Mostrando Resultado

void main() {
  print("Welcome to the Simple Calculator!");
  
  // Declarar e inicializar variables numéricas
  double firstNumber = 10.5;
  double secondNumber = 5.5;
  
  // Imprimir los números
  print("First number: $firstNumber");
  print("Second number: $secondNumber");
  
  // Declarar y validar la variable de operación
  String operation = "*";  // Puede ser +, -, *, o /
  
  // Verificar si la operación es válida
  if (operation != '+' && operation != '-' && operation != '*' && operation != '/') {
    print("Invalid operation. Using addition (+) as default.");
    operation = '+';
  }
  
  print("Operation: $operation");
  
  // Realizar el cálculo
  double? result;
  
  if (operation == '+') {
    result = firstNumber + secondNumber;
  } else if (operation == '-') {
    result = firstNumber - secondNumber;
  } else if (operation == '*') {
    result = firstNumber * secondNumber;
  } else if (operation == '/') {
    if (secondNumber == 0) {
      print("Error: Cannot divide by zero!");
      return;
    }
    result = firstNumber / secondNumber;
  }
  
  print("Result: $result");
  
  // Formatear y mostrar el resultado final aquí
}