// Define the pins for the ultrasonic sensor
const int trigPin = 9;
const int echoPin = 8;

void setup() {
  // Initialize serial communication
  Serial.begin(9600);

  // Set the trigger pin as output and echo pin as input
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  // Calculate the distance
  float distance = measureDistance();

  // Print the distance
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  delay(500); // Wait for half a second
}

float measureDistance() {
  // Send a short pulse to the trigger pin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Measure the pulse duration on the echo pin
  long duration = pulseIn(echoPin, HIGH);

  // Calculate the distance in centimeters
  float distance = duration * 0.034 / 2;

  return distance;
}