Assignment 2: Budget

 import 'dart:io';
 void main() {
  List<Map<String, double>> incomeList = [];
  List<Map<String, double>> expenseList = [];
  while (true) {
    print('\n--- Budget Manager ---');
    print('1. Add income');
    print('2. Add expense');
    print('3. View summary');
    print('4. Exit');
    stdout.write('Enter your choice: ');
    String? choice = stdin.readLineSync();
    if (choice == '1') {
      stdout.write('Description: ');
      String? desc = stdin.readLineSync()?.trim();
      if (desc == null || desc.isEmpty) {
        print('Description cannot be empty.');
        continue;
      }
      stdout.write('Amount: ');
      double? amount = double.tryParse(stdin.readLineSync() ?? '');
      if (amount == null || amount <= 0) {
        print('Amount must be a positive number.');
        continue;
      }
      incomeList.add({desc: amount});
      print('Added income: $desc - \$${amount.toStringAsFixed(2)}');
    } else if (choice == '2') {
      stdout.write('Description: ');
      String? desc = stdin.readLineSync()?.trim();
      if (desc == null || desc.isEmpty) {
        print('Description cannot be empty.');
        continue;
      }
      stdout.write('Amount: ');
      double? amount = double.tryParse(stdin.readLineSync() ?? '');
      if (amount == null || amount <= 0) {
        print('Amount must be a positive number.');
        continue;
      }
      expenseList.add({desc: amount});
      print('Added expense: $desc - \$${amount.toStringAsFixed(2)}');
    } else if (choice == '3') {
      double totalIncome = 0;
      for (var item in incomeList) {
      }
        totalIncome += item.values.first;
      double totalExpense = 0;
      for (var item in expenseList) {
        totalExpense += item.values.first;
      }
      double net = totalIncome - totalExpense;
      if (net >= 0) {
        print('Your net profit is \$${net.toStringAsFixed(2)}');
        double tax = net > 0 ? net * 0.15 : 0.0;
        if (tax > 0) {
          print('Tax to pay (15%): \$${tax.toStringAsFixed(2)}');
        }
      } else {
        print('Your net loss is \$${(-net).toStringAsFixed(2)}');
      }
      print('\nIncome:');
      if (incomeList.isEmpty)
        print('  None');
      else
        for (var inc in incomeList)
          inc.forEach((d, a) => print('  $d: \$${a.toStringAsFixed(2)}'));
      print('\nExpenses:');
      if (expenseList.isEmpty)
        print('  None');
      else
        for (var exp in expenseList)
          exp.forEach((d, a) => print('  $d: \$${a.toStringAsFixed(2)}'));
    } else if (choice == '4') {
      print('Goodbye!');
      break;
    } else {
      print('Invalid choice. Try again.');
    }
  }
 }