【C++笔记】unordered

利用程序演示相关内容，构建unordered_map mymap。

mymap中的键值对为：国家-首都

// unordered_map::erase
#include 
#include 
#include 

int main ()
{
  std::unordered_map mymap;

  // populating container:
  mymap["U.S."] = "Washington";
  mymap["U.K."] = "London";
  mymap["France"] = "Paris";
  mymap["Russia"] = "Moscow";
  mymap["China"] = "Beijing";
  mymap["Germany"] = "Berlin";
  mymap["Japan"] = "Tokyo";

  // erase examples:
  mymap.erase ( mymap.begin() );      // 根据迭代器进行移除
  mymap.erase ("France");             // 根据键进行移除
  mymap.erase ( mymap.find("China"), mymap.end() ); // 移除某一范围

  // show content:
  for ( auto& x: mymap )
    std::cout << x.first << ": " << x.second << std::endl;

  return 0;
}

得到的结果为：

Russia: Moscow
Japan: Tokyo
U.K.: London