int trig = 5;
int echo = 6;
int merah = 2;
int kuning = 3;
int hijau = 4;
int buzzer = 7;

void setup() {
  // put your setup code here, to run once:
pinMode(trig, OUTPUT);
pinMode(echo, INPUT);
pinMode(merah, OUTPUT);
pinMode(kuning, OUTPUT);
pinMode(hijau, OUTPUT);
pinMode(buzzer, OUTPUT);
Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(trig, HIGH);
delayMicroseconds(10);
digitalWrite(trig, LOW);
int durasi;
durasi = pulseIn(echo, HIGH);
int jarak;
jarak = durasi/2*0.034;

if(jarak>=300 && jarak<350)
{
  digitalWrite(merah, LOW);
  digitalWrite(kuning, LOW);
  digitalWrite(hijau, HIGH);
  Serial.println("hijau menyala");
}
else if(jarak<300 && jarak>=200)
{
  digitalWrite(merah, LOW);
  digitalWrite(kuning, HIGH);
  digitalWrite(hijau, LOW);
  Serial.println("kuning menyala");
}
else if(jarak<200 && jarak>=0)
{
  digitalWrite(merah, HIGH);
  digitalWrite(kuning, LOW);
  digitalWrite(hijau, LOW);
  digitalWrite(buzzer, HIGH);
  Serial.println("merah menyala");
}

}