Super Sanic

#define BUZZ 13
#define TRIG 10
#define ECHO 11

void setup() {
  pinMode(BUZZ, OUTPUT);
  pinMode(TRIG, OUTPUT);
  pinMode(ECHO, INPUT);
  Serial.begin(9600);
}

void loop() {
  clearSensor();
  Serial.print("Distance: ");
  int distance = pulse();
  Serial.println(distance);
  if (distance <= 12) {
    tone(BUZZ, distance*100);
  } else {
    noTone(BUZZ);
  }
  delay(50);
}

void clearSensor() {
  digitalWrite(TRIG, 0);
  delayMicroseconds(2);
}

double pulse() {
  digitalWrite(TRIG, 1);
  delayMicroseconds(10);
  digitalWrite(TRIG, 0);

  int d = pulseIn(ECHO, 1);

  return d*0.017;
}