From: Paolo Carlini Date: Sun, 20 May 2007 17:48:36 +0000 (+0000) Subject: stl_algo.h: Shuffle the functions to better match the order in the standard. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=da5a2efd39b67a36c4e70f059ffbbb6103606f3e;p=gcc.git stl_algo.h: Shuffle the functions to better match the order in the standard. 2007-05-20 Paolo Carlini * include/bits/stl_algo.h: Shuffle the functions to better match the order in the standard. From-SVN: r124874 --- diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 6d5c5d413e2..83ee0bfc7b3 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,3 +1,8 @@ +2007-05-20 Paolo Carlini + + * include/bits/stl_algo.h: Shuffle the functions to better match the + order in the standard. + 2007-05-17 Paolo Carlini * config/locale/gnu/c_locale.h: Do not include . diff --git a/libstdc++-v3/include/bits/stl_algo.h b/libstdc++-v3/include/bits/stl_algo.h index 1d743ab94b4..fe4024a918b 100644 --- a/libstdc++-v3/include/bits/stl_algo.h +++ b/libstdc++-v3/include/bits/stl_algo.h @@ -156,7 +156,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) // concept requirements __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) __glibcxx_requires_valid_range(__first, __last); - for ( ; __first != __last; ++__first) + for (; __first != __last; ++__first) __f(*__first); return __f; } @@ -204,7 +204,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_RandomAccessIterator>::difference_type __trip_count = (__last - __first) >> 2; - for ( ; __trip_count > 0 ; --__trip_count) + for (; __trip_count > 0; --__trip_count) { if (*__first == __val) return __first; @@ -256,7 +256,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_RandomAccessIterator>::difference_type __trip_count = (__last - __first) >> 2; - for ( ; __trip_count > 0 ; --__trip_count) + for (; __trip_count > 0; --__trip_count) { if (__pred(*__first)) return __first; @@ -339,6 +339,79 @@ _GLIBCXX_BEGIN_NAMESPACE(std) std::__iterator_category(__first)); } + /** + * @brief Find element from a set in a sequence. + * @param first1 Start of range to search. + * @param last1 End of range to search. + * @param first2 Start of match candidates. + * @param last2 End of match candidates. + * @return The first iterator @c i in the range + * @p [first1,last1) such that @c *i == @p *(i2) such that i2 is an + * interator in [first2,last2), or @p last1 if no such iterator exists. + * + * Searches the range @p [first1,last1) for an element that is equal to + * some element in the range [first2,last2). If found, returns an iterator + * in the range [first1,last1), otherwise returns @p last1. + */ + template + _InputIterator + find_first_of(_InputIterator __first1, _InputIterator __last1, + _ForwardIterator __first2, _ForwardIterator __last2) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_EqualOpConcept< + typename iterator_traits<_InputIterator>::value_type, + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first1, __last1); + __glibcxx_requires_valid_range(__first2, __last2); + + for (; __first1 != __last1; ++__first1) + for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter) + if (*__first1 == *__iter) + return __first1; + return __last1; + } + + /** + * @brief Find element from a set in a sequence using a predicate. + * @param first1 Start of range to search. + * @param last1 End of range to search. + * @param first2 Start of match candidates. + * @param last2 End of match candidates. + * @param comp Predicate to use. + * @return The first iterator @c i in the range + * @p [first1,last1) such that @c comp(*i, @p *(i2)) is true and i2 is an + * interator in [first2,last2), or @p last1 if no such iterator exists. + * + * Searches the range @p [first1,last1) for an element that is equal to + * some element in the range [first2,last2). If found, returns an iterator in + * the range [first1,last1), otherwise returns @p last1. + */ + template + _InputIterator + find_first_of(_InputIterator __first1, _InputIterator __last1, + _ForwardIterator __first2, _ForwardIterator __last2, + _BinaryPredicate __comp) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, + typename iterator_traits<_InputIterator>::value_type, + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first1, __last1); + __glibcxx_requires_valid_range(__first2, __last2); + + for (; __first1 != __last1; ++__first1) + for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter) + if (__comp(*__first1, *__iter)) + return __first1; + return __last1; + } + /** * @brief Find two adjacent values in a sequence that are equal. * @param first A forward iterator. @@ -419,7 +492,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_InputIterator>::value_type, _Tp>) __glibcxx_requires_valid_range(__first, __last); typename iterator_traits<_InputIterator>::difference_type __n = 0; - for ( ; __first != __last; ++__first) + for (; __first != __last; ++__first) if (*__first == __value) ++__n; return __n; @@ -443,7 +516,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_InputIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); typename iterator_traits<_InputIterator>::difference_type __n = 0; - for ( ; __first != __last; ++__first) + for (; __first != __last; ++__first) if (__pred(*__first)) ++__n; return __n; @@ -929,112 +1002,328 @@ _GLIBCXX_BEGIN_NAMESPACE(std) std::__iterator_category(__first)); } - /** - * @brief Perform an operation on a sequence. - * @param first An input iterator. - * @param last An input iterator. - * @param result An output iterator. - * @param unary_op A unary operator. - * @return An output iterator equal to @p result+(last-first). - * - * Applies the operator to each element in the input range and assigns - * the results to successive elements of the output sequence. - * Evaluates @p *(result+N)=unary_op(*(first+N)) for each @c N in the - * range @p [0,last-first). - * - * @p unary_op must not alter its argument. - */ - template - _OutputIterator - transform(_InputIterator __first, _InputIterator __last, - _OutputIterator __result, _UnaryOperation __unary_op) + // find_end for forward iterators. + template + _ForwardIterator1 + __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, + _ForwardIterator2 __first2, _ForwardIterator2 __last2, + forward_iterator_tag, forward_iterator_tag) { - // concept requirements - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) - __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, - // "the type returned by a _UnaryOperation" - __typeof__(__unary_op(*__first))>) - __glibcxx_requires_valid_range(__first, __last); + if (__first2 == __last2) + return __last1; + else + { + _ForwardIterator1 __result = __last1; + while (1) + { + _ForwardIterator1 __new_result + = std::search(__first1, __last1, __first2, __last2); + if (__new_result == __last1) + return __result; + else + { + __result = __new_result; + __first1 = __new_result; + ++__first1; + } + } + } + } - for ( ; __first != __last; ++__first, ++__result) - *__result = __unary_op(*__first); - return __result; + template + _ForwardIterator1 + __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, + _ForwardIterator2 __first2, _ForwardIterator2 __last2, + forward_iterator_tag, forward_iterator_tag, + _BinaryPredicate __comp) + { + if (__first2 == __last2) + return __last1; + else + { + _ForwardIterator1 __result = __last1; + while (1) + { + _ForwardIterator1 __new_result + = std::search(__first1, __last1, __first2, __last2, __comp); + if (__new_result == __last1) + return __result; + else + { + __result = __new_result; + __first1 = __new_result; + ++__first1; + } + } + } } - /** - * @brief Perform an operation on corresponding elements of two sequences. - * @param first1 An input iterator. - * @param last1 An input iterator. - * @param first2 An input iterator. - * @param result An output iterator. - * @param binary_op A binary operator. - * @return An output iterator equal to @p result+(last-first). - * - * Applies the operator to the corresponding elements in the two - * input ranges and assigns the results to successive elements of the - * output sequence. - * Evaluates @p *(result+N)=binary_op(*(first1+N),*(first2+N)) for each - * @c N in the range @p [0,last1-first1). - * - * @p binary_op must not alter either of its arguments. - */ - template - _OutputIterator - transform(_InputIterator1 __first1, _InputIterator1 __last1, - _InputIterator2 __first2, _OutputIterator __result, - _BinaryOperation __binary_op) + // find_end for bidirectional iterators (much faster). + template + _BidirectionalIterator1 + __find_end(_BidirectionalIterator1 __first1, + _BidirectionalIterator1 __last1, + _BidirectionalIterator2 __first2, + _BidirectionalIterator2 __last2, + bidirectional_iterator_tag, bidirectional_iterator_tag) { // concept requirements - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) - __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, - // "the type returned by a _BinaryOperation" - __typeof__(__binary_op(*__first1,*__first2))>) - __glibcxx_requires_valid_range(__first1, __last1); + __glibcxx_function_requires(_BidirectionalIteratorConcept< + _BidirectionalIterator1>) + __glibcxx_function_requires(_BidirectionalIteratorConcept< + _BidirectionalIterator2>) - for ( ; __first1 != __last1; ++__first1, ++__first2, ++__result) - *__result = __binary_op(*__first1, *__first2); - return __result; + typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1; + typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2; + + _RevIterator1 __rlast1(__first1); + _RevIterator2 __rlast2(__first2); + _RevIterator1 __rresult = std::search(_RevIterator1(__last1), __rlast1, + _RevIterator2(__last2), __rlast2); + + if (__rresult == __rlast1) + return __last1; + else + { + _BidirectionalIterator1 __result = __rresult.base(); + std::advance(__result, -std::distance(__first2, __last2)); + return __result; + } } - /** - * @brief Replace each occurrence of one value in a sequence with another - * value. - * @param first A forward iterator. - * @param last A forward iterator. - * @param old_value The value to be replaced. - * @param new_value The replacement value. - * @return replace() returns no value. - * - * For each iterator @c i in the range @p [first,last) if @c *i == - * @p old_value then the assignment @c *i = @p new_value is performed. - */ - template - void - replace(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __old_value, const _Tp& __new_value) + template + _BidirectionalIterator1 + __find_end(_BidirectionalIterator1 __first1, + _BidirectionalIterator1 __last1, + _BidirectionalIterator2 __first2, + _BidirectionalIterator2 __last2, + bidirectional_iterator_tag, bidirectional_iterator_tag, + _BinaryPredicate __comp) { // concept requirements - __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< - _ForwardIterator>) - __glibcxx_function_requires(_EqualOpConcept< - typename iterator_traits<_ForwardIterator>::value_type, _Tp>) - __glibcxx_function_requires(_ConvertibleConcept<_Tp, - typename iterator_traits<_ForwardIterator>::value_type>) - __glibcxx_requires_valid_range(__first, __last); + __glibcxx_function_requires(_BidirectionalIteratorConcept< + _BidirectionalIterator1>) + __glibcxx_function_requires(_BidirectionalIteratorConcept< + _BidirectionalIterator2>) - for ( ; __first != __last; ++__first) - if (*__first == __old_value) - *__first = __new_value; - } + typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1; + typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2; - /** - * @brief Replace each value in a sequence for which a predicate returns - * true with another value. - * @param first A forward iterator. - * @param last A forward iterator. + _RevIterator1 __rlast1(__first1); + _RevIterator2 __rlast2(__first2); + _RevIterator1 __rresult = std::search(_RevIterator1(__last1), __rlast1, + _RevIterator2(__last2), __rlast2, + __comp); + + if (__rresult == __rlast1) + return __last1; + else + { + _BidirectionalIterator1 __result = __rresult.base(); + std::advance(__result, -std::distance(__first2, __last2)); + return __result; + } + } + + /** + * @brief Find last matching subsequence in a sequence. + * @param first1 Start of range to search. + * @param last1 End of range to search. + * @param first2 Start of sequence to match. + * @param last2 End of sequence to match. + * @return The last iterator @c i in the range + * @p [first1,last1-(last2-first2)) such that @c *(i+N) == @p *(first2+N) + * for each @c N in the range @p [0,last2-first2), or @p last1 if no + * such iterator exists. + * + * Searches the range @p [first1,last1) for a sub-sequence that compares + * equal value-by-value with the sequence given by @p [first2,last2) and + * returns an iterator to the first element of the sub-sequence, or + * @p last1 if the sub-sequence is not found. The sub-sequence will be the + * last such subsequence contained in [first,last1). + * + * Because the sub-sequence must lie completely within the range + * @p [first1,last1) it must start at a position less than + * @p last1-(last2-first2) where @p last2-first2 is the length of the + * sub-sequence. + * This means that the returned iterator @c i will be in the range + * @p [first1,last1-(last2-first2)) + */ + template + inline _ForwardIterator1 + find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, + _ForwardIterator2 __first2, _ForwardIterator2 __last2) + { + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>) + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>) + __glibcxx_function_requires(_EqualOpConcept< + typename iterator_traits<_ForwardIterator1>::value_type, + typename iterator_traits<_ForwardIterator2>::value_type>) + __glibcxx_requires_valid_range(__first1, __last1); + __glibcxx_requires_valid_range(__first2, __last2); + + return std::__find_end(__first1, __last1, __first2, __last2, + std::__iterator_category(__first1), + std::__iterator_category(__first2)); + } + + /** + * @brief Find last matching subsequence in a sequence using a predicate. + * @param first1 Start of range to search. + * @param last1 End of range to search. + * @param first2 Start of sequence to match. + * @param last2 End of sequence to match. + * @param comp The predicate to use. + * @return The last iterator @c i in the range + * @p [first1,last1-(last2-first2)) such that @c predicate(*(i+N), @p + * (first2+N)) is true for each @c N in the range @p [0,last2-first2), or + * @p last1 if no such iterator exists. + * + * Searches the range @p [first1,last1) for a sub-sequence that compares + * equal value-by-value with the sequence given by @p [first2,last2) using + * comp as a predicate and returns an iterator to the first element of the + * sub-sequence, or @p last1 if the sub-sequence is not found. The + * sub-sequence will be the last such subsequence contained in + * [first,last1). + * + * Because the sub-sequence must lie completely within the range + * @p [first1,last1) it must start at a position less than + * @p last1-(last2-first2) where @p last2-first2 is the length of the + * sub-sequence. + * This means that the returned iterator @c i will be in the range + * @p [first1,last1-(last2-first2)) + */ + template + inline _ForwardIterator1 + find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, + _ForwardIterator2 __first2, _ForwardIterator2 __last2, + _BinaryPredicate __comp) + { + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>) + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>) + __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, + typename iterator_traits<_ForwardIterator1>::value_type, + typename iterator_traits<_ForwardIterator2>::value_type>) + __glibcxx_requires_valid_range(__first1, __last1); + __glibcxx_requires_valid_range(__first2, __last2); + + return std::__find_end(__first1, __last1, __first2, __last2, + std::__iterator_category(__first1), + std::__iterator_category(__first2), + __comp); + } + + /** + * @brief Perform an operation on a sequence. + * @param first An input iterator. + * @param last An input iterator. + * @param result An output iterator. + * @param unary_op A unary operator. + * @return An output iterator equal to @p result+(last-first). + * + * Applies the operator to each element in the input range and assigns + * the results to successive elements of the output sequence. + * Evaluates @p *(result+N)=unary_op(*(first+N)) for each @c N in the + * range @p [0,last-first). + * + * @p unary_op must not alter its argument. + */ + template + _OutputIterator + transform(_InputIterator __first, _InputIterator __last, + _OutputIterator __result, _UnaryOperation __unary_op) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + // "the type returned by a _UnaryOperation" + __typeof__(__unary_op(*__first))>) + __glibcxx_requires_valid_range(__first, __last); + + for (; __first != __last; ++__first, ++__result) + *__result = __unary_op(*__first); + return __result; + } + + /** + * @brief Perform an operation on corresponding elements of two sequences. + * @param first1 An input iterator. + * @param last1 An input iterator. + * @param first2 An input iterator. + * @param result An output iterator. + * @param binary_op A binary operator. + * @return An output iterator equal to @p result+(last-first). + * + * Applies the operator to the corresponding elements in the two + * input ranges and assigns the results to successive elements of the + * output sequence. + * Evaluates @p *(result+N)=binary_op(*(first1+N),*(first2+N)) for each + * @c N in the range @p [0,last1-first1). + * + * @p binary_op must not alter either of its arguments. + */ + template + _OutputIterator + transform(_InputIterator1 __first1, _InputIterator1 __last1, + _InputIterator2 __first2, _OutputIterator __result, + _BinaryOperation __binary_op) + { + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + // "the type returned by a _BinaryOperation" + __typeof__(__binary_op(*__first1,*__first2))>) + __glibcxx_requires_valid_range(__first1, __last1); + + for (; __first1 != __last1; ++__first1, ++__first2, ++__result) + *__result = __binary_op(*__first1, *__first2); + return __result; + } + + /** + * @brief Replace each occurrence of one value in a sequence with another + * value. + * @param first A forward iterator. + * @param last A forward iterator. + * @param old_value The value to be replaced. + * @param new_value The replacement value. + * @return replace() returns no value. + * + * For each iterator @c i in the range @p [first,last) if @c *i == + * @p old_value then the assignment @c *i = @p new_value is performed. + */ + template + void + replace(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __old_value, const _Tp& __new_value) + { + // concept requirements + __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< + _ForwardIterator>) + __glibcxx_function_requires(_EqualOpConcept< + typename iterator_traits<_ForwardIterator>::value_type, _Tp>) + __glibcxx_function_requires(_ConvertibleConcept<_Tp, + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + for (; __first != __last; ++__first) + if (*__first == __old_value) + *__first = __new_value; + } + + /** + * @brief Replace each value in a sequence for which a predicate returns + * true with another value. + * @param first A forward iterator. + * @param last A forward iterator. * @param pred A predicate. * @param new_value The replacement value. * @return replace_if() returns no value. @@ -1056,7 +1345,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_ForwardIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); - for ( ; __first != __last; ++__first) + for (; __first != __last; ++__first) if (__pred(*__first)) *__first = __new_value; } @@ -1089,7 +1378,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_InputIterator>::value_type, _Tp>) __glibcxx_requires_valid_range(__first, __last); - for ( ; __first != __last; ++__first, ++__result) + for (; __first != __last; ++__first, ++__result) if (*__first == __old_value) *__result = __new_value; else @@ -1126,7 +1415,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_InputIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); - for ( ; __first != __last; ++__first, ++__result) + for (; __first != __last; ++__first, ++__result) if (__pred(*__first)) *__result = __new_value; else @@ -1156,7 +1445,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_ForwardIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); - for ( ; __first != __last; ++__first) + for (; __first != __last; ++__first) *__first = __gen(); } @@ -1180,7 +1469,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) // "the type returned by a _Generator" __typeof__(__gen())>) - for ( ; __n > 0; --__n, ++__first) + for (; __n > 0; --__n, ++__first) *__first = __gen(); return __first; } @@ -1211,7 +1500,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_InputIterator>::value_type, _Tp>) __glibcxx_requires_valid_range(__first, __last); - for ( ; __first != __last; ++__first) + for (; __first != __last; ++__first) if (!(*__first == __value)) { *__result = *__first; @@ -1248,7 +1537,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) typename iterator_traits<_InputIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); - for ( ; __first != __last; ++__first) + for (; __first != __last; ++__first) if (!bool(__pred(*__first))) { *__result = *__first; @@ -1328,35 +1617,114 @@ _GLIBCXX_BEGIN_NAMESPACE(std) } /** - * @if maint - * This is an uglified unique_copy(_InputIterator, _InputIterator, - * _OutputIterator) - * overloaded for forward iterators and output iterator as result. - * @endif + * @brief Remove consecutive duplicate values from a sequence. + * @param first A forward iterator. + * @param last A forward iterator. + * @return An iterator designating the end of the resulting sequence. + * + * Removes all but the first element from each group of consecutive + * values that compare equal. + * unique() is stable, so the relative order of elements that are + * not removed is unchanged. + * Elements between the end of the resulting sequence and @p last + * are still present, but their value is unspecified. */ - template - _OutputIterator - __unique_copy(_ForwardIterator __first, _ForwardIterator __last, - _OutputIterator __result, - forward_iterator_tag, output_iterator_tag) + template + _ForwardIterator + unique(_ForwardIterator __first, _ForwardIterator __last) { - // concept requirements -- taken care of in dispatching function - _ForwardIterator __next = __first; - *__result = *__first; - while (++__next != __last) - if (!(*__first == *__next)) - { - __first = __next; - *++__result = *__first; - } - return ++__result; - } + // concept requirements + __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< + _ForwardIterator>) + __glibcxx_function_requires(_EqualityComparableConcept< + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); - /** - * @if maint - * This is an uglified unique_copy(_InputIterator, _InputIterator, - * _OutputIterator) - * overloaded for input iterators and output iterator as result. + // Skip the beginning, if already unique. + __first = std::adjacent_find(__first, __last); + if (__first == __last) + return __last; + + // Do the real copy work. + _ForwardIterator __dest = __first; + ++__first; + while (++__first != __last) + if (!(*__dest == *__first)) + *++__dest = *__first; + return ++__dest; + } + + /** + * @brief Remove consecutive values from a sequence using a predicate. + * @param first A forward iterator. + * @param last A forward iterator. + * @param binary_pred A binary predicate. + * @return An iterator designating the end of the resulting sequence. + * + * Removes all but the first element from each group of consecutive + * values for which @p binary_pred returns true. + * unique() is stable, so the relative order of elements that are + * not removed is unchanged. + * Elements between the end of the resulting sequence and @p last + * are still present, but their value is unspecified. + */ + template + _ForwardIterator + unique(_ForwardIterator __first, _ForwardIterator __last, + _BinaryPredicate __binary_pred) + { + // concept requirements + __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< + _ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, + typename iterator_traits<_ForwardIterator>::value_type, + typename iterator_traits<_ForwardIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); + + // Skip the beginning, if already unique. + __first = std::adjacent_find(__first, __last, __binary_pred); + if (__first == __last) + return __last; + + // Do the real copy work. + _ForwardIterator __dest = __first; + ++__first; + while (++__first != __last) + if (!bool(__binary_pred(*__dest, *__first))) + *++__dest = *__first; + return ++__dest; + } + + /** + * @if maint + * This is an uglified unique_copy(_InputIterator, _InputIterator, + * _OutputIterator) + * overloaded for forward iterators and output iterator as result. + * @endif + */ + template + _OutputIterator + __unique_copy(_ForwardIterator __first, _ForwardIterator __last, + _OutputIterator __result, + forward_iterator_tag, output_iterator_tag) + { + // concept requirements -- taken care of in dispatching function + _ForwardIterator __next = __first; + *__result = *__first; + while (++__next != __last) + if (!(*__first == *__next)) + { + __first = __next; + *++__result = *__first; + } + return ++__result; + } + + /** + * @if maint + * This is an uglified unique_copy(_InputIterator, _InputIterator, + * _OutputIterator) + * overloaded for input iterators and output iterator as result. * @endif */ template @@ -1569,85 +1937,6 @@ _GLIBCXX_BEGIN_NAMESPACE(std) std::__iterator_category(__result)); } - /** - * @brief Remove consecutive duplicate values from a sequence. - * @param first A forward iterator. - * @param last A forward iterator. - * @return An iterator designating the end of the resulting sequence. - * - * Removes all but the first element from each group of consecutive - * values that compare equal. - * unique() is stable, so the relative order of elements that are - * not removed is unchanged. - * Elements between the end of the resulting sequence and @p last - * are still present, but their value is unspecified. - */ - template - _ForwardIterator - unique(_ForwardIterator __first, _ForwardIterator __last) - { - // concept requirements - __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< - _ForwardIterator>) - __glibcxx_function_requires(_EqualityComparableConcept< - typename iterator_traits<_ForwardIterator>::value_type>) - __glibcxx_requires_valid_range(__first, __last); - - // Skip the beginning, if already unique. - __first = std::adjacent_find(__first, __last); - if (__first == __last) - return __last; - - // Do the real copy work. - _ForwardIterator __dest = __first; - ++__first; - while (++__first != __last) - if (!(*__dest == *__first)) - *++__dest = *__first; - return ++__dest; - } - - /** - * @brief Remove consecutive values from a sequence using a predicate. - * @param first A forward iterator. - * @param last A forward iterator. - * @param binary_pred A binary predicate. - * @return An iterator designating the end of the resulting sequence. - * - * Removes all but the first element from each group of consecutive - * values for which @p binary_pred returns true. - * unique() is stable, so the relative order of elements that are - * not removed is unchanged. - * Elements between the end of the resulting sequence and @p last - * are still present, but their value is unspecified. - */ - template - _ForwardIterator - unique(_ForwardIterator __first, _ForwardIterator __last, - _BinaryPredicate __binary_pred) - { - // concept requirements - __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< - _ForwardIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, - typename iterator_traits<_ForwardIterator>::value_type, - typename iterator_traits<_ForwardIterator>::value_type>) - __glibcxx_requires_valid_range(__first, __last); - - // Skip the beginning, if already unique. - __first = std::adjacent_find(__first, __last, __binary_pred); - if (__first == __last) - return __last; - - // Do the real copy work. - _ForwardIterator __dest = __first; - ++__first; - while (++__first != __last) - if (!bool(__binary_pred(*__dest, *__first))) - *++__dest = *__first; - return ++__dest; - } - /** * @if maint * This is an uglified reverse(_BidirectionalIterator, @@ -1751,7 +2040,6 @@ _GLIBCXX_BEGIN_NAMESPACE(std) return __result; } - /** * @if maint * This is a helper function for the rotate algorithm specialized on RAIs. @@ -1879,7 +2167,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) return; } - const _Distance __d = __gcd(__n, __k); + const _Distance __d = std::__gcd(__n, __k); for (_Distance __i = 0; __i < __d; __i++) { @@ -2180,7 +2468,7 @@ _GLIBCXX_BEGIN_NAMESPACE(std) { _ForwardIterator __result1 = __first; _Pointer __result2 = __buffer; - for ( ; __first != __last ; ++__first) + for (; __first != __last; ++__first) if (__pred(*__first)) { *__result1 = *__first; @@ -2266,281 +2554,42 @@ _GLIBCXX_BEGIN_NAMESPACE(std) /** * @if maint - * This is a helper function... + * This is a helper function for the sort routines. * @endif */ - template - _RandomAccessIterator - __unguarded_partition(_RandomAccessIterator __first, - _RandomAccessIterator __last, _Tp __pivot) + template + void + __heap_select(_RandomAccessIterator __first, + _RandomAccessIterator __middle, + _RandomAccessIterator __last) { - while (true) - { - while (*__first < __pivot) - ++__first; - --__last; - while (__pivot < *__last) - --__last; - if (!(__first < __last)) - return __first; - std::iter_swap(__first, __last); - ++__first; - } - } + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; - /** - * @if maint - * This is a helper function... - * @endif - */ - template - _RandomAccessIterator - __unguarded_partition(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Tp __pivot, _Compare __comp) - { - while (true) - { - while (__comp(*__first, __pivot)) - ++__first; - --__last; - while (__comp(__pivot, *__last)) - --__last; - if (!(__first < __last)) - return __first; - std::iter_swap(__first, __last); - ++__first; - } + std::make_heap(__first, __middle); + for (_RandomAccessIterator __i = __middle; __i < __last; ++__i) + if (*__i < *__first) + std::__pop_heap(__first, __middle, __i, _ValueType(*__i)); } /** * @if maint - * @doctodo - * This controls some aspect of the sort routines. - * @endif - */ - enum { _S_threshold = 16 }; - - /** - * @if maint - * This is a helper function for the sort routine. + * This is a helper function for the sort routines. * @endif */ - template + template void - __unguarded_linear_insert(_RandomAccessIterator __last, _Tp __val) + __heap_select(_RandomAccessIterator __first, + _RandomAccessIterator __middle, + _RandomAccessIterator __last, _Compare __comp) { - _RandomAccessIterator __next = __last; - --__next; - while (__val < *__next) - { - *__last = *__next; - __last = __next; - --__next; - } - *__last = __val; - } - - /** - * @if maint - * This is a helper function for the sort routine. - * @endif - */ - template - void - __unguarded_linear_insert(_RandomAccessIterator __last, _Tp __val, - _Compare __comp) - { - _RandomAccessIterator __next = __last; - --__next; - while (__comp(__val, *__next)) - { - *__last = *__next; - __last = __next; - --__next; - } - *__last = __val; - } - - /** - * @if maint - * This is a helper function for the sort routine. - * @endif - */ - template - void - __insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last) - { - if (__first == __last) - return; - - for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i) - { - typename iterator_traits<_RandomAccessIterator>::value_type - __val = *__i; - if (__val < *__first) - { - std::copy_backward(__first, __i, __i + 1); - *__first = __val; - } - else - std::__unguarded_linear_insert(__i, __val); - } - } - - /** - * @if maint - * This is a helper function for the sort routine. - * @endif - */ - template - void - __insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last, _Compare __comp) - { - if (__first == __last) return; - - for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i) - { - typename iterator_traits<_RandomAccessIterator>::value_type - __val = *__i; - if (__comp(__val, *__first)) - { - std::copy_backward(__first, __i, __i + 1); - *__first = __val; - } - else - std::__unguarded_linear_insert(__i, __val, __comp); - } - } - - /** - * @if maint - * This is a helper function for the sort routine. - * @endif - */ - template - inline void - __unguarded_insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last) - { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - for (_RandomAccessIterator __i = __first; __i != __last; ++__i) - std::__unguarded_linear_insert(__i, _ValueType(*__i)); - } - - /** - * @if maint - * This is a helper function for the sort routine. - * @endif - */ - template - inline void - __unguarded_insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last, _Compare __comp) - { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - for (_RandomAccessIterator __i = __first; __i != __last; ++__i) - std::__unguarded_linear_insert(__i, _ValueType(*__i), __comp); - } - - /** - * @if maint - * This is a helper function for the sort routine. - * @endif - */ - template - void - __final_insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last) - { - if (__last - __first > int(_S_threshold)) - { - std::__insertion_sort(__first, __first + int(_S_threshold)); - std::__unguarded_insertion_sort(__first + int(_S_threshold), __last); - } - else - std::__insertion_sort(__first, __last); - } - - /** - * @if maint - * This is a helper function for the sort routine. - * @endif - */ - template - void - __final_insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last, _Compare __comp) - { - if (__last - __first > int(_S_threshold)) - { - std::__insertion_sort(__first, __first + int(_S_threshold), __comp); - std::__unguarded_insertion_sort(__first + int(_S_threshold), __last, - __comp); - } - else - std::__insertion_sort(__first, __last, __comp); - } - - /** - * @if maint - * This is a helper function for the sort routines. - * @endif - */ - template - void - __heap_select(_RandomAccessIterator __first, - _RandomAccessIterator __middle, - _RandomAccessIterator __last) - { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - std::make_heap(__first, __middle); - for (_RandomAccessIterator __i = __middle; __i < __last; ++__i) - if (*__i < *__first) - std::__pop_heap(__first, __middle, __i, _ValueType(*__i)); - } - - /** - * @if maint - * This is a helper function for the sort routines. - * @endif - */ - template - void - __heap_select(_RandomAccessIterator __first, - _RandomAccessIterator __middle, - _RandomAccessIterator __last, _Compare __comp) - { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - std::make_heap(__first, __middle, __comp); - for (_RandomAccessIterator __i = __middle; __i < __last; ++__i) - if (__comp(*__i, *__first)) - std::__pop_heap(__first, __middle, __i, _ValueType(*__i), __comp); - } - - /** - * @if maint - * This is a helper function for the sort routines. - * @endif - */ - template - inline _Size - __lg(_Size __n) - { - _Size __k; - for (__k = 0; __n != 1; __n >>= 1) - ++__k; - return __k; + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; + + std::make_heap(__first, __middle, __comp); + for (_RandomAccessIterator __i = __middle; __i < __last; ++__i) + if (__comp(*__i, *__first)) + std::__pop_heap(__first, __middle, __i, _ValueType(*__i), __comp); } /** @@ -2756,35 +2805,19 @@ _GLIBCXX_BEGIN_NAMESPACE(std) * This is a helper function for the sort routine. * @endif */ - template + template void - __introsort_loop(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Size __depth_limit) + __unguarded_linear_insert(_RandomAccessIterator __last, _Tp __val) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - while (__last - __first > int(_S_threshold)) + _RandomAccessIterator __next = __last; + --__next; + while (__val < *__next) { - if (__depth_limit == 0) - { - std::partial_sort(__first, __last, __last); - return; - } - --__depth_limit; - _RandomAccessIterator __cut = - std::__unguarded_partition(__first, __last, - _ValueType(std::__median(*__first, - *(__first - + (__last - - __first) - / 2), - *(__last - - 1)))); - std::__introsort_loop(__cut, __last, __depth_limit); - __last = __cut; + *__last = *__next; + __last = __next; + --__next; } + *__last = __val; } /** @@ -2792,1511 +2825,1765 @@ _GLIBCXX_BEGIN_NAMESPACE(std) * This is a helper function for the sort routine. * @endif */ - template + template void - __introsort_loop(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Size __depth_limit, _Compare __comp) + __unguarded_linear_insert(_RandomAccessIterator __last, _Tp __val, + _Compare __comp) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - while (__last - __first > int(_S_threshold)) + _RandomAccessIterator __next = __last; + --__next; + while (__comp(__val, *__next)) { - if (__depth_limit == 0) - { - std::partial_sort(__first, __last, __last, __comp); - return; - } - --__depth_limit; - _RandomAccessIterator __cut = - std::__unguarded_partition(__first, __last, - _ValueType(std::__median(*__first, - *(__first - + (__last - - __first) - / 2), - *(__last - 1), - __comp)), - __comp); - std::__introsort_loop(__cut, __last, __depth_limit, __comp); - __last = __cut; + *__last = *__next; + __last = __next; + --__next; } + *__last = __val; } /** - * @brief Sort the elements of a sequence. - * @param first An iterator. - * @param last Another iterator. - * @return Nothing. - * - * Sorts the elements in the range @p [first,last) in ascending order, - * such that @p *(i+1)<*i is false for each iterator @p i in the range - * @p [first,last-1). - * - * The relative ordering of equivalent elements is not preserved, use - * @p stable_sort() if this is needed. + * @if maint + * This is a helper function for the sort routine. + * @endif */ template - inline void - sort(_RandomAccessIterator __first, _RandomAccessIterator __last) + void + __insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - // concept requirements - __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< - _RandomAccessIterator>) - __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) - __glibcxx_requires_valid_range(__first, __last); + if (__first == __last) + return; - if (__first != __last) + for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i) { - std::__introsort_loop(__first, __last, - std::__lg(__last - __first) * 2); - std::__final_insertion_sort(__first, __last); + typename iterator_traits<_RandomAccessIterator>::value_type + __val = *__i; + if (__val < *__first) + { + std::copy_backward(__first, __i, __i + 1); + *__first = __val; + } + else + std::__unguarded_linear_insert(__i, __val); } } /** - * @brief Sort the elements of a sequence using a predicate for comparison. - * @param first An iterator. - * @param last Another iterator. - * @param comp A comparison functor. - * @return Nothing. - * - * Sorts the elements in the range @p [first,last) in ascending order, - * such that @p comp(*(i+1),*i) is false for every iterator @p i in the - * range @p [first,last-1). - * - * The relative ordering of equivalent elements is not preserved, use - * @p stable_sort() if this is needed. + * @if maint + * This is a helper function for the sort routine. + * @endif */ template - inline void - sort(_RandomAccessIterator __first, _RandomAccessIterator __last, - _Compare __comp) + void + __insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last, _Compare __comp) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - // concept requirements - __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< - _RandomAccessIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, _ValueType, - _ValueType>) - __glibcxx_requires_valid_range(__first, __last); + if (__first == __last) return; - if (__first != __last) + for (_RandomAccessIterator __i = __first + 1; __i != __last; ++__i) { - std::__introsort_loop(__first, __last, - std::__lg(__last - __first) * 2, __comp); - std::__final_insertion_sort(__first, __last, __comp); + typename iterator_traits<_RandomAccessIterator>::value_type + __val = *__i; + if (__comp(__val, *__first)) + { + std::copy_backward(__first, __i, __i + 1); + *__first = __val; + } + else + std::__unguarded_linear_insert(__i, __val, __comp); } } /** - * @brief Finds the first position in which @a val could be inserted - * without changing the ordering. - * @param first An iterator. - * @param last Another iterator. - * @param val The search term. - * @return An iterator pointing to the first element "not less than" @a val, - * or end() if every element is less than @a val. - * @ingroup binarysearch + * @if maint + * This is a helper function for the sort routine. + * @endif */ - template - _ForwardIterator - lower_bound(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val) + template + inline void + __unguarded_insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last) { - typedef typename iterator_traits<_ForwardIterator>::value_type + typedef typename iterator_traits<_RandomAccessIterator>::value_type _ValueType; - typedef typename iterator_traits<_ForwardIterator>::difference_type - _DistanceType; - - // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>) - __glibcxx_requires_partitioned(__first, __last, __val); - - _DistanceType __len = std::distance(__first, __last); - _DistanceType __half; - _ForwardIterator __middle; - while (__len > 0) - { - __half = __len >> 1; - __middle = __first; - std::advance(__middle, __half); - if (*__middle < __val) - { - __first = __middle; - ++__first; - __len = __len - __half - 1; - } - else - __len = __half; - } - return __first; + for (_RandomAccessIterator __i = __first; __i != __last; ++__i) + std::__unguarded_linear_insert(__i, _ValueType(*__i)); } /** - * @brief Finds the first position in which @a val could be inserted - * without changing the ordering. - * @param first An iterator. - * @param last Another iterator. - * @param val The search term. - * @param comp A functor to use for comparisons. - * @return An iterator pointing to the first element "not less than" @a val, - * or end() if every element is less than @a val. - * @ingroup binarysearch - * - * The comparison function should have the same effects on ordering as - * the function used for the initial sort. + * @if maint + * This is a helper function for the sort routine. + * @endif */ - template - _ForwardIterator - lower_bound(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val, _Compare __comp) + template + inline void + __unguarded_insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last, _Compare __comp) { - typedef typename iterator_traits<_ForwardIterator>::value_type + typedef typename iterator_traits<_RandomAccessIterator>::value_type _ValueType; - typedef typename iterator_traits<_ForwardIterator>::difference_type - _DistanceType; - // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _ValueType, _Tp>) - __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); + for (_RandomAccessIterator __i = __first; __i != __last; ++__i) + std::__unguarded_linear_insert(__i, _ValueType(*__i), __comp); + } - _DistanceType __len = std::distance(__first, __last); - _DistanceType __half; - _ForwardIterator __middle; + /** + * @if maint + * @doctodo + * This controls some aspect of the sort routines. + * @endif + */ + enum { _S_threshold = 16 }; - while (__len > 0) + /** + * @if maint + * This is a helper function for the sort routine. + * @endif + */ + template + void + __final_insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last) + { + if (__last - __first > int(_S_threshold)) { - __half = __len >> 1; - __middle = __first; - std::advance(__middle, __half); - if (__comp(*__middle, __val)) - { - __first = __middle; - ++__first; - __len = __len - __half - 1; - } - else - __len = __half; + std::__insertion_sort(__first, __first + int(_S_threshold)); + std::__unguarded_insertion_sort(__first + int(_S_threshold), __last); } - return __first; + else + std::__insertion_sort(__first, __last); } /** - * @brief Finds the last position in which @a val could be inserted - * without changing the ordering. - * @param first An iterator. - * @param last Another iterator. - * @param val The search term. - * @return An iterator pointing to the first element greater than @a val, - * or end() if no elements are greater than @a val. - * @ingroup binarysearch + * @if maint + * This is a helper function for the sort routine. + * @endif */ - template - _ForwardIterator - upper_bound(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val) + template + void + __final_insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last, _Compare __comp) { - typedef typename iterator_traits<_ForwardIterator>::value_type - _ValueType; - typedef typename iterator_traits<_ForwardIterator>::difference_type - _DistanceType; - - // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>) - __glibcxx_requires_partitioned(__first, __last, __val); - - _DistanceType __len = std::distance(__first, __last); - _DistanceType __half; - _ForwardIterator __middle; - - while (__len > 0) + if (__last - __first > int(_S_threshold)) { - __half = __len >> 1; - __middle = __first; - std::advance(__middle, __half); - if (__val < *__middle) - __len = __half; - else - { - __first = __middle; - ++__first; - __len = __len - __half - 1; - } + std::__insertion_sort(__first, __first + int(_S_threshold), __comp); + std::__unguarded_insertion_sort(__first + int(_S_threshold), __last, + __comp); } - return __first; + else + std::__insertion_sort(__first, __last, __comp); } /** - * @brief Finds the last position in which @a val could be inserted - * without changing the ordering. - * @param first An iterator. - * @param last Another iterator. - * @param val The search term. - * @param comp A functor to use for comparisons. - * @return An iterator pointing to the first element greater than @a val, - * or end() if no elements are greater than @a val. - * @ingroup binarysearch - * - * The comparison function should have the same effects on ordering as - * the function used for the initial sort. + * @if maint + * This is a helper function... + * @endif */ - template - _ForwardIterator - upper_bound(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val, _Compare __comp) + template + _RandomAccessIterator + __unguarded_partition(_RandomAccessIterator __first, + _RandomAccessIterator __last, _Tp __pivot) { - typedef typename iterator_traits<_ForwardIterator>::value_type - _ValueType; - typedef typename iterator_traits<_ForwardIterator>::difference_type - _DistanceType; - - // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _Tp, _ValueType>) - __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); - - _DistanceType __len = std::distance(__first, __last); - _DistanceType __half; - _ForwardIterator __middle; - - while (__len > 0) + while (true) { - __half = __len >> 1; - __middle = __first; - std::advance(__middle, __half); - if (__comp(__val, *__middle)) - __len = __half; - else - { - __first = __middle; - ++__first; - __len = __len - __half - 1; - } + while (*__first < __pivot) + ++__first; + --__last; + while (__pivot < *__last) + --__last; + if (!(__first < __last)) + return __first; + std::iter_swap(__first, __last); + ++__first; } - return __first; } /** * @if maint - * This is a helper function for the merge routines. + * This is a helper function... * @endif */ - template - void - __merge_without_buffer(_BidirectionalIterator __first, - _BidirectionalIterator __middle, - _BidirectionalIterator __last, - _Distance __len1, _Distance __len2) + template + _RandomAccessIterator + __unguarded_partition(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Tp __pivot, _Compare __comp) { - if (__len1 == 0 || __len2 == 0) - return; - if (__len1 + __len2 == 2) - { - if (*__middle < *__first) - std::iter_swap(__first, __middle); - return; - } - _BidirectionalIterator __first_cut = __first; - _BidirectionalIterator __second_cut = __middle; - _Distance __len11 = 0; - _Distance __len22 = 0; - if (__len1 > __len2) - { - __len11 = __len1 / 2; - std::advance(__first_cut, __len11); - __second_cut = std::lower_bound(__middle, __last, *__first_cut); - __len22 = std::distance(__middle, __second_cut); - } - else + while (true) { - __len22 = __len2 / 2; - std::advance(__second_cut, __len22); - __first_cut = std::upper_bound(__first, __middle, *__second_cut); - __len11 = std::distance(__first, __first_cut); + while (__comp(*__first, __pivot)) + ++__first; + --__last; + while (__comp(__pivot, *__last)) + --__last; + if (!(__first < __last)) + return __first; + std::iter_swap(__first, __last); + ++__first; } - std::rotate(__first_cut, __middle, __second_cut); - _BidirectionalIterator __new_middle = __first_cut; - std::advance(__new_middle, std::distance(__middle, __second_cut)); - std::__merge_without_buffer(__first, __first_cut, __new_middle, - __len11, __len22); - std::__merge_without_buffer(__new_middle, __second_cut, __last, - __len1 - __len11, __len2 - __len22); } /** * @if maint - * This is a helper function for the merge routines. + * This is a helper function for the sort routine. * @endif */ - template + template void - __merge_without_buffer(_BidirectionalIterator __first, - _BidirectionalIterator __middle, - _BidirectionalIterator __last, - _Distance __len1, _Distance __len2, - _Compare __comp) + __introsort_loop(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Size __depth_limit) { - if (__len1 == 0 || __len2 == 0) - return; - if (__len1 + __len2 == 2) - { - if (__comp(*__middle, *__first)) - std::iter_swap(__first, __middle); - return; - } - _BidirectionalIterator __first_cut = __first; - _BidirectionalIterator __second_cut = __middle; - _Distance __len11 = 0; - _Distance __len22 = 0; - if (__len1 > __len2) - { - __len11 = __len1 / 2; - std::advance(__first_cut, __len11); - __second_cut = std::lower_bound(__middle, __last, *__first_cut, - __comp); - __len22 = std::distance(__middle, __second_cut); - } - else + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; + + while (__last - __first > int(_S_threshold)) { - __len22 = __len2 / 2; - std::advance(__second_cut, __len22); - __first_cut = std::upper_bound(__first, __middle, *__second_cut, - __comp); - __len11 = std::distance(__first, __first_cut); + if (__depth_limit == 0) + { + std::partial_sort(__first, __last, __last); + return; + } + --__depth_limit; + _RandomAccessIterator __cut = + std::__unguarded_partition(__first, __last, + _ValueType(std::__median(*__first, + *(__first + + (__last + - __first) + / 2), + *(__last + - 1)))); + std::__introsort_loop(__cut, __last, __depth_limit); + __last = __cut; } - std::rotate(__first_cut, __middle, __second_cut); - _BidirectionalIterator __new_middle = __first_cut; - std::advance(__new_middle, std::distance(__middle, __second_cut)); - std::__merge_without_buffer(__first, __first_cut, __new_middle, - __len11, __len22, __comp); - std::__merge_without_buffer(__new_middle, __second_cut, __last, - __len1 - __len11, __len2 - __len22, __comp); } /** * @if maint - * This is a helper function for the stable sorting routines. + * This is a helper function for the sort routine. * @endif */ - template + template void - __inplace_stable_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last) + __introsort_loop(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Size __depth_limit, _Compare __comp) { - if (__last - __first < 15) + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; + + while (__last - __first > int(_S_threshold)) { - std::__insertion_sort(__first, __last); - return; + if (__depth_limit == 0) + { + std::partial_sort(__first, __last, __last, __comp); + return; + } + --__depth_limit; + _RandomAccessIterator __cut = + std::__unguarded_partition(__first, __last, + _ValueType(std::__median(*__first, + *(__first + + (__last + - __first) + / 2), + *(__last - 1), + __comp)), + __comp); + std::__introsort_loop(__cut, __last, __depth_limit, __comp); + __last = __cut; } - _RandomAccessIterator __middle = __first + (__last - __first) / 2; - std::__inplace_stable_sort(__first, __middle); - std::__inplace_stable_sort(__middle, __last); - std::__merge_without_buffer(__first, __middle, __last, - __middle - __first, - __last - __middle); } /** * @if maint - * This is a helper function for the stable sorting routines. + * This is a helper function for the sort routines. * @endif */ - template - void - __inplace_stable_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last, _Compare __comp) + template + inline _Size + __lg(_Size __n) { - if (__last - __first < 15) - { - std::__insertion_sort(__first, __last, __comp); - return; - } - _RandomAccessIterator __middle = __first + (__last - __first) / 2; - std::__inplace_stable_sort(__first, __middle, __comp); - std::__inplace_stable_sort(__middle, __last, __comp); - std::__merge_without_buffer(__first, __middle, __last, - __middle - __first, - __last - __middle, - __comp); + _Size __k; + for (__k = 0; __n != 1; __n >>= 1) + ++__k; + return __k; } /** - * @brief Merges two sorted ranges. - * @param first1 An iterator. - * @param first2 Another iterator. - * @param last1 Another iterator. - * @param last2 Another iterator. - * @param result An iterator pointing to the end of the merged range. - * @return An iterator pointing to the first element "not less than" @a val. + * @brief Sort the elements of a sequence. + * @param first An iterator. + * @param last Another iterator. + * @return Nothing. * - * Merges the ranges [first1,last1) and [first2,last2) into the sorted range - * [result, result + (last1-first1) + (last2-first2)). Both input ranges - * must be sorted, and the output range must not overlap with either of - * the input ranges. The sort is @e stable, that is, for equivalent - * elements in the two ranges, elements from the first range will always - * come before elements from the second. + * Sorts the elements in the range @p [first,last) in ascending order, + * such that @p *(i+1)<*i is false for each iterator @p i in the range + * @p [first,last-1). + * + * The relative ordering of equivalent elements is not preserved, use + * @p stable_sort() if this is needed. */ - template - _OutputIterator - merge(_InputIterator1 __first1, _InputIterator1 __last1, - _InputIterator2 __first2, _InputIterator2 __last2, - _OutputIterator __result) + template + inline void + sort(_RandomAccessIterator __first, _RandomAccessIterator __last) { - typedef typename iterator_traits<_InputIterator1>::value_type - _ValueType1; - typedef typename iterator_traits<_InputIterator2>::value_type - _ValueType2; + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; // concept requirements - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) - __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, - _ValueType1>) - __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, - _ValueType2>) - __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>) - __glibcxx_requires_sorted(__first1, __last1); - __glibcxx_requires_sorted(__first2, __last2); + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) + __glibcxx_requires_valid_range(__first, __last); - while (__first1 != __last1 && __first2 != __last2) + if (__first != __last) { - if (*__first2 < *__first1) - { - *__result = *__first2; - ++__first2; - } - else - { - *__result = *__first1; - ++__first1; - } - ++__result; + std::__introsort_loop(__first, __last, + std::__lg(__last - __first) * 2); + std::__final_insertion_sort(__first, __last); } - return std::copy(__first2, __last2, std::copy(__first1, __last1, - __result)); } /** - * @brief Merges two sorted ranges. - * @param first1 An iterator. - * @param first2 Another iterator. - * @param last1 Another iterator. - * @param last2 Another iterator. - * @param result An iterator pointing to the end of the merged range. - * @param comp A functor to use for comparisons. - * @return An iterator pointing to the first element "not less than" @a val. + * @brief Sort the elements of a sequence using a predicate for comparison. + * @param first An iterator. + * @param last Another iterator. + * @param comp A comparison functor. + * @return Nothing. * - * Merges the ranges [first1,last1) and [first2,last2) into the sorted range - * [result, result + (last1-first1) + (last2-first2)). Both input ranges - * must be sorted, and the output range must not overlap with either of - * the input ranges. The sort is @e stable, that is, for equivalent - * elements in the two ranges, elements from the first range will always - * come before elements from the second. + * Sorts the elements in the range @p [first,last) in ascending order, + * such that @p comp(*(i+1),*i) is false for every iterator @p i in the + * range @p [first,last-1). * - * The comparison function should have the same effects on ordering as - * the function used for the initial sort. + * The relative ordering of equivalent elements is not preserved, use + * @p stable_sort() if this is needed. */ - template - _OutputIterator - merge(_InputIterator1 __first1, _InputIterator1 __last1, - _InputIterator2 __first2, _InputIterator2 __last2, - _OutputIterator __result, _Compare __comp) + template + inline void + sort(_RandomAccessIterator __first, _RandomAccessIterator __last, + _Compare __comp) { - typedef typename iterator_traits<_InputIterator1>::value_type - _ValueType1; - typedef typename iterator_traits<_InputIterator2>::value_type - _ValueType2; + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; // concept requirements - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) - __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, - _ValueType1>) - __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, - _ValueType2>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _ValueType2, _ValueType1>) - __glibcxx_requires_sorted_pred(__first1, __last1, __comp); - __glibcxx_requires_sorted_pred(__first2, __last2, __comp); + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, _ValueType, + _ValueType>) + __glibcxx_requires_valid_range(__first, __last); - while (__first1 != __last1 && __first2 != __last2) + if (__first != __last) { - if (__comp(*__first2, *__first1)) - { - *__result = *__first2; - ++__first2; - } - else - { - *__result = *__first1; - ++__first1; - } - ++__result; + std::__introsort_loop(__first, __last, + std::__lg(__last - __first) * 2, __comp); + std::__final_insertion_sort(__first, __last, __comp); } - return std::copy(__first2, __last2, std::copy(__first1, __last1, - __result)); } - template + template void - __merge_sort_loop(_RandomAccessIterator1 __first, - _RandomAccessIterator1 __last, - _RandomAccessIterator2 __result, - _Distance __step_size) + __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth, + _RandomAccessIterator __last, _Size __depth_limit) { - const _Distance __two_step = 2 * __step_size; + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; - while (__last - __first >= __two_step) + while (__last - __first > 3) { - __result = std::merge(__first, __first + __step_size, - __first + __step_size, __first + __two_step, - __result); - __first += __two_step; + if (__depth_limit == 0) + { + std::__heap_select(__first, __nth + 1, __last); + // Place the nth largest element in its final position. + std::iter_swap(__first, __nth); + return; + } + --__depth_limit; + _RandomAccessIterator __cut = + std::__unguarded_partition(__first, __last, + _ValueType(std::__median(*__first, + *(__first + + (__last + - __first) + / 2), + *(__last + - 1)))); + if (__cut <= __nth) + __first = __cut; + else + __last = __cut; } - - __step_size = std::min(_Distance(__last - __first), __step_size); - std::merge(__first, __first + __step_size, __first + __step_size, __last, - __result); + std::__insertion_sort(__first, __last); } - template + template void - __merge_sort_loop(_RandomAccessIterator1 __first, - _RandomAccessIterator1 __last, - _RandomAccessIterator2 __result, _Distance __step_size, - _Compare __comp) + __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth, + _RandomAccessIterator __last, _Size __depth_limit, + _Compare __comp) { - const _Distance __two_step = 2 * __step_size; + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; - while (__last - __first >= __two_step) + while (__last - __first > 3) { - __result = std::merge(__first, __first + __step_size, - __first + __step_size, __first + __two_step, - __result, - __comp); - __first += __two_step; + if (__depth_limit == 0) + { + std::__heap_select(__first, __nth + 1, __last, __comp); + // Place the nth largest element in its final position. + std::iter_swap(__first, __nth); + return; + } + --__depth_limit; + _RandomAccessIterator __cut = + std::__unguarded_partition(__first, __last, + _ValueType(std::__median(*__first, + *(__first + + (__last + - __first) + / 2), + *(__last - 1), + __comp)), + __comp); + if (__cut <= __nth) + __first = __cut; + else + __last = __cut; } - __step_size = std::min(_Distance(__last - __first), __step_size); - - std::merge(__first, __first + __step_size, - __first + __step_size, __last, - __result, - __comp); + std::__insertion_sort(__first, __last, __comp); } - enum { _S_chunk_size = 7 }; - - template - void - __chunk_insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Distance __chunk_size) - { - while (__last - __first >= __chunk_size) - { - std::__insertion_sort(__first, __first + __chunk_size); - __first += __chunk_size; - } - std::__insertion_sort(__first, __last); - } - - template - void - __chunk_insertion_sort(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Distance __chunk_size, _Compare __comp) - { - while (__last - __first >= __chunk_size) - { - std::__insertion_sort(__first, __first + __chunk_size, __comp); - __first += __chunk_size; - } - std::__insertion_sort(__first, __last, __comp); - } - - template - void - __merge_sort_with_buffer(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Pointer __buffer) + /** + * @brief Sort a sequence just enough to find a particular position. + * @param first An iterator. + * @param nth Another iterator. + * @param last Another iterator. + * @return Nothing. + * + * Rearranges the elements in the range @p [first,last) so that @p *nth + * is the same element that would have been in that position had the + * whole sequence been sorted. + * whole sequence been sorted. The elements either side of @p *nth are + * not completely sorted, but for any iterator @i in the range + * @p [first,nth) and any iterator @j in the range @p [nth,last) it + * holds that @p *j<*i is false. + */ + template + inline void + nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, + _RandomAccessIterator __last) { - typedef typename iterator_traits<_RandomAccessIterator>::difference_type - _Distance; + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; - const _Distance __len = __last - __first; - const _Pointer __buffer_last = __buffer + __len; + // concept requirements + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) + __glibcxx_requires_valid_range(__first, __nth); + __glibcxx_requires_valid_range(__nth, __last); - _Distance __step_size = _S_chunk_size; - std::__chunk_insertion_sort(__first, __last, __step_size); + if (__first == __last || __nth == __last) + return; - while (__step_size < __len) - { - std::__merge_sort_loop(__first, __last, __buffer, __step_size); - __step_size *= 2; - std::__merge_sort_loop(__buffer, __buffer_last, __first, __step_size); - __step_size *= 2; - } + std::__introselect(__first, __nth, __last, + std::__lg(__last - __first) * 2); } - template - void - __merge_sort_with_buffer(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Pointer __buffer, _Compare __comp) + /** + * @brief Sort a sequence just enough to find a particular position + * using a predicate for comparison. + * @param first An iterator. + * @param nth Another iterator. + * @param last Another iterator. + * @param comp A comparison functor. + * @return Nothing. + * + * Rearranges the elements in the range @p [first,last) so that @p *nth + * is the same element that would have been in that position had the + * whole sequence been sorted. The elements either side of @p *nth are + * not completely sorted, but for any iterator @i in the range + * @p [first,nth) and any iterator @j in the range @p [nth,last) it + * holds that @p comp(*j,*i) is false. + */ + template + inline void + nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, + _RandomAccessIterator __last, _Compare __comp) { - typedef typename iterator_traits<_RandomAccessIterator>::difference_type - _Distance; + typedef typename iterator_traits<_RandomAccessIterator>::value_type + _ValueType; - const _Distance __len = __last - __first; - const _Pointer __buffer_last = __buffer + __len; + // concept requirements + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _ValueType, _ValueType>) + __glibcxx_requires_valid_range(__first, __nth); + __glibcxx_requires_valid_range(__nth, __last); - _Distance __step_size = _S_chunk_size; - std::__chunk_insertion_sort(__first, __last, __step_size, __comp); + if (__first == __last || __nth == __last) + return; - while (__step_size < __len) - { - std::__merge_sort_loop(__first, __last, __buffer, - __step_size, __comp); - __step_size *= 2; - std::__merge_sort_loop(__buffer, __buffer_last, __first, - __step_size, __comp); - __step_size *= 2; - } + std::__introselect(__first, __nth, __last, + std::__lg(__last - __first) * 2, __comp); } /** - * @if maint - * This is a helper function for the merge routines. - * @endif + * @brief Finds the first position in which @a val could be inserted + * without changing the ordering. + * @param first An iterator. + * @param last Another iterator. + * @param val The search term. + * @return An iterator pointing to the first element "not less than" @a val, + * or end() if every element is less than @a val. + * @ingroup binarysearch */ - template - _BidirectionalIterator3 - __merge_backward(_BidirectionalIterator1 __first1, - _BidirectionalIterator1 __last1, - _BidirectionalIterator2 __first2, - _BidirectionalIterator2 __last2, - _BidirectionalIterator3 __result) + template + _ForwardIterator + lower_bound(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val) { - if (__first1 == __last1) - return std::copy_backward(__first2, __last2, __result); - if (__first2 == __last2) - return std::copy_backward(__first1, __last1, __result); - --__last1; - --__last2; - while (true) + typedef typename iterator_traits<_ForwardIterator>::value_type + _ValueType; + typedef typename iterator_traits<_ForwardIterator>::difference_type + _DistanceType; + + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>) + __glibcxx_requires_partitioned(__first, __last, __val); + + _DistanceType __len = std::distance(__first, __last); + _DistanceType __half; + _ForwardIterator __middle; + + while (__len > 0) { - if (*__last2 < *__last1) + __half = __len >> 1; + __middle = __first; + std::advance(__middle, __half); + if (*__middle < __val) { - *--__result = *__last1; - if (__first1 == __last1) - return std::copy_backward(__first2, ++__last2, __result); - --__last1; + __first = __middle; + ++__first; + __len = __len - __half - 1; } else - { - *--__result = *__last2; - if (__first2 == __last2) - return std::copy_backward(__first1, ++__last1, __result); - --__last2; - } + __len = __half; } + return __first; } /** - * @if maint - * This is a helper function for the merge routines. - * @endif + * @brief Finds the first position in which @a val could be inserted + * without changing the ordering. + * @param first An iterator. + * @param last Another iterator. + * @param val The search term. + * @param comp A functor to use for comparisons. + * @return An iterator pointing to the first element "not less than" @a val, + * or end() if every element is less than @a val. + * @ingroup binarysearch + * + * The comparison function should have the same effects on ordering as + * the function used for the initial sort. */ - template - _BidirectionalIterator3 - __merge_backward(_BidirectionalIterator1 __first1, - _BidirectionalIterator1 __last1, - _BidirectionalIterator2 __first2, - _BidirectionalIterator2 __last2, - _BidirectionalIterator3 __result, - _Compare __comp) + template + _ForwardIterator + lower_bound(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val, _Compare __comp) { - if (__first1 == __last1) - return std::copy_backward(__first2, __last2, __result); - if (__first2 == __last2) - return std::copy_backward(__first1, __last1, __result); - --__last1; - --__last2; - while (true) + typedef typename iterator_traits<_ForwardIterator>::value_type + _ValueType; + typedef typename iterator_traits<_ForwardIterator>::difference_type + _DistanceType; + + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _ValueType, _Tp>) + __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); + + _DistanceType __len = std::distance(__first, __last); + _DistanceType __half; + _ForwardIterator __middle; + + while (__len > 0) { - if (__comp(*__last2, *__last1)) + __half = __len >> 1; + __middle = __first; + std::advance(__middle, __half); + if (__comp(*__middle, __val)) { - *--__result = *__last1; - if (__first1 == __last1) - return std::copy_backward(__first2, ++__last2, __result); - --__last1; + __first = __middle; + ++__first; + __len = __len - __half - 1; } else - { - *--__result = *__last2; - if (__first2 == __last2) - return std::copy_backward(__first1, ++__last1, __result); - --__last2; - } + __len = __half; } + return __first; } /** - * @if maint - * This is a helper function for the merge routines. - * @endif + * @brief Finds the last position in which @a val could be inserted + * without changing the ordering. + * @param first An iterator. + * @param last Another iterator. + * @param val The search term. + * @return An iterator pointing to the first element greater than @a val, + * or end() if no elements are greater than @a val. + * @ingroup binarysearch */ - template - _BidirectionalIterator1 - __rotate_adaptive(_BidirectionalIterator1 __first, - _BidirectionalIterator1 __middle, - _BidirectionalIterator1 __last, - _Distance __len1, _Distance __len2, - _BidirectionalIterator2 __buffer, - _Distance __buffer_size) + template + _ForwardIterator + upper_bound(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val) { - _BidirectionalIterator2 __buffer_end; - if (__len1 > __len2 && __len2 <= __buffer_size) - { - __buffer_end = std::copy(__middle, __last, __buffer); - std::copy_backward(__first, __middle, __last); - return std::copy(__buffer, __buffer_end, __first); - } - else if (__len1 <= __buffer_size) - { - __buffer_end = std::copy(__first, __middle, __buffer); - std::copy(__middle, __last, __first); - return std::copy_backward(__buffer, __buffer_end, __last); - } - else + typedef typename iterator_traits<_ForwardIterator>::value_type + _ValueType; + typedef typename iterator_traits<_ForwardIterator>::difference_type + _DistanceType; + + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>) + __glibcxx_requires_partitioned(__first, __last, __val); + + _DistanceType __len = std::distance(__first, __last); + _DistanceType __half; + _ForwardIterator __middle; + + while (__len > 0) { - std::rotate(__first, __middle, __last); - std::advance(__first, std::distance(__middle, __last)); - return __first; + __half = __len >> 1; + __middle = __first; + std::advance(__middle, __half); + if (__val < *__middle) + __len = __half; + else + { + __first = __middle; + ++__first; + __len = __len - __half - 1; + } } + return __first; } /** - * @if maint - * This is a helper function for the merge routines. - * @endif + * @brief Finds the last position in which @a val could be inserted + * without changing the ordering. + * @param first An iterator. + * @param last Another iterator. + * @param val The search term. + * @param comp A functor to use for comparisons. + * @return An iterator pointing to the first element greater than @a val, + * or end() if no elements are greater than @a val. + * @ingroup binarysearch + * + * The comparison function should have the same effects on ordering as + * the function used for the initial sort. */ - template - void - __merge_adaptive(_BidirectionalIterator __first, - _BidirectionalIterator __middle, - _BidirectionalIterator __last, - _Distance __len1, _Distance __len2, - _Pointer __buffer, _Distance __buffer_size) + template + _ForwardIterator + upper_bound(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val, _Compare __comp) { - if (__len1 <= __len2 && __len1 <= __buffer_size) - { - _Pointer __buffer_end = std::copy(__first, __middle, __buffer); - std::merge(__buffer, __buffer_end, __middle, __last, __first); - } - else if (__len2 <= __buffer_size) - { - _Pointer __buffer_end = std::copy(__middle, __last, __buffer); - std::__merge_backward(__first, __middle, __buffer, - __buffer_end, __last); - } - else + typedef typename iterator_traits<_ForwardIterator>::value_type + _ValueType; + typedef typename iterator_traits<_ForwardIterator>::difference_type + _DistanceType; + + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _Tp, _ValueType>) + __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); + + _DistanceType __len = std::distance(__first, __last); + _DistanceType __half; + _ForwardIterator __middle; + + while (__len > 0) { - _BidirectionalIterator __first_cut = __first; - _BidirectionalIterator __second_cut = __middle; - _Distance __len11 = 0; - _Distance __len22 = 0; - if (__len1 > __len2) - { - __len11 = __len1 / 2; - std::advance(__first_cut, __len11); - __second_cut = std::lower_bound(__middle, __last, - *__first_cut); - __len22 = std::distance(__middle, __second_cut); - } + __half = __len >> 1; + __middle = __first; + std::advance(__middle, __half); + if (__comp(__val, *__middle)) + __len = __half; else { - __len22 = __len2 / 2; - std::advance(__second_cut, __len22); - __first_cut = std::upper_bound(__first, __middle, - *__second_cut); - __len11 = std::distance(__first, __first_cut); + __first = __middle; + ++__first; + __len = __len - __half - 1; } - _BidirectionalIterator __new_middle = - std::__rotate_adaptive(__first_cut, __middle, __second_cut, - __len1 - __len11, __len22, __buffer, - __buffer_size); - std::__merge_adaptive(__first, __first_cut, __new_middle, __len11, - __len22, __buffer, __buffer_size); - std::__merge_adaptive(__new_middle, __second_cut, __last, - __len1 - __len11, - __len2 - __len22, __buffer, __buffer_size); } + return __first; } /** - * @if maint - * This is a helper function for the merge routines. - * @endif + * @brief Finds the largest subrange in which @a val could be inserted + * at any place in it without changing the ordering. + * @param first An iterator. + * @param last Another iterator. + * @param val The search term. + * @return An pair of iterators defining the subrange. + * @ingroup binarysearch + * + * This is equivalent to + * @code + * std::make_pair(lower_bound(first, last, val), + * upper_bound(first, last, val)) + * @endcode + * but does not actually call those functions. */ - template - void - __merge_adaptive(_BidirectionalIterator __first, - _BidirectionalIterator __middle, - _BidirectionalIterator __last, - _Distance __len1, _Distance __len2, - _Pointer __buffer, _Distance __buffer_size, - _Compare __comp) + template + pair<_ForwardIterator, _ForwardIterator> + equal_range(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val) { - if (__len1 <= __len2 && __len1 <= __buffer_size) - { - _Pointer __buffer_end = std::copy(__first, __middle, __buffer); - std::merge(__buffer, __buffer_end, __middle, __last, __first, __comp); - } - else if (__len2 <= __buffer_size) - { - _Pointer __buffer_end = std::copy(__middle, __last, __buffer); - std::__merge_backward(__first, __middle, __buffer, __buffer_end, - __last, __comp); - } - else + typedef typename iterator_traits<_ForwardIterator>::value_type + _ValueType; + typedef typename iterator_traits<_ForwardIterator>::difference_type + _DistanceType; + + // concept requirements + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>) + __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>) + __glibcxx_requires_partitioned(__first, __last, __val); + + _DistanceType __len = std::distance(__first, __last); + _DistanceType __half; + _ForwardIterator __middle, __left, __right; + + while (__len > 0) { - _BidirectionalIterator __first_cut = __first; - _BidirectionalIterator __second_cut = __middle; - _Distance __len11 = 0; - _Distance __len22 = 0; - if (__len1 > __len2) + __half = __len >> 1; + __middle = __first; + std::advance(__middle, __half); + if (*__middle < __val) { - __len11 = __len1 / 2; - std::advance(__first_cut, __len11); - __second_cut = std::lower_bound(__middle, __last, *__first_cut, - __comp); - __len22 = std::distance(__middle, __second_cut); + __first = __middle; + ++__first; + __len = __len - __half - 1; } + else if (__val < *__middle) + __len = __half; else { - __len22 = __len2 / 2; - std::advance(__second_cut, __len22); - __first_cut = std::upper_bound(__first, __middle, *__second_cut, - __comp); - __len11 = std::distance(__first, __first_cut); + __left = std::lower_bound(__first, __middle, __val); + std::advance(__first, __len); + __right = std::upper_bound(++__middle, __first, __val); + return pair<_ForwardIterator, _ForwardIterator>(__left, __right); } - _BidirectionalIterator __new_middle = - std::__rotate_adaptive(__first_cut, __middle, __second_cut, - __len1 - __len11, __len22, __buffer, - __buffer_size); - std::__merge_adaptive(__first, __first_cut, __new_middle, __len11, - __len22, __buffer, __buffer_size, __comp); - std::__merge_adaptive(__new_middle, __second_cut, __last, - __len1 - __len11, - __len2 - __len22, __buffer, - __buffer_size, __comp); } + return pair<_ForwardIterator, _ForwardIterator>(__first, __first); } /** - * @brief Merges two sorted ranges in place. + * @brief Finds the largest subrange in which @a val could be inserted + * at any place in it without changing the ordering. * @param first An iterator. - * @param middle Another iterator. * @param last Another iterator. - * @return Nothing. - * - * Merges two sorted and consecutive ranges, [first,middle) and - * [middle,last), and puts the result in [first,last). The output will - * be sorted. The sort is @e stable, that is, for equivalent - * elements in the two ranges, elements from the first range will always - * come before elements from the second. + * @param val The search term. + * @param comp A functor to use for comparisons. + * @return An pair of iterators defining the subrange. + * @ingroup binarysearch * - * If enough additional memory is available, this takes (last-first)-1 - * comparisons. Otherwise an NlogN algorithm is used, where N is - * distance(first,last). + * This is equivalent to + * @code + * std::make_pair(lower_bound(first, last, val, comp), + * upper_bound(first, last, val, comp)) + * @endcode + * but does not actually call those functions. */ - template - void - inplace_merge(_BidirectionalIterator __first, - _BidirectionalIterator __middle, - _BidirectionalIterator __last) + template + pair<_ForwardIterator, _ForwardIterator> + equal_range(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val, + _Compare __comp) { - typedef typename iterator_traits<_BidirectionalIterator>::value_type - _ValueType; - typedef typename iterator_traits<_BidirectionalIterator>::difference_type - _DistanceType; + typedef typename iterator_traits<_ForwardIterator>::value_type + _ValueType; + typedef typename iterator_traits<_ForwardIterator>::difference_type + _DistanceType; // concept requirements - __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept< - _BidirectionalIterator>) - __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) - __glibcxx_requires_sorted(__first, __middle); - __glibcxx_requires_sorted(__middle, __last); - - if (__first == __middle || __middle == __last) - return; + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _ValueType, _Tp>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _Tp, _ValueType>) + __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); - _DistanceType __len1 = std::distance(__first, __middle); - _DistanceType __len2 = std::distance(__middle, __last); + _DistanceType __len = std::distance(__first, __last); + _DistanceType __half; + _ForwardIterator __middle, __left, __right; - _Temporary_buffer<_BidirectionalIterator, _ValueType> __buf(__first, - __last); - if (__buf.begin() == 0) - std::__merge_without_buffer(__first, __middle, __last, __len1, __len2); - else - std::__merge_adaptive(__first, __middle, __last, __len1, __len2, - __buf.begin(), _DistanceType(__buf.size())); + while (__len > 0) + { + __half = __len >> 1; + __middle = __first; + std::advance(__middle, __half); + if (__comp(*__middle, __val)) + { + __first = __middle; + ++__first; + __len = __len - __half - 1; + } + else if (__comp(__val, *__middle)) + __len = __half; + else + { + __left = std::lower_bound(__first, __middle, __val, __comp); + std::advance(__first, __len); + __right = std::upper_bound(++__middle, __first, __val, __comp); + return pair<_ForwardIterator, _ForwardIterator>(__left, __right); + } + } + return pair<_ForwardIterator, _ForwardIterator>(__first, __first); } /** - * @brief Merges two sorted ranges in place. + * @brief Determines whether an element exists in a range. * @param first An iterator. - * @param middle Another iterator. * @param last Another iterator. - * @param comp A functor to use for comparisons. - * @return Nothing. - * - * Merges two sorted and consecutive ranges, [first,middle) and - * [middle,last), and puts the result in [first,last). The output will - * be sorted. The sort is @e stable, that is, for equivalent - * elements in the two ranges, elements from the first range will always - * come before elements from the second. - * - * If enough additional memory is available, this takes (last-first)-1 - * comparisons. Otherwise an NlogN algorithm is used, where N is - * distance(first,last). + * @param val The search term. + * @return True if @a val (or its equivelent) is in [@a first,@a last ]. + * @ingroup binarysearch * - * The comparison function should have the same effects on ordering as - * the function used for the initial sort. + * Note that this does not actually return an iterator to @a val. For + * that, use std::find or a container's specialized find member functions. */ - template - void - inplace_merge(_BidirectionalIterator __first, - _BidirectionalIterator __middle, - _BidirectionalIterator __last, - _Compare __comp) + template + bool + binary_search(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val) { - typedef typename iterator_traits<_BidirectionalIterator>::value_type - _ValueType; - typedef typename iterator_traits<_BidirectionalIterator>::difference_type - _DistanceType; + typedef typename iterator_traits<_ForwardIterator>::value_type + _ValueType; // concept requirements - __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept< - _BidirectionalIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _ValueType, _ValueType>) - __glibcxx_requires_sorted_pred(__first, __middle, __comp); - __glibcxx_requires_sorted_pred(__middle, __last, __comp); - - if (__first == __middle || __middle == __last) - return; - - const _DistanceType __len1 = std::distance(__first, __middle); - const _DistanceType __len2 = std::distance(__middle, __last); - - _Temporary_buffer<_BidirectionalIterator, _ValueType> __buf(__first, - __last); - if (__buf.begin() == 0) - std::__merge_without_buffer(__first, __middle, __last, __len1, - __len2, __comp); - else - std::__merge_adaptive(__first, __middle, __last, __len1, __len2, - __buf.begin(), _DistanceType(__buf.size()), - __comp); - } - - template - void - __stable_sort_adaptive(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Pointer __buffer, _Distance __buffer_size) - { - const _Distance __len = (__last - __first + 1) / 2; - const _RandomAccessIterator __middle = __first + __len; - if (__len > __buffer_size) - { - std::__stable_sort_adaptive(__first, __middle, - __buffer, __buffer_size); - std::__stable_sort_adaptive(__middle, __last, - __buffer, __buffer_size); - } - else - { - std::__merge_sort_with_buffer(__first, __middle, __buffer); - std::__merge_sort_with_buffer(__middle, __last, __buffer); - } - std::__merge_adaptive(__first, __middle, __last, - _Distance(__middle - __first), - _Distance(__last - __middle), - __buffer, __buffer_size); - } + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>) + __glibcxx_requires_partitioned(__first, __last, __val); - template - void - __stable_sort_adaptive(_RandomAccessIterator __first, - _RandomAccessIterator __last, - _Pointer __buffer, _Distance __buffer_size, - _Compare __comp) - { - const _Distance __len = (__last - __first + 1) / 2; - const _RandomAccessIterator __middle = __first + __len; - if (__len > __buffer_size) - { - std::__stable_sort_adaptive(__first, __middle, __buffer, - __buffer_size, __comp); - std::__stable_sort_adaptive(__middle, __last, __buffer, - __buffer_size, __comp); - } - else - { - std::__merge_sort_with_buffer(__first, __middle, __buffer, __comp); - std::__merge_sort_with_buffer(__middle, __last, __buffer, __comp); - } - std::__merge_adaptive(__first, __middle, __last, - _Distance(__middle - __first), - _Distance(__last - __middle), - __buffer, __buffer_size, - __comp); + _ForwardIterator __i = std::lower_bound(__first, __last, __val); + return __i != __last && !(__val < *__i); } /** - * @brief Sort the elements of a sequence, preserving the relative order - * of equivalent elements. + * @brief Determines whether an element exists in a range. * @param first An iterator. * @param last Another iterator. - * @return Nothing. + * @param val The search term. + * @param comp A functor to use for comparisons. + * @return True if @a val (or its equivelent) is in [@a first,@a last ]. + * @ingroup binarysearch * - * Sorts the elements in the range @p [first,last) in ascending order, - * such that @p *(i+1)<*i is false for each iterator @p i in the range - * @p [first,last-1). + * Note that this does not actually return an iterator to @a val. For + * that, use std::find or a container's specialized find member functions. * - * The relative ordering of equivalent elements is preserved, so any two - * elements @p x and @p y in the range @p [first,last) such that - * @p x - inline void - stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last) + template + bool + binary_search(_ForwardIterator __first, _ForwardIterator __last, + const _Tp& __val, _Compare __comp) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type + typedef typename iterator_traits<_ForwardIterator>::value_type _ValueType; - typedef typename iterator_traits<_RandomAccessIterator>::difference_type - _DistanceType; // concept requirements - __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< - _RandomAccessIterator>) - __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) - __glibcxx_requires_valid_range(__first, __last); + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _Tp, _ValueType>) + __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); - _Temporary_buffer<_RandomAccessIterator, _ValueType> __buf(__first, - __last); - if (__buf.begin() == 0) - std::__inplace_stable_sort(__first, __last); - else - std::__stable_sort_adaptive(__first, __last, __buf.begin(), - _DistanceType(__buf.size())); + _ForwardIterator __i = std::lower_bound(__first, __last, __val, __comp); + return __i != __last && !bool(__comp(__val, *__i)); } /** - * @brief Sort the elements of a sequence using a predicate for comparison, - * preserving the relative order of equivalent elements. - * @param first An iterator. - * @param last Another iterator. - * @param comp A comparison functor. - * @return Nothing. - * - * Sorts the elements in the range @p [first,last) in ascending order, - * such that @p comp(*(i+1),*i) is false for each iterator @p i in the - * range @p [first,last-1). + * @brief Merges two sorted ranges. + * @param first1 An iterator. + * @param first2 Another iterator. + * @param last1 Another iterator. + * @param last2 Another iterator. + * @param result An iterator pointing to the end of the merged range. + * @return An iterator pointing to the first element "not less than" @a val. * - * The relative ordering of equivalent elements is preserved, so any two - * elements @p x and @p y in the range @p [first,last) such that - * @p comp(x,y) is false and @p comp(y,x) is false will have the same - * relative ordering after calling @p stable_sort(). + * Merges the ranges [first1,last1) and [first2,last2) into the sorted range + * [result, result + (last1-first1) + (last2-first2)). Both input ranges + * must be sorted, and the output range must not overlap with either of + * the input ranges. The sort is @e stable, that is, for equivalent + * elements in the two ranges, elements from the first range will always + * come before elements from the second. */ - template - inline void - stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, - _Compare __comp) + template + _OutputIterator + merge(_InputIterator1 __first1, _InputIterator1 __last1, + _InputIterator2 __first2, _InputIterator2 __last2, + _OutputIterator __result) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - typedef typename iterator_traits<_RandomAccessIterator>::difference_type - _DistanceType; + typedef typename iterator_traits<_InputIterator1>::value_type + _ValueType1; + typedef typename iterator_traits<_InputIterator2>::value_type + _ValueType2; // concept requirements - __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< - _RandomAccessIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _ValueType, - _ValueType>) - __glibcxx_requires_valid_range(__first, __last); - - _Temporary_buffer<_RandomAccessIterator, _ValueType> __buf(__first, - __last); - if (__buf.begin() == 0) - std::__inplace_stable_sort(__first, __last, __comp); - else - std::__stable_sort_adaptive(__first, __last, __buf.begin(), - _DistanceType(__buf.size()), __comp); - } - - - template - void - __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth, - _RandomAccessIterator __last, _Size __depth_limit) - { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + _ValueType1>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + _ValueType2>) + __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>) + __glibcxx_requires_sorted(__first1, __last1); + __glibcxx_requires_sorted(__first2, __last2); - while (__last - __first > 3) + while (__first1 != __last1 && __first2 != __last2) { - if (__depth_limit == 0) + if (*__first2 < *__first1) { - std::__heap_select(__first, __nth + 1, __last); - // Place the nth largest element in its final position. - std::iter_swap(__first, __nth); - return; + *__result = *__first2; + ++__first2; } - --__depth_limit; - _RandomAccessIterator __cut = - std::__unguarded_partition(__first, __last, - _ValueType(std::__median(*__first, - *(__first - + (__last - - __first) - / 2), - *(__last - - 1)))); - if (__cut <= __nth) - __first = __cut; else - __last = __cut; + { + *__result = *__first1; + ++__first1; + } + ++__result; } - std::__insertion_sort(__first, __last); + return std::copy(__first2, __last2, std::copy(__first1, __last1, + __result)); } - template - void - __introselect(_RandomAccessIterator __first, _RandomAccessIterator __nth, - _RandomAccessIterator __last, _Size __depth_limit, - _Compare __comp) + /** + * @brief Merges two sorted ranges. + * @param first1 An iterator. + * @param first2 Another iterator. + * @param last1 Another iterator. + * @param last2 Another iterator. + * @param result An iterator pointing to the end of the merged range. + * @param comp A functor to use for comparisons. + * @return An iterator pointing to the first element "not less than" @a val. + * + * Merges the ranges [first1,last1) and [first2,last2) into the sorted range + * [result, result + (last1-first1) + (last2-first2)). Both input ranges + * must be sorted, and the output range must not overlap with either of + * the input ranges. The sort is @e stable, that is, for equivalent + * elements in the two ranges, elements from the first range will always + * come before elements from the second. + * + * The comparison function should have the same effects on ordering as + * the function used for the initial sort. + */ + template + _OutputIterator + merge(_InputIterator1 __first1, _InputIterator1 __last1, + _InputIterator2 __first2, _InputIterator2 __last2, + _OutputIterator __result, _Compare __comp) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; + typedef typename iterator_traits<_InputIterator1>::value_type + _ValueType1; + typedef typename iterator_traits<_InputIterator2>::value_type + _ValueType2; - while (__last - __first > 3) + // concept requirements + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) + __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + _ValueType1>) + __glibcxx_function_requires(_OutputIteratorConcept<_OutputIterator, + _ValueType2>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _ValueType2, _ValueType1>) + __glibcxx_requires_sorted_pred(__first1, __last1, __comp); + __glibcxx_requires_sorted_pred(__first2, __last2, __comp); + + while (__first1 != __last1 && __first2 != __last2) { - if (__depth_limit == 0) + if (__comp(*__first2, *__first1)) { - std::__heap_select(__first, __nth + 1, __last, __comp); - // Place the nth largest element in its final position. - std::iter_swap(__first, __nth); - return; + *__result = *__first2; + ++__first2; } - --__depth_limit; - _RandomAccessIterator __cut = - std::__unguarded_partition(__first, __last, - _ValueType(std::__median(*__first, - *(__first - + (__last - - __first) - / 2), - *(__last - 1), - __comp)), - __comp); - if (__cut <= __nth) - __first = __cut; else - __last = __cut; + { + *__result = *__first1; + ++__first1; + } + ++__result; } - std::__insertion_sort(__first, __last, __comp); + return std::copy(__first2, __last2, std::copy(__first1, __last1, + __result)); } /** - * @brief Sort a sequence just enough to find a particular position. - * @param first An iterator. - * @param nth Another iterator. - * @param last Another iterator. - * @return Nothing. - * - * Rearranges the elements in the range @p [first,last) so that @p *nth - * is the same element that would have been in that position had the - * whole sequence been sorted. - * whole sequence been sorted. The elements either side of @p *nth are - * not completely sorted, but for any iterator @i in the range - * @p [first,nth) and any iterator @j in the range @p [nth,last) it - * holds that @p *j<*i is false. + * @if maint + * This is a helper function for the merge routines. + * @endif */ - template - inline void - nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, - _RandomAccessIterator __last) + template + _BidirectionalIterator3 + __merge_backward(_BidirectionalIterator1 __first1, + _BidirectionalIterator1 __last1, + _BidirectionalIterator2 __first2, + _BidirectionalIterator2 __last2, + _BidirectionalIterator3 __result) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; - - // concept requirements - __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< - _RandomAccessIterator>) - __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) - __glibcxx_requires_valid_range(__first, __nth); - __glibcxx_requires_valid_range(__nth, __last); - - if (__first == __last || __nth == __last) - return; - - std::__introselect(__first, __nth, __last, - std::__lg(__last - __first) * 2); + if (__first1 == __last1) + return std::copy_backward(__first2, __last2, __result); + if (__first2 == __last2) + return std::copy_backward(__first1, __last1, __result); + --__last1; + --__last2; + while (true) + { + if (*__last2 < *__last1) + { + *--__result = *__last1; + if (__first1 == __last1) + return std::copy_backward(__first2, ++__last2, __result); + --__last1; + } + else + { + *--__result = *__last2; + if (__first2 == __last2) + return std::copy_backward(__first1, ++__last1, __result); + --__last2; + } + } } /** - * @brief Sort a sequence just enough to find a particular position - * using a predicate for comparison. + * @if maint + * This is a helper function for the merge routines. + * @endif + */ + template + _BidirectionalIterator3 + __merge_backward(_BidirectionalIterator1 __first1, + _BidirectionalIterator1 __last1, + _BidirectionalIterator2 __first2, + _BidirectionalIterator2 __last2, + _BidirectionalIterator3 __result, + _Compare __comp) + { + if (__first1 == __last1) + return std::copy_backward(__first2, __last2, __result); + if (__first2 == __last2) + return std::copy_backward(__first1, __last1, __result); + --__last1; + --__last2; + while (true) + { + if (__comp(*__last2, *__last1)) + { + *--__result = *__last1; + if (__first1 == __last1) + return std::copy_backward(__first2, ++__last2, __result); + --__last1; + } + else + { + *--__result = *__last2; + if (__first2 == __last2) + return std::copy_backward(__first1, ++__last1, __result); + --__last2; + } + } + } + + /** + * @if maint + * This is a helper function for the merge routines. + * @endif + */ + template + _BidirectionalIterator1 + __rotate_adaptive(_BidirectionalIterator1 __first, + _BidirectionalIterator1 __middle, + _BidirectionalIterator1 __last, + _Distance __len1, _Distance __len2, + _BidirectionalIterator2 __buffer, + _Distance __buffer_size) + { + _BidirectionalIterator2 __buffer_end; + if (__len1 > __len2 && __len2 <= __buffer_size) + { + __buffer_end = std::copy(__middle, __last, __buffer); + std::copy_backward(__first, __middle, __last); + return std::copy(__buffer, __buffer_end, __first); + } + else if (__len1 <= __buffer_size) + { + __buffer_end = std::copy(__first, __middle, __buffer); + std::copy(__middle, __last, __first); + return std::copy_backward(__buffer, __buffer_end, __last); + } + else + { + std::rotate(__first, __middle, __last); + std::advance(__first, std::distance(__middle, __last)); + return __first; + } + } + + /** + * @if maint + * This is a helper function for the merge routines. + * @endif + */ + template + void + __merge_adaptive(_BidirectionalIterator __first, + _BidirectionalIterator __middle, + _BidirectionalIterator __last, + _Distance __len1, _Distance __len2, + _Pointer __buffer, _Distance __buffer_size) + { + if (__len1 <= __len2 && __len1 <= __buffer_size) + { + _Pointer __buffer_end = std::copy(__first, __middle, __buffer); + std::merge(__buffer, __buffer_end, __middle, __last, __first); + } + else if (__len2 <= __buffer_size) + { + _Pointer __buffer_end = std::copy(__middle, __last, __buffer); + std::__merge_backward(__first, __middle, __buffer, + __buffer_end, __last); + } + else + { + _BidirectionalIterator __first_cut = __first; + _BidirectionalIterator __second_cut = __middle; + _Distance __len11 = 0; + _Distance __len22 = 0; + if (__len1 > __len2) + { + __len11 = __len1 / 2; + std::advance(__first_cut, __len11); + __second_cut = std::lower_bound(__middle, __last, + *__first_cut); + __len22 = std::distance(__middle, __second_cut); + } + else + { + __len22 = __len2 / 2; + std::advance(__second_cut, __len22); + __first_cut = std::upper_bound(__first, __middle, + *__second_cut); + __len11 = std::distance(__first, __first_cut); + } + _BidirectionalIterator __new_middle = + std::__rotate_adaptive(__first_cut, __middle, __second_cut, + __len1 - __len11, __len22, __buffer, + __buffer_size); + std::__merge_adaptive(__first, __first_cut, __new_middle, __len11, + __len22, __buffer, __buffer_size); + std::__merge_adaptive(__new_middle, __second_cut, __last, + __len1 - __len11, + __len2 - __len22, __buffer, __buffer_size); + } + } + + /** + * @if maint + * This is a helper function for the merge routines. + * @endif + */ + template + void + __merge_adaptive(_BidirectionalIterator __first, + _BidirectionalIterator __middle, + _BidirectionalIterator __last, + _Distance __len1, _Distance __len2, + _Pointer __buffer, _Distance __buffer_size, + _Compare __comp) + { + if (__len1 <= __len2 && __len1 <= __buffer_size) + { + _Pointer __buffer_end = std::copy(__first, __middle, __buffer); + std::merge(__buffer, __buffer_end, __middle, __last, __first, __comp); + } + else if (__len2 <= __buffer_size) + { + _Pointer __buffer_end = std::copy(__middle, __last, __buffer); + std::__merge_backward(__first, __middle, __buffer, __buffer_end, + __last, __comp); + } + else + { + _BidirectionalIterator __first_cut = __first; + _BidirectionalIterator __second_cut = __middle; + _Distance __len11 = 0; + _Distance __len22 = 0; + if (__len1 > __len2) + { + __len11 = __len1 / 2; + std::advance(__first_cut, __len11); + __second_cut = std::lower_bound(__middle, __last, *__first_cut, + __comp); + __len22 = std::distance(__middle, __second_cut); + } + else + { + __len22 = __len2 / 2; + std::advance(__second_cut, __len22); + __first_cut = std::upper_bound(__first, __middle, *__second_cut, + __comp); + __len11 = std::distance(__first, __first_cut); + } + _BidirectionalIterator __new_middle = + std::__rotate_adaptive(__first_cut, __middle, __second_cut, + __len1 - __len11, __len22, __buffer, + __buffer_size); + std::__merge_adaptive(__first, __first_cut, __new_middle, __len11, + __len22, __buffer, __buffer_size, __comp); + std::__merge_adaptive(__new_middle, __second_cut, __last, + __len1 - __len11, + __len2 - __len22, __buffer, + __buffer_size, __comp); + } + } + + /** + * @if maint + * This is a helper function for the merge routines. + * @endif + */ + template + void + __merge_without_buffer(_BidirectionalIterator __first, + _BidirectionalIterator __middle, + _BidirectionalIterator __last, + _Distance __len1, _Distance __len2) + { + if (__len1 == 0 || __len2 == 0) + return; + if (__len1 + __len2 == 2) + { + if (*__middle < *__first) + std::iter_swap(__first, __middle); + return; + } + _BidirectionalIterator __first_cut = __first; + _BidirectionalIterator __second_cut = __middle; + _Distance __len11 = 0; + _Distance __len22 = 0; + if (__len1 > __len2) + { + __len11 = __len1 / 2; + std::advance(__first_cut, __len11); + __second_cut = std::lower_bound(__middle, __last, *__first_cut); + __len22 = std::distance(__middle, __second_cut); + } + else + { + __len22 = __len2 / 2; + std::advance(__second_cut, __len22); + __first_cut = std::upper_bound(__first, __middle, *__second_cut); + __len11 = std::distance(__first, __first_cut); + } + std::rotate(__first_cut, __middle, __second_cut); + _BidirectionalIterator __new_middle = __first_cut; + std::advance(__new_middle, std::distance(__middle, __second_cut)); + std::__merge_without_buffer(__first, __first_cut, __new_middle, + __len11, __len22); + std::__merge_without_buffer(__new_middle, __second_cut, __last, + __len1 - __len11, __len2 - __len22); + } + + /** + * @if maint + * This is a helper function for the merge routines. + * @endif + */ + template + void + __merge_without_buffer(_BidirectionalIterator __first, + _BidirectionalIterator __middle, + _BidirectionalIterator __last, + _Distance __len1, _Distance __len2, + _Compare __comp) + { + if (__len1 == 0 || __len2 == 0) + return; + if (__len1 + __len2 == 2) + { + if (__comp(*__middle, *__first)) + std::iter_swap(__first, __middle); + return; + } + _BidirectionalIterator __first_cut = __first; + _BidirectionalIterator __second_cut = __middle; + _Distance __len11 = 0; + _Distance __len22 = 0; + if (__len1 > __len2) + { + __len11 = __len1 / 2; + std::advance(__first_cut, __len11); + __second_cut = std::lower_bound(__middle, __last, *__first_cut, + __comp); + __len22 = std::distance(__middle, __second_cut); + } + else + { + __len22 = __len2 / 2; + std::advance(__second_cut, __len22); + __first_cut = std::upper_bound(__first, __middle, *__second_cut, + __comp); + __len11 = std::distance(__first, __first_cut); + } + std::rotate(__first_cut, __middle, __second_cut); + _BidirectionalIterator __new_middle = __first_cut; + std::advance(__new_middle, std::distance(__middle, __second_cut)); + std::__merge_without_buffer(__first, __first_cut, __new_middle, + __len11, __len22, __comp); + std::__merge_without_buffer(__new_middle, __second_cut, __last, + __len1 - __len11, __len2 - __len22, __comp); + } + + /** + * @brief Merges two sorted ranges in place. * @param first An iterator. - * @param nth Another iterator. + * @param middle Another iterator. * @param last Another iterator. - * @param comp A comparison functor. * @return Nothing. * - * Rearranges the elements in the range @p [first,last) so that @p *nth - * is the same element that would have been in that position had the - * whole sequence been sorted. The elements either side of @p *nth are - * not completely sorted, but for any iterator @i in the range - * @p [first,nth) and any iterator @j in the range @p [nth,last) it - * holds that @p comp(*j,*i) is false. + * Merges two sorted and consecutive ranges, [first,middle) and + * [middle,last), and puts the result in [first,last). The output will + * be sorted. The sort is @e stable, that is, for equivalent + * elements in the two ranges, elements from the first range will always + * come before elements from the second. + * + * If enough additional memory is available, this takes (last-first)-1 + * comparisons. Otherwise an NlogN algorithm is used, where N is + * distance(first,last). */ - template - inline void - nth_element(_RandomAccessIterator __first, _RandomAccessIterator __nth, - _RandomAccessIterator __last, _Compare __comp) + template + void + inplace_merge(_BidirectionalIterator __first, + _BidirectionalIterator __middle, + _BidirectionalIterator __last) { - typedef typename iterator_traits<_RandomAccessIterator>::value_type - _ValueType; + typedef typename iterator_traits<_BidirectionalIterator>::value_type + _ValueType; + typedef typename iterator_traits<_BidirectionalIterator>::difference_type + _DistanceType; + + // concept requirements + __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept< + _BidirectionalIterator>) + __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) + __glibcxx_requires_sorted(__first, __middle); + __glibcxx_requires_sorted(__middle, __last); + + if (__first == __middle || __middle == __last) + return; + + _DistanceType __len1 = std::distance(__first, __middle); + _DistanceType __len2 = std::distance(__middle, __last); + + _Temporary_buffer<_BidirectionalIterator, _ValueType> __buf(__first, + __last); + if (__buf.begin() == 0) + std::__merge_without_buffer(__first, __middle, __last, __len1, __len2); + else + std::__merge_adaptive(__first, __middle, __last, __len1, __len2, + __buf.begin(), _DistanceType(__buf.size())); + } + + /** + * @brief Merges two sorted ranges in place. + * @param first An iterator. + * @param middle Another iterator. + * @param last Another iterator. + * @param comp A functor to use for comparisons. + * @return Nothing. + * + * Merges two sorted and consecutive ranges, [first,middle) and + * [middle,last), and puts the result in [first,last). The output will + * be sorted. The sort is @e stable, that is, for equivalent + * elements in the two ranges, elements from the first range will always + * come before elements from the second. + * + * If enough additional memory is available, this takes (last-first)-1 + * comparisons. Otherwise an NlogN algorithm is used, where N is + * distance(first,last). + * + * The comparison function should have the same effects on ordering as + * the function used for the initial sort. + */ + template + void + inplace_merge(_BidirectionalIterator __first, + _BidirectionalIterator __middle, + _BidirectionalIterator __last, + _Compare __comp) + { + typedef typename iterator_traits<_BidirectionalIterator>::value_type + _ValueType; + typedef typename iterator_traits<_BidirectionalIterator>::difference_type + _DistanceType; + + // concept requirements + __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept< + _BidirectionalIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + _ValueType, _ValueType>) + __glibcxx_requires_sorted_pred(__first, __middle, __comp); + __glibcxx_requires_sorted_pred(__middle, __last, __comp); + + if (__first == __middle || __middle == __last) + return; + + const _DistanceType __len1 = std::distance(__first, __middle); + const _DistanceType __len2 = std::distance(__middle, __last); + + _Temporary_buffer<_BidirectionalIterator, _ValueType> __buf(__first, + __last); + if (__buf.begin() == 0) + std::__merge_without_buffer(__first, __middle, __last, __len1, + __len2, __comp); + else + std::__merge_adaptive(__first, __middle, __last, __len1, __len2, + __buf.begin(), _DistanceType(__buf.size()), + __comp); + } + + template + void + __merge_sort_loop(_RandomAccessIterator1 __first, + _RandomAccessIterator1 __last, + _RandomAccessIterator2 __result, + _Distance __step_size) + { + const _Distance __two_step = 2 * __step_size; + + while (__last - __first >= __two_step) + { + __result = std::merge(__first, __first + __step_size, + __first + __step_size, __first + __two_step, + __result); + __first += __two_step; + } + + __step_size = std::min(_Distance(__last - __first), __step_size); + std::merge(__first, __first + __step_size, __first + __step_size, __last, + __result); + } + + template + void + __merge_sort_loop(_RandomAccessIterator1 __first, + _RandomAccessIterator1 __last, + _RandomAccessIterator2 __result, _Distance __step_size, + _Compare __comp) + { + const _Distance __two_step = 2 * __step_size; + + while (__last - __first >= __two_step) + { + __result = std::merge(__first, __first + __step_size, + __first + __step_size, __first + __two_step, + __result, + __comp); + __first += __two_step; + } + __step_size = std::min(_Distance(__last - __first), __step_size); + + std::merge(__first, __first + __step_size, + __first + __step_size, __last, + __result, + __comp); + } + + template + void + __chunk_insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Distance __chunk_size) + { + while (__last - __first >= __chunk_size) + { + std::__insertion_sort(__first, __first + __chunk_size); + __first += __chunk_size; + } + std::__insertion_sort(__first, __last); + } + + template + void + __chunk_insertion_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Distance __chunk_size, _Compare __comp) + { + while (__last - __first >= __chunk_size) + { + std::__insertion_sort(__first, __first + __chunk_size, __comp); + __first += __chunk_size; + } + std::__insertion_sort(__first, __last, __comp); + } + + enum { _S_chunk_size = 7 }; + + template + void + __merge_sort_with_buffer(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Pointer __buffer) + { + typedef typename iterator_traits<_RandomAccessIterator>::difference_type + _Distance; - // concept requirements - __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< - _RandomAccessIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _ValueType, _ValueType>) - __glibcxx_requires_valid_range(__first, __nth); - __glibcxx_requires_valid_range(__nth, __last); + const _Distance __len = __last - __first; + const _Pointer __buffer_last = __buffer + __len; - if (__first == __last || __nth == __last) - return; + _Distance __step_size = _S_chunk_size; + std::__chunk_insertion_sort(__first, __last, __step_size); - std::__introselect(__first, __nth, __last, - std::__lg(__last - __first) * 2, __comp); + while (__step_size < __len) + { + std::__merge_sort_loop(__first, __last, __buffer, __step_size); + __step_size *= 2; + std::__merge_sort_loop(__buffer, __buffer_last, __first, __step_size); + __step_size *= 2; + } } - /** - * @brief Finds the largest subrange in which @a val could be inserted - * at any place in it without changing the ordering. - * @param first An iterator. - * @param last Another iterator. - * @param val The search term. - * @return An pair of iterators defining the subrange. - * @ingroup binarysearch - * - * This is equivalent to - * @code - * std::make_pair(lower_bound(first, last, val), - * upper_bound(first, last, val)) - * @endcode - * but does not actually call those functions. - */ - template - pair<_ForwardIterator, _ForwardIterator> - equal_range(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val) + template + void + __merge_sort_with_buffer(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Pointer __buffer, _Compare __comp) { - typedef typename iterator_traits<_ForwardIterator>::value_type - _ValueType; - typedef typename iterator_traits<_ForwardIterator>::difference_type - _DistanceType; + typedef typename iterator_traits<_RandomAccessIterator>::difference_type + _Distance; - // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>) - __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>) - __glibcxx_requires_partitioned(__first, __last, __val); + const _Distance __len = __last - __first; + const _Pointer __buffer_last = __buffer + __len; - _DistanceType __len = std::distance(__first, __last); - _DistanceType __half; - _ForwardIterator __middle, __left, __right; + _Distance __step_size = _S_chunk_size; + std::__chunk_insertion_sort(__first, __last, __step_size, __comp); - while (__len > 0) + while (__step_size < __len) { - __half = __len >> 1; - __middle = __first; - std::advance(__middle, __half); - if (*__middle < __val) - { - __first = __middle; - ++__first; - __len = __len - __half - 1; - } - else if (__val < *__middle) - __len = __half; - else - { - __left = std::lower_bound(__first, __middle, __val); - std::advance(__first, __len); - __right = std::upper_bound(++__middle, __first, __val); - return pair<_ForwardIterator, _ForwardIterator>(__left, __right); - } + std::__merge_sort_loop(__first, __last, __buffer, + __step_size, __comp); + __step_size *= 2; + std::__merge_sort_loop(__buffer, __buffer_last, __first, + __step_size, __comp); + __step_size *= 2; } - return pair<_ForwardIterator, _ForwardIterator>(__first, __first); } - /** - * @brief Finds the largest subrange in which @a val could be inserted - * at any place in it without changing the ordering. - * @param first An iterator. - * @param last Another iterator. - * @param val The search term. - * @param comp A functor to use for comparisons. - * @return An pair of iterators defining the subrange. - * @ingroup binarysearch - * - * This is equivalent to - * @code - * std::make_pair(lower_bound(first, last, val, comp), - * upper_bound(first, last, val, comp)) - * @endcode - * but does not actually call those functions. - */ - template - pair<_ForwardIterator, _ForwardIterator> - equal_range(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val, - _Compare __comp) + template + void + __stable_sort_adaptive(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Pointer __buffer, _Distance __buffer_size) { - typedef typename iterator_traits<_ForwardIterator>::value_type - _ValueType; - typedef typename iterator_traits<_ForwardIterator>::difference_type - _DistanceType; + const _Distance __len = (__last - __first + 1) / 2; + const _RandomAccessIterator __middle = __first + __len; + if (__len > __buffer_size) + { + std::__stable_sort_adaptive(__first, __middle, + __buffer, __buffer_size); + std::__stable_sort_adaptive(__middle, __last, + __buffer, __buffer_size); + } + else + { + std::__merge_sort_with_buffer(__first, __middle, __buffer); + std::__merge_sort_with_buffer(__middle, __last, __buffer); + } + std::__merge_adaptive(__first, __middle, __last, + _Distance(__middle - __first), + _Distance(__last - __middle), + __buffer, __buffer_size); + } - // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _ValueType, _Tp>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _Tp, _ValueType>) - __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); + template + void + __stable_sort_adaptive(_RandomAccessIterator __first, + _RandomAccessIterator __last, + _Pointer __buffer, _Distance __buffer_size, + _Compare __comp) + { + const _Distance __len = (__last - __first + 1) / 2; + const _RandomAccessIterator __middle = __first + __len; + if (__len > __buffer_size) + { + std::__stable_sort_adaptive(__first, __middle, __buffer, + __buffer_size, __comp); + std::__stable_sort_adaptive(__middle, __last, __buffer, + __buffer_size, __comp); + } + else + { + std::__merge_sort_with_buffer(__first, __middle, __buffer, __comp); + std::__merge_sort_with_buffer(__middle, __last, __buffer, __comp); + } + std::__merge_adaptive(__first, __middle, __last, + _Distance(__middle - __first), + _Distance(__last - __middle), + __buffer, __buffer_size, + __comp); + } - _DistanceType __len = std::distance(__first, __last); - _DistanceType __half; - _ForwardIterator __middle, __left, __right; + /** + * @if maint + * This is a helper function for the stable sorting routines. + * @endif + */ + template + void + __inplace_stable_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last) + { + if (__last - __first < 15) + { + std::__insertion_sort(__first, __last); + return; + } + _RandomAccessIterator __middle = __first + (__last - __first) / 2; + std::__inplace_stable_sort(__first, __middle); + std::__inplace_stable_sort(__middle, __last); + std::__merge_without_buffer(__first, __middle, __last, + __middle - __first, + __last - __middle); + } - while (__len > 0) + /** + * @if maint + * This is a helper function for the stable sorting routines. + * @endif + */ + template + void + __inplace_stable_sort(_RandomAccessIterator __first, + _RandomAccessIterator __last, _Compare __comp) + { + if (__last - __first < 15) { - __half = __len >> 1; - __middle = __first; - std::advance(__middle, __half); - if (__comp(*__middle, __val)) - { - __first = __middle; - ++__first; - __len = __len - __half - 1; - } - else if (__comp(__val, *__middle)) - __len = __half; - else - { - __left = std::lower_bound(__first, __middle, __val, __comp); - std::advance(__first, __len); - __right = std::upper_bound(++__middle, __first, __val, __comp); - return pair<_ForwardIterator, _ForwardIterator>(__left, __right); - } + std::__insertion_sort(__first, __last, __comp); + return; } - return pair<_ForwardIterator, _ForwardIterator>(__first, __first); + _RandomAccessIterator __middle = __first + (__last - __first) / 2; + std::__inplace_stable_sort(__first, __middle, __comp); + std::__inplace_stable_sort(__middle, __last, __comp); + std::__merge_without_buffer(__first, __middle, __last, + __middle - __first, + __last - __middle, + __comp); } /** - * @brief Determines whether an element exists in a range. + * @brief Sort the elements of a sequence, preserving the relative order + * of equivalent elements. * @param first An iterator. * @param last Another iterator. - * @param val The search term. - * @return True if @a val (or its equivelent) is in [@a first,@a last ]. - * @ingroup binarysearch + * @return Nothing. * - * Note that this does not actually return an iterator to @a val. For - * that, use std::find or a container's specialized find member functions. + * Sorts the elements in the range @p [first,last) in ascending order, + * such that @p *(i+1)<*i is false for each iterator @p i in the range + * @p [first,last-1). + * + * The relative ordering of equivalent elements is preserved, so any two + * elements @p x and @p y in the range @p [first,last) such that + * @p x - bool - binary_search(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val) + template + inline void + stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last) { - typedef typename iterator_traits<_ForwardIterator>::value_type + typedef typename iterator_traits<_RandomAccessIterator>::value_type _ValueType; + typedef typename iterator_traits<_RandomAccessIterator>::difference_type + _DistanceType; // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_LessThanOpConcept<_Tp, _ValueType>) - __glibcxx_requires_partitioned(__first, __last, __val); + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) + __glibcxx_function_requires(_LessThanComparableConcept<_ValueType>) + __glibcxx_requires_valid_range(__first, __last); - _ForwardIterator __i = std::lower_bound(__first, __last, __val); - return __i != __last && !(__val < *__i); + _Temporary_buffer<_RandomAccessIterator, _ValueType> __buf(__first, + __last); + if (__buf.begin() == 0) + std::__inplace_stable_sort(__first, __last); + else + std::__stable_sort_adaptive(__first, __last, __buf.begin(), + _DistanceType(__buf.size())); } /** - * @brief Determines whether an element exists in a range. + * @brief Sort the elements of a sequence using a predicate for comparison, + * preserving the relative order of equivalent elements. * @param first An iterator. * @param last Another iterator. - * @param val The search term. - * @param comp A functor to use for comparisons. - * @return True if @a val (or its equivelent) is in [@a first,@a last ]. - * @ingroup binarysearch + * @param comp A comparison functor. + * @return Nothing. * - * Note that this does not actually return an iterator to @a val. For - * that, use std::find or a container's specialized find member functions. + * Sorts the elements in the range @p [first,last) in ascending order, + * such that @p comp(*(i+1),*i) is false for each iterator @p i in the + * range @p [first,last-1). * - * The comparison function should have the same effects on ordering as - * the function used for the initial sort. + * The relative ordering of equivalent elements is preserved, so any two + * elements @p x and @p y in the range @p [first,last) such that + * @p comp(x,y) is false and @p comp(y,x) is false will have the same + * relative ordering after calling @p stable_sort(). */ - template - bool - binary_search(_ForwardIterator __first, _ForwardIterator __last, - const _Tp& __val, _Compare __comp) + template + inline void + stable_sort(_RandomAccessIterator __first, _RandomAccessIterator __last, + _Compare __comp) { - typedef typename iterator_traits<_ForwardIterator>::value_type + typedef typename iterator_traits<_RandomAccessIterator>::value_type _ValueType; + typedef typename iterator_traits<_RandomAccessIterator>::difference_type + _DistanceType; // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_Mutable_RandomAccessIteratorConcept< + _RandomAccessIterator>) __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - _Tp, _ValueType>) - __glibcxx_requires_partitioned_pred(__first, __last, __val, __comp); + _ValueType, + _ValueType>) + __glibcxx_requires_valid_range(__first, __last); - _ForwardIterator __i = std::lower_bound(__first, __last, __val, __comp); - return __i != __last && !bool(__comp(__val, *__i)); + _Temporary_buffer<_RandomAccessIterator, _ValueType> __buf(__first, + __last); + if (__buf.begin() == 0) + std::__inplace_stable_sort(__first, __last, __comp); + else + std::__stable_sort_adaptive(__first, __last, __buf.begin(), + _DistanceType(__buf.size()), __comp); } // Set algorithms: includes, set_union, set_intersection, set_difference, @@ -4896,59 +5183,6 @@ _GLIBCXX_BEGIN_NAMESPACE(std) // min_element and max_element, with and without an explicitly supplied // comparison function. - /** - * @brief Return the maximum element in a range. - * @param first Start of range. - * @param last End of range. - * @return Iterator referencing the first instance of the largest value. - */ - template - _ForwardIterator - max_element(_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 __first; - _ForwardIterator __result = __first; - while (++__first != __last) - if (*__result < *__first) - __result = __first; - return __result; - } - - /** - * @brief Return the maximum element in a range using comparison functor. - * @param first Start of range. - * @param last End of range. - * @param comp Comparison functor. - * @return Iterator referencing the first instance of the largest value - * according to comp. - */ - template - _ForwardIterator - max_element(_ForwardIterator __first, _ForwardIterator __last, - _Compare __comp) - { - // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - typename iterator_traits<_ForwardIterator>::value_type, - typename iterator_traits<_ForwardIterator>::value_type>) - __glibcxx_requires_valid_range(__first, __last); - - if (__first == __last) return __first; - _ForwardIterator __result = __first; - while (++__first != __last) - if (__comp(*__result, *__first)) - __result = __first; - return __result; - } - /** * @brief Return the minimum element in a range. * @param first Start of range. @@ -5003,197 +5237,82 @@ _GLIBCXX_BEGIN_NAMESPACE(std) return __result; } - // next_permutation and prev_permutation, with and without an explicitly - // supplied comparison function. - /** - * @brief Permute range into the next "dictionary" ordering. + * @brief Return the maximum element in a range. * @param first Start of range. * @param last End of range. - * @return False if wrapped to first permutation, true otherwise. - * - * Treats all permutations of the range as a set of "dictionary" sorted - * sequences. Permutes the current sequence into the next one of this set. - * Returns true if there are more sequences to generate. If the sequence - * is the largest of the set, the smallest is generated and false returned. + * @return Iterator referencing the first instance of the largest value. */ - template - bool - next_permutation(_BidirectionalIterator __first, - _BidirectionalIterator __last) + template + _ForwardIterator + max_element(_ForwardIterator __first, _ForwardIterator __last) { // concept requirements - __glibcxx_function_requires(_BidirectionalIteratorConcept< - _BidirectionalIterator>) + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) __glibcxx_function_requires(_LessThanComparableConcept< - typename iterator_traits<_BidirectionalIterator>::value_type>) - __glibcxx_requires_valid_range(__first, __last); - - if (__first == __last) - return false; - _BidirectionalIterator __i = __first; - ++__i; - if (__i == __last) - return false; - __i = __last; - --__i; - - for(;;) - { - _BidirectionalIterator __ii = __i; - --__i; - if (*__i < *__ii) - { - _BidirectionalIterator __j = __last; - while (!(*__i < *--__j)) - {} - std::iter_swap(__i, __j); - std::reverse(__ii, __last); - return true; - } - if (__i == __first) - { - std::reverse(__first, __last); - return false; - } - } - } - - /** - * @brief Permute range into the next "dictionary" ordering using - * comparison functor. - * @param first Start of range. - * @param last End of range. - * @param comp - * @return False if wrapped to first permutation, true otherwise. - * - * Treats all permutations of the range [first,last) as a set of - * "dictionary" sorted sequences ordered by @a comp. Permutes the current - * sequence into the next one of this set. Returns true if there are more - * sequences to generate. If the sequence is the largest of the set, the - * smallest is generated and false returned. - */ - template - bool - next_permutation(_BidirectionalIterator __first, - _BidirectionalIterator __last, _Compare __comp) - { - // concept requirements - __glibcxx_function_requires(_BidirectionalIteratorConcept< - _BidirectionalIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - typename iterator_traits<_BidirectionalIterator>::value_type, - typename iterator_traits<_BidirectionalIterator>::value_type>) + typename iterator_traits<_ForwardIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); if (__first == __last) - return false; - _BidirectionalIterator __i = __first; - ++__i; - if (__i == __last) - return false; - __i = __last; - --__i; - - for(;;) - { - _BidirectionalIterator __ii = __i; - --__i; - if (__comp(*__i, *__ii)) - { - _BidirectionalIterator __j = __last; - while (!bool(__comp(*__i, *--__j))) - {} - std::iter_swap(__i, __j); - std::reverse(__ii, __last); - return true; - } - if (__i == __first) - { - std::reverse(__first, __last); - return false; - } - } + return __first; + _ForwardIterator __result = __first; + while (++__first != __last) + if (*__result < *__first) + __result = __first; + return __result; } /** - * @brief Permute range into the previous "dictionary" ordering. + * @brief Return the maximum element in a range using comparison functor. * @param first Start of range. * @param last End of range. - * @return False if wrapped to last permutation, true otherwise. - * - * Treats all permutations of the range as a set of "dictionary" sorted - * sequences. Permutes the current sequence into the previous one of this - * set. Returns true if there are more sequences to generate. If the - * sequence is the smallest of the set, the largest is generated and false - * returned. + * @param comp Comparison functor. + * @return Iterator referencing the first instance of the largest value + * according to comp. */ - template - bool - prev_permutation(_BidirectionalIterator __first, - _BidirectionalIterator __last) + template + _ForwardIterator + max_element(_ForwardIterator __first, _ForwardIterator __last, + _Compare __comp) { // concept requirements - __glibcxx_function_requires(_BidirectionalIteratorConcept< - _BidirectionalIterator>) - __glibcxx_function_requires(_LessThanComparableConcept< - typename iterator_traits<_BidirectionalIterator>::value_type>) + __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + typename iterator_traits<_ForwardIterator>::value_type, + typename iterator_traits<_ForwardIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); - if (__first == __last) - return false; - _BidirectionalIterator __i = __first; - ++__i; - if (__i == __last) - return false; - __i = __last; - --__i; - - for(;;) - { - _BidirectionalIterator __ii = __i; - --__i; - if (*__ii < *__i) - { - _BidirectionalIterator __j = __last; - while (!(*--__j < *__i)) - {} - std::iter_swap(__i, __j); - std::reverse(__ii, __last); - return true; - } - if (__i == __first) - { - std::reverse(__first, __last); - return false; - } - } + if (__first == __last) return __first; + _ForwardIterator __result = __first; + while (++__first != __last) + if (__comp(*__result, *__first)) + __result = __first; + return __result; } + // next_permutation and prev_permutation, with and without an explicitly + // supplied comparison function. + /** - * @brief Permute range into the previous "dictionary" ordering using - * comparison functor. + * @brief Permute range into the next "dictionary" ordering. * @param first Start of range. * @param last End of range. - * @param comp - * @return False if wrapped to last permutation, true otherwise. + * @return False if wrapped to first permutation, true otherwise. * - * Treats all permutations of the range [first,last) as a set of - * "dictionary" sorted sequences ordered by @a comp. Permutes the current - * sequence into the previous one of this set. Returns true if there are - * more sequences to generate. If the sequence is the smallest of the set, - * the largest is generated and false returned. + * Treats all permutations of the range as a set of "dictionary" sorted + * sequences. Permutes the current sequence into the next one of this set. + * Returns true if there are more sequences to generate. If the sequence + * is the largest of the set, the smallest is generated and false returned. */ - template + template bool - prev_permutation(_BidirectionalIterator __first, - _BidirectionalIterator __last, _Compare __comp) + next_permutation(_BidirectionalIterator __first, + _BidirectionalIterator __last) { // concept requirements __glibcxx_function_requires(_BidirectionalIteratorConcept< _BidirectionalIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, - typename iterator_traits<_BidirectionalIterator>::value_type, + __glibcxx_function_requires(_LessThanComparableConcept< typename iterator_traits<_BidirectionalIterator>::value_type>) __glibcxx_requires_valid_range(__first, __last); @@ -5210,320 +5329,189 @@ _GLIBCXX_BEGIN_NAMESPACE(std) { _BidirectionalIterator __ii = __i; --__i; - if (__comp(*__ii, *__i)) + if (*__i < *__ii) { _BidirectionalIterator __j = __last; - while (!bool(__comp(*--__j, *__i))) - {} - std::iter_swap(__i, __j); - std::reverse(__ii, __last); - return true; - } - if (__i == __first) - { - std::reverse(__first, __last); - return false; - } - } - } - - // find_first_of, with and without an explicitly supplied comparison function. - - /** - * @brief Find element from a set in a sequence. - * @param first1 Start of range to search. - * @param last1 End of range to search. - * @param first2 Start of match candidates. - * @param last2 End of match candidates. - * @return The first iterator @c i in the range - * @p [first1,last1) such that @c *i == @p *(i2) such that i2 is an - * interator in [first2,last2), or @p last1 if no such iterator exists. - * - * Searches the range @p [first1,last1) for an element that is equal to - * some element in the range [first2,last2). If found, returns an iterator - * in the range [first1,last1), otherwise returns @p last1. - */ - template - _InputIterator - find_first_of(_InputIterator __first1, _InputIterator __last1, - _ForwardIterator __first2, _ForwardIterator __last2) - { - // concept requirements - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_EqualOpConcept< - typename iterator_traits<_InputIterator>::value_type, - typename iterator_traits<_ForwardIterator>::value_type>) - __glibcxx_requires_valid_range(__first1, __last1); - __glibcxx_requires_valid_range(__first2, __last2); - - for ( ; __first1 != __last1; ++__first1) - for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter) - if (*__first1 == *__iter) - return __first1; - return __last1; - } - - /** - * @brief Find element from a set in a sequence using a predicate. - * @param first1 Start of range to search. - * @param last1 End of range to search. - * @param first2 Start of match candidates. - * @param last2 End of match candidates. - * @param comp Predicate to use. - * @return The first iterator @c i in the range - * @p [first1,last1) such that @c comp(*i, @p *(i2)) is true and i2 is an - * interator in [first2,last2), or @p last1 if no such iterator exists. - * - * Searches the range @p [first1,last1) for an element that is equal to - * some element in the range [first2,last2). If found, returns an iterator in - * the range [first1,last1), otherwise returns @p last1. - */ - template - _InputIterator - find_first_of(_InputIterator __first1, _InputIterator __last1, - _ForwardIterator __first2, _ForwardIterator __last2, - _BinaryPredicate __comp) - { - // concept requirements - __glibcxx_function_requires(_InputIteratorConcept<_InputIterator>) - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) - __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, - typename iterator_traits<_InputIterator>::value_type, - typename iterator_traits<_ForwardIterator>::value_type>) - __glibcxx_requires_valid_range(__first1, __last1); - __glibcxx_requires_valid_range(__first2, __last2); - - for ( ; __first1 != __last1; ++__first1) - for (_ForwardIterator __iter = __first2; __iter != __last2; ++__iter) - if (__comp(*__first1, *__iter)) - return __first1; - return __last1; - } - - - // find_end, with and without an explicitly supplied comparison function. - // Search [first2, last2) as a subsequence in [first1, last1), and return - // the *last* possible match. Note that find_end for bidirectional iterators - // is much faster than for forward iterators. - - // find_end for forward iterators. - template - _ForwardIterator1 - __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, - _ForwardIterator2 __first2, _ForwardIterator2 __last2, - forward_iterator_tag, forward_iterator_tag) - { - if (__first2 == __last2) - return __last1; - else - { - _ForwardIterator1 __result = __last1; - while (1) - { - _ForwardIterator1 __new_result - = std::search(__first1, __last1, __first2, __last2); - if (__new_result == __last1) - return __result; - else - { - __result = __new_result; - __first1 = __new_result; - ++__first1; - } - } - } - } - - template - _ForwardIterator1 - __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, - _ForwardIterator2 __first2, _ForwardIterator2 __last2, - forward_iterator_tag, forward_iterator_tag, - _BinaryPredicate __comp) - { - if (__first2 == __last2) - return __last1; - else - { - _ForwardIterator1 __result = __last1; - while (1) - { - _ForwardIterator1 __new_result - = std::search(__first1, __last1, __first2, __last2, __comp); - if (__new_result == __last1) - return __result; - else - { - __result = __new_result; - __first1 = __new_result; - ++__first1; - } - } - } - } - - // find_end for bidirectional iterators. Requires partial specialization. - template - _BidirectionalIterator1 - __find_end(_BidirectionalIterator1 __first1, - _BidirectionalIterator1 __last1, - _BidirectionalIterator2 __first2, - _BidirectionalIterator2 __last2, - bidirectional_iterator_tag, bidirectional_iterator_tag) - { - // concept requirements - __glibcxx_function_requires(_BidirectionalIteratorConcept< - _BidirectionalIterator1>) - __glibcxx_function_requires(_BidirectionalIteratorConcept< - _BidirectionalIterator2>) - - typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1; - typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2; - - _RevIterator1 __rlast1(__first1); - _RevIterator2 __rlast2(__first2); - _RevIterator1 __rresult = std::search(_RevIterator1(__last1), __rlast1, - _RevIterator2(__last2), __rlast2); - - if (__rresult == __rlast1) - return __last1; - else - { - _BidirectionalIterator1 __result = __rresult.base(); - std::advance(__result, -std::distance(__first2, __last2)); - return __result; + while (!(*__i < *--__j)) + {} + std::iter_swap(__i, __j); + std::reverse(__ii, __last); + return true; + } + if (__i == __first) + { + std::reverse(__first, __last); + return false; + } } } - template - _BidirectionalIterator1 - __find_end(_BidirectionalIterator1 __first1, - _BidirectionalIterator1 __last1, - _BidirectionalIterator2 __first2, - _BidirectionalIterator2 __last2, - bidirectional_iterator_tag, bidirectional_iterator_tag, - _BinaryPredicate __comp) + /** + * @brief Permute range into the next "dictionary" ordering using + * comparison functor. + * @param first Start of range. + * @param last End of range. + * @param comp + * @return False if wrapped to first permutation, true otherwise. + * + * Treats all permutations of the range [first,last) as a set of + * "dictionary" sorted sequences ordered by @a comp. Permutes the current + * sequence into the next one of this set. Returns true if there are more + * sequences to generate. If the sequence is the largest of the set, the + * smallest is generated and false returned. + */ + template + bool + next_permutation(_BidirectionalIterator __first, + _BidirectionalIterator __last, _Compare __comp) { // concept requirements __glibcxx_function_requires(_BidirectionalIteratorConcept< - _BidirectionalIterator1>) - __glibcxx_function_requires(_BidirectionalIteratorConcept< - _BidirectionalIterator2>) - - typedef reverse_iterator<_BidirectionalIterator1> _RevIterator1; - typedef reverse_iterator<_BidirectionalIterator2> _RevIterator2; + _BidirectionalIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + typename iterator_traits<_BidirectionalIterator>::value_type, + typename iterator_traits<_BidirectionalIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); - _RevIterator1 __rlast1(__first1); - _RevIterator2 __rlast2(__first2); - _RevIterator1 __rresult = std::search(_RevIterator1(__last1), __rlast1, - _RevIterator2(__last2), __rlast2, - __comp); + if (__first == __last) + return false; + _BidirectionalIterator __i = __first; + ++__i; + if (__i == __last) + return false; + __i = __last; + --__i; - if (__rresult == __rlast1) - return __last1; - else + for(;;) { - _BidirectionalIterator1 __result = __rresult.base(); - std::advance(__result, -std::distance(__first2, __last2)); - return __result; + _BidirectionalIterator __ii = __i; + --__i; + if (__comp(*__i, *__ii)) + { + _BidirectionalIterator __j = __last; + while (!bool(__comp(*__i, *--__j))) + {} + std::iter_swap(__i, __j); + std::reverse(__ii, __last); + return true; + } + if (__i == __first) + { + std::reverse(__first, __last); + return false; + } } } - // Dispatching functions for find_end. - /** - * @brief Find last matching subsequence in a sequence. - * @param first1 Start of range to search. - * @param last1 End of range to search. - * @param first2 Start of sequence to match. - * @param last2 End of sequence to match. - * @return The last iterator @c i in the range - * @p [first1,last1-(last2-first2)) such that @c *(i+N) == @p *(first2+N) - * for each @c N in the range @p [0,last2-first2), or @p last1 if no - * such iterator exists. - * - * Searches the range @p [first1,last1) for a sub-sequence that compares - * equal value-by-value with the sequence given by @p [first2,last2) and - * returns an iterator to the first element of the sub-sequence, or - * @p last1 if the sub-sequence is not found. The sub-sequence will be the - * last such subsequence contained in [first,last1). + * @brief Permute range into the previous "dictionary" ordering. + * @param first Start of range. + * @param last End of range. + * @return False if wrapped to last permutation, true otherwise. * - * Because the sub-sequence must lie completely within the range - * @p [first1,last1) it must start at a position less than - * @p last1-(last2-first2) where @p last2-first2 is the length of the - * sub-sequence. - * This means that the returned iterator @c i will be in the range - * @p [first1,last1-(last2-first2)) + * Treats all permutations of the range as a set of "dictionary" sorted + * sequences. Permutes the current sequence into the previous one of this + * set. Returns true if there are more sequences to generate. If the + * sequence is the smallest of the set, the largest is generated and false + * returned. */ - template - inline _ForwardIterator1 - find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, - _ForwardIterator2 __first2, _ForwardIterator2 __last2) + template + bool + prev_permutation(_BidirectionalIterator __first, + _BidirectionalIterator __last) { // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>) - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>) - __glibcxx_function_requires(_EqualOpConcept< - typename iterator_traits<_ForwardIterator1>::value_type, - typename iterator_traits<_ForwardIterator2>::value_type>) - __glibcxx_requires_valid_range(__first1, __last1); - __glibcxx_requires_valid_range(__first2, __last2); + __glibcxx_function_requires(_BidirectionalIteratorConcept< + _BidirectionalIterator>) + __glibcxx_function_requires(_LessThanComparableConcept< + typename iterator_traits<_BidirectionalIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); - return std::__find_end(__first1, __last1, __first2, __last2, - std::__iterator_category(__first1), - std::__iterator_category(__first2)); + if (__first == __last) + return false; + _BidirectionalIterator __i = __first; + ++__i; + if (__i == __last) + return false; + __i = __last; + --__i; + + for(;;) + { + _BidirectionalIterator __ii = __i; + --__i; + if (*__ii < *__i) + { + _BidirectionalIterator __j = __last; + while (!(*--__j < *__i)) + {} + std::iter_swap(__i, __j); + std::reverse(__ii, __last); + return true; + } + if (__i == __first) + { + std::reverse(__first, __last); + return false; + } + } } /** - * @brief Find last matching subsequence in a sequence using a predicate. - * @param first1 Start of range to search. - * @param last1 End of range to search. - * @param first2 Start of sequence to match. - * @param last2 End of sequence to match. - * @param comp The predicate to use. - * @return The last iterator @c i in the range - * @p [first1,last1-(last2-first2)) such that @c predicate(*(i+N), @p - * (first2+N)) is true for each @c N in the range @p [0,last2-first2), or - * @p last1 if no such iterator exists. - * - * Searches the range @p [first1,last1) for a sub-sequence that compares - * equal value-by-value with the sequence given by @p [first2,last2) using - * comp as a predicate and returns an iterator to the first element of the - * sub-sequence, or @p last1 if the sub-sequence is not found. The - * sub-sequence will be the last such subsequence contained in - * [first,last1). + * @brief Permute range into the previous "dictionary" ordering using + * comparison functor. + * @param first Start of range. + * @param last End of range. + * @param comp + * @return False if wrapped to last permutation, true otherwise. * - * Because the sub-sequence must lie completely within the range - * @p [first1,last1) it must start at a position less than - * @p last1-(last2-first2) where @p last2-first2 is the length of the - * sub-sequence. - * This means that the returned iterator @c i will be in the range - * @p [first1,last1-(last2-first2)) + * Treats all permutations of the range [first,last) as a set of + * "dictionary" sorted sequences ordered by @a comp. Permutes the current + * sequence into the previous one of this set. Returns true if there are + * more sequences to generate. If the sequence is the smallest of the set, + * the largest is generated and false returned. */ - template - inline _ForwardIterator1 - find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, - _ForwardIterator2 __first2, _ForwardIterator2 __last2, - _BinaryPredicate __comp) + template + bool + prev_permutation(_BidirectionalIterator __first, + _BidirectionalIterator __last, _Compare __comp) { // concept requirements - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator1>) - __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator2>) - __glibcxx_function_requires(_BinaryPredicateConcept<_BinaryPredicate, - typename iterator_traits<_ForwardIterator1>::value_type, - typename iterator_traits<_ForwardIterator2>::value_type>) - __glibcxx_requires_valid_range(__first1, __last1); - __glibcxx_requires_valid_range(__first2, __last2); + __glibcxx_function_requires(_BidirectionalIteratorConcept< + _BidirectionalIterator>) + __glibcxx_function_requires(_BinaryPredicateConcept<_Compare, + typename iterator_traits<_BidirectionalIterator>::value_type, + typename iterator_traits<_BidirectionalIterator>::value_type>) + __glibcxx_requires_valid_range(__first, __last); - return std::__find_end(__first1, __last1, __first2, __last2, - std::__iterator_category(__first1), - std::__iterator_category(__first2), - __comp); + if (__first == __last) + return false; + _BidirectionalIterator __i = __first; + ++__i; + if (__i == __last) + return false; + __i = __last; + --__i; + + for(;;) + { + _BidirectionalIterator __ii = __i; + --__i; + if (__comp(*__ii, *__i)) + { + _BidirectionalIterator __j = __last; + while (!bool(__comp(*--__j, *__i))) + {} + std::iter_swap(__i, __j); + std::reverse(__ii, __last); + return true; + } + if (__i == __first) + { + std::reverse(__first, __last); + return false; + } + } } _GLIBCXX_END_NAMESPACE