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// 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_NDNBOOST_DWA_122600_H_
# define BINARY_SEARCH_NDNBOOST_DWA_122600_H_
# include <ndnboost/detail/iterator.hpp>
# include <utility>
namespace ndnboost { 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 = ndnboost::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 = ndnboost::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 = ndnboost::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 = ndnboost::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 = ndnboost::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 = ndnboost::detail::lower_bound(first, middle, val);
std::advance(first, len);
right = ndnboost::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 = ndnboost::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 = ndnboost::detail::lower_bound(first, middle, val, comp);
std::advance(first, len);
right = ndnboost::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 = ndnboost::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 = ndnboost::detail::lower_bound(first, last, val, comp);
return i != last && !comp(val, *i);
}
}} // namespace ndnboost::detail
#endif // BINARY_SEARCH_NDNBOOST_DWA_122600_H_