void setup() {
  // put your setup code here, to run once:
  pinMode(0, OUTPUT); // lampu merah
  pinMode(1, OUTPUT); // lampu kuning
  pinMode(2, OUTPUT); // lampu ijo
  pinMode(3, OUTPUT); // buzzer
}

void loop() {
  // put your main code here, to run repeatedly:
  
  // lampu merah on/off
  digitalWrite(0, HIGH);
  digitalWrite(3, LOW); 
  delay(4500);
  digitalWrite(0, HIGH);
  digitalWrite(3, HIGH);
  delay(500);
  digitalWrite(0, LOW);
  digitalWrite(3, LOW);

  // Lampu Hijau on/off
  digitalWrite(2, HIGH);
  delay(7000);
  digitalWrite(2, LOW);

  // Lampu kuning on/off
  digitalWrite(1, HIGH);
  delay(500);
  digitalWrite(1, HIGH);
  digitalWrite(3, HIGH);
  delay(500);
  digitalWrite(1, LOW);
  digitalWrite(3, LOW);

  
}