int sum;

    swtich(month)

    {

        case 1:sum=0;break;

        case 2:sum=28;break;

        case 3:sum=(28+31);break;

        case 4:sum=(28+31+30);break;

        case 5:sum=(28+31+30+31);break;

        case 6:sum=(28+31+30+31+30);break;

        case 7:sum=(28+31+30+31+30+31);break;

        case 8:sum=(28+31+30+31+30+31+31);break;

        case 9:sum=(28+31+30+31+30+31+31+30);break;

        case 10:sum=(28+31+30+31+30+31+31+30+31);break;

        case 11:sum=(28+31+30+31+30+31+31+30+31+30);break;

        case 12:sum=(28+31+30+31+30+31+31+30+31+30+31);break;

        default: ;

    }

    if(year%400==0||(year%400!=0&&year%4==0))

    {

        sum=sum+day+1;

        printf("%d年%d月%d日是该年的第%d天",year,month,day,sum);

    }

    else

    {

        sum=sum+day;

        printf("%d年%d月%d日是该年的第%d天",year,month,day,sum);

    }

return 0;

}