C语言实现从键盘输入年月日，输出该月的天数

代码如下：

#include 

int main(){
	int year,month,days;
	printf("请输入年月\n");
	scanf("%d%d",&year,&month);
	switch(month){
	  case 1:
	  case 3:
	  case 5:
	  case 7:
	  case 8:
	  case 10:
	  case 12: days=31;break;
	  case 4:
	  case 6:
	  case 9:
	  case 11: days = 30;break;
	  case 2:if((year%4==0)&&(year%100!=0)||year%400==0){
			 days = 29;
			 }else {
				days = 28;
			 }
			 break;
	  default: printf("输入的年月有问题");
	
	}
	printf("year=%d,month=%d,days=%d\n",year,month,days);
	return 0;
}