const int trigPin = 11;
const int echoPin = 12;

void setup() {
  Serial.begin(9600); // Start communication with your laptop
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  // 1. Send out the ultrasonic sound wave
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // 2. Measure the time it takes for the bounce to return
  long duration = pulseIn(echoPin, HIGH);

  // 3. Convert time to Centimeters (Speed of sound / 2)
  int distance = duration * 0.034 / 2;

  // 4. Print it to your laptop screen
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  delay(200); // Wait a fraction of a second before reading again
}