// Enter your date of birth in 3 parts - date (dd), month (mm), year (yyyy) #include #include using namespace std; int now_date, now_month, now_year; bool isLeapYear(int year) { if (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)) return true; return false; } int daysInMonth(int month, int year) { if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12) return 31; else if (month == 4 || month == 6 || month == 9 || month == 11) return 30; else return (isLeapYear(year)) ? (29) : (28); } bool isDOBvalid(int date, int month, int year) { if (year > now_year) { return false; } else if (year == now_year) { if (month > now_month) { return false; } else if (month == now_month) { if (date > now_date) return false; else return true; } else { return true; } } else { return true; } } bool isDATEvalid(int date, int month, int year) { if (year < 1 || month < 1 || month > 12 || date < 1 || date > daysInMonth(month, year)) return false; return true; } long int dates2days(int d1, int m1, int y1, int d2, int m2, int y2) { int days = 0, month, year; // Days in starting year days += daysInMonth(m1, y1) - d1 + 1; month = m1 + 1; while (month <= 12) { days += daysInMonth(month, y1); month++; } // Days after starting year till the end of ending year year = y1 + 1; while (year <= y2) { days += (isLeapYear(year)) ? (366) : (365); year++; } // Days remaining (counted additionally) in ending year REMOVAL days -= daysInMonth(m2, y2) - d2 + 1; month = m2 + 1; while (month <= 12) { days -= daysInMonth(month, y2); month++; } return days; } string date2day(int date, int month, int year) { long int day = dates2days(1, 1, 1, date, month, year) % 7; if (day == 0) return "Monday"; else if (day == 1) return "Tuesday"; else if (day == 2) return "Wednesday"; else if (day == 3) return "Thursday"; else if (day == 4) return "Friday"; else if (day == 5) return "Saturday"; else return "Sunday"; } int main() { // Your DOB (Date Of Birth) int dob_date, dob_month, dob_year; cin >> dob_date; cin >> dob_month; cin >> dob_year; // Today's Date time_t now = time(0); tm *ltm = localtime(&now); now_date = ltm -> tm_mday; now_month = 1 + ltm -> tm_mon; now_year = 1900 + ltm -> tm_year; // Input Date Validation if (cin.fail() || !isDATEvalid(dob_date, dob_month, dob_year)) { cout << "Enter DOB in \"dd mm yyyy\" format!\n\n\"dd\" varies from 01 to 31\n\"mm\" varies from 01 to 12\n\"yyyy\" varies from 0001 to " << static_cast(236) << "\n\nSample Input : 09 12 1996"; return 1; } // Just Born Validation if (dob_date == now_date && dob_month == now_month && dob_year == now_year) { cout << dob_date << "/" << dob_month << "/" << dob_year << " is your DOB!? Are you born today!?"; return 1; } // DOB Validation if (!isDOBvalid(dob_date, dob_month, dob_year)) { cout << dob_date << "/" << dob_month << "/" << dob_year << " is your DOB!? Are you from the future!?"; return 1; } // Happy Birthday if (dob_date == now_date && dob_month == now_month) cout << "Happy Birthday!" << endl; // Your age in days long int age = dates2days(dob_date, dob_month, dob_year, now_date, now_month, now_year); cout << "Your age is " << age << ((age == 1) ? " day." : " days.") << endl; // Your day of birth cout << "You born on " << date2day(dob_date, dob_month, dob_year) << " : " << dob_date << "/" << dob_month << "/" << dob_year << "." << endl; // Your next birthday int next_bday_date = dob_date, next_bday_month = dob_month, next_bday_year = now_year + 1; if (dob_year < now_year && (dob_month > now_month || (dob_month == now_month && dob_date > now_date))) next_bday_year = now_year; if (dob_date == 29 && dob_month == 2) while (!isLeapYear(next_bday_year)) next_bday_year++; cout << "Your next birthday is on " << date2day(next_bday_date, next_bday_month, next_bday_year) << " : " << next_bday_date << "/" << next_bday_month << "/" << next_bday_year << "."; return 0; }

Know your age in days by using c++