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Header <boost/algorithm/cxx11/one_of.hpp>

Test ranges to see if only one element matches a value or predicate.

Marshall Clow

namespace boost {
  namespace algorithm {
    template<typename InputIterator, typename Predicate>
      bool one_of(InputIterator, InputIterator, Predicate);
    template<typename Range, typename Predicate>
      bool one_of(const Range &, Predicate);
    template<typename InputIterator, typename V>
      bool one_of_equal(InputIterator, InputIterator, const V &);
    template<typename Range, typename V>
      bool one_of_equal(const Range &, const V &);