题解 | #日期累加# - 工程代码

#include <iostream>
using namespace std;
int m;
class Date {
public:
    friend istream& operator>>(istream& in, Date& d);
    int GetMonthDay(int year, int month) {
        static int monthDayArr[13] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
        int day = monthDayArr[month];
        if (month == 2 && ((year % 400 == 0) || (year % 4 == 0 && year % 100 != 0))) {
            day += 1;
        }
        return day;
    }
    Date& operator+=(int& add) {
        _day += add;
        while (_day > GetMonthDay(_year, _month)) {
            _day -= GetMonthDay(_year, _month);
            _month++;
            if (_month == 13) {
                _year++;
                _month = 1;
            }
        }
        return *this;
    }
    void Print() {
        printf("%d-%02d-%02d\n", _year, _month, _day);
    }
private:
    int _year = 0;
    int _month = 0;
    int _day = 0;
public:
    int _add = 0;
};
istream& operator>>(istream& in, Date& d) {
    in >> d._year >> d._month >> d._day >> d._add;
    return in;
}
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    cin >> m;
    for (int i = 0; i < m; i++) {
        Date d;
        cin >> d;
        d += d._add;
        d.Print();
    }
    return 0;
}