mirror/Sprout
1
0
Fork 0
mirror of https://github.com/bolero-MURAKAMI/Sprout.git synced 2025-07-04 14:14:09 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

fix recursion depth: min_element, max_element, minmax_element

Browse source
This commit is contained in:
bolero-MURAKAMI 2012-12-16 21:46:16 +09:00
parent 86f68671a1
commit 1c085cb707
10 changed files with 539 additions and 17 deletions
Download patch file Download diff file Expand all files Collapse all files

71
sprout/algorithm/max_element.hpp
View file

@ -4,30 +4,89 @@
#include <iterator>
#include <sprout/config.hpp>
#include <sprout/iterator/operation.hpp>
#include HDR_ITERATOR_SSCRISK_CEL_OR_SPROUT
#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
namespace sprout {
// Copyright (C) 2011 RiSK (sscrisk)
namespace detail {
template<typename InputIterator, typename Compare>
inline SPROUT_CONSTEXPR InputIterator
iter_max(InputIterator a, InputIterator b, Compare comp) {
return comp(*a, *b) ? b : a;
}
template<typename RandomAccessIterator, typename Compare>
inline SPROUT_CONSTEXPR RandomAccessIterator
max_element_impl_ra(
RandomAccessIterator first, RandomAccessIterator last, Compare comp,
typename std::iterator_traits<RandomAccessIterator>::difference_type pivot
)
{
return pivot == 0 ? first
: sprout::detail::iter_max(
sprout::detail::max_element_impl_ra(
first, sprout::next(first, pivot), comp,
pivot / 2
),
sprout::detail::max_element_impl_ra(
sprout::next(first, pivot), last, comp,
(NS_SSCRISK_CEL_OR_SPROUT::distance(first, last) - pivot) / 2
),
comp
)
;
}
template<typename RandomAccessIterator, typename Compare>
inline SPROUT_CONSTEXPR RandomAccessIterator
max_element(
RandomAccessIterator first, RandomAccessIterator last, Compare comp,
std::random_access_iterator_tag*
)
{
return first == last ? last
: sprout::detail::max_element_impl_ra(
first, last, comp,
NS_SSCRISK_CEL_OR_SPROUT::distance(first, last) / 2
)
;
}
// Copyright (C) 2011 RiSK (sscrisk)
template<typename ForwardIterator, typename Compare>
inline SPROUT_CONSTEXPR ForwardIterator
max_element_impl(
ForwardIterator first, ForwardIterator last, Compare comp,
ForwardIterator max
ForwardIterator found
)
{
return first == last ? max
: sprout::detail::max_element_impl(sprout::next(first), last, comp, comp(*max, *first) ? first : max)
return first == last ? found
: sprout::detail::max_element_impl(sprout::next(first), last, comp, sprout::detail::iter_max(found, first, comp))
;
}
template<typename ForwardIterator, typename Compare>
inline SPROUT_CONSTEXPR ForwardIterator
max_element(
ForwardIterator first, ForwardIterator last, Compare comp,
void*
)
{
return first == last ? last
: sprout::detail::max_element_impl(sprout::next(first), last, comp, first)
;
}
} // namespace detail
// 25.4.7 Minimum and maximum
//
// recursion depth:
// [first, last) is RandomAccessIterator -> O(log N)
// otherwise -> O(N)
//
template<typename ForwardIterator, typename Compare>
inline SPROUT_CONSTEXPR ForwardIterator
max_element(ForwardIterator first, ForwardIterator last, Compare comp) {
return sprout::detail::max_element_impl(first, last, comp, first);
typedef typename std::iterator_traits<ForwardIterator>::iterator_category* category;
return sprout::detail::max_element(first, last, comp, category());
}
template<typename ForwardIterator>