@Override
	public void start(Stage primaryStage) {
		try {
			Parent root = FXMLLoader.load(getClass().getResource("calculator.fxml"));
			Scene scene = new Scene(root);
			primaryStage.setScene(scene);
			primaryStage.setTitle("Calculator");
			primaryStage.show();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}