题解 | #打印日期#

# define _CRT_SECURE_NO_WARNINGS 1
#include <iostream>
#include <stdbool.h>
using namespace std;



class Date
{
    friend ostream& operator<<(ostream& out, const Date& d);
public:
    Date(int year = 1, int month = 1, int day = 0)
        :_year(year)
        , _month(month)
        , _day(day)
    {}
    int GetMonthDay(int year, int month);
    bool operator<(Date& d)
    {
        if (_year < d._year)
        {
            return true;
        }
        else if (_year == d._year)
        {
            if (_month < d._month)
            {
                return true;
            }
            else if (_month == d._month)
            {
                if (_day < d._day)
                {
                    return true;
                }
            }
        }

        return false;
    }

    bool operator==(Date& d)
    {
        return _year == d._year
            && _month == d._month
            && _day == d._day;
    }

    Date operator+(int day)
    {
        Date temp = *this;
        temp += day;

        return temp;

    }
    Date& operator++()
    {
        *this += 1;
        return *this;
    }

    //d1+=50
    Date& operator+=(int day)
    {
        _day += day;

        while (_day > GetMonthDay(_year, _month))
        {
            //cout << _year <<' '<< _month << endl;
            //cout << GetMonthDay(_year, _month) << endl;

            _day -= GetMonthDay(_year, _month);
            ++_month;
            
            if (13 == _month)
            {
                _month = 1;
                ++_year;
            }
        }
        
        return *this;
    }

private:
    int _year ;
    int _month;
    int _day ;
};

int Date::GetMonthDay(int year, int month)
{
    static int Monthday[13] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };
    if (month == 2 && ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)))
    {
        return 29;
    }
    else
    {
        return Monthday[month];
    }
}

ostream& operator<<(ostream& out, const Date& d)
{
    if (d._month < 10 && d._day < 10)
    {
        out << d._year << "-0" << d._month << "-0" << d._day;
    }
    else if(d._month < 10 && d._day >= 10)
    {
        out << d._year << "-0" << d._month << "-" << d._day;
    }
    else if (d._month >= 10 && d._day < 10)
    {
        out << d._year << "-" << d._month << "-0" << d._day;
    }
    else
    {
        out << d._year << "-" << d._month << "-" << d._day;
    }
    return out;
}



int main()
{
    int year = 2000, month = 1, day = 0;
    int n = 0;
    while (cin >> year >> n)
    {
        Date d1(year, month, day);
        Date d2 = d1 + n;
        cout << d2 << endl;

    }
    return 0;
}