// Copyright (c) 2000 David Abrahams. // Distributed under the Boost Software License, Version 1.0. // (See accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) // // Copyright (c) 1994 // Hewlett-Packard Company // // Permission to use, copy, modify, distribute and sell this software // and its documentation for any purpose is hereby granted without fee, // provided that the above copyright notice appear in all copies and // that both that copyright notice and this permission notice appear // in supporting documentation. Hewlett-Packard Company makes no // representations about the suitability of this software for any // purpose. It is provided "as is" without express or implied warranty. // // Copyright (c) 1996 // Silicon Graphics Computer Systems, Inc. // // Permission to use, copy, modify, distribute and sell this software // and its documentation for any purpose is hereby granted without fee, // provided that the above copyright notice appear in all copies and // that both that copyright notice and this permission notice appear // in supporting documentation. Silicon Graphics makes no // representations about the suitability of this software for any // purpose. It is provided "as is" without express or implied warranty. // #ifndef BINARY_SEARCH_DWA_122600_H_ # define BINARY_SEARCH_DWA_122600_H_ # include <boost/detail/iterator.hpp> # include <utility> namespace boost { namespace detail { template <class ForwardIter, class Tp> ForwardIter lower_bound(ForwardIter first, ForwardIter last, const Tp& val) { typedef detail::iterator_traits<ForwardIter> traits; typename traits::difference_type len = boost::detail::distance(first, last); typename traits::difference_type half; ForwardIter 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; } template <class ForwardIter, class Tp, class Compare> ForwardIter lower_bound(ForwardIter first, ForwardIter last, const Tp& val, Compare comp) { typedef detail::iterator_traits<ForwardIter> traits; typename traits::difference_type len = boost::detail::distance(first, last); typename traits::difference_type half; ForwardIter middle; while (len > 0) { half = len >> 1; middle = first; std::advance(middle, half); if (comp(*middle, val)) { first = middle; ++first; len = len - half - 1; } else len = half; } return first; } template <class ForwardIter, class Tp> ForwardIter upper_bound(ForwardIter first, ForwardIter last, const Tp& val) { typedef detail::iterator_traits<ForwardIter> traits; typename traits::difference_type len = boost::detail::distance(first, last); typename traits::difference_type half; ForwardIter middle; while (len > 0) { half = len >> 1; middle = first; std::advance(middle, half); if (val < *middle) len = half; else { first = middle; ++first; len = len - half - 1; } } return first; } template <class ForwardIter, class Tp, class Compare> ForwardIter upper_bound(ForwardIter first, ForwardIter last, const Tp& val, Compare comp) { typedef detail::iterator_traits<ForwardIter> traits; typename traits::difference_type len = boost::detail::distance(first, last); typename traits::difference_type half; ForwardIter middle; while (len > 0) { half = len >> 1; middle = first; std::advance(middle, half); if (comp(val, *middle)) len = half; else { first = middle; ++first; len = len - half - 1; } } return first; } template <class ForwardIter, class Tp> std::pair<ForwardIter, ForwardIter> equal_range(ForwardIter first, ForwardIter last, const Tp& val) { typedef detail::iterator_traits<ForwardIter> traits; typename traits::difference_type len = boost::detail::distance(first, last); typename traits::difference_type half; ForwardIter middle, left, right; while (len > 0) { 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 = boost::detail::lower_bound(first, middle, val); std::advance(first, len); right = boost::detail::upper_bound(++middle, first, val); return std::pair<ForwardIter, ForwardIter>(left, right); } } return std::pair<ForwardIter, ForwardIter>(first, first); } template <class ForwardIter, class Tp, class Compare> std::pair<ForwardIter, ForwardIter> equal_range(ForwardIter first, ForwardIter last, const Tp& val, Compare comp) { typedef detail::iterator_traits<ForwardIter> traits; typename traits::difference_type len = boost::detail::distance(first, last); typename traits::difference_type half; ForwardIter middle, left, right; 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 = boost::detail::lower_bound(first, middle, val, comp); std::advance(first, len); right = boost::detail::upper_bound(++middle, first, val, comp); return std::pair<ForwardIter, ForwardIter>(left, right); } } return std::pair<ForwardIter, ForwardIter>(first, first); } template <class ForwardIter, class Tp> bool binary_search(ForwardIter first, ForwardIter last, const Tp& val) { ForwardIter i = boost::detail::lower_bound(first, last, val); return i != last && !(val < *i); } template <class ForwardIter, class Tp, class Compare> bool binary_search(ForwardIter first, ForwardIter last, const Tp& val, Compare comp) { ForwardIter i = boost::detail::lower_bound(first, last, val, comp); return i != last && !comp(val, *i); } }} // namespace boost::detail #endif // BINARY_SEARCH_DWA_122600_H_