C语言-输出第二天日期

#include
#include

struct date
{
    int month;
    int day;
    int year;
};
bool isLeap(struct date d);
int numberOfDays(struct date d);

int main(int argc, char const *argv[]) {

    struct date today, tomorrow;
    
    printf("Enter today's date (mm dd yyyy):");
    scanf("%i %i %i", &today.month, &today.day, &today.year);

    if (today.day != numberOfDays(today)) {
        tomorrow.day = today.day+1;
        tomorrow.month = today.month;
        tomorrow.year = today.year;
    } else if (today.month == 12) {
        tomorrow.day = 1;
        tomorrow.month = 1;
        tomorrow.year = today.year+1;
    } else {
        tomorrow.day = 1;
        tomorrow.month = today.month+1;
        tomorrow.year = today.year;
    }

    printf("Tomorrow's date is %i-%i-%i.\n", 
        tomorrow.month, tomorrow.day, tomorrow.year);
    return 0;
    
}

int numberOfDays(struct date d) {
    int days;
    // 每个月天数
    const int daysPerMonth[12] = {31, 28, 31, 30, 31, 30, 31,31,30,31,30,31};
    // 闰年2月有29天
    if (d.month == 2 && isLeap(d)) {
        days = 29;
    } else {
        days = daysPerMonth[d.month-1];
    }
    return days;
}

bool isLeap(struct  date d)
{
    bool leap = false;
    // 闰年是指公历年份中能够被4整除但不能被100整除，或者能够被400整除的年份
    if ((d.year%4==0 && d.year%100!=0)) {
        leap = true;
    } 
    return leap;
}