第七章第2小題

#include <iostream>
using namespace std;
struct date
{
	int year;
	int month;
	int days;
};
int main()
{
	int days(date);
	date d1;
	cin>>d1.year;
	cin>>d1.month;
	cin>>d1.days;
	cout<<"您輸入的時間是"<<d1.year<<"年"<<d1.month<<"月"<<d1.days<<"日"<<endl;
	cout<<"該日在本年中是第"<<days(d1)<<"天"<<endl;
	return 0;
}
int days(date d)
{
	int run(date);
	if (run(d)==1)
	{
		switch(d.month)
		{
		case 1:return d.days;break;
		case 2:return 31+d.days;break;
		case 3:return 60+d.days;break;
		case 4:return 91+d.days;break;
		case 5:return 121+d.days;break;
		case 6:return 152+d.days;break;
		case 7:return 182+d.days;break;
		case 8:return 213+d.days;break;
		case 9:return 244+d.days;break;
		case 10:return 274+d.days;break;
		case 11:return 305+d.days;break;
		case 12:return 335+d.days;break;
		}
	}
	else
	{
		switch(d.month)
		{
		case 1:return d.days;break;
		case 2:return 31+d.days;break;
		case 3:return 59+d.days;break;
		case 4:return 90+d.days;break;
		case 5:return 120+d.days;break;
		case 6:return 151+d.days;break;
		case 7:return 181+d.days;break;
		case 8:return 212+d.days;break;
		case 9:return 243+d.days;break;
		case 10:return 273+d.days;break;
		case 11:return 304+d.days;break;
		case 12:return 334+d.days;break;
		}
	}
}
int run(date d)
{
	bool leap;
	if(d.year%4==0)
	{
		if(d.year%100==0)
		{
			if(d.year%400==0)
				leap=true;
			else 
				leap=false;
		}
		else
			leap=true;
	}
	else
		leap=false;
	if(leap==true)
		return 1;
	else 
		return 0;
}