#include <Servo.h>

Servo myServo;
const int trigPin = 9;
const int echoPin = 8;

void setup() {
  myServo.attach(3);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  Serial.begin(9600);
}

void loop() {
  // Ultrasonic measurement
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  long duration = pulseIn(echoPin, HIGH);
  int distance = duration * 0.034 / 2;
  
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
  
  // Map distance to servo angle
  int angle = map(distance, 0, 50, 0, 180);
  angle = constrain(angle, 0, 180);
  myServo.write(angle);
  
  delay(1000);
}