题解 | #获得月份天数#

#include <stdio.h>

int main() {
	int year, mon;
	while (~scanf("%4d%2d", &year, &mon))
	{
		switch (mon) {
		case 1:
		case 3:
		case 5:
		case 7:
		case 8:
		case 10:
		case 12:printf("31\n"); break;
		case 4:
		case 6:
		case 9:
		case 11:printf("30\n"); break;
		case 2:
			if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0)
				printf("29\n");
			else
				printf("28\n");
		}
	}
	return 0;
}