#include "class_date.h"
#include <iostream>
using namespace std;
//注意一下年份的调整！！！
Date Date::operator+=(int day)//日期加天数，注意要对原对象进行修改
{
	_day += day;
	while(_day > GetMonthDay(_year, _month))//如果天数大于，进行进位
	{
		if (_month > 12)//月份超过，再对于进行进位
		{
			_month = 1;
			_year++;
		}	
		_day = _day - GetMonthDay(_year, _month);
		_month++;
	}
	return *this;

}
Date Date::operator+(int day)//加法，对原对象不进行处理
{
	Date tmp = *this;
	tmp += day;
	return tmp;
}
Date Date::operator-=(int day)
{
	_day -= day;
	if (_day < 0)//天数为负，向前一位进行借位
	{
		if (_month < 1)//依旧进行调整
		{
			_month = 12;
			_year--;
		}
		--_month;
		_day += GetMonthDay(_year, _month);
		
	}
	return *this;
}
Date Date::operator-(int day)
{
	Date tmp = *this;
	tmp -= day;
	return tmp;
}
void Date::Printf()
{
	cout << _year << "-" << _month << "-" << _day << endl;
}