3.0 KiB
[unord.multimap.cnstr]
23 Containers library [containers]
23.5 Unordered associative containers [unord]
23.5.4 Class template unordered_multimap [unord.multimap]
23.5.4.2 Constructors [unord.multimap.cnstr]
constexpr unordered_multimap() : unordered_multimap(size_type(see below)) { } constexpr explicit unordered_multimap(size_type n, const hasher& hf = hasher(), const key_equal& eql = key_equal(), const allocator_type& a = allocator_type());
Effects: Constructs an empty unordered_multimap using the specified hash function, key equality predicate, and allocator, and using at least n buckets.
For the default constructor, the number of buckets is implementation-defined.
max_load_factor() returns 1.0.
Complexity: Constant.
template<class InputIterator> constexpr unordered_multimap(InputIterator f, InputIterator l, size_type n = see below, const hasher& hf = hasher(), const key_equal& eql = key_equal(), const allocator_type& a = allocator_type()); template<[container-compatible-range](container.intro.reqmts#concept:container-compatible-range "23.2.2.1 Introduction [container.intro.reqmts]")<value_type> R> constexpr unordered_multimap(from_range_t, R&& rg, size_type n = see below, const hasher& hf = hasher(), const key_equal& eql = key_equal(), const allocator_type& a = allocator_type()); constexpr unordered_multimap(initializer_list<value_type> il, size_type n = see below, const hasher& hf = hasher(), const key_equal& eql = key_equal(), const allocator_type& a = allocator_type());
Effects: Constructs an empty unordered_multimap using the specified hash function, key equality predicate, and allocator, and using at least n buckets.
If n is not provided, the number of buckets is implementation-defined.
Then inserts elements from the range [f, l), rg, or il, respectively.
max_load_factor() returns 1.0.
Complexity: Average case linear, worst case quadratic.