C++ Using std::unordered_map Declaration and Usage


As already mentioned you can declare an unordered map of any type. Let's have a unordered map named first with string and integer type.

unordered_map<string, int> first; //declaration of the map 
first["One"] = 1; // [] operator used to insert the value 
first["Two"] = 2;
first["Three"] = 3;
first["Four"] = 4;
first["Five"] = 5;

pair <string,int> bar = make_pair("Nine", 9); //make a pair of same type
first.insert(bar); //can also use insert to feed the values