const int buttonPin = 2;
int buttonState = 0;
const int pinMerah = 9;
const int pinKuning = 10;
const int pinHijau = 11;

void setup() {
  // put your setup code here, to run once:
  pinMode(buttonPin, INPUT);
  pinMode(pinMerah, OUTPUT);
  pinMode(pinKuning, OUTPUT);
  pinMode(pinHijau, OUTPUT);
  digitalWrite(pinMerah, LOW);
  digitalWrite(pinKuning, LOW);
  digitalWrite(pinHijau, LOW);
}

void loop() {
  // put your main code here, to run repeatedly:
  buttonState = digitalRead(buttonPin);
  if (buttonState == HIGH) {
    digitalWrite(pinMerah, HIGH);
    digitalWrite(pinKuning, LOW);
    digitalWrite(pinHijau, LOW);
    delay(1000);
    digitalWrite(pinMerah, LOW);
    digitalWrite(pinKuning, HIGH);
    digitalWrite(pinHijau, LOW);
    delay(1000);
    digitalWrite(pinMerah, LOW);
    digitalWrite(pinKuning, LOW);
    digitalWrite(pinHijau, HIGH);
    delay(1000);
    digitalWrite(pinMerah, HIGH);
    digitalWrite(pinKuning, HIGH);
    digitalWrite(pinHijau, HIGH);
    delay(1000);
  } else {
    digitalWrite(pinMerah, LOW);
    digitalWrite(pinKuning, LOW);
    digitalWrite(pinHijau, LOW);
  }
}