C++ std::set<,> operator怎么用 std::set 不重复key 默认less排序 STL中的关联容器: std::set template< class Key, class Compare =std::less<Key>, class Allocator =std::allocator<Key> > class set; 1. 2. 3. 4. 5. std::set是关联容器,含有Key类型对象的已排序集。 它的key就是value,valu...
C++ std::set operator <= find失效 erase失效 解决方案 #include <iostream> #include <set> using namespace std; class stru{ public: stru(int a, int b): x(a), y(b){} int x; int y; }; bool operator<(const stru& a, const stru& b) //比较的是x的值 { return a.x <= b.x;...
#include <algorithm>#include <iomanip>#include <iostream>#include <iterator>#include <set>#include <string_view>template<typenameT>std::ostream&operator<<(std::ostream&out,conststd::set<T>&set){if(set.empty())returnout<<"{}";out<<"{ "<<*set.begin();std::for_each(std::next(set....
使用自定义比较函数:std::set 默认使用operator<进行元素的比较,如果元素是自定义类型,可以重载operator<或者提供自定义比较函数,以提高比较的效率。 使用emplace()替代insert():emplace()函数可以直接构造元素并插入set中,避免了额外的复制操作。 使用reserve()预留空间:如果能提前知道set的大小,可以使用reserve()函数提...
1#include <iostream>2#include <set>3usingnamespacestd;4structsong5{6intm_id;7intm_hot;8song(intid,inthot)9{1011this->m_id =id;12this->m_hot =hot;13}14/*15bool operator<(const struct song & right)const //重载<运算符16{17if(this->m_id == right.m_id) //根据id去重18return...
这个比较函数需要接受两个set中元素类型的参数,并返回一个布尔值,指示第一个参数是否应该被视为小于第二个参数。 #include<set>#include<iostream>// 自定义比较函数structCompare{booloperator()(constinta,constintb)const{returna>b;// 降序排序}};
#include <algorithm>#include <iomanip>#include <iostream>#include <iterator>#include <set>#include <string_view>template<typenameT>std::ostream&operator<<(std::ostream&out,conststd::set<T>&set){if(set.empty())returnout<<"{}";out<<"{ "<<*set.begin();std::for_each(std::next(set....
1#include <iostream>2#include <set>3usingnamespacestd;4structsong5{6intm_id;7intm_hot;8song(intid,inthot)9{1011this->m_id =id;12this->m_hot =hot;13}14/*15bool operator<(const struct song & right)const //重载<运算符16{17if(this->m_id == right.m_id) //根据id去重18return...
operator= assigns values to the container (public member function) get_allocator returns the associated allocator (public member function) Iterators begincbegin (C++11) returns an iterator to the beginning (public member function) endcend (C++11) ...
std::set<Key,Compare,Allocator>::operator= std::set<Key,Compare,Allocator>::empty std::multiset std::multimap std::unordered_set std::unordered_multiset std::unordered_multimap std::stack std::queue std::vector<bool> 结点把柄 (C++17) 注释 迭代器库 范围库 (C++20) 算法库 数值库 输入/输...