#include <iostream>
using std::ostream;

namespace zv
{
    class date
    {
    private:
        int day, month, year;
    public:
        date(int d, int m, int y) : day(d), month(m), year(y) {}
        friend ostream& operator<<(ostream& out, const zv::date &a);
    };
    
    ostream& operator<<(ostream& out, const zv::date &a)
    {
        return out << a.day << '/' << a.month << '/' << a.year;
    }
}

int main()
{
    zv::date a(1,1,2000);
    std::cout << a;
}