This is an SGI extension. |
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* @ingroup SGIextensions |
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* @doctodo |
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*/ |
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// Alias for the internal name __power. Note that power is an extension, |
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// not part of the C++ standard. |
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template<typename _Tp, typename _Integer, typename _MonoidOperation> |
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inline _Tp |
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power(_Tp __x, _Integer __n, _MonoidOperation __monoid_op) |
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{ return __power(__x, __n, __monoid_op); } |
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|
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/** |
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* This is an SGI extension. |
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* @ingroup SGIextensions |
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* @doctodo |
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*/ |
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template<typename _Tp, typename _Integer> |
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inline _Tp |
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power(_Tp __x, _Integer __n) |
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{ return __power(__x, __n); } |
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|
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#if __cplusplus >= 201103L |
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using std::iota; |
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#else |
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/** |
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* This is an SGI extension. |
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* @ingroup SGIextensions |
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* @doctodo |
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*/ |
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// iota is not part of the standard until C++11. It is an extension. |
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template<typename _ForwardIter, typename _Tp> |
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void |
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iota(_ForwardIter __first, _ForwardIter __last, _Tp __value) |
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{ |
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// concept requirements |
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__glibcxx_function_requires(_Mutable_ForwardIteratorConcept<_ForwardIter>) |
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__glibcxx_function_requires(_ConvertibleConcept<_Tp, |
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typename std::iterator_traits<_ForwardIter>::value_type>) |
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|
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while (__first != __last) |
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*__first++ = __value++; |
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} |
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#endif // C++11 |
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|
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_GLIBCXX_END_NAMESPACE_VERSION |
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} // namespace |
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|
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#endif |
