std::map是排序的关联容器,其中包含具有唯一键(key)的“键/值(key/value)”对。 头文件为<map>。 2、名词定义: 键(key):关键字,在map中是唯一的,可以使用int、string等基本类型。 值(value):值,可以是基本类型,也可以是向量、类等类型。 容器:可以理解成包含一个或多个“键/值”对的map变量。 元素:...
key compare function struct ModCmp { bool operator()(int lhs, int rhs) const { return (lhs % 97) < (rhs % 97); } }; int main() { std::map<int, char, ModCmp> cont; cont = {{1, 'a'}, {2, 'b'}, {3, 'c'}, {4, 'd'}, {5, 'e'}}; auto comp_func = cont....
mapStudent.insert(map<int, string>::value_type (1, "student_one")); mapStudent.insert(map<int, string>::value_type (2, "student_two")); mapStudent.insert(map<int, string>::value_type (3, "student_three")); map<int, string>::iterator iter; for(iter = mapStudent.begin(); iter...
// map::key_comp#include <iostream>#include <map>intmain () { std::map<char,int> mymap; std::map<char,int>::key_compare mycomp = mymap.key_comp(); mymap['a']=100; mymap['b']=200; mymap['c']=300; std::cout <<"mymap contains:\n";charhighest = mymap.rbegin()->fi...
std::map<Key,T,Compare,Allocator>::value_comp From cppreference.com <cpp |container |map Returns a function object that compares objects of typestd::map::value_type(key-value pairs) by usingkey_compto compare the first components of the pairs. ...
map<int, ST> mapObj; map<int, ST*> mapPoint; int main() { cout<<"---[create obj]---"<<endl; ST st; cout<<"---[=]---"<<endl; mapObj[0] = st; cout<<"---[repeat-=]---"<<endl; mapObj[0] = st; cout<<"---[insert-pair]---"<<endl; mapObj.insert(pair<int...
std::map<Key,T,Compare,Allocator>::value_comp std::swap(std::map) std::erase_if (std::map) operator==,!=,<,<=,>,>=,<=>(std::map) std::map 的推导指引 std::map<Key,T,Compare,Allocator>::value_compare std::unordered_map std::priority_queue std::span std::forward_list std...
class Compare = less<Key>, // map::key_compare class Alloc = allocator<pair<const Key,T> > // map::allocator_type > class map; struct Cell{ int x; int y; Cell(int _x,int _y):x(_x),y(_y){} }; struct cmp{ bool operator()(const Cell* const c1, const Cell * const c2...
map(InputIt first, InputIt last, constCompare&comp=Compare(), constAllocator&alloc=Allocator()); template<classInputIt> map(InputIt first, InputIt last, constAllocator&alloc); (C++14 起) map(constmap&other); map(constmap&other,constAllocator&alloc); ...
2、如果想把key值按从大到小的顺序排序,改为: map<string, int, std::greater<string>> mapWord2 ; 3、使用比较函数也可以 bool compFunc(const string& a, const string& b) { return a.compare(b) > 0; } map <string, int, decltype(compFunc)*> mapWord3; //注意*号的存在。比较操作类型必...