UnorderedAssociativeContainer

X::key_type

Key

?

?

compile time

X::mapped_type

T

std::unordered_map and std::unordered_multimap only

?

compile time

X::value_type

Key

std::unordered_set and std::unordered_multiset only. Erasable in X

?

compile time

X::value_type

std::pair<const Key, T>

std::unordered_map and std::unordered_multimap only. Erasable in X

?

compile time

X::hasher

Hash

Hash

?

compile time

X::key_equal

Pred

BinaryPredicate taking two arguments of type Key and expressing an equivalence relation.

?

compile time

X::local_iterator

An Iterator whose category and types are the same as X::iterator

?

Can be used to iterate through a single bucket

compile time

X::const_local_iterator

An Iterator whose category and types are the same as X::const_iterator

?

Can be used to iterate through a single bucket

compile time

X(n,hf,eq)

X

hasher and key_equal CopyConstructible

Constructs an empty container with at least n buckets, using the given hash function and equality predicate

linear in n

X(n,hf)

X

hasher CopyConstructible, key_equal DefaultConstructible

Constructs an empty container with at least n buckets, using the given hash function and key_equal() as equality predicate

linear in n

X(n,hf)

X

hasher and key_equal DefaultConstructible

Constructs an empty container with at least n buckets, using hasher() as hash function and key_equal() as equality predicate

linear in n

X()

X

hasher and key_equal DefaultConstructible

Constructs an empty container with an unspecified number of buckets, using hasher() as hash function and key_equal() as equality predicate

constant

X(i,j,n,hf,eq)

X

hasher and key_equal CopyConstructible, value_type EmplaceConstructible into X from *i

Constructs an empty container with at least n buckets, using the given hash function and equality predicate, and inserts elements from [i,j) into it.

average linear, worst quadratin (on the distance between i and j)

X(i,j,n,hf)

X

key_equal DefaultConstructible

As above, with eq=key_equal()

see above

X(i,j,n)

X

hasher DefaultConstructible

As above, with hf=hasher()

see above

X(i,j)

X

?

As above, with an unspecified number of buckets

see above

X(il)

X

?

X(il.begin(),il.end()

see above

X(il,n)

X

?

X(il.begin(),il.end(),n

see above

X(il,n,hf)

X

?

X(il.begin(),il.end(),n,hf

see above

X(il,n,hf,eq)

X

?

X(il.begin(),il.end(),n,hf,eq

see above

X(b)

X

?

Copy constructors, also copies the hash function, predicate and maximum load factor

average linear, worst quadratic (in b.size())

a = b

X&

?

Copy assignment, also copies the hash function, predicate and maximum load factor

average linear, worst quadratic (in b.size())

a = il

X&

value_type CopyAssignable and CopyInsertable into X

a = X(il)

see above

unordered_multiset (since C++11)

collection of keys, hashed by keys (class template)

unordered_map (since C++11)

collection of key-value pairs, hashed by keys, keys are unique (class template)

unordered_multimap (since C++11)

collection of key-value pairs, hashed by keys (class template)