题解 | #打印日期#

#include <iostream>
using namespace std;
#include <assert.h>

class Date
{
public:
	Date(int year = 1, int month = 1, int day = 1)
	{
			_year = year;
			_month = month;
			_day = day;
	}

	int GetMonthDay(int year, int month)//获得某年某月的具体天数
	{
		static int daysArr[13] = { 0,31,28,31,30,31,30,31,31,30,31,30,31 };//因为查询月份对应的天数这个函数经常调用，每次调用都创建数组太麻烦，直接把这个数组放到静态区，就不用每次调函数都创建数组了
		//用下标映射月份  0月,1, 2 ........

 //if (((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) && month == 2)//这样写每次都要判断闰年，条件有点多，先判断月份效率高a
		if ((month == 2) && (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)))//判断是否为2月，是2月则继续判断是否为闰年,闰年2月是29天
		{
			return 29;
		}

		return daysArr[month];
	}


	Date& getDate(Date d)
	{
		int i = 1;
		while (d._day > 0 && i<13)
		{
			if (d._day <= GetMonthDay(_year, i))
			{
				break;
			}
			else
			{
				d._day -= GetMonthDay(_year, i);
				i++;
			}
			
		}
		_month = i;
		_day = d._day;
		if (_month >= 10 && _day >= 10)
		{
			cout << _year << "-" << _month << "-" << _day << endl;
		}
		else if (_month >= 10 && _day < 10)
		{
			cout << _year << "-" << _month << "-0" << _day << endl;
		}
		else if(_month < 10 && _day >= 10)
		{
			cout << _year << "-0" << _month << "-" << _day << endl;
		}
		else
		{
			cout << _year << "-0" << _month << "-0" << _day << endl;
		}
		return *this;
	}
	void getVal()
	{            
        int year = 0;
        int val = 0;
        while(scanf("%d%d",&year,&val)!=EOF)
        {
            _year = year;
            _month = 1;
            _day = val;
            this->getDate(*this);
        }
	}

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


int main() {
        Date d;
        d.getVal();
}