void setup() {
  pinMode(buzzer, OUTPUT); // set buzzer pin as output



void loop() {
  // notes of the song in ascending order
  int notes[] = {69, 72, 74, 76, 77, 79, 81, 79, 77, 76, 74, 72, 70, 69};
  // duration of each note in milliseconds
  int durations[] = {500, 500, 500, 500, 500, 500, 500, 250, 250, 500, 500, 500, 500, 500};

  // play the song
  for (int i = 0; i < sizeof(notes) / sizeof(notes[0]); i++) {
    tone(buzzer, notes[i]);
    delay(durations[i]);
    noTone(buzzer);
  }
}