[alg.ends.with]

# 26 Algorithms library [[algorithms]](./#algorithms)

## 26.6 Non-modifying sequence operations [[alg.nonmodifying]](alg.nonmodifying#alg.ends.with)

### 26.6.17 Ends with [alg.ends.with]

[🔗](#lib:ends_with)

`template<[input_iterator](iterator.concept.input#concept:input_iterator "24.3.4.9 Concept input_­iterator [iterator.concept.input]") I1, [sentinel_for](iterator.concept.sentinel#concept:sentinel_for "24.3.4.7 Concept sentinel_­for [iterator.concept.sentinel]")<I1> S1, [input_iterator](iterator.concept.input#concept:input_iterator "24.3.4.9 Concept input_­iterator [iterator.concept.input]") I2, [sentinel_for](iterator.concept.sentinel#concept:sentinel_for "24.3.4.7 Concept sentinel_­for [iterator.concept.sentinel]")<I2> S2,
         class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
  requires ([forward_iterator](iterator.concept.forward#concept:forward_iterator "24.3.4.11 Concept forward_­iterator [iterator.concept.forward]")<I1> || [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<S1, I1>) &&
           ([forward_iterator](iterator.concept.forward#concept:forward_iterator "24.3.4.11 Concept forward_­iterator [iterator.concept.forward]")<I2> || [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<S2, I2>) &&
           [indirectly_comparable](alg.req.ind.cmp#concept:indirectly_comparable "24.3.7.5 Concept indirectly_­comparable [alg.req.ind.cmp]")<I1, I2, Pred, Proj1, Proj2>
  constexpr bool ranges::ends_with(I1 first1, S1 last1, I2 first2, S2 last2, Pred pred = {},
                                   Proj1 proj1 = {}, Proj2 proj2 = {});
`

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6091)

Let N1 be last1 - first1 andN2 be last2 - first2[.](#1.sentence-1)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6095)

*Returns*: false if N1 < N2, otherwise:ranges::equal(std::move(first1) + (N1 - N2), last1, std::move(first2), last2,
 pred, proj1, proj2)

[🔗](#itemdecl:2)

`template<[execution-policy](algorithms.parallel.defns#concept:execution-policy "26.3.1 Preamble [algorithms.parallel.defns]") Ep, [random_access_iterator](iterator.concept.random.access#concept:random_access_iterator "24.3.4.13 Concept random_­access_­iterator [iterator.concept.random.access]") I1, [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<I1> S1,
         [random_access_iterator](iterator.concept.random.access#concept:random_access_iterator "24.3.4.13 Concept random_­access_­iterator [iterator.concept.random.access]") I2, [sized_sentinel_for](iterator.concept.sizedsentinel#concept:sized_sentinel_for "24.3.4.8 Concept sized_­sentinel_­for [iterator.concept.sizedsentinel]")<I2> S2,
         class Pred = ranges::equal_to, class Proj1 = identity, class Proj2 = identity>
  requires [indirectly_comparable](alg.req.ind.cmp#concept:indirectly_comparable "24.3.7.5 Concept indirectly_­comparable [alg.req.ind.cmp]")<I1, I2, Pred, Proj1, Proj2>
  bool ranges::ends_with(Ep&& exec, I1 first1, S1 last1, I2 first2, S2 last2,
                         Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
`

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6114)

Let N1 be last1 - first1 andN2 be last2 - first2[.](#3.sentence-1)

[4](#4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6118)

*Returns*: false if N1 < N2, otherwise:ranges::equal(std::forward<Ep>(exec), std::move(first1) + (N1 - N2), last1,
 std::move(first2), last2, pred, proj1, proj2)

[🔗](#itemdecl:3)

`template<[input_range](range.refinements#concept:input_range "25.4.6 Other range refinements [range.refinements]") R1, [input_range](range.refinements#concept:input_range "25.4.6 Other range refinements [range.refinements]") R2, class Pred = ranges::equal_to, class Proj1 = identity,
         class Proj2 = identity>
  requires ([forward_range](range.refinements#concept:forward_range "25.4.6 Other range refinements [range.refinements]")<R1> || [sized_range](range.sized#concept:sized_range "25.4.4 Sized ranges [range.sized]")<R1>) &&
           ([forward_range](range.refinements#concept:forward_range "25.4.6 Other range refinements [range.refinements]")<R2> || [sized_range](range.sized#concept:sized_range "25.4.4 Sized ranges [range.sized]")<R2>) &&
           [indirectly_comparable](alg.req.ind.cmp#concept:indirectly_comparable "24.3.7.5 Concept indirectly_­comparable [alg.req.ind.cmp]")<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
  constexpr bool ranges::ends_with(R1&& r1, R2&& r2, Pred pred = {},
                                   Proj1 proj1 = {}, Proj2 proj2 = {});
`

[5](#5)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6138)

Let N1 be ranges​::​distance(r1) andN2 be ranges​::​distance(r2)[.](#5.sentence-1)

[6](#6)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6142)

*Returns*: false if N1 < N2, otherwise:ranges::equal(views::drop(ranges::ref_view(r1), N1 - static_cast<decltype(N1)>(N2)),
 r2, pred, proj1, proj2)

[🔗](#itemdecl:4)

`template<[execution-policy](algorithms.parallel.defns#concept:execution-policy "26.3.1 Preamble [algorithms.parallel.defns]") Ep, [sized-random-access-range](range.refinements#concept:sized-random-access-range "25.4.6 Other range refinements [range.refinements]") R1,
         [sized-random-access-range](range.refinements#concept:sized-random-access-range "25.4.6 Other range refinements [range.refinements]") R2, class Pred = ranges::equal_to,
         class Proj1 = identity, class Proj2 = identity>
  requires [indirectly_comparable](alg.req.ind.cmp#concept:indirectly_comparable "24.3.7.5 Concept indirectly_­comparable [alg.req.ind.cmp]")<iterator_t<R1>, iterator_t<R2>, Pred, Proj1, Proj2>
  bool ranges::ends_with(Ep&& exec, R1&& r1, R2&& r2,
                         Pred pred = {}, Proj1 proj1 = {}, Proj2 proj2 = {});
`

[7](#7)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6161)

Let N1 be ranges​::​distance(r1) andN2 be ranges​::​distance(r2)[.](#7.sentence-1)

[8](#8)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/algorithms.tex#L6165)

*Returns*: false if N1 < N2, otherwise:ranges::equal(std::forward<Ep>(exec),
 views::drop(ranges::ref_view(r1), N1 - static_cast<decltype(N1)>(N2)),
 r2, pred, proj1, proj2)