Sprout/sprout/algorithm/find_end.hpp
Mitsuru Kariya bfc22a86a7 Change find_end:
1.Fix for ForwardIterator when [first2, last2) is empty.
2.Fix RandomAccessIterator version.(search from last1)
3.Add BidirectionalIterator version.(search from last1)
4.Add sprout::detail::search_one_rev helper function for
  BidirectionalIterator version.
2013-08-28 13:24:15 +09:00

253 lines
10 KiB
C++

/*=============================================================================
Copyright (c) 2011-2013 Bolero MURAKAMI
https://github.com/bolero-MURAKAMI/Sprout
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)
=============================================================================*/
#ifndef SPROUT_ALGORITHM_FIND_END_HPP
#define SPROUT_ALGORITHM_FIND_END_HPP
#include <iterator>
#include <type_traits>
#include <sprout/config.hpp>
#include <sprout/iterator/operation.hpp>
#include <sprout/iterator/type_traits/category.hpp>
#include <sprout/functional/equal_to.hpp>
#include <sprout/utility/pair/pair.hpp>
#include <sprout/detail/algorithm/search_one.hpp>
#include <sprout/detail/algorithm/search_one_rev.hpp>
namespace sprout {
namespace detail {
template<typename RandomAccessIterator1>
inline SPROUT_CONSTEXPR RandomAccessIterator1
find_end_impl_check_ra(RandomAccessIterator1 first1, RandomAccessIterator1 last1_, RandomAccessIterator1 searched) {
return searched == first1 ? searched
: last1_
;
}
template<typename RandomAccessIterator1, typename RandomAccessIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR RandomAccessIterator1
find_end_impl_ra(
RandomAccessIterator1 first1, RandomAccessIterator1 last1,
RandomAccessIterator2 first2, RandomAccessIterator2 last2,
BinaryPredicate pred,
typename std::iterator_traits<RandomAccessIterator1>::difference_type pivot, RandomAccessIterator1 last1_,
RandomAccessIterator1 searched
)
{
return searched != last1_ ? searched
: pivot == 0
? sprout::detail::find_end_impl_check_ra(
first1, last1_,
sprout::detail::search_one(first1, last1_, first2, last2, pred)
)
: sprout::detail::find_end_impl_ra(
first1, sprout::next(first1, pivot), first2, last2, pred,
pivot / 2, last1_,
sprout::detail::find_end_impl_ra(
sprout::next(first1, pivot), last1, first2, last2, pred,
(sprout::distance(first1, last1) - pivot) / 2, last1_,
last1_
)
)
;
}
template<typename RandomAccessIterator1, typename RandomAccessIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR RandomAccessIterator1
find_end_impl_ra1(
RandomAccessIterator1 first1, RandomAccessIterator1 last1,
RandomAccessIterator2 first2, RandomAccessIterator2 last2,
BinaryPredicate pred,
typename std::iterator_traits<RandomAccessIterator1>::difference_type len1,
typename std::iterator_traits<RandomAccessIterator2>::difference_type len2
)
{
return len1 < len2 ? last1
: sprout::detail::find_end_impl_ra(
first1, last1 - len2 + 1, first2, last2, pred,
(len1 - len2 + 1) / 2, last1, last1
)
;
}
template<typename RandomAccessIterator1, typename RandomAccessIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR typename std::enable_if<
sprout::is_constant_distance_iterator<RandomAccessIterator1>::value
&& sprout::is_constant_distance_iterator<RandomAccessIterator2>::value,
RandomAccessIterator1
>::type
find_end(
RandomAccessIterator1 first1, RandomAccessIterator1 last1,
RandomAccessIterator2 first2, RandomAccessIterator2 last2,
BinaryPredicate pred,
std::random_access_iterator_tag*
)
{
return sprout::detail::find_end_impl_ra1(
first1, last1, first2, last2, pred,
sprout::distance(first1, last1), sprout::distance(first2, last2)
)
;
}
template<typename BidirectionalIterator1>
inline SPROUT_CONSTEXPR sprout::pair<BidirectionalIterator1, BidirectionalIterator1>
find_end_impl_check_bi(
sprout::pair<BidirectionalIterator1, BidirectionalIterator1> const& current,
BidirectionalIterator1 first1, sprout::pair<BidirectionalIterator1, bool> searched
)
{
typedef sprout::pair<BidirectionalIterator1, BidirectionalIterator1> type;
return searched.second ? type(first1, current.second)
: searched.first == current.first ? type(sprout::prev(current.first), current.second)
: type(current.first, searched.first)
;
}
template<typename BidirectionalIterator1, typename BidirectionalIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR sprout::pair<BidirectionalIterator1, BidirectionalIterator1>
find_end_impl_bi1(
sprout::pair<BidirectionalIterator1, BidirectionalIterator1> const& current,
BidirectionalIterator1 first1, BidirectionalIterator1 last1,
BidirectionalIterator2 first2, BidirectionalIterator2 last2, BinaryPredicate pred,
typename std::iterator_traits<BidirectionalIterator1>::difference_type n
)
{
return current.second != last1 || current.first == first1 ? current
: n == 1 ? sprout::detail::find_end_impl_check_bi(
current, first1,
sprout::detail::search_one_rev(first1, current.first, first2, last2, pred)
)
: sprout::detail::find_end_impl_bi1(
sprout::detail::find_end_impl_bi1(
current,
first1, last1, first2, last2, pred, n / 2
),
first1, last1, first2, last2, pred, n - n / 2
)
;
}
template<typename BidirectionalIterator1, typename BidirectionalIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR sprout::pair<BidirectionalIterator1, BidirectionalIterator1>
find_end_impl_bi(
sprout::pair<BidirectionalIterator1, BidirectionalIterator1> const& current,
BidirectionalIterator1 first1, BidirectionalIterator1 last1,
BidirectionalIterator2 first2, BidirectionalIterator2 last2, BinaryPredicate pred,
typename std::iterator_traits<BidirectionalIterator1>::difference_type n
)
{
return current.second != last1 || current.first == first1 ? current
: sprout::detail::find_end_impl_bi(
sprout::detail::find_end_impl_bi1(
current,
first1, last1, first2, last2, pred, n
),
first1, last1, first2, last2, pred, n * 2
)
;
}
template<typename BidirectionalIterator1, typename BidirectionalIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR BidirectionalIterator1
find_end(
BidirectionalIterator1 first1, BidirectionalIterator1 last1,
BidirectionalIterator2 first2, BidirectionalIterator2 last2,
BinaryPredicate pred,
std::bidirectional_iterator_tag*
)
{
typedef sprout::pair<BidirectionalIterator1, BidirectionalIterator1> type;
return sprout::detail::find_end_impl_bi(type(last1, last1), first1, last1, first2, last2, pred, 1).second;
}
template<typename ForwardIterator1>
inline SPROUT_CONSTEXPR sprout::pair<ForwardIterator1, ForwardIterator1>
find_end_impl_check(sprout::pair<ForwardIterator1, ForwardIterator1> const& current, ForwardIterator1 last1, ForwardIterator1 searched) {
typedef sprout::pair<ForwardIterator1, ForwardIterator1> type;
return searched == current.first ? type(sprout::next(current.first), searched)
: searched == last1 ? type(last1, current.second)
: type(sprout::next(current.first), current.second)
;
}
template<typename ForwardIterator1, typename ForwardIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR sprout::pair<ForwardIterator1, ForwardIterator1>
find_end_impl_1(
sprout::pair<ForwardIterator1, ForwardIterator1> const& current,
ForwardIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred,
typename std::iterator_traits<ForwardIterator1>::difference_type n
)
{
return current.first == last1 ? current
: n == 1 ? sprout::detail::find_end_impl_check(
current, last1,
sprout::detail::search_one(current.first, last1, first2, last2, pred)
)
: sprout::detail::find_end_impl_1(
sprout::detail::find_end_impl_1(
current,
last1, first2, last2, pred, n / 2
),
last1, first2, last2, pred, n - n / 2
)
;
}
template<typename ForwardIterator1, typename ForwardIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR sprout::pair<ForwardIterator1, ForwardIterator1>
find_end_impl(
sprout::pair<ForwardIterator1, ForwardIterator1> const& current,
ForwardIterator1 last1, ForwardIterator2 first2, ForwardIterator2 last2, BinaryPredicate pred,
typename std::iterator_traits<ForwardIterator1>::difference_type n
)
{
return current.first == last1 ? current
: sprout::detail::find_end_impl(
sprout::detail::find_end_impl_1(
current,
last1, first2, last2, pred, n
),
last1, first2, last2, pred, n * 2
)
;
}
template<typename ForwardIterator1, typename ForwardIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR ForwardIterator1
find_end(
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred,
std::forward_iterator_tag*
)
{
typedef sprout::pair<ForwardIterator1, ForwardIterator1> type;
return sprout::detail::find_end_impl(type(first1, last1), last1, first2, last2, pred, 1).second;
}
} // namespace detail
// 25.2.6 Find end
//
// recursion depth:
// O(log(N1+N2))
//
template<typename ForwardIterator1, typename ForwardIterator2, typename BinaryPredicate>
inline SPROUT_CONSTEXPR ForwardIterator1
find_end(
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2,
BinaryPredicate pred
)
{
typedef typename sprout::common_iterator_category<ForwardIterator1, ForwardIterator2>::type* category;
return first1 == last1 || first2 == last2 ? last1 : sprout::detail::find_end(first1, last1, first2, last2, pred, category());
}
template<typename ForwardIterator1, typename ForwardIterator2>
inline SPROUT_CONSTEXPR ForwardIterator1
find_end(
ForwardIterator1 first1, ForwardIterator1 last1,
ForwardIterator2 first2, ForwardIterator2 last2
)
{
return sprout::find_end(first1, last1, first2, last2, sprout::equal_to<>());
}
} // namespace sprout
#endif // #ifndef SPROUT_ALGORITHM_FIND_END_HPP