请问哪里错了?
#include <stdio.h>
int main()
{
int year = 2008;
int month = 8;
int day = 8;
int sum=0;
switch(month-1)
case 7:
sum=sum+31;
case :
sum=sum+30;
case 6:
sum=sum+30;
case 5:
sum=sum+31;
case 4:
sum=sum+30;
case 3:
sum=sum+3;
if(year%4==0)
{
sum=sum+29;
}
else
{
sum=sum+28;
}
case 1:
sum=sum+31;
sum+=8;
printf("%d年%d月%d日是该年的第%d天",year,month,day,sum);