std:: unordered_map - cppreference.com
Apr 26, 2025 · std::unordered_map is an associative container that contains key-value pairs with unique keys. Search, insertion, and removal of elements have average constant-time complexity.
std:: unordered_set - cppreference.com
Apr 26, 2025 · std::unordered_set is an associative container that contains a set of unique objects of type Key. Search, insertion, and removal have average constant-time complexity.
std::unordered_map<Key,T,Hash,KeyEqual,Allocator>:: …
Nov 29, 2021 · Define a const == operator for the class/struct and specialize std::hash// structure in the std namespacestd::unordered_map<std::string>={{(1)"One"}{2"Two"}{3"Three"}};// …
Standard library header <unordered_set> (C++11) - Reference
Nov 27, 2023 · Classes unordered_set (C++11) collection of unique keys, hashed by keys (class template) [edit] unordered_multiset (C++11) collection of keys, hashed by keys (class …
std::unordered_set<Key,Hash,KeyEqual,Allocator>:: insert
May 9, 2025 · The value_type must be EmplaceConstructible into unordered_set from std::forward<K>(obj). This overload participates in overload resolution only if Hash and …
std::unordered_set<Key,Hash,KeyEqual,Allocator>:: find
Nov 29, 2021 · Simple comparison demo: Found 2 Heterogeneous lookup for unordered containers (transparent hashing): std::size_t string_hash::operator () (const char*) const true …
std::unordered_map<Key,T,Hash,KeyEqual,Allocator>:: merge
Nov 29, 2021 · unordered_map::merge (C++17) unordered_map::insert unordered_map::insert_range (C++23) unordered_map::insert_or_assign (C++17) …
std::unordered_map<Key,T,Hash,KeyEqual,Allocator>:: erase
Dec 4, 2021 · unordered_map::merge (C++17) unordered_map::insert unordered_map::insert_range (C++23) unordered_map::insert_or_assign (C++17) …
Standard library header <unordered_map> (C++11) - Reference
Nov 27, 2023 · unordered_map (initializer_list <pair <Key, T>>, Allocator) -> unordered_map <Key, T, hash <Key>, equal_to <Key>, Allocator>; template<class Key, class T, class Hash, …
std::unordered_map<Key,T,Hash,KeyEqual,Allocator>:: emplace
Dec 4, 2021 · unordered_map::merge (C++17) unordered_map::insert unordered_map::insert_range (C++23) unordered_map::insert_or_assign (C++17) …