void merge( std::unordered_set<Key, H2, P2, Allocator>&& source ); (2) (since C++17) template< class H2, class P2 > void merge( std::unordered_multiset<Key, H2, P2, Allocator>& source ); (3) (since C++17) tem
unordered_set<string> first1;unordered_set<string>first2( {"one","two","three"} );unordered_set<string>first3( {"red","green","blue"} );unordered_set<string>first4( first2 );unordered_set<string>first5( cmerge(first4,first3) );unordered_set<string>first6( first5.begin(), first...
unordered_set is 是含有 Key 类型唯一对象集合的关联容器。搜索、插入和移除拥有平均常数时间复杂度。 在内部,元素并不以任何特别顺序排序,而是组织进桶中。元素被放进哪个桶完全依赖其值的哈希。这允许对单独元素的快速访问,因为哈希一旦确定,就准确指代元素被放入的桶。
merge (C++17) splices nodes from another container (public member function) Lookup count returns the number of elements matching specific key (public member function) find finds element with specific key (public member function) contains (C++20) ...
unordered_set::merge (C++17) unordered_set::insert unordered_set::insert_range (C++23) unordered_set::emplace unordered_set::emplace_hint Lookup unordered_set::count unordered_set::find unordered_set::contains (C++20) unordered_set::equal_range Bucket interface unordered_set::begin(size_type)...
EmplaceOrMerge。c++ unordered-set 2个回答 1投票 不,libstdc++ 不执行此优化。struct A { A() = default; A(A&&) { std::format_to(std::ostreambuf_iterator<char>(std::cout), "A(A&&)\n"); } bool operator==(A const&) const = default; }; template<> struct std::hash<A> { std...
void merge( std::unordered_multiset<Key, H2, P2, Allocator>&& source ); (4) (C++17 起) 试图提取(“接合”) source 中每个元素,并用 *this 的散列函数与键相等谓词插入到 *this。若 *this 中有元素,其键等价于来自 source 中元素的键,则不从 source 提取该元素。 不复制或移动元素,只会重指向...
merge (C++17) 从另一容器接合结点 (公开成员函数) 查找 count 返回匹配特定键的元素数量 (公开成员函数) find 寻找带有特定键的元素 (公开成员函数) contains (C++20) 检查容器是否含有带特定键的元素 (公开成员函数) equal_range 返回匹配特定键的元素范围 ...
unordered_set::merge (C++17) unordered_set::insert unordered_set::insert_range (C++23) unordered_set::emplace unordered_set::emplace_hint Lookup unordered_set::count unordered_set::find unordered_set::contains (C++20) unordered_set::equal_range Bucket interface unordered_set::begin(size_type)...
<cpp |container |unordered set C++ voidreserve(size_type count); (since C++11) Sets the number of buckets to the number needed to accommodate at leastcountelements without exceeding maximum load factor and rehashes the container, i.e. puts the elements into appropriate buckets considering...