Date.h

#pragma once
#include <iostream>  
using namespace std;

class Date
{
private:
	int year, month, day;
public:
	//Date() {}
	Date(int year=2018, int month=2, int day=22);
	Date(const Date &d) :year(d.year), month(d.month), day(d.day) {}
	~Date() {}

	//得到年月日  
	int getYear()const { return year; }
	int getMonth()const { return month; }
	int getDay()const { return day; }

	void setDate(int year, int month, int day);   //设置日期  
	bool isLeapYear(int year)const;   //判断是否为闰年  
	int daysOfMonth(int year, int month)const;   //得到某个月的天数  
	void show()const;   //显示日期  
	Date changeDays(const int days)const;   //改变日期  
	int distance(const Date &d)const;   //计算两个日期之间的天数  

										/*重载运算符*/

										//日期加上days个天数  
	friend Date operator +(const Date &d, const int days);
	friend Date operator +(const int days, const Date &d);
	Date& operator +=(int days);
	//日期自增一天  
	Date& operator ++();
	Date operator ++(int);

	//日期减去days个天数  
	friend Date operator -(const Date &d, const int days);
	friend int operator -(const Date &d1, const Date &d2);
	Date& operator -=(int days);
	//日期自减一天  
	Date& operator --();
	Date operator --(int);

	//日期大小比较  
	friend bool operator >(const Date &d1, const Date &d2);
	friend bool operator >=(const Date &d1, const Date &d2);
	friend bool operator <(const Date &d1, const Date &d2);
	friend bool operator <=(const Date &d1, const Date &d2);
	friend bool operator ==(const Date &d1, const Date &d2);
	friend bool operator !=(const Date &d1, const Date &d2);

	//输出，输入日期  
	friend ostream& operator <<(ostream &out, const Date &d);
	friend istream& operator >> (istream &in, Date &d);
};