Pointers practice improvement - c++

Question

Hello! I wanted to learn more about pointers, so i wrote the following:
struct Data {
int day, month, year;
double hour;
};
class Movie {
protected:
string name;
Data data;
int requiredAge;
int freeSeats;
public:
Movie(){ }
Movie(string moviename, Data dat, int age, int seats) {
name = moviename;
data = dat;
requiredAge = age;
freeSeats = seats;
}
int getFreeSeats() { return freeSeats; }
~Movie(){ }
};
And then i initialize it into the main:
int _tmain(int argc, _TCHAR* argv[])
{
Data d; d.day = 12; d.hour = 16; d.month = 04; d.year = 2016;
Movie movie("Movie Name", d, 16, 35 );
system("pause");
return 1;
}
Why should i use pointers here and where?

Answer 1

The only place where it could make sense to use pointers here is for passing the struct to the constructor:
Movie(string moviename, Data* dat, int age, int seats) {
name = moviename;
data = *dat;
requiredAge = age;
freeSeats = seats;
}
This would avoid creating a complete copy of the struct when the constructor is called. Just passing the pointer is a bit cheaper.
While in C, this would be the only option, in C++ there is a better way: Use references:
Movie( const string& moviename, const Data& dat, int age, int seats) {
name = moviename;
data = dat;
requiredAge = age;
freeSeats = seats;
}
By the way, for the intarguments it is not useful to pass them by reference bacause they are not larger (in terms of bytes) than a pointer.
An even better version would use an initialization list:
Movie( const string& moviename, const Data& dat, int age, int seats)
: name(moviename), data(dat), requiredAge(age), freeSeats(seats) {}
(Thanks for the hint, #NathanOliver)