c++ how do you implement a has relationship? - c++

Question

for example:
i got great reservations:
the class has memeber the start/end date and a function that gives me the date.
class reservation{
private:
datetime start;
datetime end;
public:
reservation(stardatetime, enddatetime): start(stardatetime), end(enddatetime)
{
}
std::list<std::string> get_reservation()
{
for example: return start;
}
};
and i have a class conference room, which can be booked from one time to another.
class room{
private:
int room_ID;
public:
room(int id):room_ID(id)
{
}
void get_room(){
return room_id;
}
}
that means every room has several reservations.
how can i access through a room id via the reservation?
if i search for room id 1, the reservation of the room will also be displayed.
Thanks.

Answer 1

Here's your problem statement: every room has many reservations, and every reservation has a reference to a single room. Based on this, I would write it as follows (you may add your stuff inside those classes).
#include <iostream>
#include <vector>
using namespace std;
class Room; //forward declaration
class Reservation {
private:
Room* room;
public:
Reservation(Room* roomPtr) {
room = roomPtr;
}
};
class Room {
vector<Reservation> reservations;
};
int main(){
Room room[10]; //an array of 10 rooms with no reservations (calls def.constructor of each Room)
Reservation r1(&room[0]); //reservation object r1 reserving room[0]
Reservation r2(&room[1]); //reservation object r2 reserving room[1]
// ...more stuff goes here
}