Program/Cpp/Map

std::unordered_map<std::string, std::int> umap; //定义

umap.insert(Map::value_type("test", 1));//增加

//根据key删除,如果没找到n=0
auto n = umap.erase("test")   //删除

auto it = umap.find(key) //改
if(it != umap.end()) 
    it->second = new_value; 


//map中查找x是否存在
umap.find(x) != map.end()//查
//或者
umap.count(x) != 0