Error trying to create map outside of main function. C++ - c++

Question

I'm very new to C++ but I am trying to create a map and insert values into it from a class but seem to keep getting an error.
class Album {
public:
map<string,string> albums;
albums.insert(make_pair("rap","Kamikaze")); // This gives the error
};
when i put those same two lines inside the main function, it works without an issue. Like I said I'm very new to C++ so please don't roast me if it's something simple.
(Also, I have map included and using namespace std added)

Answer 1

You are trying to run code in a space where code isn't supposed to be. You can instead write
class Album {
public:
map<string,string> albums;
Album() {
albums.insert(make_pair("rap","Kamikaze"));
}
};
This will run the code every time the class is instantiated, effectively making it the default value for albums.

Answer 2

Class is not a function. Class body can only contain declarations. Executable code may only be in functions (including class methods). For example:
class Album {
public:
map<string,string> albums;
void add_album(string a, string b) {
albums.insert(make_pair(a, b));
// or: albums.emplace(a, b); // if supported
}
};
...
int main() {
...
Album my_album;
my_album.add_album("rap", "Kamikaze");
my_album.albums.insert(make_pair("some", "Thing"));
...
}

Answer 3

No problem its very simple. Below here is a class definition and map that you have declared is its public data member.
Now this Class will act as a prototype for all "Album" objects and all object created will have their own map member.
class Album {
public:
map<string,string> albums;
};
Consider below example,
Album objA; //Object of Album class is created here
//Map being a public member can directly be accessed here
ObjA.albums.insert(make_pair("some", "Thing"));
So instead of calling insert function in class definition you need to do it this way.
Similarly for objectB,
ObjB.albums.insert(make_pair("some", "Thing"));