题解 | #打印日期#

#include <climits>
#include <iostream>
using namespace std;

class  Date {
  public:
    friend ostream& operator<<(ostream& out, const Date& d);
    Date(int year, int month, int day);
    int GetMonthDay(int year, int month);
    Date& operator+=(int day);
  private:
    int _year;
    int _month;
    int _day;
};
Date::Date(int year, int month, int day) {
    _year = year;
    _month = month;
    _day = day;
}
Date& Date::operator+=(int day) {
    _day += day;
    while (_day > GetMonthDay(_year, _month)) {
        _day -= GetMonthDay(_year, _month);
        ++_month;
        if (_month == 13) {
            _year++;
            _month = 1;
        }
    }
    return *this;
}
int Date::GetMonthDay(int year, int month) {
    static int days[13] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    int day = days[month];
    if (month == 2 && ((year % 4 == 0 && year % 100 != 0)
                       || (year % 400 == 0))) {
        day += 1;
    }
    return day;
}
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 << "-" << d._month << "-" << 0 << d._day;
    else if (d._month < 10 && d._day >= 10)
        out << d._year << "-" << 0 << d._month << "-" << d._day;
    else
        out << d._year << "-" << d._month << "-" << d._day;
    return out;
}

void TestDate1() {
    int year = 0, month = 1, day = 0;
    int n = 0;
    while(cin>>year>>n)
    {
        Date d(year,month,day);
        d+=n;
        cout<<d<<endl;
    }
   
}
int main() {
    TestDate1();
    return 0;
}