std::unordered_map

 

C++

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Regular expressions library (C++11)

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Containers library

array (C++11)

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vector

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forward_list (C++11)

list

set

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unordered_set (C++11)

unordered_multiset (C++11)

unordered_map (C++11)

unordered_multimap (C++11)

stack

queue

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std::unordered_map

Member functions

unordered_map::unordered_map

unordered_map::~unordered_map

unordered_map::operator=

unordered_map::get_allocator

Iterators

unordered_map::begin unordered_map::cbegin

unordered_map::end unordered_map::cend

Capacity

unordered_map::erase

unordered_map::size

unordered_map::max_size

Modifiers

unordered_map::clear

unordered_map::insert

unordered_map::emplace

unordered_map::emplace_hint

unordered_map::erase

unordered_map::swap

Lookup

unordered_map::count

unordered_map::find

unordered_map::equal_range

Bucket interface

unordered_map::begin2

unordered_map::end2

unordered_map::bucket_count

unordered_map::max_bucket_count

unordered_map::bucket_size

unordered_map::bucket

Hash policy

unordered_map::load_factor

unordered_map::max_load_factor

unordered_map::rehash

unordered_map::reserve

Observers

unordered_map::hash_function

unordered_map::key_eq

 

Defined in header <unordered_map>
template<     class Key,     class T,     class Hash = std::hash<Key>,     class KeyEqual = std::equal_to<Key>,     class Allocator = std::allocator< std::pair<const Key, T> > > class unordered_map;		(since C++11)

Unordered map is an associative container that contains key-value pairs with unique keys. Search, insertion, and removal have average constant-time complexity.

std::unordered_map meets the requirements of Container, AllocatorAwareContainer, UnorderedAssociativeContainer.

Member types

Template:cpp/container/dcl list key typeTemplate:cpp/container/dcl list mapped typeTemplate:cpp/container/dcl list value typeTemplate:cpp/container/dcl list size typeTemplate:cpp/container/dcl list difference typeTemplate:cpp/container/dcl list hasherTemplate:cpp/container/dcl list key equalTemplate:cpp/container/dcl list allocator typeTemplate:cpp/container/dcl list referenceTemplate:cpp/container/dcl list const referenceTemplate:cpp/container/dcl list pointerTemplate:cpp/container/dcl list const pointerTemplate:cpp/container/dcl list iteratorTemplate:cpp/container/dcl list const iteratorTemplate:cpp/container/dcl list local iteratorTemplate:cpp/container/dcl list const local iterator

Member type	Definition

Member functions

Template:cpp/container/dcl list constructorTemplate:cpp/container/dcl list destructorTemplate:cpp/container/dcl list operator=Template:cpp/container/dcl list get allocatorTemplate:cpp/container/dcl list beginTemplate:cpp/container/dcl list endTemplate:cpp/container/dcl list emptyTemplate:cpp/container/dcl list sizeTemplate:cpp/container/dcl list max sizeTemplate:cpp/container/dcl list clearTemplate:cpp/container/dcl list insertTemplate:cpp/container/dcl list emplaceTemplate:cpp/container/dcl list emplace hintTemplate:cpp/container/dcl list eraseTemplate:cpp/container/dcl list swapTemplate:cpp/container/dcl list atTemplate:cpp/container/dcl list operator atTemplate:cpp/container/dcl list countTemplate:cpp/container/dcl list findTemplate:cpp/container/dcl list equal rangeTemplate:cpp/container/dcl list begin(int)Template:cpp/container/dcl list end(int)Template:cpp/container/dcl list bucket countTemplate:cpp/container/dcl list max bucket countTemplate:cpp/container/dcl list bucket sizeTemplate:cpp/container/dcl list bucketTemplate:cpp/container/dcl list load factorTemplate:cpp/container/dcl list max load factorTemplate:cpp/container/dcl list rehashTemplate:cpp/container/dcl list reserveTemplate:cpp/container/dcl list hash functionTemplate:cpp/container/dcl list key eq

Iterators

Capacity

Modifiers

Lookup

Bucket interface

Hash policy

Observers

Non-member functions

Template:cpp/container/dcl list operator cmp unordTemplate:cpp/container/dcl list swap2