#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<cmath>
using namespace std;
inline void keep_window_open() { char ch; cin >> ch; }

class Date {
    int y, m, d;

public:
    Date(int d, int m, int y);
};

class Book {
    string title;
    string author;
    string isbn;
    Date date;

public:
    Book(string t, string a, string id, Date d);
};

int main() {
    Book Charlie("charlie", "gates", "333H", Date(1, 2, 3));
}