const int trigPin = 9;
const int echoPin = 10;
const int buzzerPin = 8;

long duration;
int distance;

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

void loop() {
  // Kirim sinyal ultrasonik
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Hitung durasi pantulan
  duration = pulseIn(echoPin, HIGH);

  // Konversi durasi ke jarak (dalam cm)
  distance = duration * 0.034 / 2;

  Serial.print("Jarak: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Cek apakah jarak kurang dari atau sama dengan 50 cm
  digitalWrite(buzzerPin, HIGH);
delay(1000);
digitalWrite(buzzerPin, LOW);
delay(1000);

}