20.日期计算

#include<stdio.h>
int runyear(int year)
{
int mark = 0;
if(year%4 == 0 && year%100 != 0 )
{
mark =1;
}
if(year%400 == 0)
{
mark = 1;
}
return mark;
}
int addmonth(int month,int year)
{
int addnum = 0; 
switch(1)
{
case 1:if(month<=1){break;}addnum += 31;
case 2:if(month<=2){break;}
if(runyear(year))
  {
addnum += 29;
  }
else{
addnum += 28;
}
case 3:if(month<=3){break;}addnum +=31;
case 4:if(month<=4){break;}addnum +=30;
case 5:if(month<=5){break;}addnum +=31;
case 6:if(month<=6){break;}addnum +=30;
case 7:if(month<=7){break;}addnum +=31;
case 8:if(month<=8){break;}addnum +=31;
case 9:if(month<=9){break;}addnum +=30;
case 10:if(month<=10){break;}addnum +=31;
case 11:if(month<=11){break;}addnum +=30;
case 12:if(month<=12){break;}addnum +=31;
default :break;
}
return addnum;
}
int main()
{
int N;
int totalday = 0;
int year,month,day;
scanf("%d",&N);
while(N--)
{
scanf("%d %d %d",&year,&month,&day);
totalday = addmonth(month,year);
totalday += day;
printf("%d\n",totalday);
}
return 0;
}