请分别输入年月日三个数值，计算出这是这一年的第几天？

方法一：

#include <stdio.h>
main()
{int year,month,day,sum;
printf("请输入年，月，日:\n");
scanf("%d,%d,%d",&year,&month,&day);
switch(month)
{case 1:sum=0;break;
  case 2:sum=31;break;
  case 3:sum=59;break;
  case 4:sum=90;break;
  case 5:sum=120;break;
  case 6:sum=151;break;
  case 7:sum=181;break;
  case 8:sum=212;break;
  case 9:sum=243;break;
  case 10:sum=273;break;
  case 11:sum=304;break;
  case 12:sum=334;break;
}
  if((year%100!=0)&(year%4==0)||(year%400==0))
    if(month>2)
    {sum=sum+1;
     sum=sum+day;
    }
    else sum=sum+day;
  else sum=sum+day;

printf("今天是%d年的第%d天\n",year,sum);
}

方法二：

#include<stdio.h>
void main()
{    
int month,year,day,sum,i=0;
while(1)
{   
 printf("请输入年月日:");    
 scanf("%d %d %d",&year,&month,&day);
 if((month>=1&&month<=12)&&(day>=1&&day<=1))
 break;
 else
 printf("数值输入错误，请重新输入\n");
}
switch(month)
{
case 12: i=i+30;
case 11: i=i+31;
case 10: i=i+30;
case 9: i=i+31;
case 8: i=i+31;
case 7: i=i+30;
case 6: i=i+31;
case 5: i=i+30;
case 4: i=i+31;
case 3: i=i+28;
case 2: i=i+31;
case 1: ;
default: ;
}
sum=i+day;
if(((year%4==0&&year%100!=0)||(year%400==0))&&(month>2)) 
sum=sum+1;
printf("今天是%d年的第%d天\n",year,sum);
 }