int a=15;
void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");
  pinMode(12, OUTPUT);
}

void loop() {
  digitalRead(a);
for(int i=0;i<a;i++) {
  if(i<4){
    tone(12,1000);
    }
    else if(i>4 && i<9){
      tone(12,5000);
    }
    else {
      noTone(12);
    }
    Serial.println(i);
  // put your main code here, to run repeatedly:
  delay(1000); // this speeds up the simulation
  }
}