#define pinECHO 4
#define pinTRIG 3
#define pinledMerah 9
#define pinledHijau 8
#define pinledKuning 10 
void setup(){
Serial.begin (115200) ;
pinMode(pinTRIG, OUTPUT);
pinMode(pinECHO, INPUT);
pinMode(pinledMerah, OUTPUT);
pinMode(pinledKuning, OUTPUT);
pinMode(pinledHijau, OUTPUT);
}
int BacaSensorJarak(){
digitalWrite(pinTRIG, LOW);
delayMicroseconds(3);
digitalWrite(pinTRIG, HIGH);
delayMicroseconds(7);
digitalWrite(pinTRIG, LOW);
int duration=pulseIn(pinECHO, HIGH)
return duration * 0.034/2;

void loop(){
if (BacaSensorJarak()>300){
  digitalWrite(pinledMerah, LOW);
  digitalWrite(pinledKuning, LOW);
  digitalWrite(pinledHijau, HIGH);
  Serial.println("Jarak Halangan:"+String(BacaSensorJarak()));
  Serial.println("AirDangkal");
}
else if  (BacaSensorJarak()>=200<=100){
digitalWrite(pinledMerah, LOW);
digitalWrite(pinledKuning, HIGH);
digitalWrite(pinledHijau, LOW);
Serial.println("Jarak Halangan:"+String(BacaSensorJarak()));
Serial.println("AirSedang");
}
else if  (BacaSensorJarak()<100){
digitalWrite(pinledMerah, HIGH);
digitalWrite (pinledKuning, LOW);
digitalWrite (pinledHijau, LOW);
Serial.println("Jarak Halangan:"+String(BacaSensorJarak()));
Serial. println("AirDalam");
}