给出日期求是第几天，小白。求关注
111#include<stdio.h>
void main()
{
int year,days,month,t;
printf("plz input data:");
scanf("%d%d%d",&year,&month,&days);
if(year%4==0&&year%100!=0||year%400==0&&month>=2) t=29;
else t=28;
switch(month)
case 12 :days+=31;
case 11 :days+=30;
case 10 :days+=31;
case 9 :days+=30;
case 8 :days+=31;
case 7 :days+=31;
case 6 :days+=30;
case 5 :days+=31;
case 4 :days+=30;
case 3 :days+=t;
case 2 :days+=31;
case 1 :days+=0;
printf("%d"\n,days);//我没加break 想着逻辑是不是通的？
}怎么执行提示说非法？
[解决办法]
printf("%d"\n,days);改成printf("%d\n",days);
另外，从case 4往上都加错了。
