#include <Servo.h>

// Define the pins for the ultrasound sensor
const int trigPin = 8; // Trigger pin
const int echoPin = 9; // Echo pin

// Define the pin for the servo motor
const int servoPin = 7; // Servo motor pin

// Create a Servo object
Servo myServo;

void setup() {
  // Initialize serial communication
  Serial.begin(9600);
  
  // Define the pins as input or output
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  
  // Attach the servo to its pin
  myServo.attach(servoPin);
}

void loop() {
  // Clear the trigger pin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);

  // Send a 10 microsecond pulse to trigger the sensor
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Measure the duration of the pulse returned by the sensor
  long duration = pulseIn(echoPin, HIGH);

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

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

  // Check if distance is less than 25 cm
  if (distance < 25) {
    // If distance is less than 25 cm, rotate the servo motor
    myServo.write(90); // Rotate servo to 90 degrees
    delay(500); // Wait for the servo to reach its position
  } else {
    // If distance is greater than or equal to 25 cm, stop the servo motor
    myServo.write(0); // Rotate servo to 0 degrees
  }

  // Wait a short delay before taking the next reading
  delay(1000);
}