#include <map>

//tuple多元数组，必须是静态数组，类似结构体

//配合array，vector使用

//std::tuple<数组元素类型>数组变量名(数组元素变量名);

 #include <iostream>
 #include <map>
 using namespace std;

 //tuple多元数组，必须是静态数组，类似结构体
 //配合array，vector使用

 void main()
 {
     int int1();
     double double1(99.8);
     char ch1('A');
     char *str = "hello";

     //std::tuple<数组元素类型>数组变量名(数组元素变量名);
     std::tuple<int, double, char, const char *>mytuple(int1, double1, ch1, str);//创建一个多元数组，可以存放不同类型的元素

     auto data0 = std::get<>(mytuple);//下标只能是常量
     auto data1 = std::get<>(mytuple);
     auto data2 = std::get<>(mytuple);
     auto data3 = std::get<>(mytuple);

     std::cout << typeid(data0).name() << " " << data0 << std::endl;//在C++中，typeid用于返回指针或引用所指对象的实际类型。
     std::cout << typeid(data1).name() << " " << data1 << std::endl;
     std::cout << typeid(data2).name() << " " << data2 << std::endl;
     std::cout << typeid(data3).name() << " " << data3 << std::endl;

     decltype(data0) dataA;//根据一个变量，创建一个备份

     system("pause");
 }

map, multimap的区别：map每一个结点是映射，multimap每一个结点是映射链表的开头

1 map

2 multimap

1 map

映射(map) 由{键，值}对组成的集合，以某种作用于键对上的谓词排列 <map>

如果已经有重复的元素，将会插入失败

 #include <iostream>
 #include <map>

 int main()
 {
     std::map<const char *, int>mymap;

     mymap.insert(std::pair<const char *, int>("司令1", ));
     mymap.insert(std::pair<const char *, int>("司令2", ));
     mymap.insert(std::pair<const char *, int>("司令3", ));
     mymap.insert(std::pair<const char *, int>("司令4", ));

     mymap.insert(std::pair<const char *, int>("司令1", ));//如果已经有重复的元素，将会插入失败

     auto ib = mymap.begin();
     auto ie = mymap.end();

     for (; ib != ie; ib++)
     {
         std::cout << ib->first << " " << ib->second << std::endl;
     }

     return ;
 }

映射

 #include <iostream>
 #include <map>

 struct student
 {
     char *name;
     int year;
 };

 struct stuinfo
 {
     int id;
     student stu;
 };

 int main()
 {
     stuinfo infoarray[] = { {,{"hello",}},{ ,{ "hello", }},{,{ "hello", }} };

     std::map<int, student>m;

     for (int i = ; i < ; i++)
     {
         m[infoarray[i].id] = infoarray[i].stu;
     }

     auto ib = m.begin();
     auto ie = m.end();

     for (; ib != ie; ib++)//遍历
     {
         std::cout << (*ib).first << " ";
         std::cout << (*ib).second.name << " " << (*ib).second.year << std::endl;
     }

     return ;
 }

2 multimap

 #include <iostream>
 #include <map>

 int main()
 {
     std::multimap<const char *, int>mymap;

     mymap.insert(std::pair<const char *, int>("司令1", ));
     mymap.insert(std::pair<const char *, int>("司令2", ));
     mymap.insert(std::pair<const char *, int>("司令3", ));
     mymap.insert(std::pair<const char *, int>("司令4", ));

     mymap.insert(std::pair<const char *, int>("司令1", ));//multimap如果有重复，也会插入成功

     auto ib = mymap.begin();
     auto ie = mymap.end();

     for (; ib != ie; ib++)
     {
         std::cout << ib->first << " " << ib->second << std::endl;
     }

     return ;
 }

multimap的元素可以重复，因此equal_range(const T&);可以实现查找多个相同的元素

 #include <iostream>
 #include <map>
 #include <string>

 void main()
 {
     std::multimap<std::string, std::string>mymap;

     mymap.insert(std::pair<std::string, std::string>("hello", "a"));
     mymap.insert(std::pair<std::string, std::string>("world", "b"));
     mymap.insert(std::pair<std::string, std::string>("hello", "c"));
     mymap.insert(std::pair<std::string, std::string>("world", "d"));

     auto ib = mymap.begin();
     auto ie = mymap.end();

     for (; ib != ie; ib++)
     {
         std::cout << ib->first << " " << ib->second << std::endl;
     }
     std::cout << std::endl;

     auto pfind = mymap.find("hello");//查找
     std::cout << pfind->first << " " << pfind->second << std::endl << std::endl;//只输出查找的第一个元素

     auto it = mymap.equal_range("hello");
     for (auto i = it.first; i != it.second; i++)
     {
         std::cout << i->first << " " << i->second << std::endl;
     }
 }