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
8};// creates a set of intsprint(mySet);mySet.insert(5);// puts an element 5 in the setprint(mySet);if(autoiter=mySet.find(5);iter!=mySet.end())mySet.erase(iter);// removes an element pointed to by iterprint(mySet);mySet.erase(7);// removes an element 7print(mySet);...
Time Complexity Average case: Linear in the number of elements removed for version 1 and version 2. Worst case: Linear in the container size.. Example: In the example below, the unordered_set::erase function is used to delete a single element from uSet. #include <iostream> #include <un...
C++11 unordered_set::emplace C++11 unordered_set::emplace_hint C++11 unordered_set::empty C++11 unordered_set::end C++11 unordered_set::equal_range C++11 unordered_set::erase C++11 unordered_set::find C++11 unordered_set::get_allocator C++11 unordered_set::hash_function C++11...
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...
// swap (unordered_set specialization)#include <iostream>#include <string>#include <unordered_set>intmain () { std::unordered_set<std::string> first = {"Metropolis","Solaris","Westworld"}, second = {"Avatar","Inception"}; swap(first,second); std::cout <<"first:";for(conststd::strin...
unordered_set Vs. unordered_multiset unordered_set: A container that stores unique elements only, no duplicates are allowed. unordered_multiset: A container that allows multiple occurrences (duplicates) of the same element. Average Time Complexity of unordered_multiset unordered_multiset is implemented ...
unordered_map::erase unordered_map::swap unordered_map::extract (C++17) unordered_map::merge (C++17) unordered_map::insert unordered_map::insert_range (C++23) unordered_map::insert_or_assign (C++17) unordered_map::emplace unordered_map::emplace_hint unordered_map::try_emplace (C++17) Loo...
unordered_map are not sorted in any particular order with respect to either their key or mapped values, but organized into buckets(桶) depending on their hash values to allow for fast access to individual elements directly by their key values (with a constant average time complexity on average...
stdunordered_mapumcout<<"Unordered map contains following elements before erase operation"<<endl;for(autoit=um.begin();it!=um.end();++it)cout<<it->first<<" = "<<it->second<<endl;um.erase(um.begin());cout<<endl;cout<<"Unordered map contains following elements after erase operation"<...