1/*
2 Copyright (c) T. Zachary Laine 2018.
3
4 Distributed under the Boost Software License, Version 1.0. (See accompanying
5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6*/
7#ifndef BOOST_ALGORITHM_FIND_BACKWARD_HPP
8#define BOOST_ALGORITHM_FIND_BACKWARD_HPP
9
10#include <utility>
11
12#include <boost/config.hpp>
13#include <boost/range/begin.hpp>
14#include <boost/range/end.hpp>
15
16namespace boost { namespace algorithm {
17
18template<typename BidiIter, typename T>
19BOOST_CXX14_CONSTEXPR
20BidiIter find_backward(BidiIter first, BidiIter last, const T & x)
21{
22 BidiIter it = last;
23 while (it != first) {
24 if (*--it == x)
25 return it;
26 }
27 return last;
28}
29
30template<typename Range, typename T>
31BOOST_CXX14_CONSTEXPR
32typename boost::range_iterator<Range>::type find_backward(Range & range, const T & x)
33{
34 return ::boost::algorithm::find_backward(boost::begin(range), boost::end(range), x);
35}
36
37template<typename BidiIter, typename T>
38BOOST_CXX14_CONSTEXPR
39BidiIter find_not_backward(BidiIter first, BidiIter last, const T & x)
40{
41 BidiIter it = last;
42 while (it != first) {
43 if (*--it != x)
44 return it;
45 }
46 return last;
47}
48
49template<typename Range, typename T>
50BOOST_CXX14_CONSTEXPR
51typename boost::range_iterator<Range>::type find_not_backward(Range & range, const T & x)
52{
53 return ::boost::algorithm::find_not_backward(boost::begin(range), boost::end(range), x);
54}
55
56template<typename BidiIter, typename Pred>
57BOOST_CXX14_CONSTEXPR
58BidiIter find_if_backward(BidiIter first, BidiIter last, Pred p)
59{
60 BidiIter it = last;
61 while (it != first) {
62 if (p(*--it))
63 return it;
64 }
65 return last;
66}
67
68template<typename Range, typename Pred>
69BOOST_CXX14_CONSTEXPR
70typename boost::range_iterator<Range>::type find_if_backward(Range & range, Pred p)
71{
72 return ::boost::algorithm::find_if_backward(boost::begin(range), boost::end(range), p);
73}
74
75template<typename BidiIter, typename Pred>
76BOOST_CXX14_CONSTEXPR
77BidiIter find_if_not_backward(BidiIter first, BidiIter last, Pred p)
78{
79 BidiIter it = last;
80 while (it != first) {
81 if (!p(*--it))
82 return it;
83 }
84 return last;
85}
86
87template<typename Range, typename Pred>
88BOOST_CXX14_CONSTEXPR
89typename boost::range_iterator<Range>::type find_if_not_backward(Range & range, Pred p)
90{
91 return ::boost::algorithm::find_if_not_backward(boost::begin(range), boost::end(range), p);
92}
93
94}} // namespace boost and algorithm
95
96#endif // BOOST_ALGORITHM_FIND_BACKWARD_HPP
97

source code of boost/libs/algorithm/include/boost/algorithm/find_backward.hpp