const int trigPin = 2;
const int echoPin = 4;
const int ledMerahPin = 5; // Pin LED merah
const int ledKuningPin = 6; // Pin LED kuning
const int ledHijauPin = 7; // Pin LED hijau


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

void loop() {
 digitalWrite(trigPin, LOW);
 delayMicroseconds(2);

digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);

long duration = pulseIn(echoPin, HIGH);
int distance_cm = duration / 58;

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

if (distance_cm < 10) {
    digitalWrite(ledMerahPin, HIGH);
    digitalWrite(ledKuningPin, LOW);
    digitalWrite(ledHijauPin, LOW);
  } else if (distance_cm < 50) {
    digitalWrite(ledMerahPin, LOW);
    digitalWrite(ledKuningPin, HIGH);
    digitalWrite(ledHijauPin, LOW);
  } else {
    digitalWrite(ledMerahPin, LOW);
    digitalWrite(ledKuningPin, LOW);
    digitalWrite(ledHijauPin, HIGH);
  }
  
  delay(500); // Delay sejenak sebelum mengulang
}