HDU2005 第几天

#include <iostream>
#include <cstdio>
#include <cmath>

bool IsLeapYear(int year)
{
	return ((year%4==0&&year%100!=0) || year%400==0);
}

using namespace std;
int main()
{
	int year, month, day;
	while(scanf("%d/%d/%d", &year, &month, &day) != EOF)
	{
		int sum = 0;
		switch(month-1)
		{
		case 11:
			sum += 30;
		case 10:
			sum += 31;
		case 9:
			sum += 30;
		case 8:
			sum += 31;
		case 7:
			sum += 31;
		case 6:
			sum += 30;
		case 5:
			sum += 31;
		case 4:
			sum += 30;
		case 3:
			sum += 31;
		case 2:
			if(IsLeapYear(year))
				sum += 29;
			else
				sum += 28;
		case 1:
			sum += 31;
		}
		sum += day;
		cout << sum << endl;
	}
	return 0;
}