for(i=2; i<=9; i=i+1) {
 pinMode(i, INPUT);
 digitalWrite(i, HIGH);
}
for(;;) {
 t=0;
 if(digitalRead(2)==LOW) {
  t=523;
 }
 if(digitalRead(3) == LOW) {
  t=587;
 }
 if(digitalRead(4) == LOW) {
  t=659;
 }
 if(digitalRead(5) == LOW) {
  t=698;
 }
 if(digitalRead(6) == LOW) {
  t=784;
 }
 if(digitalRead(7) == LOW) {
  t=880;
 }
 if(digitalRead(8) == LOW) {
  t=988;
 }
 if(digitalRead(9) == LOW) {
  t=1046;
 }
 if (t!=0) {
  tone(10, t);
 } else {
  noTone(10);
 }
}