mirror of
https://github.com/bolero-MURAKAMI/Sprout.git
synced 2024-12-25 21:35:41 +00:00
64 lines
2.2 KiB
C++
64 lines
2.2 KiB
C++
/*=============================================================================
|
|
Copyright (c) 2011-2014 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_CXX14_PREV_PERMUTATION_HPP
|
|
#define SPROUT_ALGORITHM_CXX14_PREV_PERMUTATION_HPP
|
|
|
|
#include <iterator>
|
|
#include <type_traits>
|
|
#include <sprout/config.hpp>
|
|
#include <sprout/algorithm/cxx14/reverse.hpp>
|
|
#include <sprout/utility/swap.hpp>
|
|
#include HDR_FUNCTIONAL_SSCRISK_CEL_OR_SPROUT
|
|
|
|
namespace sprout {
|
|
namespace detail {
|
|
template<typename Compare, typename BidirectionalIterator>
|
|
inline SPROUT_CXX14_CONSTEXPR bool
|
|
prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp) {
|
|
BidirectionalIterator i = last;
|
|
if (first == last || first == --i) {
|
|
return false;
|
|
}
|
|
while (true) {
|
|
BidirectionalIterator ip1 = i;
|
|
if (comp(*ip1, *--i)) {
|
|
BidirectionalIterator j = last;
|
|
while (!comp(*--j, *i))
|
|
;
|
|
sprout::swap(*i, *j);
|
|
sprout::reverse(ip1, last);
|
|
return true;
|
|
}
|
|
if (i == first) {
|
|
sprout::reverse(first, last);
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
} // namespace detail
|
|
//
|
|
// 25.4.9 Permutation generators
|
|
//
|
|
template<typename BidirectionalIterator, typename Compare>
|
|
inline SPROUT_CXX14_CONSTEXPR bool
|
|
prev_permutation(BidirectionalIterator first, BidirectionalIterator last, Compare comp) {
|
|
typedef typename std::add_lvalue_reference<Compare>::type compare_ref;
|
|
return sprout::detail::prev_permutation<compare_ref>(first, last, comp);
|
|
}
|
|
|
|
template<typename BidirectionalIterator>
|
|
inline SPROUT_CXX14_CONSTEXPR bool
|
|
prev_permutation(BidirectionalIterator first, BidirectionalIterator last) {
|
|
return sprout::prev_permutation(
|
|
first, last,
|
|
NS_SSCRISK_CEL_OR_SPROUT::less<typename std::iterator_traits<BidirectionalIterator>::value_type>()
|
|
);
|
|
}
|
|
} // namespace sprout
|
|
|
|
#endif // #ifndef SPROUT_ALGORITHM_CXX14_PREV_PERMUTATION_HPP
|