#include<stdio.h>
mian()
{
    int year,month,day,sum;
    printf("Please enter a date:");
    scanf("%d,%d,%d",&year,&month,&day);
    if((year%4==0&&year%100!=0)||year%400==0)
    {
        printf("This year is a leap yaer.\n");
        switch(month)
        {
        case 1:sum=day;
            break;
        case 2:sum=day+31;
            break;
        case 3:sum=day+31+29;
            break;
        case 4:sum=day+31+29+30;
            break;
        case 5:sum=day+31+29+30+31;
            break;
        case 6:sum=day+31+29+30+31+30;
            break;
        case 7:sum=day+31+29+30+31+30+31;
            break;
        case 8:sum=day+31+29+30+31+30+31+31;
            break;
        case 9:sum=day+31+29+30+31+30+31+31+30;
            break;
        case 10:sum=day+31+29+30+31+30+31+31+30+31;
            break;
        case 11:sum=day+31+29+30+31+30+31+31+30+31+30;
            break;
        case 12:sum=day+31+29+30+31+30+31+31+30+31+30+31;
            break;
        default:sum=-1;
        }
        if(sum=-1)
            printf("Data error!\n");
        else
        printf("Today is %d days of this year!\n",sum);
    }
    else
    {
        printf("This year is a nonleap year.\n");
        switch(month)
        {
        case 1:sum=day;
            break;
        case 2:sum=day+31;
            break;
        case 3:sum=day+31+28;
            break;
        case 4:sum=day+31+28+30;
            break;
        case 5:sum=day+31+28+30+31;
            break;
        case 6:sum=day+31+28+30+31+30;
            break;
        case 7:sum=day+31+28+30+31+30+31;
            break;
        case 8:sum=day+31+28+30+31+30+31+31;
            break;
        case 9:sum=day+31+28+30+31+30+31+31+30;
            break;
        case 10:sum=day+31+28+30+31+30+31+31+30+31;
            break;
        case 11:sum=day+31+28+30+31+30+31+31+30+31+30;
            break;
        case 12:sum=day+31+28+30+31+30+31+31+30+31+30+31;
            break;
        default:sum=-1;
        }
        printf("Today is %d days of this year!\n",sum);
    }
}