这是很简单的思路
#include <stdio.h>
int main()
{
int i = 2008,sum=0;
int m = 8;
int d = 8;
switch(m-1){
case 12: sum+=31;
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(i%4==0&&i%100!=0||i%400==0)sum+=29;
else sum+=28;
case 1:sum+=31;break;
}
printf("%d年%d月%d日是该年的第%d天,",i,m,d,sum+d);
return 0;
}