__cpp_lib_constexpr_unordered_set202502L(C++26)constexprstd::unordered_set Example Run this code #include <iostream>#include <unordered_set>voidprint(constauto&set){for(constauto&elem:set)std::cout<<elem<<' ';st
以unordered_set为例,首先在cppreference中查看其模板定义: 可以看到Hash类默认是std::hash<Key,KeyEqual类似,本文将Hash以函数对象写出,将KeyEqual以lambda写出。 class hashvec{ public: size_t operator()(const vector<int> & vec) const { return hash<int>()(vec[0]) + hash<int>()(vec[1]) + h...
cppreference.com Page Discussion std::unordered_set<Key,Hash,KeyEqual,Allocator>::findC++ Containers library std::unordered_set iterator find( const Key& key ); (1) (since C++11) (constexpr since C++26) const_iterator find( const Key& key ) const; (2) (since C++11) (constexpr since...
cppreference.com Create account Page Discussion Standard revision: View Edit History std::unordered_set<Key,Hash,KeyEqual,Allocator>::containsC++ Containers library std::unordered_set bool contains( const Key& key ) const; (1) (since C++20) template< class K > bool contains( const K& x ...
From cppreference.com < cpp | container | unordered set C++ Compiler support Freestanding and hosted Language Standard library Standard library headers Named requirements Feature test macros (C++20) Language support library Concepts library (C++20) Metaprogramming library (C++11) Diagnostics librar...
你想做的事情可以通过std::unodered_set::extract完成。cppreference的例子：
cppreference 中给出了关于迭代器有效性的表格。我们还是以MSVC2017的实现作为说明。 OperationsInvalidated All read only operations, swap, std::swap Never clear, rehash, reserve, operator== Always insert, emplace, emplace_hint Only if causes rehash erase Only to the element erased 在MSVC2017中返回的...
SO作为由CPPReference.com配备C ++的初学者,我去了我拥有的 std::queue<std::unordered_set<PointUV, pointUVHash>> frontierPointsUV{};,我将其包括在下面的附录中。我的问题是 这是满足上述2个要求的明智方式? 我如何检查集合会员资格?我已经尝试了 typedef std::pair<int, int> PointUV;以固定会员资格...
问无法从cppreference.com编译unordered_set contains函数EN使用mysql中的concat()函数进行字符串拼接_mysql...
而如果是unordered 泛型容器,则需要传入hash函 数,现在让我们使用unordered_set为例子,下面是 定义 https://zh.cppreference.com/w/cpp/container/uno rdered set template< class Key, class Hash = std::hash<Key>, class KeyEqual = std::equal_to<Key>, ...