#define NOTE_C4  262
#define NOTE_D4  294
#define NOTE_E4  330
#define NOTE_F4  349
#define NOTE_G4  392
#define NOTE_A4  440
#define NOTE_B4  494
#define NOTE_C5  523

const int buttonPins[] = {16, 17, 5, 18, 19, 21, 22, 23};
const int speakerPin = 13;

int notes[] = {NOTE_C4, NOTE_D4, NOTE_E4, NOTE_F4, NOTE_G4, NOTE_A4, NOTE_B4, NOTE_C5};

void setup() {
  pinMode(speakerPin, OUTPUT); 
  for (int i = 0; i < 8; i++) {
    pinMode(buttonPins[i], INPUT_PULLUP); 
  }
}

void loop() {
  for (int i = 0; i < 8; i++) {
    if (digitalRead(buttonPins[i]) == LOW) {
      tone(speakerPin, notes[i]); 
      delay(300); 
      noTone(speakerPin); 
    }
  }
}