#include <stdio.h>

int main()
{
    int day = 0, month = 0, year = 0, dayLimit = 31;

    printf("Input the date (syntax: dd.mm.yyyy (example: 08.12.2005) (year should be lower or equals to 2017)): ");
    scanf("%d.%d.%d", &day, &month, &year);
    getchar(); //clean buffer

    if ((day < 1 || day > 31) || (month < 1 || month > 12) || (year < 1 || year > 2017)) //check if wrong input (check 1/2)
    {
        printf("[a] wrong input.\n");
        return -1; //stop program
    }
    switch(month) //check if the number of days correct (according the month, for example: in february - 28 days, and not 29) (check 2/2)
    {
        case 2: //check if the month equals to february, and if the days don't greater than 28
            if (day > 28)
            {
                printf("[b] wrong input.\n");
                return -1; //stop program
            }
            dayLimit = 28; //setting the limit of the days in this month to 28
            break;

        case 4: //check if the month equals to: april(4), june(6), september(9), november(11), and if the days don't greater than 30
        case 6:
        case 9:
        case 11:
            if (day > 30)
            {
                printf("[b] wrong input.\n");
                return -1; //stop program
            }
            dayLimit = 30; //setting the limit of the days in this month to 30
            break;
    }

    day++; //adding one day

    if (day > dayLimit) //checks if the day passed the limit (according the months)
    {
        month++; //increase month by 1
        day = 1;

        if (month > 12) //checks if the month passed the max limit (12)
        {
            year++; //increase year by 1
            month = 1;
        }
    }
    printf("The next day will be: %02d.%02d.%04d\n", day, month, year);
    //02d -> if the days lower than 2 numbers it will add 0 to the beginning (days: 2, output: 02)
    //04d -> if the year lower than 4 numbers it will add zeros to the beginning (year: 10, output: 0010)

    getchar();
    return 0;
}