//计算具体天数
int days(int year,int month,int day)
{
    int rn;
    int a[12]={31,28,31,30,31,30,31,31,30,31,30,31};
    int i;
    int sum=0;

    if(year%4==0 && year%100!=0 || year%400==0)
        rn=1;
    else
        rn=0;

    for(i=1;i<month;i++)
        if(i!=2)
            sum+=a[i-1];
        else if(rn==1)
            sum+=29;
        else
            sum+=28;

    sum+=day;
    return sum;
}
void main()
{
    printf("%d\n",days(2016,6,19));
}

又是一个没问题程序