import 'dart:io';

void main() {
  double ticketPrice = 50.0;
  int ticketsSold = 0;

  // Ticket sales loop
  while (ticketsSold < 200) {
    ticketsSold += 20;
  }

  double revenue = ticketsSold * ticketPrice;
  print("Total tickets sold: $ticketsSold");
  print("Total revenue: \$${revenue}");

  // Age-based discount
  print("Enter customer age:");
  int age = int.parse(stdin.readLineSync()!);

  if (age >= 60) {
    print("Senior discount applied!");
  } else if (age < 12) {
    print("Child discount applied!");
  } else {
    print("No discount available.");
  }

  // Late fee using ternary operator
  int hour = 22;
  double lateFee = hour > 21 ? 10.0 : 0.0;
  print("Late fee: \$${lateFee}");
}