import 'dart:io';

// تعريف المتغيرات الأساسية
bool lightsOn = false;
double thermostatTemp = 20.0;
bool securityArmed = false;

void main() {
  while (true) {
    print("\nWelcome to the Smart Home System!");
    print("Please choose an action:");
    print("1. Toggle lights");
    print("2. Set thermostat temperature");
    print("3. Arm/disarm security system");
    print("4. View system status");
    print("5. Exit");

    stdout.write("\nEnter your choice: ");
    String? choice = stdin.readLineSync();

    switch (choice) {
      case '1':
        lightsOn = !lightsOn;
        print("Lights are now ${lightsOn ? 'ON' : 'OFF'}.");
        break;
      case '2':
        stdout.write("Set thermostat temperature (15°C - 30°C): ");
        double? temp = double.tryParse(stdin.readLineSync()!);
        if (temp != null && temp >= 15 && temp <= 30) {
          thermostatTemp = temp;
          print("Thermostat set to ${thermostatTemp}°C.");
        } else {
          print("Invalid temperature! Please enter a value between 15 and 30.");
        }
        break;
      case '3':
        securityArmed = !securityArmed;
        print("Security system is now ${securityArmed ? 'ARMED' : 'DISARMED'}.");
        break;
      case '4':
        print("\nSystem Status:");
        print("Lights: ${lightsOn ? 'ON' : 'OFF'}");
        print("Thermostat: ${thermostatTemp}°C");
        print("Security System: ${securityArmed ? 'ARMED' : 'DISARMED'}");
        break;
      case '5':
        print("Exiting the system. Goodbye!");
        return;
      default:
        print("Invalid choice! Please enter a number from 1 to 5.");
    }
  }
}


السؤال الثاني 


import 'dart:io';

List<Map<String, double>> incomeList = [];
List<Map<String, double>> expenseList = [];

void main() {
  while (true) {
    print("\nWelcome to the Budget Management Application!");
    print("1. Add income");
    print("2. Add expense");
    print("3. View summary");
    print("4. Exit");

    stdout.write("\nEnter your choice: ");
    String? choice = stdin.readLineSync();

    switch (choice) {
      case '1':
        addIncome();
        break;
      case '2':
        addExpense();
        break;
      case '3':
        viewSummary();
        break;
      case '4':
        print("Exiting the application. Goodbye!");
        return;
      default:
        print("Invalid choice! Please enter a number from 1 to 4.");
    }
  }
}

void addIncome() {
  stdout.write("Enter income source: ");
  String source = stdin.readLineSync()!;
  stdout.write("Enter income amount: ");
  double? amount = double.tryParse(stdin.readLineSync()!);
  
  if (amount != null && amount > 0) {
    incomeList.add({source: amount});
    print("Income added successfully.");
  } else {
    print("Invalid amount! Please enter a positive number.");
  }
}

void addExpense() {
  stdout.write("Enter expense category: ");
  String category = stdin.readLineSync()!;
  stdout.write("Enter expense amount: ");
  double? amount = double.tryParse(stdin.readLineSync()!);
  
  if (amount != null && amount > 0) {
    expenseList.add({category: amount});
    print("Expense added successfully.");
  } else {
    print("Invalid amount! Please enter a positive number.");
  }
}

void viewSummary() {
  double totalIncome = incomeList.fold(0, (sum, item) => sum + item.values.first);
  double totalExpenses = expenseList.fold(0, (sum, item) => sum + item.values.first);
  double netProfit = totalIncome - totalExpenses;
  double tax = netProfit > 0 ? netProfit * 0.15 : 0;

  print("\nSummary:");
  print("Total Income: \$${totalIncome.toStringAsFixed(2)}");
  print("Total Expenses: \$${totalExpenses.toStringAsFixed(2)}");
  print("Net Profit: \$${netProfit.toStringAsFixed(2)}");

  if (netProfit > 0) {
    print("Tax to be paid (15%): \$${tax.toStringAsFixed(2)}");
  }
}