题解 | #计算日期到天数转换#

#include <iostream>
using namespace std;

class Date {
private:
    friend std::istream& operator>>(std::istream& _cin, Date& d);

    // 判断是否为闰年
    bool isLeapYear(int year) const {
        return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
    }

    // 获取任意月份的天数
    int GetMonthDay(int year, int month) {
        static int monthArray[13] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
        int day = monthArray[month];

        // 判断是否是闰年闰月
        if (month == 2 && isLeapYear(year)) {
            day = 29;
        }

        return day;
    }

public:
    // 构造函数
    Date(int year, int month = 1, int day = 1) {
        _year = year;
        _month = month;
        _day = day;
    }

    bool operator!=(const Date& d) const {
        if (this->_year == d._year && this->_month == d._month && this->_day == d._day) {
            return false;
        }
        return true;
    }

    Date& operator+=(int day) { // Date& operator+=(Date* this, int day)
        _day += day;
        while (_day > GetMonthDay(_year, _month)) {
            // 如果日期不合法，就要往月进位
            _day -= GetMonthDay(_year, _month);
            _month++;

            // 如果月不合法，就要往年进位
            if (_month > 12) {
                _year++;
                _month = 1;
            }
        }

        return *this;
    }

    int operator-(const Date& d) {
        Date max = *this;
        Date min = d;
        int flag = 1;

        int count = 0;
        while (min != max) {
            min += 1;
            count++;
        }

        return count * flag;
    }

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

istream& operator>>(istream& _cin, Date& d) {
    _cin >> d._year >> d._month >> d._day;
    return _cin;
}

int main() {
    int year, month, day;

    while (cin >> year >> month >> day) {
        Date d1(year, month, day);
        Date d2(year, 1, 0);
        cout << d1 - d2;
    }

    return 0;
}

如果你想看一个更完备的Date类，速通所有关于日期类的程序题，可以关注一下我新写的博客。学会Date类的编写，可以根据题目要求，自定义裁切Date类完成解答。 https://blog.csdn.net/mmlhbjk/article/details/141825524?spm=1001.2014.3001.5502