Function contains

unittests/catch.hpp:2535–2542

            }
            template <typename InputIterator, typename T>
            bool contains(InputIterator first, InputIterator last, T const& item) {
                for (; first != last; ++first) {
                    if (*first == item) {
                        return true;
                    }
                }
                return false;
            }
        }

        template<typename T>