// Define the pins for ultrasonic sensor
const int trigPin = 2;
const int echoPin = 3;

// Variables for calculating distance
long duration;
int distance;

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

  // Set trigPin as OUTPUT and echoPin as INPUT
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  // Send a short ultrasonic pulse
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Measure the duration of the pulse
  duration = pulseIn(echoPin, HIGH);

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

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

  // Check if the distance is less than 100cm
  if (distance < 100) {
    // Perform the desired action
    // Replace the following line with your desired action
    Serial.println("Object is too close!");
  }

  delay(500); // Delay before the next measurement
}