// Pin for the buzzer
const int buzzerPin = 9;

// Frequencies of the notes (in Hertz)
#define NOTE_C4 261
#define NOTE_D4 294
#define NOTE_E4 329
#define NOTE_F4 349
#define NOTE_G4 392
#define NOTE_A4 440
#define NOTE_B4 494
#define NOTE_C5 523

// Melody of "Twinkle, Twinkle, Little Star"
int melody[] = {
  NOTE_C4, NOTE_C4, NOTE_G4, NOTE_G4,
  NOTE_A4, NOTE_A4, NOTE_G4, NOTE_F4,
  NOTE_F4, NOTE_E4, NOTE_E4, NOTE_D4,
  NOTE_D4, NOTE_C4
};

// Durations of each note (in ms)
int noteDurations[] = {
  400, 400, 400, 400,
  400, 400, 400, 400,
  400, 400, 400, 400,
  400, 400
};

void setup() {
  pinMode(buzzerPin, OUTPUT);
}

void loop() {
  // Play each note in the melody
  for (int thisNote = 0; thisNote < 14; thisNote++) {
    int noteDuration = noteDurations[thisNote];
    tone(buzzerPin, melody[thisNote], noteDuration);
    // Wait for the note to finish playing
    int pauseBetweenNotes = noteDuration * 1.30;
    delay(pauseBetweenNotes);
    noTone(buzzerPin);
  }
  // Wait before repeating the melody
  delay(2000);
}