#include "pitches.h"
#define SPEAKER_PIN 8
const uint8_t buttonPins[] = {11,10,9,8,7,6,5,4};
const int buttonTones[] ={
NOTE_C4, NOTE_D4, NOTE_E4,
NOTE_F4, NOTE_G4, NOTE_A4, NOTE_B4,
};
 const int numTones = sizeof(buttonPins)/sizeof(buttonPins[0]);
 
void setup() {
for (uint8_t i=0; i<numTones; i++){
pinMode(buttonPins[i], INPUT_PULLUP);
}
 pinMode(SPEAKER_PIN, OUTPUT);
}

void loop() {
  int pitch = 0;
  for (uint8_t i=0; i<numTones; i++){
   if(digitalRead(buttonPins[i])==LOW) {
    pitch=buttonPins[i];
   }
 }

 if(pitch){
   tone(SPEAKER_PIN,pitch);
 }else{
  noTone(SPEAKER_PIN);
 }

}