Boost C++ Libraries

namespace boost {
  namespace algorithm {
    template<typename BidiIter, typename T> 
      BOOST_CXX14_CONSTEXPR BidiIter 
      find_backward(BidiIter first, BidiIter last, const T & x);
    template<typename Range, typename T> 
      BOOST_CXX14_CONSTEXPR boost::range_iterator< Range >::type 
      find_backward(Range & range, const T & x);
    template<typename BidiIter, typename T> 
      BOOST_CXX14_CONSTEXPR BidiIter 
      find_not_backward(BidiIter first, BidiIter last, const T & x);
    template<typename Range, typename T> 
      BOOST_CXX14_CONSTEXPR boost::range_iterator< Range >::type 
      find_not_backward(Range & range, const T & x);
    template<typename BidiIter, typename Pred> 
      BOOST_CXX14_CONSTEXPR BidiIter 
      find_if_backward(BidiIter first, BidiIter last, Pred p);
    template<typename Range, typename Pred> 
      BOOST_CXX14_CONSTEXPR boost::range_iterator< Range >::type 
      find_if_backward(Range & range, Pred p);
    template<typename BidiIter, typename Pred> 
      BOOST_CXX14_CONSTEXPR BidiIter 
      find_if_not_backward(BidiIter first, BidiIter last, Pred p);
    template<typename Range, typename Pred> 
      BOOST_CXX14_CONSTEXPR boost::range_iterator< Range >::type 
      find_if_not_backward(Range & range, Pred p);
  }
}