Execute DART Online

import 'dart:io';

void main(){
   var now = new DateTime.now();
   var inp1 = stdin.readLineSync();
   var inp2 = stdin.readLineSync();
   var inp3 = stdin.readLineSync();
   var userday = int.parse(inp1);
   assert(userday is int);
   var usermonth = int.parse(inp2);
   assert(usermonth is int);
   var useryear = int.parse(inp3);
   assert(useryear is int);
   var userbirthday = new DateTime.utc(useryear, usermonth, userday);
   var difference = now.difference(userbirthday);
   print("Your birthdate:");
   print(userbirthday);
   print("Seconds lived:");
   print(difference.inSeconds);
   print("Minutes lived:");
   print(difference.inMinutes);
   print("Hours lived:");
   print(difference.inHours);
   print("Days lived:");
   print(difference.inDays);
   print("Months lived:");
   print(difference.inDays~/30);
   print("Years lived");
   print(difference.inDays~/365);
}