C++ unordered_set 源于https://en.cppreference.com/w/cpp/container/unordered_set的说明 Search, insertion, and removal have average constant-time complexity. Internally, the elements are not sorted in any particular order, bu...unordered_set使用介绍 unordered_set C++ 11,新的关联容器:unordered_...
std::unordered_setis an associative container that contains a set of unique objects of typeKey. Search, insertion, and removal have average constant-time complexity. Internally, the elements are not sorted in any particular order, but organized into buckets. Which bucket an element is placed into...
unordered_set 只包含键,没有值。没有从键到值的映射,因此不需要 operator[]。 unordered_map 将键映射到值。 您可以使用 --- 中的各种 find unordered_set 来定位事物。 原文由 1201ProgramAlarm 发布,翻译遵循 CC BY-SA 3.0 许可协议有用 回复 撰写回答 你尚未登录,登录后可以 和开发者交流问题的细节 ...
Internally, the elements in the unordered_set are not sorted in any particular order, but organized into buckets depending on their hash values to allow for fast access to individual elements directly by their values (with a constant average time complexity on average). unordered_set containers ar...
Complexity Linear on size (destructors). Iterator validity All iterators, pointers and references are invalidated. See also unordered_set::erase Erase elements (public member function) unordered_set::empty Test whether container is empty (public member function)Home...
在C++中,可以使用std::pair作为哈希表(在C++中通常指的是std::unordered_map或std::unordered_set)的键值。然而,要确保键值可以被哈希化(也就是要为这个键值类型提供一个哈希函数)并且能够被比较(也就是要为这个键值类型提供一个等于运算符)。 关于不能作为键值的类型,那些没有默认的哈希函数或者无法用==运算符...
myset has hat myset has no sunglasses myset has suit myset has no t-shirt Complexity Average case: constant. Worst case: linear in container size.Iterator validity No changes.See also unordered_set::find Get iterator to element (public member function) unordered_set::size Return container ...
unordered_set<int>example{1,2,-10};std::cout<<"Simple comparison demo:\n"<<std::boolalpha;if(autosearch=example.find(2);search!=example.end())std::cout<<"Found "<<*search<<'\n';elsestd::cout<<"Not found\n";std::unordered_set<std::string, string_hash,std::equal_to<>>set{...
unordered_set 只包含键,没有值。没有从键到值的映射,因此不需要 operator[]。 unordered_map 将键映射到值。 您可以使用 --- 中的各种 find unordered_set 来定位事物。 原文由 1201ProgramAlarm 发布,翻译遵循 CC BY-SA 3.0 许可协议 有用 回复 ...
The best case and the average case complexity for all the operations in an unordered_map is O(1). While in the worst case, the time complexity for all the operations in an unordered_map is O(n). The difference between an unordered_map and an unordered_set is that an unordered_map sto...