daysInMonth function
returns number of days in given month
Implementation
int daysInMonth(int monthNum, int year) {
List<int> monthLength = List.filled(12, 0);
monthLength[0] = 31;
monthLength[2] = 31;
monthLength[4] = 31;
monthLength[6] = 31;
monthLength[7] = 31;
monthLength[9] = 31;
monthLength[11] = 31;
monthLength[3] = 30;
monthLength[8] = 30;
monthLength[5] = 30;
monthLength[10] = 30;
if (leapYear(year)) {
monthLength[1] = 29;
} else {
monthLength[1] = 28;
}
return monthLength[monthNum - 1];
}