27 Algorithms library [algorithms]

27.6 Non-modifying sequence operations [alg.nonmodifying]

27.6.4 Contains [alg.contains]

```template<input_iterator I, sentinel_for<I> S, class Proj = identity, class T = projected_value_t<I, Proj>> requires indirect_binary_predicate<ranges::equal_to, projected<I, Proj>, const T*> constexpr bool ranges::contains(I first, S last, const T& value, Proj proj = {}); template<input_range R, class Proj = identity, class T = projected_value_t<iterator_t<R>, Proj>> requires indirect_binary_predicate<ranges::equal_to, projected<iterator_t<R>, Proj>, const T*> constexpr bool ranges::contains(R&& r, const T& value, Proj proj = {}); ```
Returns: ranges​::​find(std​::​move(first), last, value, proj) != last.
```template<forward_iterator I1, sentinel_for<I1> S1, forward_iterator I2, sentinel_for<I2> S2, class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity> requires indirectly_comparable<I1, I2, Pred, Proj1, Proj2> constexpr bool ranges::contains_subrange(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); template<forward_range R1, forward_range R2, class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity> requires indirectly_comparable<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2> constexpr bool ranges::contains_subrange(R1&& r1, R2&& r2, Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {}); ```
Returns: first2 == last2 || !ranges​::​search(first1, last1, first2, last2, pred, proj1, proj2).empty().