#define TRIGGER_PIN 2
#define ECHO_PIN 3
#define LED_HIJAU 4
#define LED_KUNING 5
#define LED_MERAH 6
#define BATAS_TINGGI_AIR_MERAH 50
#define BATAS_TINGGI_AIR_KUNING 100

void setup() {
  Serial.begin(9600);
  pinMode(TRIGGER_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(LED_HIJAU, OUTPUT);
  pinMode(LED_KUNING, OUTPUT);
  pinMode(LED_MERAH, OUTPUT);
}

void loop() {
  long duration, distance;
  digitalWrite(TRIGGER_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIGGER_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGGER_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2;

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

  
  if (distance < BATAS_TINGGI_AIR_MERAH) {
   
    digitalWrite(LED_HIJAU, LOW);
    digitalWrite(LED_KUNING, LOW);
    digitalWrite(LED_MERAH, HIGH);
    Serial.println("KONDISI BAHAYA");

  } else if (distance < BATAS_TINGGI_AIR_KUNING) {
    digitalWrite(LED_HIJAU, LOW);
    digitalWrite(LED_KUNING, HIGH);
    digitalWrite(LED_MERAH, LOW);
    Serial.println("KONDISI SIAGA");
    
  } else { 
    digitalWrite(LED_HIJAU, HIGH);
    digitalWrite(LED_KUNING, LOW);
    digitalWrite(LED_MERAH, LOW);
    Serial.println("KONDISI AMAN");
  }

  delay(1000); 
}