#include <iostream>
#include <cstdlib>
#include <ctime>  // Required for default constructor (time, localtime)
using namespace std;

class date {
public:
    int year;
    int month;  // 1 to 12 inclusive
    int day;    // 1 to 31 depending on month

    date(int y, int m, int d);      
    date();                         

    void print() const;
    void next();                    
    void next(int n);              
    void prev();                    
    void prev(int n);              
};

date::date(int y, int m, int d) {
    year = y;
    month = m;
    day = d;
}

date::date() {
    time_t now = time(0);
    tm* lt = localtime(&now);
    year = lt->tm_year + 1900;
    month = lt->tm_mon + 1;
    day = lt->tm_mday;
}

void date::next() {
    static const int daysInMonth[] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };

    int leap = (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
    int days = (month == 2 && leap) ? 29 : daysInMonth[month];

    if (++day > days) {
        day = 1;
        if (++month > 12) {
            month = 1;
            ++year;
        }
    }
}

void date::next(int n) {
    for (int i = 0; i < n; ++i)
        next();
}

void date::prev() {
    static const int daysInMonth[] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };

    if (--day < 1) {
        if (--month < 1) {
            month = 12;
            --year;
        }
        int leap = (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
        day = (month == 2 && leap) ? 29 : daysInMonth[month];
    }
}

void date::prev(int n) {
    for (int i = 0; i < n; ++i)
        prev();
}

void date::print() const {
    cout << year << "-" << month << "-" << day << '\n';
}

int main() {
    const date today;    /
    today.print();

    date d(2025, 6, 4);
    d.print();

    d.next();
    d.print();

    d.prev();
    d.print();

    d.next(5);
    d.print();

    d.prev(5);
    d.print();

    return 0;
}