void setup() {
pinMode(13, INPUT);
pinMode(12, INPUT);
pinMode(11, INPUT);
pinMode(10,INPUT);
pinMode(5, OUTPUT);

}

void loop() {
  if(digitalRead(13)){
    tone(5,261,100);
  }
  if(digitalRead(12)){
    tone(5,293,100);
  }
  if(digitalRead(11)){
    tone(5,329,100);
  }
  if(digitalRead(10)){
    tone(5,392,100);
  }
  noTone(5);
}