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Diffstat (limited to 'libstdc++-v3/include/ext/algorithm')
| -rw-r--r-- | libstdc++-v3/include/ext/algorithm | 605 |
1 files changed, 605 insertions, 0 deletions
diff --git a/libstdc++-v3/include/ext/algorithm b/libstdc++-v3/include/ext/algorithm new file mode 100644 index 000000000..417a03ab9 --- /dev/null +++ b/libstdc++-v3/include/ext/algorithm @@ -0,0 +1,605 @@ +// Algorithm extensions -*- C++ -*- + +// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, +// 2009, 2010, 2011 +// Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// Under Section 7 of GPL version 3, you are granted additional +// permissions described in the GCC Runtime Library Exception, version +// 3.1, as published by the Free Software Foundation. + +// You should have received a copy of the GNU General Public License and +// a copy of the GCC Runtime Library Exception along with this program; +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +// <http://www.gnu.org/licenses/>. + +/* + * + * Copyright (c) 1994 + * Hewlett-Packard Company + * + * Permission to use, copy, modify, distribute and sell this software + * and its documentation for any purpose is hereby granted without fee, + * provided that the above copyright notice appear in all copies and + * that both that copyright notice and this permission notice appear + * in supporting documentation. Hewlett-Packard Company makes no + * representations about the suitability of this software for any + * purpose. It is provided "as is" without express or implied warranty. + * + * + * Copyright (c) 1996 + * Silicon Graphics Computer Systems, Inc. + * + * Permission to use, copy, modify, distribute and sell this software + * and its documentation for any purpose is hereby granted without fee, + * provided that the above copyright notice appear in all copies and + * that both that copyright notice and this permission notice appear + * in supporting documentation. Silicon Graphics makes no + * representations about the suitability of this software for any + * purpose. It is provided "as is" without express or implied warranty. + */ + +/** @file ext/algorithm + * This file is a GNU extension to the Standard C++ Library (possibly + * containing extensions from the HP/SGI STL subset). + */ + +#ifndef _EXT_ALGORITHM +#define _EXT_ALGORITHM 1 + +#pragma GCC system_header + +#include <algorithm> + +namespace __gnu_cxx _GLIBCXX_VISIBILITY(default) +{ +_GLIBCXX_BEGIN_NAMESPACE_VERSION + + using std::ptrdiff_t; + using std::min; + using std::pair; + using std::input_iterator_tag; + using std::random_access_iterator_tag; + using std::iterator_traits; + + //-------------------------------------------------- + // copy_n (not part of the C++ standard) + + template<typename _InputIterator, typename _Size, typename _OutputIterator> + pair<_InputIterator, _OutputIterator> + __copy_n(_InputIterator __first, _Size __count, + _OutputIterator __result, + input_iterator_tag) + { + for ( ; __count > 0; --__count) + { + *__result = *__first; + ++__first; + ++__result; + } + return pair<_InputIterator, _OutputIterator>(__first, __result); + } + + template<typename _RAIterator, typename _Size, typename _OutputIterator> + inline pair<_RAIterator, _OutputIterator> + __copy_n(_RAIterator __first, _Size __count, + _OutputIterator __result, + random_access_iterator_tag) + { + _RAIterator __last = __first + __count; + return pair<_RAIterator, _OutputIterator>(__last, std::copy(__first, + __last, + __result)); + } + + /** + * @brief Copies the range [first,first+count) into [result,result+count). + * @param first An input iterator. + * @param count The number of elements to copy. + * @param result An output iterator. + * @return A std::pair composed of first+count and result+count. + * + * This is an SGI extension. + * This inline function will boil down to a call to @c memmove whenever + * possible. Failing that, if random access iterators are passed, then the + * loop count will be known (and therefore a candidate for compiler + * optimizations such as unrolling). + * @ingroup SGIextensions + */ + template<typename _InputIterator, typename _Size, typename _OutputIterator> + inline pair<_InputIterator, _OutputIterator> + copy_n(_InputIterator __first, _Size __count, _OutputIterator __result) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + typename iterator_traits<_InputIterator>::value_type>) + + return __gnu_cxx::__copy_n(__first, __count, __result, + std::__iterator_category(__first)); + } + + template<typename _InputIterator1, typename _InputIterator2> + int + __lexicographical_compare_3way(_InputIterator1 __first1, + _InputIterator1 __last1, + _InputIterator2 __first2, + _InputIterator2 __last2) + { + while (__first1 != __last1 && __first2 != __last2) + { + if (*__first1 < *__first2) + return -1; + if (*__first2 < *__first1) + return 1; + ++__first1; + ++__first2; + } + if (__first2 == __last2) + return !(__first1 == __last1); + else + return -1; + } + + inline int + __lexicographical_compare_3way(const unsigned char* __first1, + const unsigned char* __last1, + const unsigned char* __first2, + const unsigned char* __last2) + { + const ptrdiff_t __len1 = __last1 - __first1; + const ptrdiff_t __len2 = __last2 - __first2; + const int __result = __builtin_memcmp(__first1, __first2, + min(__len1, __len2)); + return __result != 0 ? __result + : (__len1 == __len2 ? 0 : (__len1 < __len2 ? -1 : 1)); + } + + inline int + __lexicographical_compare_3way(const char* __first1, const char* __last1, + const char* __first2, const char* __last2) + { +#if CHAR_MAX == SCHAR_MAX + return __lexicographical_compare_3way((const signed char*) __first1, + (const signed char*) __last1, + (const signed char*) __first2, + (const signed char*) __last2); +#else + return __lexicographical_compare_3way((const unsigned char*) __first1, + (const unsigned char*) __last1, + (const unsigned char*) __first2, + (const unsigned char*) __last2); +#endif + } + + /** + * @brief @c memcmp on steroids. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @param last2 An input iterator. + * @return An int, as with @c memcmp. + * + * The return value will be less than zero if the first range is + * <em>lexigraphically less than</em> the second, greater than zero + * if the second range is <em>lexigraphically less than</em> the + * first, and zero otherwise. + * This is an SGI extension. + * @ingroup SGIextensions + */ + template<typename _InputIterator1, typename _InputIterator2> + int + lexicographical_compare_3way(_InputIterator1 __first1, + _InputIterator1 __last1, + _InputIterator2 __first2, + _InputIterator2 __last2) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) + __glibcxx_function_requires(_LessThanComparableConcept< + typename iterator_traits<_InputIterator1>::value_type>) + __glibcxx_function_requires(_LessThanComparableConcept< + typename iterator_traits<_InputIterator2>::value_type>) + __glibcxx_requires_valid_range(__first1, __last1); + __glibcxx_requires_valid_range(__first2, __last2); + + return __lexicographical_compare_3way(__first1, __last1, __first2, + __last2); + } + + // count and count_if: this version, whose return type is void, was present + // in the HP STL, and is retained as an extension for backward compatibility. + template<typename _InputIterator, typename _Tp, typename _Size> + void + count(_InputIterator __first, _InputIterator __last, + const _Tp& __value, + _Size& __n) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_EqualityComparableConcept< + typename iterator_traits<_InputIterator>::value_type >) + __glibcxx_function_requires(_EqualityComparableConcept<_Tp>) + __glibcxx_requires_valid_range(__first, __last); + + for ( ; __first != __last; ++__first) + if (*__first == __value) + ++__n; + } + + template<typename _InputIterator, typename _Predicate, typename _Size> + void + count_if(_InputIterator __first, _InputIterator __last, + _Predicate __pred, + _Size& __n) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_UnaryPredicateConcept<_Predicate, + typename iterator_traits<_InputIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + for ( ; __first != __last; ++__first) + if (__pred(*__first)) + ++__n; + } + + // random_sample and random_sample_n (extensions, not part of the standard). + + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _ForwardIterator, typename _OutputIterator, + typename _Distance> + _OutputIterator + random_sample_n(_ForwardIterator __first, _ForwardIterator __last, + _OutputIterator __out, const _Distance __n) + { + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + _Distance __remaining = std::distance(__first, __last); + _Distance __m = min(__n, __remaining); + + while (__m > 0) + { + if ((std::rand() % __remaining) < __m) + { + *__out = *__first; + ++__out; + --__m; + } + --__remaining; + ++__first; + } + return __out; + } + + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _ForwardIterator, typename _OutputIterator, + typename _Distance, typename _RandomNumberGenerator> + _OutputIterator + random_sample_n(_ForwardIterator __first, _ForwardIterator __last, + _OutputIterator __out, const _Distance __n, + _RandomNumberGenerator& __rand) + { + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_function_requires(_UnaryFunctionConcept< + _RandomNumberGenerator, _Distance, _Distance>) + __glibcxx_requires_valid_range(__first, __last); + + _Distance __remaining = std::distance(__first, __last); + _Distance __m = min(__n, __remaining); + + while (__m > 0) + { + if (__rand(__remaining) < __m) + { + *__out = *__first; + ++__out; + --__m; + } + --__remaining; + ++__first; + } + return __out; + } + + template<typename _InputIterator, typename _RandomAccessIterator, + typename _Distance> + _RandomAccessIterator + __random_sample(_InputIterator __first, _InputIterator __last, + _RandomAccessIterator __out, + const _Distance __n) + { + _Distance __m = 0; + _Distance __t = __n; + for ( ; __first != __last && __m < __n; ++__m, ++__first) + __out[__m] = *__first; + + while (__first != __last) + { + ++__t; + _Distance __M = std::rand() % (__t); + if (__M < __n) + __out[__M] = *__first; + ++__first; + } + return __out + __m; + } + + template<typename _InputIterator, typename _RandomAccessIterator, + typename _RandomNumberGenerator, typename _Distance> + _RandomAccessIterator + __random_sample(_InputIterator __first, _InputIterator __last, + _RandomAccessIterator __out, + _RandomNumberGenerator& __rand, + const _Distance __n) + { + // concept requirements + __glibcxx_function_requires(_UnaryFunctionConcept< + _RandomNumberGenerator, _Distance, _Distance>) + + _Distance __m = 0; + _Distance __t = __n; + for ( ; __first != __last && __m < __n; ++__m, ++__first) + __out[__m] = *__first; + + while (__first != __last) + { + ++__t; + _Distance __M = __rand(__t); + if (__M < __n) + __out[__M] = *__first; + ++__first; + } + return __out + __m; + } + + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _InputIterator, typename _RandomAccessIterator> + inline _RandomAccessIterator + random_sample(_InputIterator __first, _InputIterator __last, + _RandomAccessIterator __out_first, + _RandomAccessIterator __out_last) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_requires_valid_range(__first, __last); + __glibcxx_requires_valid_range(__out_first, __out_last); + + return __random_sample(__first, __last, + __out_first, __out_last - __out_first); + } + + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _InputIterator, typename _RandomAccessIterator, + typename _RandomNumberGenerator> + inline _RandomAccessIterator + random_sample(_InputIterator __first, _InputIterator __last, + _RandomAccessIterator __out_first, + _RandomAccessIterator __out_last, + _RandomNumberGenerator& __rand) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_requires_valid_range(__first, __last); + __glibcxx_requires_valid_range(__out_first, __out_last); + + return __random_sample(__first, __last, + __out_first, __rand, + __out_last - __out_first); + } + +#ifdef __GXX_EXPERIMENTAL_CXX0X__ + using std::is_heap; +#else + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _RandomAccessIterator> + inline bool + is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last) + { + // concept requirements + __glibcxx_function_requires(_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_function_requires(_LessThanComparableConcept< + typename iterator_traits<_RandomAccessIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + return std::__is_heap(__first, __last - __first); + } + + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _RandomAccessIterator, typename _StrictWeakOrdering> + inline bool + is_heap(_RandomAccessIterator __first, _RandomAccessIterator __last, + _StrictWeakOrdering __comp) + { + // concept requirements + __glibcxx_function_requires(_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_StrictWeakOrdering, + typename iterator_traits<_RandomAccessIterator>::value_type, + typename iterator_traits<_RandomAccessIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + return std::__is_heap(__first, __comp, __last - __first); + } +#endif + +#ifdef __GXX_EXPERIMENTAL_CXX0X__ + using std::is_sorted; +#else + // is_sorted, a predicated testing whether a range is sorted in + // nondescending order. This is an extension, not part of the C++ + // standard. + + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _ForwardIterator> + bool + is_sorted(_ForwardIterator __first, _ForwardIterator __last) + { + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_LessThanComparableConcept< + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + if (__first == __last) + return true; + + _ForwardIterator __next = __first; + for (++__next; __next != __last; __first = __next, ++__next) + if (*__next < *__first) + return false; + return true; + } + + /** + * This is an SGI extension. + * @ingroup SGIextensions + * @doctodo + */ + template<typename _ForwardIterator, typename _StrictWeakOrdering> + bool + is_sorted(_ForwardIterator __first, _ForwardIterator __last, + _StrictWeakOrdering __comp) + { + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_StrictWeakOrdering, + typename iterator_traits<_ForwardIterator>::value_type, + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + if (__first == __last) + return true; + + _ForwardIterator __next = __first; + for (++__next; __next != __last; __first = __next, ++__next) + if (__comp(*__next, *__first)) + return false; + return true; + } +#endif // __GXX_EXPERIMENTAL_CXX0X__ + + /** + * @brief Find the median of three values. + * @param a A value. + * @param b A value. + * @param c A value. + * @return One of @p a, @p b or @p c. + * + * If @c {l,m,n} is some convolution of @p {a,b,c} such that @c l<=m<=n + * then the value returned will be @c m. + * This is an SGI extension. + * @ingroup SGIextensions + */ + template<typename _Tp> + const _Tp& + __median(const _Tp& __a, const _Tp& __b, const _Tp& __c) + { + // concept requirements + __glibcxx_function_requires(_LessThanComparableConcept<_Tp>) + if (__a < __b) + if (__b < __c) + return __b; + else if (__a < __c) + return __c; + else + return __a; + else if (__a < __c) + return __a; + else if (__b < __c) + return __c; + else + return __b; + } + + /** + * @brief Find the median of three values using a predicate for comparison. + * @param a A value. + * @param b A value. + * @param c A value. + * @param comp A binary predicate. + * @return One of @p a, @p b or @p c. + * + * If @c {l,m,n} is some convolution of @p {a,b,c} such that @p comp(l,m) + * and @p comp(m,n) are both true then the value returned will be @c m. + * This is an SGI extension. + * @ingroup SGIextensions + */ + template<typename _Tp, typename _Compare> + const _Tp& + __median(const _Tp& __a, const _Tp& __b, const _Tp& __c, _Compare __comp) + { + // concept requirements + __glibcxx_function_requires(_BinaryFunctionConcept<_Compare, bool, + _Tp, _Tp>) + if (__comp(__a, __b)) + if (__comp(__b, __c)) + return __b; + else if (__comp(__a, __c)) + return __c; + else + return __a; + else if (__comp(__a, __c)) + return __a; + else if (__comp(__b, __c)) + return __c; + else + return __b; + } + +_GLIBCXX_END_NAMESPACE_VERSION +} // namespace + +#endif /* _EXT_ALGORITHM */ |