[multimap.cons]

# 23 Containers library [[containers]](./#containers)

## 23.4 Associative containers [[associative]](associative#multimap.cons)

### 23.4.4 Class template multimap [[multimap]](multimap#cons)

#### 23.4.4.2 Constructors [multimap.cons]

[ð](#lib:multimap,constructor)

`constexpr explicit multimap(const Compare& comp, const Allocator& = Allocator());
`

[1](#1)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L12459)

*Effects*: Constructs an emptymultimap using the specified comparison object and allocator[.](#1.sentence-1)

[2](#2)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L12465)

*Complexity*: Constant[.](#2.sentence-1)

[ð](#lib:multimap,constructor_)

`template<class InputIterator>
  constexpr multimap(InputIterator first, InputIterator last,
                     const Compare& comp = Compare(), const Allocator& = Allocator());
`

[3](#3)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L12478)

*Effects*: Constructs an emptymultimap using the specified comparison object and allocator,
and inserts elements from the range
[first, last)[.](#3.sentence-1)

[4](#4)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L12486)

*Complexity*: Linear in N if the range
[first, last)
is already sorted with respect to comp and otherwise NlogN,
where N islast - first[.](#4.sentence-1)

[ð](#lib:multimap,constructor__)

`template<[container-compatible-range](container.intro.reqmts#concept:container-compatible-range "23.2.2.1 Introduction [container.intro.reqmts]")<value_type> R>
  constexpr multimap(from_range_t, R&& rg,
                     const Compare& comp = Compare(), const Allocator& = Allocator());
`

[5](#5)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L12504)

*Effects*: Constructs an empty multimap using the specified comparison object and allocator, and
inserts elements from the range rg[.](#5.sentence-1)

[6](#6)

[#](http://github.com/Eelis/draft/tree/9adde4bc1c62ec234483e63ea3b70a59724c745a/source/containers.tex#L12510)

*Complexity*: Linear in N if rg is already sorted with respect to comp and
otherwise NlogN, where N is ranges​::​distance(rg)[.](#6.sentence-1)
