Since songNUMBER is a String, it will manage its own memory usage properly. As long as you have a reasonable amount of free RAM (i.e. - "dynamic memory" in Arduino-speak), you should be just fine.
Since songNUMBER is a String, it will manage its own memory usage properly. As long as you have a reasonable amount of free RAM (i.e. - "dynamic memory" in Arduino-speak), you should be just fine.